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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
8434dc93 | 23 | #include <linux/tracefs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
76c813e2 | 28 | #include <linux/vmalloc.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
f76180bc | 35 | #include <linux/mount.h> |
7e53bd42 | 36 | #include <linux/rwsem.h> |
5a0e3ad6 | 37 | #include <linux/slab.h> |
bc0c38d1 SR |
38 | #include <linux/ctype.h> |
39 | #include <linux/init.h> | |
2a2cc8f7 | 40 | #include <linux/poll.h> |
b892e5c8 | 41 | #include <linux/nmi.h> |
bc0c38d1 | 42 | #include <linux/fs.h> |
478409dd | 43 | #include <linux/trace.h> |
8bd75c77 | 44 | #include <linux/sched/rt.h> |
86387f7e | 45 | |
bc0c38d1 | 46 | #include "trace.h" |
f0868d1e | 47 | #include "trace_output.h" |
bc0c38d1 | 48 | |
73c5162a SR |
49 | /* |
50 | * On boot up, the ring buffer is set to the minimum size, so that | |
51 | * we do not waste memory on systems that are not using tracing. | |
52 | */ | |
55034cd6 | 53 | bool ring_buffer_expanded; |
73c5162a | 54 | |
8e1b82e0 FW |
55 | /* |
56 | * We need to change this state when a selftest is running. | |
ff32504f FW |
57 | * A selftest will lurk into the ring-buffer to count the |
58 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 59 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
60 | * at the same time, giving false positive or negative results. |
61 | */ | |
8e1b82e0 | 62 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 63 | |
b2821ae6 SR |
64 | /* |
65 | * If a tracer is running, we do not want to run SELFTEST. | |
66 | */ | |
020e5f85 | 67 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 68 | |
0daa2302 SRRH |
69 | /* Pipe tracepoints to printk */ |
70 | struct trace_iterator *tracepoint_print_iter; | |
71 | int tracepoint_printk; | |
42391745 | 72 | static DEFINE_STATIC_KEY_FALSE(tracepoint_printk_key); |
0daa2302 | 73 | |
adf9f195 FW |
74 | /* For tracers that don't implement custom flags */ |
75 | static struct tracer_opt dummy_tracer_opt[] = { | |
76 | { } | |
77 | }; | |
78 | ||
8c1a49ae SRRH |
79 | static int |
80 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
81 | { |
82 | return 0; | |
83 | } | |
0f048701 | 84 | |
7ffbd48d SR |
85 | /* |
86 | * To prevent the comm cache from being overwritten when no | |
87 | * tracing is active, only save the comm when a trace event | |
88 | * occurred. | |
89 | */ | |
d914ba37 | 90 | static DEFINE_PER_CPU(bool, trace_taskinfo_save); |
7ffbd48d | 91 | |
0f048701 SR |
92 | /* |
93 | * Kill all tracing for good (never come back). | |
94 | * It is initialized to 1 but will turn to zero if the initialization | |
95 | * of the tracer is successful. But that is the only place that sets | |
96 | * this back to zero. | |
97 | */ | |
4fd27358 | 98 | static int tracing_disabled = 1; |
0f048701 | 99 | |
955b61e5 | 100 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 101 | |
944ac425 SR |
102 | /* |
103 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
104 | * | |
105 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
106 | * is set, then ftrace_dump is called. This will output the contents | |
107 | * of the ftrace buffers to the console. This is very useful for | |
108 | * capturing traces that lead to crashes and outputing it to a | |
109 | * serial console. | |
110 | * | |
111 | * It is default off, but you can enable it with either specifying | |
112 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
113 | * /proc/sys/kernel/ftrace_dump_on_oops |
114 | * Set 1 if you want to dump buffers of all CPUs | |
115 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 116 | */ |
cecbca96 FW |
117 | |
118 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 119 | |
de7edd31 SRRH |
120 | /* When set, tracing will stop when a WARN*() is hit */ |
121 | int __disable_trace_on_warning; | |
122 | ||
681bec03 JL |
123 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
124 | /* Map of enums to their values, for "eval_map" file */ | |
23bf8cb8 | 125 | struct trace_eval_map_head { |
9828413d SRRH |
126 | struct module *mod; |
127 | unsigned long length; | |
128 | }; | |
129 | ||
23bf8cb8 | 130 | union trace_eval_map_item; |
9828413d | 131 | |
23bf8cb8 | 132 | struct trace_eval_map_tail { |
9828413d SRRH |
133 | /* |
134 | * "end" is first and points to NULL as it must be different | |
00f4b652 | 135 | * than "mod" or "eval_string" |
9828413d | 136 | */ |
23bf8cb8 | 137 | union trace_eval_map_item *next; |
9828413d SRRH |
138 | const char *end; /* points to NULL */ |
139 | }; | |
140 | ||
1793ed93 | 141 | static DEFINE_MUTEX(trace_eval_mutex); |
9828413d SRRH |
142 | |
143 | /* | |
23bf8cb8 | 144 | * The trace_eval_maps are saved in an array with two extra elements, |
9828413d SRRH |
145 | * one at the beginning, and one at the end. The beginning item contains |
146 | * the count of the saved maps (head.length), and the module they | |
147 | * belong to if not built in (head.mod). The ending item contains a | |
681bec03 | 148 | * pointer to the next array of saved eval_map items. |
9828413d | 149 | */ |
23bf8cb8 | 150 | union trace_eval_map_item { |
00f4b652 | 151 | struct trace_eval_map map; |
23bf8cb8 JL |
152 | struct trace_eval_map_head head; |
153 | struct trace_eval_map_tail tail; | |
9828413d SRRH |
154 | }; |
155 | ||
23bf8cb8 | 156 | static union trace_eval_map_item *trace_eval_maps; |
681bec03 | 157 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 158 | |
607e2ea1 | 159 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 160 | |
ee6c2c1b LZ |
161 | #define MAX_TRACER_SIZE 100 |
162 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 163 | static char *default_bootup_tracer; |
d9e54076 | 164 | |
55034cd6 SRRH |
165 | static bool allocate_snapshot; |
166 | ||
1beee96b | 167 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 168 | { |
67012ab1 | 169 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 170 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 171 | /* We are using ftrace early, expand it */ |
55034cd6 | 172 | ring_buffer_expanded = true; |
d9e54076 PZ |
173 | return 1; |
174 | } | |
1beee96b | 175 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 176 | |
944ac425 SR |
177 | static int __init set_ftrace_dump_on_oops(char *str) |
178 | { | |
cecbca96 FW |
179 | if (*str++ != '=' || !*str) { |
180 | ftrace_dump_on_oops = DUMP_ALL; | |
181 | return 1; | |
182 | } | |
183 | ||
184 | if (!strcmp("orig_cpu", str)) { | |
185 | ftrace_dump_on_oops = DUMP_ORIG; | |
186 | return 1; | |
187 | } | |
188 | ||
189 | return 0; | |
944ac425 SR |
190 | } |
191 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 192 | |
de7edd31 SRRH |
193 | static int __init stop_trace_on_warning(char *str) |
194 | { | |
933ff9f2 LCG |
195 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
196 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
197 | return 1; |
198 | } | |
933ff9f2 | 199 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 200 | |
3209cff4 | 201 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
202 | { |
203 | allocate_snapshot = true; | |
204 | /* We also need the main ring buffer expanded */ | |
205 | ring_buffer_expanded = true; | |
206 | return 1; | |
207 | } | |
3209cff4 | 208 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 209 | |
7bcfaf54 SR |
210 | |
211 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
7bcfaf54 SR |
212 | |
213 | static int __init set_trace_boot_options(char *str) | |
214 | { | |
67012ab1 | 215 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
216 | return 0; |
217 | } | |
218 | __setup("trace_options=", set_trace_boot_options); | |
219 | ||
e1e232ca SR |
220 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
221 | static char *trace_boot_clock __initdata; | |
222 | ||
223 | static int __init set_trace_boot_clock(char *str) | |
224 | { | |
225 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
226 | trace_boot_clock = trace_boot_clock_buf; | |
227 | return 0; | |
228 | } | |
229 | __setup("trace_clock=", set_trace_boot_clock); | |
230 | ||
0daa2302 SRRH |
231 | static int __init set_tracepoint_printk(char *str) |
232 | { | |
233 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
234 | tracepoint_printk = 1; | |
235 | return 1; | |
236 | } | |
237 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 238 | |
a5a1d1c2 | 239 | unsigned long long ns2usecs(u64 nsec) |
bc0c38d1 SR |
240 | { |
241 | nsec += 500; | |
242 | do_div(nsec, 1000); | |
243 | return nsec; | |
244 | } | |
245 | ||
983f938a SRRH |
246 | /* trace_flags holds trace_options default values */ |
247 | #define TRACE_DEFAULT_FLAGS \ | |
248 | (FUNCTION_DEFAULT_FLAGS | \ | |
249 | TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ | |
250 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ | |
251 | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ | |
252 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS) | |
253 | ||
16270145 SRRH |
254 | /* trace_options that are only supported by global_trace */ |
255 | #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ | |
256 | TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) | |
257 | ||
20550622 SRRH |
258 | /* trace_flags that are default zero for instances */ |
259 | #define ZEROED_TRACE_FLAGS \ | |
1e10486f | 260 | (TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK) |
16270145 | 261 | |
4fcdae83 | 262 | /* |
67d04bb2 JF |
263 | * The global_trace is the descriptor that holds the top-level tracing |
264 | * buffers for the live tracing. | |
4fcdae83 | 265 | */ |
983f938a SRRH |
266 | static struct trace_array global_trace = { |
267 | .trace_flags = TRACE_DEFAULT_FLAGS, | |
268 | }; | |
bc0c38d1 | 269 | |
ae63b31e | 270 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 271 | |
ff451961 SRRH |
272 | int trace_array_get(struct trace_array *this_tr) |
273 | { | |
274 | struct trace_array *tr; | |
275 | int ret = -ENODEV; | |
276 | ||
277 | mutex_lock(&trace_types_lock); | |
278 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
279 | if (tr == this_tr) { | |
280 | tr->ref++; | |
281 | ret = 0; | |
282 | break; | |
283 | } | |
284 | } | |
285 | mutex_unlock(&trace_types_lock); | |
286 | ||
287 | return ret; | |
288 | } | |
289 | ||
290 | static void __trace_array_put(struct trace_array *this_tr) | |
291 | { | |
292 | WARN_ON(!this_tr->ref); | |
293 | this_tr->ref--; | |
294 | } | |
295 | ||
296 | void trace_array_put(struct trace_array *this_tr) | |
297 | { | |
298 | mutex_lock(&trace_types_lock); | |
299 | __trace_array_put(this_tr); | |
300 | mutex_unlock(&trace_types_lock); | |
301 | } | |
302 | ||
2425bcb9 | 303 | int call_filter_check_discard(struct trace_event_call *call, void *rec, |
f306cc82 TZ |
304 | struct ring_buffer *buffer, |
305 | struct ring_buffer_event *event) | |
306 | { | |
307 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
308 | !filter_match_preds(call->filter, rec)) { | |
0fc1b09f | 309 | __trace_event_discard_commit(buffer, event); |
f306cc82 TZ |
310 | return 1; |
311 | } | |
312 | ||
313 | return 0; | |
eb02ce01 TZ |
314 | } |
315 | ||
76c813e2 SRRH |
316 | void trace_free_pid_list(struct trace_pid_list *pid_list) |
317 | { | |
318 | vfree(pid_list->pids); | |
319 | kfree(pid_list); | |
320 | } | |
321 | ||
d8275c45 SR |
322 | /** |
323 | * trace_find_filtered_pid - check if a pid exists in a filtered_pid list | |
324 | * @filtered_pids: The list of pids to check | |
325 | * @search_pid: The PID to find in @filtered_pids | |
326 | * | |
327 | * Returns true if @search_pid is fonud in @filtered_pids, and false otherwis. | |
328 | */ | |
329 | bool | |
330 | trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid) | |
331 | { | |
332 | /* | |
333 | * If pid_max changed after filtered_pids was created, we | |
334 | * by default ignore all pids greater than the previous pid_max. | |
335 | */ | |
336 | if (search_pid >= filtered_pids->pid_max) | |
337 | return false; | |
338 | ||
339 | return test_bit(search_pid, filtered_pids->pids); | |
340 | } | |
341 | ||
342 | /** | |
343 | * trace_ignore_this_task - should a task be ignored for tracing | |
344 | * @filtered_pids: The list of pids to check | |
345 | * @task: The task that should be ignored if not filtered | |
346 | * | |
347 | * Checks if @task should be traced or not from @filtered_pids. | |
348 | * Returns true if @task should *NOT* be traced. | |
349 | * Returns false if @task should be traced. | |
350 | */ | |
351 | bool | |
352 | trace_ignore_this_task(struct trace_pid_list *filtered_pids, struct task_struct *task) | |
353 | { | |
354 | /* | |
355 | * Return false, because if filtered_pids does not exist, | |
356 | * all pids are good to trace. | |
357 | */ | |
358 | if (!filtered_pids) | |
359 | return false; | |
360 | ||
361 | return !trace_find_filtered_pid(filtered_pids, task->pid); | |
362 | } | |
363 | ||
364 | /** | |
365 | * trace_pid_filter_add_remove - Add or remove a task from a pid_list | |
366 | * @pid_list: The list to modify | |
367 | * @self: The current task for fork or NULL for exit | |
368 | * @task: The task to add or remove | |
369 | * | |
370 | * If adding a task, if @self is defined, the task is only added if @self | |
371 | * is also included in @pid_list. This happens on fork and tasks should | |
372 | * only be added when the parent is listed. If @self is NULL, then the | |
373 | * @task pid will be removed from the list, which would happen on exit | |
374 | * of a task. | |
375 | */ | |
376 | void trace_filter_add_remove_task(struct trace_pid_list *pid_list, | |
377 | struct task_struct *self, | |
378 | struct task_struct *task) | |
379 | { | |
380 | if (!pid_list) | |
381 | return; | |
382 | ||
383 | /* For forks, we only add if the forking task is listed */ | |
384 | if (self) { | |
385 | if (!trace_find_filtered_pid(pid_list, self->pid)) | |
386 | return; | |
387 | } | |
388 | ||
389 | /* Sorry, but we don't support pid_max changing after setting */ | |
390 | if (task->pid >= pid_list->pid_max) | |
391 | return; | |
392 | ||
393 | /* "self" is set for forks, and NULL for exits */ | |
394 | if (self) | |
395 | set_bit(task->pid, pid_list->pids); | |
396 | else | |
397 | clear_bit(task->pid, pid_list->pids); | |
398 | } | |
399 | ||
5cc8976b SRRH |
400 | /** |
401 | * trace_pid_next - Used for seq_file to get to the next pid of a pid_list | |
402 | * @pid_list: The pid list to show | |
403 | * @v: The last pid that was shown (+1 the actual pid to let zero be displayed) | |
404 | * @pos: The position of the file | |
405 | * | |
406 | * This is used by the seq_file "next" operation to iterate the pids | |
407 | * listed in a trace_pid_list structure. | |
408 | * | |
409 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
410 | * stop the iteration. | |
411 | */ | |
412 | void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos) | |
413 | { | |
414 | unsigned long pid = (unsigned long)v; | |
415 | ||
416 | (*pos)++; | |
417 | ||
418 | /* pid already is +1 of the actual prevous bit */ | |
419 | pid = find_next_bit(pid_list->pids, pid_list->pid_max, pid); | |
420 | ||
421 | /* Return pid + 1 to allow zero to be represented */ | |
422 | if (pid < pid_list->pid_max) | |
423 | return (void *)(pid + 1); | |
424 | ||
425 | return NULL; | |
426 | } | |
427 | ||
428 | /** | |
429 | * trace_pid_start - Used for seq_file to start reading pid lists | |
430 | * @pid_list: The pid list to show | |
431 | * @pos: The position of the file | |
432 | * | |
433 | * This is used by seq_file "start" operation to start the iteration | |
434 | * of listing pids. | |
435 | * | |
436 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
437 | * stop the iteration. | |
438 | */ | |
439 | void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos) | |
440 | { | |
441 | unsigned long pid; | |
442 | loff_t l = 0; | |
443 | ||
444 | pid = find_first_bit(pid_list->pids, pid_list->pid_max); | |
445 | if (pid >= pid_list->pid_max) | |
446 | return NULL; | |
447 | ||
448 | /* Return pid + 1 so that zero can be the exit value */ | |
449 | for (pid++; pid && l < *pos; | |
450 | pid = (unsigned long)trace_pid_next(pid_list, (void *)pid, &l)) | |
451 | ; | |
452 | return (void *)pid; | |
453 | } | |
454 | ||
455 | /** | |
456 | * trace_pid_show - show the current pid in seq_file processing | |
457 | * @m: The seq_file structure to write into | |
458 | * @v: A void pointer of the pid (+1) value to display | |
459 | * | |
460 | * Can be directly used by seq_file operations to display the current | |
461 | * pid value. | |
462 | */ | |
463 | int trace_pid_show(struct seq_file *m, void *v) | |
464 | { | |
465 | unsigned long pid = (unsigned long)v - 1; | |
466 | ||
467 | seq_printf(m, "%lu\n", pid); | |
468 | return 0; | |
469 | } | |
470 | ||
76c813e2 SRRH |
471 | /* 128 should be much more than enough */ |
472 | #define PID_BUF_SIZE 127 | |
473 | ||
474 | int trace_pid_write(struct trace_pid_list *filtered_pids, | |
475 | struct trace_pid_list **new_pid_list, | |
476 | const char __user *ubuf, size_t cnt) | |
477 | { | |
478 | struct trace_pid_list *pid_list; | |
479 | struct trace_parser parser; | |
480 | unsigned long val; | |
481 | int nr_pids = 0; | |
482 | ssize_t read = 0; | |
483 | ssize_t ret = 0; | |
484 | loff_t pos; | |
485 | pid_t pid; | |
486 | ||
487 | if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1)) | |
488 | return -ENOMEM; | |
489 | ||
490 | /* | |
491 | * Always recreate a new array. The write is an all or nothing | |
492 | * operation. Always create a new array when adding new pids by | |
493 | * the user. If the operation fails, then the current list is | |
494 | * not modified. | |
495 | */ | |
496 | pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); | |
5cc7ae88 WW |
497 | if (!pid_list) { |
498 | trace_parser_put(&parser); | |
76c813e2 | 499 | return -ENOMEM; |
5cc7ae88 | 500 | } |
76c813e2 SRRH |
501 | |
502 | pid_list->pid_max = READ_ONCE(pid_max); | |
503 | ||
504 | /* Only truncating will shrink pid_max */ | |
505 | if (filtered_pids && filtered_pids->pid_max > pid_list->pid_max) | |
506 | pid_list->pid_max = filtered_pids->pid_max; | |
507 | ||
508 | pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3); | |
509 | if (!pid_list->pids) { | |
5cc7ae88 | 510 | trace_parser_put(&parser); |
76c813e2 SRRH |
511 | kfree(pid_list); |
512 | return -ENOMEM; | |
513 | } | |
514 | ||
515 | if (filtered_pids) { | |
516 | /* copy the current bits to the new max */ | |
67f20b08 WY |
517 | for_each_set_bit(pid, filtered_pids->pids, |
518 | filtered_pids->pid_max) { | |
76c813e2 | 519 | set_bit(pid, pid_list->pids); |
76c813e2 SRRH |
520 | nr_pids++; |
521 | } | |
522 | } | |
523 | ||
524 | while (cnt > 0) { | |
525 | ||
526 | pos = 0; | |
527 | ||
528 | ret = trace_get_user(&parser, ubuf, cnt, &pos); | |
529 | if (ret < 0 || !trace_parser_loaded(&parser)) | |
530 | break; | |
531 | ||
532 | read += ret; | |
533 | ubuf += ret; | |
534 | cnt -= ret; | |
535 | ||
536 | parser.buffer[parser.idx] = 0; | |
537 | ||
538 | ret = -EINVAL; | |
539 | if (kstrtoul(parser.buffer, 0, &val)) | |
540 | break; | |
541 | if (val >= pid_list->pid_max) | |
542 | break; | |
543 | ||
544 | pid = (pid_t)val; | |
545 | ||
546 | set_bit(pid, pid_list->pids); | |
547 | nr_pids++; | |
548 | ||
549 | trace_parser_clear(&parser); | |
550 | ret = 0; | |
551 | } | |
552 | trace_parser_put(&parser); | |
553 | ||
554 | if (ret < 0) { | |
555 | trace_free_pid_list(pid_list); | |
556 | return ret; | |
557 | } | |
558 | ||
559 | if (!nr_pids) { | |
560 | /* Cleared the list of pids */ | |
561 | trace_free_pid_list(pid_list); | |
562 | read = ret; | |
563 | pid_list = NULL; | |
564 | } | |
565 | ||
566 | *new_pid_list = pid_list; | |
567 | ||
568 | return read; | |
569 | } | |
570 | ||
a5a1d1c2 | 571 | static u64 buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
572 | { |
573 | u64 ts; | |
574 | ||
575 | /* Early boot up does not have a buffer yet */ | |
9457158b | 576 | if (!buf->buffer) |
37886f6a SR |
577 | return trace_clock_local(); |
578 | ||
9457158b AL |
579 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
580 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
581 | |
582 | return ts; | |
583 | } | |
bc0c38d1 | 584 | |
a5a1d1c2 | 585 | u64 ftrace_now(int cpu) |
9457158b AL |
586 | { |
587 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
588 | } | |
589 | ||
10246fa3 SRRH |
590 | /** |
591 | * tracing_is_enabled - Show if global_trace has been disabled | |
592 | * | |
593 | * Shows if the global trace has been enabled or not. It uses the | |
594 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
595 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
596 | * need to know the accurate state, use tracing_is_on() which is a little | |
597 | * slower, but accurate. | |
598 | */ | |
9036990d SR |
599 | int tracing_is_enabled(void) |
600 | { | |
10246fa3 SRRH |
601 | /* |
602 | * For quick access (irqsoff uses this in fast path), just | |
603 | * return the mirror variable of the state of the ring buffer. | |
604 | * It's a little racy, but we don't really care. | |
605 | */ | |
606 | smp_rmb(); | |
607 | return !global_trace.buffer_disabled; | |
9036990d SR |
608 | } |
609 | ||
4fcdae83 | 610 | /* |
3928a8a2 SR |
611 | * trace_buf_size is the size in bytes that is allocated |
612 | * for a buffer. Note, the number of bytes is always rounded | |
613 | * to page size. | |
3f5a54e3 SR |
614 | * |
615 | * This number is purposely set to a low number of 16384. | |
616 | * If the dump on oops happens, it will be much appreciated | |
617 | * to not have to wait for all that output. Anyway this can be | |
618 | * boot time and run time configurable. | |
4fcdae83 | 619 | */ |
3928a8a2 | 620 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 621 | |
3928a8a2 | 622 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 623 | |
4fcdae83 | 624 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 625 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 626 | |
4fcdae83 SR |
627 | /* |
628 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 629 | */ |
a8227415 | 630 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 631 | |
7e53bd42 LJ |
632 | /* |
633 | * serialize the access of the ring buffer | |
634 | * | |
635 | * ring buffer serializes readers, but it is low level protection. | |
636 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
637 | * are not protected by ring buffer. | |
638 | * | |
639 | * The content of events may become garbage if we allow other process consumes | |
640 | * these events concurrently: | |
641 | * A) the page of the consumed events may become a normal page | |
642 | * (not reader page) in ring buffer, and this page will be rewrited | |
643 | * by events producer. | |
644 | * B) The page of the consumed events may become a page for splice_read, | |
645 | * and this page will be returned to system. | |
646 | * | |
647 | * These primitives allow multi process access to different cpu ring buffer | |
648 | * concurrently. | |
649 | * | |
650 | * These primitives don't distinguish read-only and read-consume access. | |
651 | * Multi read-only access are also serialized. | |
652 | */ | |
653 | ||
654 | #ifdef CONFIG_SMP | |
655 | static DECLARE_RWSEM(all_cpu_access_lock); | |
656 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
657 | ||
658 | static inline void trace_access_lock(int cpu) | |
659 | { | |
ae3b5093 | 660 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
661 | /* gain it for accessing the whole ring buffer. */ |
662 | down_write(&all_cpu_access_lock); | |
663 | } else { | |
664 | /* gain it for accessing a cpu ring buffer. */ | |
665 | ||
ae3b5093 | 666 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
667 | down_read(&all_cpu_access_lock); |
668 | ||
669 | /* Secondly block other access to this @cpu ring buffer. */ | |
670 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
671 | } | |
672 | } | |
673 | ||
674 | static inline void trace_access_unlock(int cpu) | |
675 | { | |
ae3b5093 | 676 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
677 | up_write(&all_cpu_access_lock); |
678 | } else { | |
679 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
680 | up_read(&all_cpu_access_lock); | |
681 | } | |
682 | } | |
683 | ||
684 | static inline void trace_access_lock_init(void) | |
685 | { | |
686 | int cpu; | |
687 | ||
688 | for_each_possible_cpu(cpu) | |
689 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
690 | } | |
691 | ||
692 | #else | |
693 | ||
694 | static DEFINE_MUTEX(access_lock); | |
695 | ||
696 | static inline void trace_access_lock(int cpu) | |
697 | { | |
698 | (void)cpu; | |
699 | mutex_lock(&access_lock); | |
700 | } | |
701 | ||
702 | static inline void trace_access_unlock(int cpu) | |
703 | { | |
704 | (void)cpu; | |
705 | mutex_unlock(&access_lock); | |
706 | } | |
707 | ||
708 | static inline void trace_access_lock_init(void) | |
709 | { | |
710 | } | |
711 | ||
712 | #endif | |
713 | ||
d78a4614 SRRH |
714 | #ifdef CONFIG_STACKTRACE |
715 | static void __ftrace_trace_stack(struct ring_buffer *buffer, | |
716 | unsigned long flags, | |
717 | int skip, int pc, struct pt_regs *regs); | |
2d34f489 SRRH |
718 | static inline void ftrace_trace_stack(struct trace_array *tr, |
719 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
720 | unsigned long flags, |
721 | int skip, int pc, struct pt_regs *regs); | |
ca475e83 | 722 | |
d78a4614 SRRH |
723 | #else |
724 | static inline void __ftrace_trace_stack(struct ring_buffer *buffer, | |
725 | unsigned long flags, | |
726 | int skip, int pc, struct pt_regs *regs) | |
727 | { | |
728 | } | |
2d34f489 SRRH |
729 | static inline void ftrace_trace_stack(struct trace_array *tr, |
730 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
731 | unsigned long flags, |
732 | int skip, int pc, struct pt_regs *regs) | |
ca475e83 SRRH |
733 | { |
734 | } | |
735 | ||
d78a4614 SRRH |
736 | #endif |
737 | ||
3e9a8aad SRRH |
738 | static __always_inline void |
739 | trace_event_setup(struct ring_buffer_event *event, | |
740 | int type, unsigned long flags, int pc) | |
741 | { | |
742 | struct trace_entry *ent = ring_buffer_event_data(event); | |
743 | ||
744 | tracing_generic_entry_update(ent, flags, pc); | |
745 | ent->type = type; | |
746 | } | |
747 | ||
748 | static __always_inline struct ring_buffer_event * | |
749 | __trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
750 | int type, | |
751 | unsigned long len, | |
752 | unsigned long flags, int pc) | |
753 | { | |
754 | struct ring_buffer_event *event; | |
755 | ||
756 | event = ring_buffer_lock_reserve(buffer, len); | |
757 | if (event != NULL) | |
758 | trace_event_setup(event, type, flags, pc); | |
759 | ||
760 | return event; | |
761 | } | |
762 | ||
2290f2c5 | 763 | void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
764 | { |
765 | if (tr->trace_buffer.buffer) | |
766 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
767 | /* | |
768 | * This flag is looked at when buffers haven't been allocated | |
769 | * yet, or by some tracers (like irqsoff), that just want to | |
770 | * know if the ring buffer has been disabled, but it can handle | |
771 | * races of where it gets disabled but we still do a record. | |
772 | * As the check is in the fast path of the tracers, it is more | |
773 | * important to be fast than accurate. | |
774 | */ | |
775 | tr->buffer_disabled = 0; | |
776 | /* Make the flag seen by readers */ | |
777 | smp_wmb(); | |
778 | } | |
779 | ||
499e5470 SR |
780 | /** |
781 | * tracing_on - enable tracing buffers | |
782 | * | |
783 | * This function enables tracing buffers that may have been | |
784 | * disabled with tracing_off. | |
785 | */ | |
786 | void tracing_on(void) | |
787 | { | |
10246fa3 | 788 | tracer_tracing_on(&global_trace); |
499e5470 SR |
789 | } |
790 | EXPORT_SYMBOL_GPL(tracing_on); | |
791 | ||
52ffabe3 SRRH |
792 | |
793 | static __always_inline void | |
794 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
795 | { | |
d914ba37 | 796 | __this_cpu_write(trace_taskinfo_save, true); |
52ffabe3 SRRH |
797 | |
798 | /* If this is the temp buffer, we need to commit fully */ | |
799 | if (this_cpu_read(trace_buffered_event) == event) { | |
800 | /* Length is in event->array[0] */ | |
801 | ring_buffer_write(buffer, event->array[0], &event->array[1]); | |
802 | /* Release the temp buffer */ | |
803 | this_cpu_dec(trace_buffered_event_cnt); | |
804 | } else | |
805 | ring_buffer_unlock_commit(buffer, event); | |
806 | } | |
807 | ||
09ae7234 SRRH |
808 | /** |
809 | * __trace_puts - write a constant string into the trace buffer. | |
810 | * @ip: The address of the caller | |
811 | * @str: The constant string to write | |
812 | * @size: The size of the string. | |
813 | */ | |
814 | int __trace_puts(unsigned long ip, const char *str, int size) | |
815 | { | |
816 | struct ring_buffer_event *event; | |
817 | struct ring_buffer *buffer; | |
818 | struct print_entry *entry; | |
819 | unsigned long irq_flags; | |
820 | int alloc; | |
8abfb872 J |
821 | int pc; |
822 | ||
983f938a | 823 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
824 | return 0; |
825 | ||
8abfb872 | 826 | pc = preempt_count(); |
09ae7234 | 827 | |
3132e107 SRRH |
828 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
829 | return 0; | |
830 | ||
09ae7234 SRRH |
831 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
832 | ||
833 | local_save_flags(irq_flags); | |
834 | buffer = global_trace.trace_buffer.buffer; | |
3e9a8aad SRRH |
835 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, |
836 | irq_flags, pc); | |
09ae7234 SRRH |
837 | if (!event) |
838 | return 0; | |
839 | ||
840 | entry = ring_buffer_event_data(event); | |
841 | entry->ip = ip; | |
842 | ||
843 | memcpy(&entry->buf, str, size); | |
844 | ||
845 | /* Add a newline if necessary */ | |
846 | if (entry->buf[size - 1] != '\n') { | |
847 | entry->buf[size] = '\n'; | |
848 | entry->buf[size + 1] = '\0'; | |
849 | } else | |
850 | entry->buf[size] = '\0'; | |
851 | ||
852 | __buffer_unlock_commit(buffer, event); | |
2d34f489 | 853 | ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); |
09ae7234 SRRH |
854 | |
855 | return size; | |
856 | } | |
857 | EXPORT_SYMBOL_GPL(__trace_puts); | |
858 | ||
859 | /** | |
860 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
861 | * @ip: The address of the caller | |
862 | * @str: The constant string to write to the buffer to | |
863 | */ | |
864 | int __trace_bputs(unsigned long ip, const char *str) | |
865 | { | |
866 | struct ring_buffer_event *event; | |
867 | struct ring_buffer *buffer; | |
868 | struct bputs_entry *entry; | |
869 | unsigned long irq_flags; | |
870 | int size = sizeof(struct bputs_entry); | |
8abfb872 J |
871 | int pc; |
872 | ||
983f938a | 873 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
874 | return 0; |
875 | ||
8abfb872 | 876 | pc = preempt_count(); |
09ae7234 | 877 | |
3132e107 SRRH |
878 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
879 | return 0; | |
880 | ||
09ae7234 SRRH |
881 | local_save_flags(irq_flags); |
882 | buffer = global_trace.trace_buffer.buffer; | |
3e9a8aad SRRH |
883 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, |
884 | irq_flags, pc); | |
09ae7234 SRRH |
885 | if (!event) |
886 | return 0; | |
887 | ||
888 | entry = ring_buffer_event_data(event); | |
889 | entry->ip = ip; | |
890 | entry->str = str; | |
891 | ||
892 | __buffer_unlock_commit(buffer, event); | |
2d34f489 | 893 | ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); |
09ae7234 SRRH |
894 | |
895 | return 1; | |
896 | } | |
897 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
898 | ||
ad909e21 | 899 | #ifdef CONFIG_TRACER_SNAPSHOT |
c6a95f37 | 900 | void tracing_snapshot_instance(struct trace_array *tr) |
ad909e21 | 901 | { |
ad909e21 SRRH |
902 | struct tracer *tracer = tr->current_trace; |
903 | unsigned long flags; | |
904 | ||
1b22e382 SRRH |
905 | if (in_nmi()) { |
906 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
907 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
908 | return; | |
909 | } | |
910 | ||
ad909e21 | 911 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
912 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
913 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
914 | tracing_off(); |
915 | return; | |
916 | } | |
917 | ||
918 | /* Note, snapshot can not be used when the tracer uses it */ | |
919 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
920 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
921 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
922 | return; |
923 | } | |
924 | ||
925 | local_irq_save(flags); | |
926 | update_max_tr(tr, current, smp_processor_id()); | |
927 | local_irq_restore(flags); | |
928 | } | |
cab50379 SRV |
929 | |
930 | /** | |
931 | * trace_snapshot - take a snapshot of the current buffer. | |
932 | * | |
933 | * This causes a swap between the snapshot buffer and the current live | |
934 | * tracing buffer. You can use this to take snapshots of the live | |
935 | * trace when some condition is triggered, but continue to trace. | |
936 | * | |
937 | * Note, make sure to allocate the snapshot with either | |
938 | * a tracing_snapshot_alloc(), or by doing it manually | |
939 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
940 | * | |
941 | * If the snapshot buffer is not allocated, it will stop tracing. | |
942 | * Basically making a permanent snapshot. | |
943 | */ | |
944 | void tracing_snapshot(void) | |
945 | { | |
946 | struct trace_array *tr = &global_trace; | |
947 | ||
948 | tracing_snapshot_instance(tr); | |
949 | } | |
1b22e382 | 950 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
951 | |
952 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
953 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
954 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
955 | ||
c6a95f37 | 956 | int tracing_alloc_snapshot_instance(struct trace_array *tr) |
3209cff4 SRRH |
957 | { |
958 | int ret; | |
959 | ||
960 | if (!tr->allocated_snapshot) { | |
961 | ||
962 | /* allocate spare buffer */ | |
963 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
964 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
965 | if (ret < 0) | |
966 | return ret; | |
967 | ||
968 | tr->allocated_snapshot = true; | |
969 | } | |
970 | ||
971 | return 0; | |
972 | } | |
973 | ||
ad1438a0 | 974 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
975 | { |
976 | /* | |
977 | * We don't free the ring buffer. instead, resize it because | |
978 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
979 | * we want preserve it. | |
980 | */ | |
981 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
982 | set_buffer_entries(&tr->max_buffer, 1); | |
983 | tracing_reset_online_cpus(&tr->max_buffer); | |
984 | tr->allocated_snapshot = false; | |
985 | } | |
ad909e21 | 986 | |
93e31ffb TZ |
987 | /** |
988 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
989 | * | |
990 | * This only allocates the snapshot buffer if it isn't already | |
991 | * allocated - it doesn't also take a snapshot. | |
992 | * | |
993 | * This is meant to be used in cases where the snapshot buffer needs | |
994 | * to be set up for events that can't sleep but need to be able to | |
995 | * trigger a snapshot. | |
996 | */ | |
997 | int tracing_alloc_snapshot(void) | |
998 | { | |
999 | struct trace_array *tr = &global_trace; | |
1000 | int ret; | |
1001 | ||
c6a95f37 | 1002 | ret = tracing_alloc_snapshot_instance(tr); |
93e31ffb TZ |
1003 | WARN_ON(ret < 0); |
1004 | ||
1005 | return ret; | |
1006 | } | |
1007 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
1008 | ||
ad909e21 SRRH |
1009 | /** |
1010 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
1011 | * | |
1012 | * This is similar to trace_snapshot(), but it will allocate the | |
1013 | * snapshot buffer if it isn't already allocated. Use this only | |
1014 | * where it is safe to sleep, as the allocation may sleep. | |
1015 | * | |
1016 | * This causes a swap between the snapshot buffer and the current live | |
1017 | * tracing buffer. You can use this to take snapshots of the live | |
1018 | * trace when some condition is triggered, but continue to trace. | |
1019 | */ | |
1020 | void tracing_snapshot_alloc(void) | |
1021 | { | |
ad909e21 SRRH |
1022 | int ret; |
1023 | ||
93e31ffb TZ |
1024 | ret = tracing_alloc_snapshot(); |
1025 | if (ret < 0) | |
3209cff4 | 1026 | return; |
ad909e21 SRRH |
1027 | |
1028 | tracing_snapshot(); | |
1029 | } | |
1b22e382 | 1030 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
1031 | #else |
1032 | void tracing_snapshot(void) | |
1033 | { | |
1034 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
1035 | } | |
1b22e382 | 1036 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
1037 | int tracing_alloc_snapshot(void) |
1038 | { | |
1039 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
1040 | return -ENODEV; | |
1041 | } | |
1042 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
1043 | void tracing_snapshot_alloc(void) |
1044 | { | |
1045 | /* Give warning */ | |
1046 | tracing_snapshot(); | |
1047 | } | |
1b22e382 | 1048 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
1049 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
1050 | ||
2290f2c5 | 1051 | void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
1052 | { |
1053 | if (tr->trace_buffer.buffer) | |
1054 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
1055 | /* | |
1056 | * This flag is looked at when buffers haven't been allocated | |
1057 | * yet, or by some tracers (like irqsoff), that just want to | |
1058 | * know if the ring buffer has been disabled, but it can handle | |
1059 | * races of where it gets disabled but we still do a record. | |
1060 | * As the check is in the fast path of the tracers, it is more | |
1061 | * important to be fast than accurate. | |
1062 | */ | |
1063 | tr->buffer_disabled = 1; | |
1064 | /* Make the flag seen by readers */ | |
1065 | smp_wmb(); | |
1066 | } | |
1067 | ||
499e5470 SR |
1068 | /** |
1069 | * tracing_off - turn off tracing buffers | |
1070 | * | |
1071 | * This function stops the tracing buffers from recording data. | |
1072 | * It does not disable any overhead the tracers themselves may | |
1073 | * be causing. This function simply causes all recording to | |
1074 | * the ring buffers to fail. | |
1075 | */ | |
1076 | void tracing_off(void) | |
1077 | { | |
10246fa3 | 1078 | tracer_tracing_off(&global_trace); |
499e5470 SR |
1079 | } |
1080 | EXPORT_SYMBOL_GPL(tracing_off); | |
1081 | ||
de7edd31 SRRH |
1082 | void disable_trace_on_warning(void) |
1083 | { | |
1084 | if (__disable_trace_on_warning) | |
1085 | tracing_off(); | |
1086 | } | |
1087 | ||
10246fa3 SRRH |
1088 | /** |
1089 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
1090 | * @tr : the trace array to know if ring buffer is enabled | |
1091 | * | |
1092 | * Shows real state of the ring buffer if it is enabled or not. | |
1093 | */ | |
e7c15cd8 | 1094 | int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
1095 | { |
1096 | if (tr->trace_buffer.buffer) | |
1097 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
1098 | return !tr->buffer_disabled; | |
1099 | } | |
1100 | ||
499e5470 SR |
1101 | /** |
1102 | * tracing_is_on - show state of ring buffers enabled | |
1103 | */ | |
1104 | int tracing_is_on(void) | |
1105 | { | |
10246fa3 | 1106 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
1107 | } |
1108 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
1109 | ||
3928a8a2 | 1110 | static int __init set_buf_size(char *str) |
bc0c38d1 | 1111 | { |
3928a8a2 | 1112 | unsigned long buf_size; |
c6caeeb1 | 1113 | |
bc0c38d1 SR |
1114 | if (!str) |
1115 | return 0; | |
9d612bef | 1116 | buf_size = memparse(str, &str); |
c6caeeb1 | 1117 | /* nr_entries can not be zero */ |
9d612bef | 1118 | if (buf_size == 0) |
c6caeeb1 | 1119 | return 0; |
3928a8a2 | 1120 | trace_buf_size = buf_size; |
bc0c38d1 SR |
1121 | return 1; |
1122 | } | |
3928a8a2 | 1123 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 1124 | |
0e950173 TB |
1125 | static int __init set_tracing_thresh(char *str) |
1126 | { | |
87abb3b1 | 1127 | unsigned long threshold; |
0e950173 TB |
1128 | int ret; |
1129 | ||
1130 | if (!str) | |
1131 | return 0; | |
bcd83ea6 | 1132 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
1133 | if (ret < 0) |
1134 | return 0; | |
87abb3b1 | 1135 | tracing_thresh = threshold * 1000; |
0e950173 TB |
1136 | return 1; |
1137 | } | |
1138 | __setup("tracing_thresh=", set_tracing_thresh); | |
1139 | ||
57f50be1 SR |
1140 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
1141 | { | |
1142 | return nsecs / 1000; | |
1143 | } | |
1144 | ||
a3418a36 SRRH |
1145 | /* |
1146 | * TRACE_FLAGS is defined as a tuple matching bit masks with strings. | |
f57a4143 | 1147 | * It uses C(a, b) where 'a' is the eval (enum) name and 'b' is the string that |
a3418a36 | 1148 | * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list |
f57a4143 | 1149 | * of strings in the order that the evals (enum) were defined. |
a3418a36 SRRH |
1150 | */ |
1151 | #undef C | |
1152 | #define C(a, b) b | |
1153 | ||
4fcdae83 | 1154 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 | 1155 | static const char *trace_options[] = { |
a3418a36 | 1156 | TRACE_FLAGS |
bc0c38d1 SR |
1157 | NULL |
1158 | }; | |
1159 | ||
5079f326 Z |
1160 | static struct { |
1161 | u64 (*func)(void); | |
1162 | const char *name; | |
8be0709f | 1163 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 1164 | } trace_clocks[] = { |
1b3e5c09 TG |
1165 | { trace_clock_local, "local", 1 }, |
1166 | { trace_clock_global, "global", 1 }, | |
1167 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 1168 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
1169 | { trace_clock, "perf", 1 }, |
1170 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
aabfa5f2 | 1171 | { ktime_get_raw_fast_ns, "mono_raw", 1 }, |
80ec3552 | 1172 | { ktime_get_boot_fast_ns, "boot", 1 }, |
8cbd9cc6 | 1173 | ARCH_TRACE_CLOCKS |
5079f326 Z |
1174 | }; |
1175 | ||
b63f39ea | 1176 | /* |
1177 | * trace_parser_get_init - gets the buffer for trace parser | |
1178 | */ | |
1179 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
1180 | { | |
1181 | memset(parser, 0, sizeof(*parser)); | |
1182 | ||
1183 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
1184 | if (!parser->buffer) | |
1185 | return 1; | |
1186 | ||
1187 | parser->size = size; | |
1188 | return 0; | |
1189 | } | |
1190 | ||
1191 | /* | |
1192 | * trace_parser_put - frees the buffer for trace parser | |
1193 | */ | |
1194 | void trace_parser_put(struct trace_parser *parser) | |
1195 | { | |
1196 | kfree(parser->buffer); | |
0e684b65 | 1197 | parser->buffer = NULL; |
b63f39ea | 1198 | } |
1199 | ||
1200 | /* | |
1201 | * trace_get_user - reads the user input string separated by space | |
1202 | * (matched by isspace(ch)) | |
1203 | * | |
1204 | * For each string found the 'struct trace_parser' is updated, | |
1205 | * and the function returns. | |
1206 | * | |
1207 | * Returns number of bytes read. | |
1208 | * | |
1209 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
1210 | */ | |
1211 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
1212 | size_t cnt, loff_t *ppos) | |
1213 | { | |
1214 | char ch; | |
1215 | size_t read = 0; | |
1216 | ssize_t ret; | |
1217 | ||
1218 | if (!*ppos) | |
1219 | trace_parser_clear(parser); | |
1220 | ||
1221 | ret = get_user(ch, ubuf++); | |
1222 | if (ret) | |
1223 | goto out; | |
1224 | ||
1225 | read++; | |
1226 | cnt--; | |
1227 | ||
1228 | /* | |
1229 | * The parser is not finished with the last write, | |
1230 | * continue reading the user input without skipping spaces. | |
1231 | */ | |
1232 | if (!parser->cont) { | |
1233 | /* skip white space */ | |
1234 | while (cnt && isspace(ch)) { | |
1235 | ret = get_user(ch, ubuf++); | |
1236 | if (ret) | |
1237 | goto out; | |
1238 | read++; | |
1239 | cnt--; | |
1240 | } | |
1241 | ||
1242 | /* only spaces were written */ | |
1243 | if (isspace(ch)) { | |
1244 | *ppos += read; | |
1245 | ret = read; | |
1246 | goto out; | |
1247 | } | |
1248 | ||
1249 | parser->idx = 0; | |
1250 | } | |
1251 | ||
1252 | /* read the non-space input */ | |
1253 | while (cnt && !isspace(ch)) { | |
3c235a33 | 1254 | if (parser->idx < parser->size - 1) |
b63f39ea | 1255 | parser->buffer[parser->idx++] = ch; |
1256 | else { | |
1257 | ret = -EINVAL; | |
1258 | goto out; | |
1259 | } | |
1260 | ret = get_user(ch, ubuf++); | |
1261 | if (ret) | |
1262 | goto out; | |
1263 | read++; | |
1264 | cnt--; | |
1265 | } | |
1266 | ||
1267 | /* We either got finished input or we have to wait for another call. */ | |
1268 | if (isspace(ch)) { | |
1269 | parser->buffer[parser->idx] = 0; | |
1270 | parser->cont = false; | |
057db848 | 1271 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 1272 | parser->cont = true; |
1273 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
1274 | } else { |
1275 | ret = -EINVAL; | |
1276 | goto out; | |
b63f39ea | 1277 | } |
1278 | ||
1279 | *ppos += read; | |
1280 | ret = read; | |
1281 | ||
1282 | out: | |
1283 | return ret; | |
1284 | } | |
1285 | ||
3a161d99 | 1286 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 1287 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
1288 | { |
1289 | int len; | |
3c56819b | 1290 | |
5ac48378 | 1291 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
1292 | return -EBUSY; |
1293 | ||
5ac48378 | 1294 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1295 | if (cnt > len) |
1296 | cnt = len; | |
3a161d99 | 1297 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1298 | |
3a161d99 | 1299 | s->seq.readpos += cnt; |
3c56819b EGM |
1300 | return cnt; |
1301 | } | |
1302 | ||
0e950173 TB |
1303 | unsigned long __read_mostly tracing_thresh; |
1304 | ||
5d4a9dba | 1305 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
1306 | /* |
1307 | * Copy the new maximum trace into the separate maximum-trace | |
1308 | * structure. (this way the maximum trace is permanently saved, | |
1309 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
1310 | */ | |
1311 | static void | |
1312 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1313 | { | |
12883efb SRRH |
1314 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
1315 | struct trace_buffer *max_buf = &tr->max_buffer; | |
1316 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
1317 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1318 | |
12883efb SRRH |
1319 | max_buf->cpu = cpu; |
1320 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1321 | |
6d9b3fa5 | 1322 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1323 | max_data->critical_start = data->critical_start; |
1324 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1325 | |
1acaa1b2 | 1326 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1327 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1328 | /* |
1329 | * If tsk == current, then use current_uid(), as that does not use | |
1330 | * RCU. The irq tracer can be called out of RCU scope. | |
1331 | */ | |
1332 | if (tsk == current) | |
1333 | max_data->uid = current_uid(); | |
1334 | else | |
1335 | max_data->uid = task_uid(tsk); | |
1336 | ||
8248ac05 SR |
1337 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1338 | max_data->policy = tsk->policy; | |
1339 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1340 | |
1341 | /* record this tasks comm */ | |
1342 | tracing_record_cmdline(tsk); | |
1343 | } | |
1344 | ||
4fcdae83 SR |
1345 | /** |
1346 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1347 | * @tr: tracer | |
1348 | * @tsk: the task with the latency | |
1349 | * @cpu: The cpu that initiated the trace. | |
1350 | * | |
1351 | * Flip the buffers between the @tr and the max_tr and record information | |
1352 | * about which task was the cause of this latency. | |
1353 | */ | |
e309b41d | 1354 | void |
bc0c38d1 SR |
1355 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1356 | { | |
2721e72d | 1357 | struct ring_buffer *buf; |
bc0c38d1 | 1358 | |
2b6080f2 | 1359 | if (tr->stop_count) |
b8de7bd1 SR |
1360 | return; |
1361 | ||
4c11d7ae | 1362 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1363 | |
45ad21ca | 1364 | if (!tr->allocated_snapshot) { |
debdd57f | 1365 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1366 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1367 | return; |
debdd57f | 1368 | } |
34600f0e | 1369 | |
0b9b12c1 | 1370 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1371 | |
60baabc3 MH |
1372 | /* Inherit the recordable setting from trace_buffer */ |
1373 | if (ring_buffer_record_is_set_on(tr->trace_buffer.buffer)) | |
1374 | ring_buffer_record_on(tr->max_buffer.buffer); | |
1375 | else | |
1376 | ring_buffer_record_off(tr->max_buffer.buffer); | |
1377 | ||
12883efb SRRH |
1378 | buf = tr->trace_buffer.buffer; |
1379 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1380 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1381 | |
bc0c38d1 | 1382 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1383 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1384 | } |
1385 | ||
1386 | /** | |
1387 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1388 | * @tr - tracer | |
1389 | * @tsk - task with the latency | |
1390 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1391 | * |
1392 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1393 | */ |
e309b41d | 1394 | void |
bc0c38d1 SR |
1395 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1396 | { | |
3928a8a2 | 1397 | int ret; |
bc0c38d1 | 1398 | |
2b6080f2 | 1399 | if (tr->stop_count) |
b8de7bd1 SR |
1400 | return; |
1401 | ||
4c11d7ae | 1402 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1403 | if (!tr->allocated_snapshot) { |
2930e04d | 1404 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1405 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1406 | return; |
2930e04d | 1407 | } |
ef710e10 | 1408 | |
0b9b12c1 | 1409 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1410 | |
12883efb | 1411 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1412 | |
e8165dbb SR |
1413 | if (ret == -EBUSY) { |
1414 | /* | |
1415 | * We failed to swap the buffer due to a commit taking | |
1416 | * place on this CPU. We fail to record, but we reset | |
1417 | * the max trace buffer (no one writes directly to it) | |
1418 | * and flag that it failed. | |
1419 | */ | |
12883efb | 1420 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1421 | "Failed to swap buffers due to commit in progress\n"); |
1422 | } | |
1423 | ||
e8165dbb | 1424 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1425 | |
1426 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1427 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1428 | } |
5d4a9dba | 1429 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1430 | |
e30f53aa | 1431 | static int wait_on_pipe(struct trace_iterator *iter, bool full) |
0d5c6e1c | 1432 | { |
15693458 SRRH |
1433 | /* Iterators are static, they should be filled or empty */ |
1434 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1435 | return 0; |
0d5c6e1c | 1436 | |
e30f53aa RV |
1437 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, |
1438 | full); | |
0d5c6e1c SR |
1439 | } |
1440 | ||
f4e781c0 | 1441 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
9afecfbb SRV |
1442 | static bool selftests_can_run; |
1443 | ||
1444 | struct trace_selftests { | |
1445 | struct list_head list; | |
1446 | struct tracer *type; | |
1447 | }; | |
1448 | ||
1449 | static LIST_HEAD(postponed_selftests); | |
1450 | ||
1451 | static int save_selftest(struct tracer *type) | |
1452 | { | |
1453 | struct trace_selftests *selftest; | |
1454 | ||
1455 | selftest = kmalloc(sizeof(*selftest), GFP_KERNEL); | |
1456 | if (!selftest) | |
1457 | return -ENOMEM; | |
1458 | ||
1459 | selftest->type = type; | |
1460 | list_add(&selftest->list, &postponed_selftests); | |
1461 | return 0; | |
1462 | } | |
1463 | ||
f4e781c0 SRRH |
1464 | static int run_tracer_selftest(struct tracer *type) |
1465 | { | |
1466 | struct trace_array *tr = &global_trace; | |
1467 | struct tracer *saved_tracer = tr->current_trace; | |
1468 | int ret; | |
0d5c6e1c | 1469 | |
f4e781c0 SRRH |
1470 | if (!type->selftest || tracing_selftest_disabled) |
1471 | return 0; | |
0d5c6e1c | 1472 | |
9afecfbb SRV |
1473 | /* |
1474 | * If a tracer registers early in boot up (before scheduling is | |
1475 | * initialized and such), then do not run its selftests yet. | |
1476 | * Instead, run it a little later in the boot process. | |
1477 | */ | |
1478 | if (!selftests_can_run) | |
1479 | return save_selftest(type); | |
1480 | ||
0d5c6e1c | 1481 | /* |
f4e781c0 SRRH |
1482 | * Run a selftest on this tracer. |
1483 | * Here we reset the trace buffer, and set the current | |
1484 | * tracer to be this tracer. The tracer can then run some | |
1485 | * internal tracing to verify that everything is in order. | |
1486 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1487 | */ |
f4e781c0 | 1488 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1489 | |
f4e781c0 SRRH |
1490 | tr->current_trace = type; |
1491 | ||
1492 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1493 | if (type->use_max_tr) { | |
1494 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1495 | if (ring_buffer_expanded) | |
1496 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1497 | RING_BUFFER_ALL_CPUS); | |
1498 | tr->allocated_snapshot = true; | |
1499 | } | |
1500 | #endif | |
1501 | ||
1502 | /* the test is responsible for initializing and enabling */ | |
1503 | pr_info("Testing tracer %s: ", type->name); | |
1504 | ret = type->selftest(type, tr); | |
1505 | /* the test is responsible for resetting too */ | |
1506 | tr->current_trace = saved_tracer; | |
1507 | if (ret) { | |
1508 | printk(KERN_CONT "FAILED!\n"); | |
1509 | /* Add the warning after printing 'FAILED' */ | |
1510 | WARN_ON(1); | |
1511 | return -1; | |
1512 | } | |
1513 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1514 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1515 | ||
1516 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1517 | if (type->use_max_tr) { | |
1518 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1519 | |
f4e781c0 SRRH |
1520 | /* Shrink the max buffer again */ |
1521 | if (ring_buffer_expanded) | |
1522 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1523 | RING_BUFFER_ALL_CPUS); | |
1524 | } | |
1525 | #endif | |
1526 | ||
1527 | printk(KERN_CONT "PASSED\n"); | |
1528 | return 0; | |
1529 | } | |
9afecfbb SRV |
1530 | |
1531 | static __init int init_trace_selftests(void) | |
1532 | { | |
1533 | struct trace_selftests *p, *n; | |
1534 | struct tracer *t, **last; | |
1535 | int ret; | |
1536 | ||
1537 | selftests_can_run = true; | |
1538 | ||
1539 | mutex_lock(&trace_types_lock); | |
1540 | ||
1541 | if (list_empty(&postponed_selftests)) | |
1542 | goto out; | |
1543 | ||
1544 | pr_info("Running postponed tracer tests:\n"); | |
1545 | ||
581695e6 | 1546 | tracing_selftest_running = true; |
9afecfbb SRV |
1547 | list_for_each_entry_safe(p, n, &postponed_selftests, list) { |
1548 | ret = run_tracer_selftest(p->type); | |
1549 | /* If the test fails, then warn and remove from available_tracers */ | |
1550 | if (ret < 0) { | |
1551 | WARN(1, "tracer: %s failed selftest, disabling\n", | |
1552 | p->type->name); | |
1553 | last = &trace_types; | |
1554 | for (t = trace_types; t; t = t->next) { | |
1555 | if (t == p->type) { | |
1556 | *last = t->next; | |
1557 | break; | |
1558 | } | |
1559 | last = &t->next; | |
1560 | } | |
1561 | } | |
1562 | list_del(&p->list); | |
1563 | kfree(p); | |
1564 | } | |
581695e6 | 1565 | tracing_selftest_running = false; |
9afecfbb SRV |
1566 | |
1567 | out: | |
1568 | mutex_unlock(&trace_types_lock); | |
1569 | ||
1570 | return 0; | |
1571 | } | |
b9ef0326 | 1572 | core_initcall(init_trace_selftests); |
f4e781c0 SRRH |
1573 | #else |
1574 | static inline int run_tracer_selftest(struct tracer *type) | |
1575 | { | |
1576 | return 0; | |
0d5c6e1c | 1577 | } |
f4e781c0 | 1578 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1579 | |
41d9c0be SRRH |
1580 | static void add_tracer_options(struct trace_array *tr, struct tracer *t); |
1581 | ||
a4d1e688 JW |
1582 | static void __init apply_trace_boot_options(void); |
1583 | ||
4fcdae83 SR |
1584 | /** |
1585 | * register_tracer - register a tracer with the ftrace system. | |
1586 | * @type - the plugin for the tracer | |
1587 | * | |
1588 | * Register a new plugin tracer. | |
1589 | */ | |
a4d1e688 | 1590 | int __init register_tracer(struct tracer *type) |
bc0c38d1 SR |
1591 | { |
1592 | struct tracer *t; | |
bc0c38d1 SR |
1593 | int ret = 0; |
1594 | ||
1595 | if (!type->name) { | |
1596 | pr_info("Tracer must have a name\n"); | |
1597 | return -1; | |
1598 | } | |
1599 | ||
24a461d5 | 1600 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1601 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1602 | return -1; | |
1603 | } | |
1604 | ||
bc0c38d1 | 1605 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1606 | |
8e1b82e0 FW |
1607 | tracing_selftest_running = true; |
1608 | ||
bc0c38d1 SR |
1609 | for (t = trace_types; t; t = t->next) { |
1610 | if (strcmp(type->name, t->name) == 0) { | |
1611 | /* already found */ | |
ee6c2c1b | 1612 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1613 | type->name); |
1614 | ret = -1; | |
1615 | goto out; | |
1616 | } | |
1617 | } | |
1618 | ||
adf9f195 FW |
1619 | if (!type->set_flag) |
1620 | type->set_flag = &dummy_set_flag; | |
d39cdd20 CH |
1621 | if (!type->flags) { |
1622 | /*allocate a dummy tracer_flags*/ | |
1623 | type->flags = kmalloc(sizeof(*type->flags), GFP_KERNEL); | |
c8ca003b CH |
1624 | if (!type->flags) { |
1625 | ret = -ENOMEM; | |
1626 | goto out; | |
1627 | } | |
d39cdd20 CH |
1628 | type->flags->val = 0; |
1629 | type->flags->opts = dummy_tracer_opt; | |
1630 | } else | |
adf9f195 FW |
1631 | if (!type->flags->opts) |
1632 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1633 | |
d39cdd20 CH |
1634 | /* store the tracer for __set_tracer_option */ |
1635 | type->flags->trace = type; | |
1636 | ||
f4e781c0 SRRH |
1637 | ret = run_tracer_selftest(type); |
1638 | if (ret < 0) | |
1639 | goto out; | |
60a11774 | 1640 | |
bc0c38d1 SR |
1641 | type->next = trace_types; |
1642 | trace_types = type; | |
41d9c0be | 1643 | add_tracer_options(&global_trace, type); |
60a11774 | 1644 | |
bc0c38d1 | 1645 | out: |
8e1b82e0 | 1646 | tracing_selftest_running = false; |
bc0c38d1 SR |
1647 | mutex_unlock(&trace_types_lock); |
1648 | ||
dac74940 SR |
1649 | if (ret || !default_bootup_tracer) |
1650 | goto out_unlock; | |
1651 | ||
ee6c2c1b | 1652 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1653 | goto out_unlock; |
1654 | ||
1655 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1656 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1657 | tracing_set_tracer(&global_trace, type->name); |
dac74940 | 1658 | default_bootup_tracer = NULL; |
a4d1e688 JW |
1659 | |
1660 | apply_trace_boot_options(); | |
1661 | ||
dac74940 | 1662 | /* disable other selftests, since this will break it. */ |
55034cd6 | 1663 | tracing_selftest_disabled = true; |
b2821ae6 | 1664 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1665 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1666 | type->name); | |
b2821ae6 | 1667 | #endif |
b2821ae6 | 1668 | |
dac74940 | 1669 | out_unlock: |
bc0c38d1 SR |
1670 | return ret; |
1671 | } | |
1672 | ||
12883efb | 1673 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1674 | { |
12883efb | 1675 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1676 | |
a5416411 HT |
1677 | if (!buffer) |
1678 | return; | |
1679 | ||
f633903a SR |
1680 | ring_buffer_record_disable(buffer); |
1681 | ||
1682 | /* Make sure all commits have finished */ | |
1683 | synchronize_sched(); | |
68179686 | 1684 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1685 | |
1686 | ring_buffer_record_enable(buffer); | |
1687 | } | |
1688 | ||
12883efb | 1689 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1690 | { |
12883efb | 1691 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1692 | int cpu; |
1693 | ||
a5416411 HT |
1694 | if (!buffer) |
1695 | return; | |
1696 | ||
621968cd SR |
1697 | ring_buffer_record_disable(buffer); |
1698 | ||
1699 | /* Make sure all commits have finished */ | |
1700 | synchronize_sched(); | |
1701 | ||
9457158b | 1702 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1703 | |
1704 | for_each_online_cpu(cpu) | |
68179686 | 1705 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1706 | |
1707 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1708 | } |
1709 | ||
09d8091c | 1710 | /* Must have trace_types_lock held */ |
873c642f | 1711 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1712 | { |
873c642f SRRH |
1713 | struct trace_array *tr; |
1714 | ||
873c642f | 1715 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
065e63f9 SRV |
1716 | if (!tr->clear_trace) |
1717 | continue; | |
1718 | tr->clear_trace = false; | |
12883efb SRRH |
1719 | tracing_reset_online_cpus(&tr->trace_buffer); |
1720 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1721 | tracing_reset_online_cpus(&tr->max_buffer); | |
1722 | #endif | |
873c642f | 1723 | } |
9456f0fa SR |
1724 | } |
1725 | ||
d914ba37 JF |
1726 | static int *tgid_map; |
1727 | ||
939c7a4f | 1728 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1729 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1730 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1731 | struct saved_cmdlines_buffer { |
1732 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1733 | unsigned *map_cmdline_to_pid; | |
1734 | unsigned cmdline_num; | |
1735 | int cmdline_idx; | |
1736 | char *saved_cmdlines; | |
1737 | }; | |
1738 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1739 | |
25b0b44a | 1740 | /* temporary disable recording */ |
d914ba37 | 1741 | static atomic_t trace_record_taskinfo_disabled __read_mostly; |
bc0c38d1 | 1742 | |
939c7a4f YY |
1743 | static inline char *get_saved_cmdlines(int idx) |
1744 | { | |
1745 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1746 | } | |
1747 | ||
1748 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1749 | { |
939c7a4f YY |
1750 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1751 | } | |
1752 | ||
1753 | static int allocate_cmdlines_buffer(unsigned int val, | |
1754 | struct saved_cmdlines_buffer *s) | |
1755 | { | |
1756 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1757 | GFP_KERNEL); | |
1758 | if (!s->map_cmdline_to_pid) | |
1759 | return -ENOMEM; | |
1760 | ||
1761 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1762 | if (!s->saved_cmdlines) { | |
1763 | kfree(s->map_cmdline_to_pid); | |
1764 | return -ENOMEM; | |
1765 | } | |
1766 | ||
1767 | s->cmdline_idx = 0; | |
1768 | s->cmdline_num = val; | |
1769 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1770 | sizeof(s->map_pid_to_cmdline)); | |
1771 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1772 | val * sizeof(*s->map_cmdline_to_pid)); | |
1773 | ||
1774 | return 0; | |
1775 | } | |
1776 | ||
1777 | static int trace_create_savedcmd(void) | |
1778 | { | |
1779 | int ret; | |
1780 | ||
a6af8fbf | 1781 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1782 | if (!savedcmd) |
1783 | return -ENOMEM; | |
1784 | ||
1785 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1786 | if (ret < 0) { | |
1787 | kfree(savedcmd); | |
1788 | savedcmd = NULL; | |
1789 | return -ENOMEM; | |
1790 | } | |
1791 | ||
1792 | return 0; | |
bc0c38d1 SR |
1793 | } |
1794 | ||
b5130b1e CE |
1795 | int is_tracing_stopped(void) |
1796 | { | |
2b6080f2 | 1797 | return global_trace.stop_count; |
b5130b1e CE |
1798 | } |
1799 | ||
0f048701 SR |
1800 | /** |
1801 | * tracing_start - quick start of the tracer | |
1802 | * | |
1803 | * If tracing is enabled but was stopped by tracing_stop, | |
1804 | * this will start the tracer back up. | |
1805 | */ | |
1806 | void tracing_start(void) | |
1807 | { | |
1808 | struct ring_buffer *buffer; | |
1809 | unsigned long flags; | |
1810 | ||
1811 | if (tracing_disabled) | |
1812 | return; | |
1813 | ||
2b6080f2 SR |
1814 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1815 | if (--global_trace.stop_count) { | |
1816 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1817 | /* Someone screwed up their debugging */ |
1818 | WARN_ON_ONCE(1); | |
2b6080f2 | 1819 | global_trace.stop_count = 0; |
b06a8301 | 1820 | } |
0f048701 SR |
1821 | goto out; |
1822 | } | |
1823 | ||
a2f80714 | 1824 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1825 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1826 | |
12883efb | 1827 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1828 | if (buffer) |
1829 | ring_buffer_record_enable(buffer); | |
1830 | ||
12883efb SRRH |
1831 | #ifdef CONFIG_TRACER_MAX_TRACE |
1832 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1833 | if (buffer) |
1834 | ring_buffer_record_enable(buffer); | |
12883efb | 1835 | #endif |
0f048701 | 1836 | |
0b9b12c1 | 1837 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1838 | |
0f048701 | 1839 | out: |
2b6080f2 SR |
1840 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1841 | } | |
1842 | ||
1843 | static void tracing_start_tr(struct trace_array *tr) | |
1844 | { | |
1845 | struct ring_buffer *buffer; | |
1846 | unsigned long flags; | |
1847 | ||
1848 | if (tracing_disabled) | |
1849 | return; | |
1850 | ||
1851 | /* If global, we need to also start the max tracer */ | |
1852 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1853 | return tracing_start(); | |
1854 | ||
1855 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1856 | ||
1857 | if (--tr->stop_count) { | |
1858 | if (tr->stop_count < 0) { | |
1859 | /* Someone screwed up their debugging */ | |
1860 | WARN_ON_ONCE(1); | |
1861 | tr->stop_count = 0; | |
1862 | } | |
1863 | goto out; | |
1864 | } | |
1865 | ||
12883efb | 1866 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1867 | if (buffer) |
1868 | ring_buffer_record_enable(buffer); | |
1869 | ||
1870 | out: | |
1871 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1872 | } |
1873 | ||
1874 | /** | |
1875 | * tracing_stop - quick stop of the tracer | |
1876 | * | |
1877 | * Light weight way to stop tracing. Use in conjunction with | |
1878 | * tracing_start. | |
1879 | */ | |
1880 | void tracing_stop(void) | |
1881 | { | |
1882 | struct ring_buffer *buffer; | |
1883 | unsigned long flags; | |
1884 | ||
2b6080f2 SR |
1885 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1886 | if (global_trace.stop_count++) | |
0f048701 SR |
1887 | goto out; |
1888 | ||
a2f80714 | 1889 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1890 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1891 | |
12883efb | 1892 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1893 | if (buffer) |
1894 | ring_buffer_record_disable(buffer); | |
1895 | ||
12883efb SRRH |
1896 | #ifdef CONFIG_TRACER_MAX_TRACE |
1897 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1898 | if (buffer) |
1899 | ring_buffer_record_disable(buffer); | |
12883efb | 1900 | #endif |
0f048701 | 1901 | |
0b9b12c1 | 1902 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1903 | |
0f048701 | 1904 | out: |
2b6080f2 SR |
1905 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1906 | } | |
1907 | ||
1908 | static void tracing_stop_tr(struct trace_array *tr) | |
1909 | { | |
1910 | struct ring_buffer *buffer; | |
1911 | unsigned long flags; | |
1912 | ||
1913 | /* If global, we need to also stop the max tracer */ | |
1914 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1915 | return tracing_stop(); | |
1916 | ||
1917 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1918 | if (tr->stop_count++) | |
1919 | goto out; | |
1920 | ||
12883efb | 1921 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1922 | if (buffer) |
1923 | ring_buffer_record_disable(buffer); | |
1924 | ||
1925 | out: | |
1926 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1927 | } |
1928 | ||
379cfdac | 1929 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1930 | { |
a635cf04 | 1931 | unsigned pid, idx; |
bc0c38d1 | 1932 | |
eaf260ac JF |
1933 | /* treat recording of idle task as a success */ |
1934 | if (!tsk->pid) | |
1935 | return 1; | |
1936 | ||
1937 | if (unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1938 | return 0; |
bc0c38d1 SR |
1939 | |
1940 | /* | |
1941 | * It's not the end of the world if we don't get | |
1942 | * the lock, but we also don't want to spin | |
1943 | * nor do we want to disable interrupts, | |
1944 | * so if we miss here, then better luck next time. | |
1945 | */ | |
0199c4e6 | 1946 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1947 | return 0; |
bc0c38d1 | 1948 | |
939c7a4f | 1949 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1950 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1951 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1952 | |
a635cf04 CE |
1953 | /* |
1954 | * Check whether the cmdline buffer at idx has a pid | |
1955 | * mapped. We are going to overwrite that entry so we | |
1956 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1957 | * would read the new comm for the old pid. | |
1958 | */ | |
939c7a4f | 1959 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1960 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1961 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1962 | |
939c7a4f YY |
1963 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1964 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1965 | |
939c7a4f | 1966 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1967 | } |
1968 | ||
939c7a4f | 1969 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1970 | |
0199c4e6 | 1971 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1972 | |
1973 | return 1; | |
bc0c38d1 SR |
1974 | } |
1975 | ||
4c27e756 | 1976 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1977 | { |
bc0c38d1 SR |
1978 | unsigned map; |
1979 | ||
4ca53085 SR |
1980 | if (!pid) { |
1981 | strcpy(comm, "<idle>"); | |
1982 | return; | |
1983 | } | |
bc0c38d1 | 1984 | |
74bf4076 SR |
1985 | if (WARN_ON_ONCE(pid < 0)) { |
1986 | strcpy(comm, "<XXX>"); | |
1987 | return; | |
1988 | } | |
1989 | ||
4ca53085 SR |
1990 | if (pid > PID_MAX_DEFAULT) { |
1991 | strcpy(comm, "<...>"); | |
1992 | return; | |
1993 | } | |
bc0c38d1 | 1994 | |
939c7a4f | 1995 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1996 | if (map != NO_CMDLINE_MAP) |
e09e2867 | 1997 | strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN); |
50d88758 TG |
1998 | else |
1999 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
2000 | } |
2001 | ||
2002 | void trace_find_cmdline(int pid, char comm[]) | |
2003 | { | |
2004 | preempt_disable(); | |
2005 | arch_spin_lock(&trace_cmdline_lock); | |
2006 | ||
2007 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 2008 | |
0199c4e6 | 2009 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 2010 | preempt_enable(); |
bc0c38d1 SR |
2011 | } |
2012 | ||
d914ba37 JF |
2013 | int trace_find_tgid(int pid) |
2014 | { | |
2015 | if (unlikely(!tgid_map || !pid || pid > PID_MAX_DEFAULT)) | |
2016 | return 0; | |
2017 | ||
2018 | return tgid_map[pid]; | |
2019 | } | |
2020 | ||
2021 | static int trace_save_tgid(struct task_struct *tsk) | |
2022 | { | |
bd45d34d JF |
2023 | /* treat recording of idle task as a success */ |
2024 | if (!tsk->pid) | |
2025 | return 1; | |
2026 | ||
2027 | if (unlikely(!tgid_map || tsk->pid > PID_MAX_DEFAULT)) | |
d914ba37 JF |
2028 | return 0; |
2029 | ||
2030 | tgid_map[tsk->pid] = tsk->tgid; | |
2031 | return 1; | |
2032 | } | |
2033 | ||
2034 | static bool tracing_record_taskinfo_skip(int flags) | |
2035 | { | |
2036 | if (unlikely(!(flags & (TRACE_RECORD_CMDLINE | TRACE_RECORD_TGID)))) | |
2037 | return true; | |
2038 | if (atomic_read(&trace_record_taskinfo_disabled) || !tracing_is_on()) | |
2039 | return true; | |
2040 | if (!__this_cpu_read(trace_taskinfo_save)) | |
2041 | return true; | |
2042 | return false; | |
2043 | } | |
2044 | ||
2045 | /** | |
2046 | * tracing_record_taskinfo - record the task info of a task | |
2047 | * | |
2048 | * @task - task to record | |
2049 | * @flags - TRACE_RECORD_CMDLINE for recording comm | |
2050 | * - TRACE_RECORD_TGID for recording tgid | |
2051 | */ | |
2052 | void tracing_record_taskinfo(struct task_struct *task, int flags) | |
2053 | { | |
29b1a8ad JF |
2054 | bool done; |
2055 | ||
d914ba37 JF |
2056 | if (tracing_record_taskinfo_skip(flags)) |
2057 | return; | |
29b1a8ad JF |
2058 | |
2059 | /* | |
2060 | * Record as much task information as possible. If some fail, continue | |
2061 | * to try to record the others. | |
2062 | */ | |
2063 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(task); | |
2064 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(task); | |
2065 | ||
2066 | /* If recording any information failed, retry again soon. */ | |
2067 | if (!done) | |
d914ba37 JF |
2068 | return; |
2069 | ||
2070 | __this_cpu_write(trace_taskinfo_save, false); | |
2071 | } | |
2072 | ||
2073 | /** | |
2074 | * tracing_record_taskinfo_sched_switch - record task info for sched_switch | |
2075 | * | |
2076 | * @prev - previous task during sched_switch | |
2077 | * @next - next task during sched_switch | |
2078 | * @flags - TRACE_RECORD_CMDLINE for recording comm | |
2079 | * TRACE_RECORD_TGID for recording tgid | |
2080 | */ | |
2081 | void tracing_record_taskinfo_sched_switch(struct task_struct *prev, | |
2082 | struct task_struct *next, int flags) | |
bc0c38d1 | 2083 | { |
29b1a8ad JF |
2084 | bool done; |
2085 | ||
d914ba37 JF |
2086 | if (tracing_record_taskinfo_skip(flags)) |
2087 | return; | |
2088 | ||
29b1a8ad JF |
2089 | /* |
2090 | * Record as much task information as possible. If some fail, continue | |
2091 | * to try to record the others. | |
2092 | */ | |
2093 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(prev); | |
2094 | done &= !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(next); | |
2095 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(prev); | |
2096 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(next); | |
bc0c38d1 | 2097 | |
29b1a8ad JF |
2098 | /* If recording any information failed, retry again soon. */ |
2099 | if (!done) | |
7ffbd48d SR |
2100 | return; |
2101 | ||
d914ba37 JF |
2102 | __this_cpu_write(trace_taskinfo_save, false); |
2103 | } | |
2104 | ||
2105 | /* Helpers to record a specific task information */ | |
2106 | void tracing_record_cmdline(struct task_struct *task) | |
2107 | { | |
2108 | tracing_record_taskinfo(task, TRACE_RECORD_CMDLINE); | |
2109 | } | |
2110 | ||
2111 | void tracing_record_tgid(struct task_struct *task) | |
2112 | { | |
2113 | tracing_record_taskinfo(task, TRACE_RECORD_TGID); | |
bc0c38d1 SR |
2114 | } |
2115 | ||
af0009fc SRV |
2116 | /* |
2117 | * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq | |
2118 | * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function | |
2119 | * simplifies those functions and keeps them in sync. | |
2120 | */ | |
2121 | enum print_line_t trace_handle_return(struct trace_seq *s) | |
2122 | { | |
2123 | return trace_seq_has_overflowed(s) ? | |
2124 | TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED; | |
2125 | } | |
2126 | EXPORT_SYMBOL_GPL(trace_handle_return); | |
2127 | ||
45dcd8b8 | 2128 | void |
38697053 SR |
2129 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
2130 | int pc) | |
bc0c38d1 SR |
2131 | { |
2132 | struct task_struct *tsk = current; | |
bc0c38d1 | 2133 | |
777e208d SR |
2134 | entry->preempt_count = pc & 0xff; |
2135 | entry->pid = (tsk) ? tsk->pid : 0; | |
2136 | entry->flags = | |
9244489a | 2137 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 2138 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
2139 | #else |
2140 | TRACE_FLAG_IRQS_NOSUPPORT | | |
2141 | #endif | |
7e6867bf | 2142 | ((pc & NMI_MASK ) ? TRACE_FLAG_NMI : 0) | |
bc0c38d1 | 2143 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
c59f29cb | 2144 | ((pc & SOFTIRQ_OFFSET) ? TRACE_FLAG_SOFTIRQ : 0) | |
e5137b50 PZ |
2145 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
2146 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 2147 | } |
f413cdb8 | 2148 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 2149 | |
e77405ad SR |
2150 | struct ring_buffer_event * |
2151 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
2152 | int type, | |
2153 | unsigned long len, | |
2154 | unsigned long flags, int pc) | |
51a763dd | 2155 | { |
3e9a8aad | 2156 | return __trace_buffer_lock_reserve(buffer, type, len, flags, pc); |
0fc1b09f SRRH |
2157 | } |
2158 | ||
2159 | DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); | |
2160 | DEFINE_PER_CPU(int, trace_buffered_event_cnt); | |
2161 | static int trace_buffered_event_ref; | |
2162 | ||
2163 | /** | |
2164 | * trace_buffered_event_enable - enable buffering events | |
2165 | * | |
2166 | * When events are being filtered, it is quicker to use a temporary | |
2167 | * buffer to write the event data into if there's a likely chance | |
2168 | * that it will not be committed. The discard of the ring buffer | |
2169 | * is not as fast as committing, and is much slower than copying | |
2170 | * a commit. | |
2171 | * | |
2172 | * When an event is to be filtered, allocate per cpu buffers to | |
2173 | * write the event data into, and if the event is filtered and discarded | |
2174 | * it is simply dropped, otherwise, the entire data is to be committed | |
2175 | * in one shot. | |
2176 | */ | |
2177 | void trace_buffered_event_enable(void) | |
2178 | { | |
2179 | struct ring_buffer_event *event; | |
2180 | struct page *page; | |
2181 | int cpu; | |
51a763dd | 2182 | |
0fc1b09f SRRH |
2183 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); |
2184 | ||
2185 | if (trace_buffered_event_ref++) | |
2186 | return; | |
2187 | ||
2188 | for_each_tracing_cpu(cpu) { | |
2189 | page = alloc_pages_node(cpu_to_node(cpu), | |
2190 | GFP_KERNEL | __GFP_NORETRY, 0); | |
2191 | if (!page) | |
2192 | goto failed; | |
2193 | ||
2194 | event = page_address(page); | |
2195 | memset(event, 0, sizeof(*event)); | |
2196 | ||
2197 | per_cpu(trace_buffered_event, cpu) = event; | |
2198 | ||
2199 | preempt_disable(); | |
2200 | if (cpu == smp_processor_id() && | |
2201 | this_cpu_read(trace_buffered_event) != | |
2202 | per_cpu(trace_buffered_event, cpu)) | |
2203 | WARN_ON_ONCE(1); | |
2204 | preempt_enable(); | |
51a763dd ACM |
2205 | } |
2206 | ||
0fc1b09f SRRH |
2207 | return; |
2208 | failed: | |
2209 | trace_buffered_event_disable(); | |
2210 | } | |
2211 | ||
2212 | static void enable_trace_buffered_event(void *data) | |
2213 | { | |
2214 | /* Probably not needed, but do it anyway */ | |
2215 | smp_rmb(); | |
2216 | this_cpu_dec(trace_buffered_event_cnt); | |
2217 | } | |
2218 | ||
2219 | static void disable_trace_buffered_event(void *data) | |
2220 | { | |
2221 | this_cpu_inc(trace_buffered_event_cnt); | |
2222 | } | |
2223 | ||
2224 | /** | |
2225 | * trace_buffered_event_disable - disable buffering events | |
2226 | * | |
2227 | * When a filter is removed, it is faster to not use the buffered | |
2228 | * events, and to commit directly into the ring buffer. Free up | |
2229 | * the temp buffers when there are no more users. This requires | |
2230 | * special synchronization with current events. | |
2231 | */ | |
2232 | void trace_buffered_event_disable(void) | |
2233 | { | |
2234 | int cpu; | |
2235 | ||
2236 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); | |
2237 | ||
2238 | if (WARN_ON_ONCE(!trace_buffered_event_ref)) | |
2239 | return; | |
2240 | ||
2241 | if (--trace_buffered_event_ref) | |
2242 | return; | |
2243 | ||
2244 | preempt_disable(); | |
2245 | /* For each CPU, set the buffer as used. */ | |
2246 | smp_call_function_many(tracing_buffer_mask, | |
2247 | disable_trace_buffered_event, NULL, 1); | |
2248 | preempt_enable(); | |
2249 | ||
2250 | /* Wait for all current users to finish */ | |
2251 | synchronize_sched(); | |
2252 | ||
2253 | for_each_tracing_cpu(cpu) { | |
2254 | free_page((unsigned long)per_cpu(trace_buffered_event, cpu)); | |
2255 | per_cpu(trace_buffered_event, cpu) = NULL; | |
2256 | } | |
2257 | /* | |
2258 | * Make sure trace_buffered_event is NULL before clearing | |
2259 | * trace_buffered_event_cnt. | |
2260 | */ | |
2261 | smp_wmb(); | |
2262 | ||
2263 | preempt_disable(); | |
2264 | /* Do the work on each cpu */ | |
2265 | smp_call_function_many(tracing_buffer_mask, | |
2266 | enable_trace_buffered_event, NULL, 1); | |
2267 | preempt_enable(); | |
51a763dd | 2268 | } |
51a763dd | 2269 | |
2c4a33ab SRRH |
2270 | static struct ring_buffer *temp_buffer; |
2271 | ||
ccb469a1 SR |
2272 | struct ring_buffer_event * |
2273 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
7f1d2f82 | 2274 | struct trace_event_file *trace_file, |
ccb469a1 SR |
2275 | int type, unsigned long len, |
2276 | unsigned long flags, int pc) | |
2277 | { | |
2c4a33ab | 2278 | struct ring_buffer_event *entry; |
0fc1b09f | 2279 | int val; |
2c4a33ab | 2280 | |
7f1d2f82 | 2281 | *current_rb = trace_file->tr->trace_buffer.buffer; |
0fc1b09f SRRH |
2282 | |
2283 | if ((trace_file->flags & | |
2284 | (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && | |
2285 | (entry = this_cpu_read(trace_buffered_event))) { | |
2286 | /* Try to use the per cpu buffer first */ | |
2287 | val = this_cpu_inc_return(trace_buffered_event_cnt); | |
2288 | if (val == 1) { | |
2289 | trace_event_setup(entry, type, flags, pc); | |
2290 | entry->array[0] = len; | |
2291 | return entry; | |
2292 | } | |
2293 | this_cpu_dec(trace_buffered_event_cnt); | |
2294 | } | |
2295 | ||
3e9a8aad SRRH |
2296 | entry = __trace_buffer_lock_reserve(*current_rb, |
2297 | type, len, flags, pc); | |
2c4a33ab SRRH |
2298 | /* |
2299 | * If tracing is off, but we have triggers enabled | |
2300 | * we still need to look at the event data. Use the temp_buffer | |
2301 | * to store the trace event for the tigger to use. It's recusive | |
2302 | * safe and will not be recorded anywhere. | |
2303 | */ | |
5d6ad960 | 2304 | if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { |
2c4a33ab | 2305 | *current_rb = temp_buffer; |
3e9a8aad SRRH |
2306 | entry = __trace_buffer_lock_reserve(*current_rb, |
2307 | type, len, flags, pc); | |
2c4a33ab SRRH |
2308 | } |
2309 | return entry; | |
ccb469a1 SR |
2310 | } |
2311 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
2312 | ||
42391745 SRRH |
2313 | static DEFINE_SPINLOCK(tracepoint_iter_lock); |
2314 | static DEFINE_MUTEX(tracepoint_printk_mutex); | |
2315 | ||
2316 | static void output_printk(struct trace_event_buffer *fbuffer) | |
2317 | { | |
2318 | struct trace_event_call *event_call; | |
2319 | struct trace_event *event; | |
2320 | unsigned long flags; | |
2321 | struct trace_iterator *iter = tracepoint_print_iter; | |
2322 | ||
2323 | /* We should never get here if iter is NULL */ | |
2324 | if (WARN_ON_ONCE(!iter)) | |
2325 | return; | |
2326 | ||
2327 | event_call = fbuffer->trace_file->event_call; | |
2328 | if (!event_call || !event_call->event.funcs || | |
2329 | !event_call->event.funcs->trace) | |
2330 | return; | |
2331 | ||
2332 | event = &fbuffer->trace_file->event_call->event; | |
2333 | ||
2334 | spin_lock_irqsave(&tracepoint_iter_lock, flags); | |
2335 | trace_seq_init(&iter->seq); | |
2336 | iter->ent = fbuffer->entry; | |
2337 | event_call->event.funcs->trace(iter, 0, event); | |
2338 | trace_seq_putc(&iter->seq, 0); | |
2339 | printk("%s", iter->seq.buffer); | |
2340 | ||
2341 | spin_unlock_irqrestore(&tracepoint_iter_lock, flags); | |
2342 | } | |
2343 | ||
2344 | int tracepoint_printk_sysctl(struct ctl_table *table, int write, | |
2345 | void __user *buffer, size_t *lenp, | |
2346 | loff_t *ppos) | |
2347 | { | |
2348 | int save_tracepoint_printk; | |
2349 | int ret; | |
2350 | ||
2351 | mutex_lock(&tracepoint_printk_mutex); | |
2352 | save_tracepoint_printk = tracepoint_printk; | |
2353 | ||
2354 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
2355 | ||
2356 | /* | |
2357 | * This will force exiting early, as tracepoint_printk | |
2358 | * is always zero when tracepoint_printk_iter is not allocated | |
2359 | */ | |
2360 | if (!tracepoint_print_iter) | |
2361 | tracepoint_printk = 0; | |
2362 | ||
2363 | if (save_tracepoint_printk == tracepoint_printk) | |
2364 | goto out; | |
2365 | ||
2366 | if (tracepoint_printk) | |
2367 | static_key_enable(&tracepoint_printk_key.key); | |
2368 | else | |
2369 | static_key_disable(&tracepoint_printk_key.key); | |
2370 | ||
2371 | out: | |
2372 | mutex_unlock(&tracepoint_printk_mutex); | |
2373 | ||
2374 | return ret; | |
2375 | } | |
2376 | ||
2377 | void trace_event_buffer_commit(struct trace_event_buffer *fbuffer) | |
2378 | { | |
2379 | if (static_key_false(&tracepoint_printk_key.key)) | |
2380 | output_printk(fbuffer); | |
2381 | ||
2382 | event_trigger_unlock_commit(fbuffer->trace_file, fbuffer->buffer, | |
2383 | fbuffer->event, fbuffer->entry, | |
2384 | fbuffer->flags, fbuffer->pc); | |
2385 | } | |
2386 | EXPORT_SYMBOL_GPL(trace_event_buffer_commit); | |
2387 | ||
b7f0c959 SRRH |
2388 | void trace_buffer_unlock_commit_regs(struct trace_array *tr, |
2389 | struct ring_buffer *buffer, | |
0d5c6e1c SR |
2390 | struct ring_buffer_event *event, |
2391 | unsigned long flags, int pc, | |
2392 | struct pt_regs *regs) | |
1fd8df2c | 2393 | { |
7ffbd48d | 2394 | __buffer_unlock_commit(buffer, event); |
1fd8df2c | 2395 | |
be54f69c SRRH |
2396 | /* |
2397 | * If regs is not set, then skip the following callers: | |
2398 | * trace_buffer_unlock_commit_regs | |
2399 | * event_trigger_unlock_commit | |
2400 | * trace_event_buffer_commit | |
2401 | * trace_event_raw_event_sched_switch | |
2402 | * Note, we can still get here via blktrace, wakeup tracer | |
2403 | * and mmiotrace, but that's ok if they lose a function or | |
2404 | * two. They are that meaningful. | |
2405 | */ | |
2406 | ftrace_trace_stack(tr, buffer, flags, regs ? 0 : 4, pc, regs); | |
1fd8df2c MH |
2407 | ftrace_trace_userstack(buffer, flags, pc); |
2408 | } | |
1fd8df2c | 2409 | |
52ffabe3 SRRH |
2410 | /* |
2411 | * Similar to trace_buffer_unlock_commit_regs() but do not dump stack. | |
2412 | */ | |
2413 | void | |
2414 | trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer, | |
2415 | struct ring_buffer_event *event) | |
2416 | { | |
2417 | __buffer_unlock_commit(buffer, event); | |
2418 | } | |
2419 | ||
478409dd CZ |
2420 | static void |
2421 | trace_process_export(struct trace_export *export, | |
2422 | struct ring_buffer_event *event) | |
2423 | { | |
2424 | struct trace_entry *entry; | |
2425 | unsigned int size = 0; | |
2426 | ||
2427 | entry = ring_buffer_event_data(event); | |
2428 | size = ring_buffer_event_length(event); | |
2429 | export->write(entry, size); | |
2430 | } | |
2431 | ||
2432 | static DEFINE_MUTEX(ftrace_export_lock); | |
2433 | ||
2434 | static struct trace_export __rcu *ftrace_exports_list __read_mostly; | |
2435 | ||
2436 | static DEFINE_STATIC_KEY_FALSE(ftrace_exports_enabled); | |
2437 | ||
2438 | static inline void ftrace_exports_enable(void) | |
2439 | { | |
2440 | static_branch_enable(&ftrace_exports_enabled); | |
2441 | } | |
2442 | ||
2443 | static inline void ftrace_exports_disable(void) | |
2444 | { | |
2445 | static_branch_disable(&ftrace_exports_enabled); | |
2446 | } | |
2447 | ||
2448 | void ftrace_exports(struct ring_buffer_event *event) | |
2449 | { | |
2450 | struct trace_export *export; | |
2451 | ||
2452 | preempt_disable_notrace(); | |
2453 | ||
2454 | export = rcu_dereference_raw_notrace(ftrace_exports_list); | |
2455 | while (export) { | |
2456 | trace_process_export(export, event); | |
2457 | export = rcu_dereference_raw_notrace(export->next); | |
2458 | } | |
2459 | ||
2460 | preempt_enable_notrace(); | |
2461 | } | |
2462 | ||
2463 | static inline void | |
2464 | add_trace_export(struct trace_export **list, struct trace_export *export) | |
2465 | { | |
2466 | rcu_assign_pointer(export->next, *list); | |
2467 | /* | |
2468 | * We are entering export into the list but another | |
2469 | * CPU might be walking that list. We need to make sure | |
2470 | * the export->next pointer is valid before another CPU sees | |
2471 | * the export pointer included into the list. | |
2472 | */ | |
2473 | rcu_assign_pointer(*list, export); | |
2474 | } | |
2475 | ||
2476 | static inline int | |
2477 | rm_trace_export(struct trace_export **list, struct trace_export *export) | |
2478 | { | |
2479 | struct trace_export **p; | |
2480 | ||
2481 | for (p = list; *p != NULL; p = &(*p)->next) | |
2482 | if (*p == export) | |
2483 | break; | |
2484 | ||
2485 | if (*p != export) | |
2486 | return -1; | |
2487 | ||
2488 | rcu_assign_pointer(*p, (*p)->next); | |
2489 | ||
2490 | return 0; | |
2491 | } | |
2492 | ||
2493 | static inline void | |
2494 | add_ftrace_export(struct trace_export **list, struct trace_export *export) | |
2495 | { | |
2496 | if (*list == NULL) | |
2497 | ftrace_exports_enable(); | |
2498 | ||
2499 | add_trace_export(list, export); | |
2500 | } | |
2501 | ||
2502 | static inline int | |
2503 | rm_ftrace_export(struct trace_export **list, struct trace_export *export) | |
2504 | { | |
2505 | int ret; | |
2506 | ||
2507 | ret = rm_trace_export(list, export); | |
2508 | if (*list == NULL) | |
2509 | ftrace_exports_disable(); | |
2510 | ||
2511 | return ret; | |
2512 | } | |
2513 | ||
2514 | int register_ftrace_export(struct trace_export *export) | |
2515 | { | |
2516 | if (WARN_ON_ONCE(!export->write)) | |
2517 | return -1; | |
2518 | ||
2519 | mutex_lock(&ftrace_export_lock); | |
2520 | ||
2521 | add_ftrace_export(&ftrace_exports_list, export); | |
2522 | ||
2523 | mutex_unlock(&ftrace_export_lock); | |
2524 | ||
2525 | return 0; | |
2526 | } | |
2527 | EXPORT_SYMBOL_GPL(register_ftrace_export); | |
2528 | ||
2529 | int unregister_ftrace_export(struct trace_export *export) | |
2530 | { | |
2531 | int ret; | |
2532 | ||
2533 | mutex_lock(&ftrace_export_lock); | |
2534 | ||
2535 | ret = rm_ftrace_export(&ftrace_exports_list, export); | |
2536 | ||
2537 | mutex_unlock(&ftrace_export_lock); | |
2538 | ||
2539 | return ret; | |
2540 | } | |
2541 | EXPORT_SYMBOL_GPL(unregister_ftrace_export); | |
2542 | ||
e309b41d | 2543 | void |
7be42151 | 2544 | trace_function(struct trace_array *tr, |
38697053 SR |
2545 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
2546 | int pc) | |
bc0c38d1 | 2547 | { |
2425bcb9 | 2548 | struct trace_event_call *call = &event_function; |
12883efb | 2549 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 2550 | struct ring_buffer_event *event; |
777e208d | 2551 | struct ftrace_entry *entry; |
bc0c38d1 | 2552 | |
3e9a8aad SRRH |
2553 | event = __trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
2554 | flags, pc); | |
3928a8a2 SR |
2555 | if (!event) |
2556 | return; | |
2557 | entry = ring_buffer_event_data(event); | |
777e208d SR |
2558 | entry->ip = ip; |
2559 | entry->parent_ip = parent_ip; | |
e1112b4d | 2560 | |
478409dd CZ |
2561 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
2562 | if (static_branch_unlikely(&ftrace_exports_enabled)) | |
2563 | ftrace_exports(event); | |
7ffbd48d | 2564 | __buffer_unlock_commit(buffer, event); |
478409dd | 2565 | } |
bc0c38d1 SR |
2566 | } |
2567 | ||
c0a0d0d3 | 2568 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
2569 | |
2570 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
2571 | struct ftrace_stack { | |
2572 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
2573 | }; | |
2574 | ||
2575 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
2576 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
2577 | ||
e77405ad | 2578 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 2579 | unsigned long flags, |
1fd8df2c | 2580 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 2581 | { |
2425bcb9 | 2582 | struct trace_event_call *call = &event_kernel_stack; |
3928a8a2 | 2583 | struct ring_buffer_event *event; |
777e208d | 2584 | struct stack_entry *entry; |
86387f7e | 2585 | struct stack_trace trace; |
4a9bd3f1 SR |
2586 | int use_stack; |
2587 | int size = FTRACE_STACK_ENTRIES; | |
2588 | ||
2589 | trace.nr_entries = 0; | |
2590 | trace.skip = skip; | |
2591 | ||
be54f69c SRRH |
2592 | /* |
2593 | * Add two, for this function and the call to save_stack_trace() | |
2594 | * If regs is set, then these functions will not be in the way. | |
2595 | */ | |
2596 | if (!regs) | |
2597 | trace.skip += 2; | |
2598 | ||
4a9bd3f1 SR |
2599 | /* |
2600 | * Since events can happen in NMIs there's no safe way to | |
2601 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
2602 | * or NMI comes in, it will just have to use the default | |
2603 | * FTRACE_STACK_SIZE. | |
2604 | */ | |
2605 | preempt_disable_notrace(); | |
2606 | ||
82146529 | 2607 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
2608 | /* |
2609 | * We don't need any atomic variables, just a barrier. | |
2610 | * If an interrupt comes in, we don't care, because it would | |
2611 | * have exited and put the counter back to what we want. | |
2612 | * We just need a barrier to keep gcc from moving things | |
2613 | * around. | |
2614 | */ | |
2615 | barrier(); | |
2616 | if (use_stack == 1) { | |
bdffd893 | 2617 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
2618 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
2619 | ||
2620 | if (regs) | |
2621 | save_stack_trace_regs(regs, &trace); | |
2622 | else | |
2623 | save_stack_trace(&trace); | |
2624 | ||
2625 | if (trace.nr_entries > size) | |
2626 | size = trace.nr_entries; | |
2627 | } else | |
2628 | /* From now on, use_stack is a boolean */ | |
2629 | use_stack = 0; | |
2630 | ||
2631 | size *= sizeof(unsigned long); | |
86387f7e | 2632 | |
3e9a8aad SRRH |
2633 | event = __trace_buffer_lock_reserve(buffer, TRACE_STACK, |
2634 | sizeof(*entry) + size, flags, pc); | |
3928a8a2 | 2635 | if (!event) |
4a9bd3f1 SR |
2636 | goto out; |
2637 | entry = ring_buffer_event_data(event); | |
86387f7e | 2638 | |
4a9bd3f1 SR |
2639 | memset(&entry->caller, 0, size); |
2640 | ||
2641 | if (use_stack) | |
2642 | memcpy(&entry->caller, trace.entries, | |
2643 | trace.nr_entries * sizeof(unsigned long)); | |
2644 | else { | |
2645 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
2646 | trace.entries = entry->caller; | |
2647 | if (regs) | |
2648 | save_stack_trace_regs(regs, &trace); | |
2649 | else | |
2650 | save_stack_trace(&trace); | |
2651 | } | |
2652 | ||
2653 | entry->size = trace.nr_entries; | |
86387f7e | 2654 | |
f306cc82 | 2655 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 2656 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
2657 | |
2658 | out: | |
2659 | /* Again, don't let gcc optimize things here */ | |
2660 | barrier(); | |
82146529 | 2661 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
2662 | preempt_enable_notrace(); |
2663 | ||
f0a920d5 IM |
2664 | } |
2665 | ||
2d34f489 SRRH |
2666 | static inline void ftrace_trace_stack(struct trace_array *tr, |
2667 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
2668 | unsigned long flags, |
2669 | int skip, int pc, struct pt_regs *regs) | |
53614991 | 2670 | { |
2d34f489 | 2671 | if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) |
53614991 SR |
2672 | return; |
2673 | ||
73dddbb5 | 2674 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); |
53614991 SR |
2675 | } |
2676 | ||
c0a0d0d3 FW |
2677 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
2678 | int pc) | |
38697053 | 2679 | { |
a33d7d94 SRV |
2680 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
2681 | ||
2682 | if (rcu_is_watching()) { | |
2683 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); | |
2684 | return; | |
2685 | } | |
2686 | ||
2687 | /* | |
2688 | * When an NMI triggers, RCU is enabled via rcu_nmi_enter(), | |
2689 | * but if the above rcu_is_watching() failed, then the NMI | |
2690 | * triggered someplace critical, and rcu_irq_enter() should | |
2691 | * not be called from NMI. | |
2692 | */ | |
2693 | if (unlikely(in_nmi())) | |
2694 | return; | |
2695 | ||
2696 | /* | |
2697 | * It is possible that a function is being traced in a | |
2698 | * location that RCU is not watching. A call to | |
2699 | * rcu_irq_enter() will make sure that it is, but there's | |
2700 | * a few internal rcu functions that could be traced | |
2701 | * where that wont work either. In those cases, we just | |
2702 | * do nothing. | |
2703 | */ | |
2704 | if (unlikely(rcu_irq_enter_disabled())) | |
2705 | return; | |
2706 | ||
2707 | rcu_irq_enter_irqson(); | |
2708 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); | |
2709 | rcu_irq_exit_irqson(); | |
38697053 SR |
2710 | } |
2711 | ||
03889384 SR |
2712 | /** |
2713 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 2714 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 2715 | */ |
c142be8e | 2716 | void trace_dump_stack(int skip) |
03889384 SR |
2717 | { |
2718 | unsigned long flags; | |
2719 | ||
2720 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 2721 | return; |
03889384 SR |
2722 | |
2723 | local_save_flags(flags); | |
2724 | ||
c142be8e SRRH |
2725 | /* |
2726 | * Skip 3 more, seems to get us at the caller of | |
2727 | * this function. | |
2728 | */ | |
2729 | skip += 3; | |
2730 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
2731 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
2732 | } |
2733 | ||
91e86e56 SR |
2734 | static DEFINE_PER_CPU(int, user_stack_count); |
2735 | ||
e77405ad SR |
2736 | void |
2737 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 2738 | { |
2425bcb9 | 2739 | struct trace_event_call *call = &event_user_stack; |
8d7c6a96 | 2740 | struct ring_buffer_event *event; |
02b67518 TE |
2741 | struct userstack_entry *entry; |
2742 | struct stack_trace trace; | |
02b67518 | 2743 | |
983f938a | 2744 | if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE)) |
02b67518 TE |
2745 | return; |
2746 | ||
b6345879 SR |
2747 | /* |
2748 | * NMIs can not handle page faults, even with fix ups. | |
2749 | * The save user stack can (and often does) fault. | |
2750 | */ | |
2751 | if (unlikely(in_nmi())) | |
2752 | return; | |
02b67518 | 2753 | |
91e86e56 SR |
2754 | /* |
2755 | * prevent recursion, since the user stack tracing may | |
2756 | * trigger other kernel events. | |
2757 | */ | |
2758 | preempt_disable(); | |
2759 | if (__this_cpu_read(user_stack_count)) | |
2760 | goto out; | |
2761 | ||
2762 | __this_cpu_inc(user_stack_count); | |
2763 | ||
3e9a8aad SRRH |
2764 | event = __trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
2765 | sizeof(*entry), flags, pc); | |
02b67518 | 2766 | if (!event) |
1dbd1951 | 2767 | goto out_drop_count; |
02b67518 | 2768 | entry = ring_buffer_event_data(event); |
02b67518 | 2769 | |
48659d31 | 2770 | entry->tgid = current->tgid; |
02b67518 TE |
2771 | memset(&entry->caller, 0, sizeof(entry->caller)); |
2772 | ||
2773 | trace.nr_entries = 0; | |
2774 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
2775 | trace.skip = 0; | |
2776 | trace.entries = entry->caller; | |
2777 | ||
2778 | save_stack_trace_user(&trace); | |
f306cc82 | 2779 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 2780 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 2781 | |
1dbd1951 | 2782 | out_drop_count: |
91e86e56 | 2783 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
2784 | out: |
2785 | preempt_enable(); | |
02b67518 TE |
2786 | } |
2787 | ||
4fd27358 HE |
2788 | #ifdef UNUSED |
2789 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 2790 | { |
7be42151 | 2791 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 2792 | } |
4fd27358 | 2793 | #endif /* UNUSED */ |
02b67518 | 2794 | |
c0a0d0d3 FW |
2795 | #endif /* CONFIG_STACKTRACE */ |
2796 | ||
07d777fe SR |
2797 | /* created for use with alloc_percpu */ |
2798 | struct trace_buffer_struct { | |
e2ace001 AL |
2799 | int nesting; |
2800 | char buffer[4][TRACE_BUF_SIZE]; | |
07d777fe SR |
2801 | }; |
2802 | ||
2803 | static struct trace_buffer_struct *trace_percpu_buffer; | |
07d777fe SR |
2804 | |
2805 | /* | |
e2ace001 AL |
2806 | * Thise allows for lockless recording. If we're nested too deeply, then |
2807 | * this returns NULL. | |
07d777fe SR |
2808 | */ |
2809 | static char *get_trace_buf(void) | |
2810 | { | |
e2ace001 | 2811 | struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer); |
07d777fe | 2812 | |
e2ace001 | 2813 | if (!buffer || buffer->nesting >= 4) |
07d777fe SR |
2814 | return NULL; |
2815 | ||
3d9622c1 SRV |
2816 | buffer->nesting++; |
2817 | ||
2818 | /* Interrupts must see nesting incremented before we use the buffer */ | |
2819 | barrier(); | |
2820 | return &buffer->buffer[buffer->nesting][0]; | |
e2ace001 AL |
2821 | } |
2822 | ||
2823 | static void put_trace_buf(void) | |
2824 | { | |
3d9622c1 SRV |
2825 | /* Don't let the decrement of nesting leak before this */ |
2826 | barrier(); | |
e2ace001 | 2827 | this_cpu_dec(trace_percpu_buffer->nesting); |
07d777fe SR |
2828 | } |
2829 | ||
2830 | static int alloc_percpu_trace_buffer(void) | |
2831 | { | |
2832 | struct trace_buffer_struct *buffers; | |
07d777fe SR |
2833 | |
2834 | buffers = alloc_percpu(struct trace_buffer_struct); | |
e2ace001 AL |
2835 | if (WARN(!buffers, "Could not allocate percpu trace_printk buffer")) |
2836 | return -ENOMEM; | |
07d777fe SR |
2837 | |
2838 | trace_percpu_buffer = buffers; | |
07d777fe | 2839 | return 0; |
07d777fe SR |
2840 | } |
2841 | ||
81698831 SR |
2842 | static int buffers_allocated; |
2843 | ||
07d777fe SR |
2844 | void trace_printk_init_buffers(void) |
2845 | { | |
07d777fe SR |
2846 | if (buffers_allocated) |
2847 | return; | |
2848 | ||
2849 | if (alloc_percpu_trace_buffer()) | |
2850 | return; | |
2851 | ||
2184db46 SR |
2852 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2853 | ||
a395d6a7 JP |
2854 | pr_warn("\n"); |
2855 | pr_warn("**********************************************************\n"); | |
2856 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2857 | pr_warn("** **\n"); | |
2858 | pr_warn("** trace_printk() being used. Allocating extra memory. **\n"); | |
2859 | pr_warn("** **\n"); | |
2860 | pr_warn("** This means that this is a DEBUG kernel and it is **\n"); | |
2861 | pr_warn("** unsafe for production use. **\n"); | |
2862 | pr_warn("** **\n"); | |
2863 | pr_warn("** If you see this message and you are not debugging **\n"); | |
2864 | pr_warn("** the kernel, report this immediately to your vendor! **\n"); | |
2865 | pr_warn("** **\n"); | |
2866 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2867 | pr_warn("**********************************************************\n"); | |
07d777fe | 2868 | |
b382ede6 SR |
2869 | /* Expand the buffers to set size */ |
2870 | tracing_update_buffers(); | |
2871 | ||
07d777fe | 2872 | buffers_allocated = 1; |
81698831 SR |
2873 | |
2874 | /* | |
2875 | * trace_printk_init_buffers() can be called by modules. | |
2876 | * If that happens, then we need to start cmdline recording | |
2877 | * directly here. If the global_trace.buffer is already | |
2878 | * allocated here, then this was called by module code. | |
2879 | */ | |
12883efb | 2880 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2881 | tracing_start_cmdline_record(); |
2882 | } | |
2883 | ||
2884 | void trace_printk_start_comm(void) | |
2885 | { | |
2886 | /* Start tracing comms if trace printk is set */ | |
2887 | if (!buffers_allocated) | |
2888 | return; | |
2889 | tracing_start_cmdline_record(); | |
2890 | } | |
2891 | ||
2892 | static void trace_printk_start_stop_comm(int enabled) | |
2893 | { | |
2894 | if (!buffers_allocated) | |
2895 | return; | |
2896 | ||
2897 | if (enabled) | |
2898 | tracing_start_cmdline_record(); | |
2899 | else | |
2900 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2901 | } |
2902 | ||
769b0441 | 2903 | /** |
48ead020 | 2904 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2905 | * |
2906 | */ | |
40ce74f1 | 2907 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2908 | { |
2425bcb9 | 2909 | struct trace_event_call *call = &event_bprint; |
769b0441 | 2910 | struct ring_buffer_event *event; |
e77405ad | 2911 | struct ring_buffer *buffer; |
769b0441 | 2912 | struct trace_array *tr = &global_trace; |
48ead020 | 2913 | struct bprint_entry *entry; |
769b0441 | 2914 | unsigned long flags; |
07d777fe SR |
2915 | char *tbuffer; |
2916 | int len = 0, size, pc; | |
769b0441 FW |
2917 | |
2918 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2919 | return 0; | |
2920 | ||
2921 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2922 | pause_graph_tracing(); | |
2923 | ||
2924 | pc = preempt_count(); | |
5168ae50 | 2925 | preempt_disable_notrace(); |
769b0441 | 2926 | |
07d777fe SR |
2927 | tbuffer = get_trace_buf(); |
2928 | if (!tbuffer) { | |
2929 | len = 0; | |
e2ace001 | 2930 | goto out_nobuffer; |
07d777fe | 2931 | } |
769b0441 | 2932 | |
07d777fe | 2933 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2934 | |
07d777fe SR |
2935 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2936 | goto out; | |
769b0441 | 2937 | |
07d777fe | 2938 | local_save_flags(flags); |
769b0441 | 2939 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2940 | buffer = tr->trace_buffer.buffer; |
3e9a8aad SRRH |
2941 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2942 | flags, pc); | |
769b0441 | 2943 | if (!event) |
07d777fe | 2944 | goto out; |
769b0441 FW |
2945 | entry = ring_buffer_event_data(event); |
2946 | entry->ip = ip; | |
769b0441 FW |
2947 | entry->fmt = fmt; |
2948 | ||
07d777fe | 2949 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2950 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2951 | __buffer_unlock_commit(buffer, event); |
2d34f489 | 2952 | ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); |
d931369b | 2953 | } |
769b0441 | 2954 | |
769b0441 | 2955 | out: |
e2ace001 AL |
2956 | put_trace_buf(); |
2957 | ||
2958 | out_nobuffer: | |
5168ae50 | 2959 | preempt_enable_notrace(); |
769b0441 FW |
2960 | unpause_graph_tracing(); |
2961 | ||
2962 | return len; | |
2963 | } | |
48ead020 FW |
2964 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2965 | ||
017fe62b | 2966 | __printf(3, 0) |
12883efb SRRH |
2967 | static int |
2968 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2969 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2970 | { |
2425bcb9 | 2971 | struct trace_event_call *call = &event_print; |
48ead020 | 2972 | struct ring_buffer_event *event; |
07d777fe | 2973 | int len = 0, size, pc; |
48ead020 | 2974 | struct print_entry *entry; |
07d777fe SR |
2975 | unsigned long flags; |
2976 | char *tbuffer; | |
48ead020 FW |
2977 | |
2978 | if (tracing_disabled || tracing_selftest_running) | |
2979 | return 0; | |
2980 | ||
07d777fe SR |
2981 | /* Don't pollute graph traces with trace_vprintk internals */ |
2982 | pause_graph_tracing(); | |
2983 | ||
48ead020 FW |
2984 | pc = preempt_count(); |
2985 | preempt_disable_notrace(); | |
48ead020 | 2986 | |
07d777fe SR |
2987 | |
2988 | tbuffer = get_trace_buf(); | |
2989 | if (!tbuffer) { | |
2990 | len = 0; | |
e2ace001 | 2991 | goto out_nobuffer; |
07d777fe | 2992 | } |
48ead020 | 2993 | |
3558a5ac | 2994 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 | 2995 | |
07d777fe | 2996 | local_save_flags(flags); |
48ead020 | 2997 | size = sizeof(*entry) + len + 1; |
3e9a8aad SRRH |
2998 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
2999 | flags, pc); | |
48ead020 | 3000 | if (!event) |
07d777fe | 3001 | goto out; |
48ead020 | 3002 | entry = ring_buffer_event_data(event); |
c13d2f7c | 3003 | entry->ip = ip; |
48ead020 | 3004 | |
3558a5ac | 3005 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 3006 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 3007 | __buffer_unlock_commit(buffer, event); |
2d34f489 | 3008 | ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL); |
d931369b | 3009 | } |
e2ace001 AL |
3010 | |
3011 | out: | |
3012 | put_trace_buf(); | |
3013 | ||
3014 | out_nobuffer: | |
48ead020 | 3015 | preempt_enable_notrace(); |
07d777fe | 3016 | unpause_graph_tracing(); |
48ead020 FW |
3017 | |
3018 | return len; | |
3019 | } | |
659372d3 | 3020 | |
017fe62b | 3021 | __printf(3, 0) |
12883efb SRRH |
3022 | int trace_array_vprintk(struct trace_array *tr, |
3023 | unsigned long ip, const char *fmt, va_list args) | |
3024 | { | |
3025 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
3026 | } | |
3027 | ||
017fe62b | 3028 | __printf(3, 0) |
12883efb SRRH |
3029 | int trace_array_printk(struct trace_array *tr, |
3030 | unsigned long ip, const char *fmt, ...) | |
3031 | { | |
3032 | int ret; | |
3033 | va_list ap; | |
3034 | ||
983f938a | 3035 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
3036 | return 0; |
3037 | ||
3038 | va_start(ap, fmt); | |
3039 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
3040 | va_end(ap); | |
3041 | return ret; | |
3042 | } | |
3043 | ||
017fe62b | 3044 | __printf(3, 4) |
12883efb SRRH |
3045 | int trace_array_printk_buf(struct ring_buffer *buffer, |
3046 | unsigned long ip, const char *fmt, ...) | |
3047 | { | |
3048 | int ret; | |
3049 | va_list ap; | |
3050 | ||
983f938a | 3051 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
3052 | return 0; |
3053 | ||
3054 | va_start(ap, fmt); | |
3055 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
3056 | va_end(ap); | |
3057 | return ret; | |
3058 | } | |
3059 | ||
017fe62b | 3060 | __printf(2, 0) |
659372d3 SR |
3061 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
3062 | { | |
a813a159 | 3063 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 3064 | } |
769b0441 FW |
3065 | EXPORT_SYMBOL_GPL(trace_vprintk); |
3066 | ||
e2ac8ef5 | 3067 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 3068 | { |
6d158a81 SR |
3069 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
3070 | ||
5a90f577 | 3071 | iter->idx++; |
6d158a81 SR |
3072 | if (buf_iter) |
3073 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
3074 | } |
3075 | ||
e309b41d | 3076 | static struct trace_entry * |
bc21b478 SR |
3077 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
3078 | unsigned long *lost_events) | |
dd0e545f | 3079 | { |
3928a8a2 | 3080 | struct ring_buffer_event *event; |
6d158a81 | 3081 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 3082 | |
d769041f SR |
3083 | if (buf_iter) |
3084 | event = ring_buffer_iter_peek(buf_iter, ts); | |
3085 | else | |
12883efb | 3086 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 3087 | lost_events); |
d769041f | 3088 | |
4a9bd3f1 SR |
3089 | if (event) { |
3090 | iter->ent_size = ring_buffer_event_length(event); | |
3091 | return ring_buffer_event_data(event); | |
3092 | } | |
3093 | iter->ent_size = 0; | |
3094 | return NULL; | |
dd0e545f | 3095 | } |
d769041f | 3096 | |
dd0e545f | 3097 | static struct trace_entry * |
bc21b478 SR |
3098 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
3099 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 3100 | { |
12883efb | 3101 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 3102 | struct trace_entry *ent, *next = NULL; |
aa27497c | 3103 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 3104 | int cpu_file = iter->cpu_file; |
3928a8a2 | 3105 | u64 next_ts = 0, ts; |
bc0c38d1 | 3106 | int next_cpu = -1; |
12b5da34 | 3107 | int next_size = 0; |
bc0c38d1 SR |
3108 | int cpu; |
3109 | ||
b04cc6b1 FW |
3110 | /* |
3111 | * If we are in a per_cpu trace file, don't bother by iterating over | |
3112 | * all cpu and peek directly. | |
3113 | */ | |
ae3b5093 | 3114 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
3115 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
3116 | return NULL; | |
bc21b478 | 3117 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
3118 | if (ent_cpu) |
3119 | *ent_cpu = cpu_file; | |
3120 | ||
3121 | return ent; | |
3122 | } | |
3123 | ||
ab46428c | 3124 | for_each_tracing_cpu(cpu) { |
dd0e545f | 3125 | |
3928a8a2 SR |
3126 | if (ring_buffer_empty_cpu(buffer, cpu)) |
3127 | continue; | |
dd0e545f | 3128 | |
bc21b478 | 3129 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 3130 | |
cdd31cd2 IM |
3131 | /* |
3132 | * Pick the entry with the smallest timestamp: | |
3133 | */ | |
3928a8a2 | 3134 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
3135 | next = ent; |
3136 | next_cpu = cpu; | |
3928a8a2 | 3137 | next_ts = ts; |
bc21b478 | 3138 | next_lost = lost_events; |
12b5da34 | 3139 | next_size = iter->ent_size; |
bc0c38d1 SR |
3140 | } |
3141 | } | |
3142 | ||
12b5da34 SR |
3143 | iter->ent_size = next_size; |
3144 | ||
bc0c38d1 SR |
3145 | if (ent_cpu) |
3146 | *ent_cpu = next_cpu; | |
3147 | ||
3928a8a2 SR |
3148 | if (ent_ts) |
3149 | *ent_ts = next_ts; | |
3150 | ||
bc21b478 SR |
3151 | if (missing_events) |
3152 | *missing_events = next_lost; | |
3153 | ||
bc0c38d1 SR |
3154 | return next; |
3155 | } | |
3156 | ||
dd0e545f | 3157 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
3158 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
3159 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 3160 | { |
bc21b478 | 3161 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
3162 | } |
3163 | ||
3164 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 3165 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 3166 | { |
bc21b478 SR |
3167 | iter->ent = __find_next_entry(iter, &iter->cpu, |
3168 | &iter->lost_events, &iter->ts); | |
dd0e545f | 3169 | |
3928a8a2 | 3170 | if (iter->ent) |
e2ac8ef5 | 3171 | trace_iterator_increment(iter); |
dd0e545f | 3172 | |
3928a8a2 | 3173 | return iter->ent ? iter : NULL; |
b3806b43 | 3174 | } |
bc0c38d1 | 3175 | |
e309b41d | 3176 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 3177 | { |
12883efb | 3178 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 3179 | &iter->lost_events); |
bc0c38d1 SR |
3180 | } |
3181 | ||
e309b41d | 3182 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
3183 | { |
3184 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 3185 | int i = (int)*pos; |
4e3c3333 | 3186 | void *ent; |
bc0c38d1 | 3187 | |
a63ce5b3 SR |
3188 | WARN_ON_ONCE(iter->leftover); |
3189 | ||
bc0c38d1 SR |
3190 | (*pos)++; |
3191 | ||
3192 | /* can't go backwards */ | |
3193 | if (iter->idx > i) | |
3194 | return NULL; | |
3195 | ||
3196 | if (iter->idx < 0) | |
955b61e5 | 3197 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
3198 | else |
3199 | ent = iter; | |
3200 | ||
3201 | while (ent && iter->idx < i) | |
955b61e5 | 3202 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
3203 | |
3204 | iter->pos = *pos; | |
3205 | ||
bc0c38d1 SR |
3206 | return ent; |
3207 | } | |
3208 | ||
955b61e5 | 3209 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 3210 | { |
2f26ebd5 SR |
3211 | struct ring_buffer_event *event; |
3212 | struct ring_buffer_iter *buf_iter; | |
3213 | unsigned long entries = 0; | |
3214 | u64 ts; | |
3215 | ||
12883efb | 3216 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 3217 | |
6d158a81 SR |
3218 | buf_iter = trace_buffer_iter(iter, cpu); |
3219 | if (!buf_iter) | |
2f26ebd5 SR |
3220 | return; |
3221 | ||
2f26ebd5 SR |
3222 | ring_buffer_iter_reset(buf_iter); |
3223 | ||
3224 | /* | |
3225 | * We could have the case with the max latency tracers | |
3226 | * that a reset never took place on a cpu. This is evident | |
3227 | * by the timestamp being before the start of the buffer. | |
3228 | */ | |
3229 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 3230 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
3231 | break; |
3232 | entries++; | |
3233 | ring_buffer_read(buf_iter, NULL); | |
3234 | } | |
3235 | ||
12883efb | 3236 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
3237 | } |
3238 | ||
d7350c3f | 3239 | /* |
d7350c3f FW |
3240 | * The current tracer is copied to avoid a global locking |
3241 | * all around. | |
3242 | */ | |
bc0c38d1 SR |
3243 | static void *s_start(struct seq_file *m, loff_t *pos) |
3244 | { | |
3245 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 3246 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 3247 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
3248 | void *p = NULL; |
3249 | loff_t l = 0; | |
3928a8a2 | 3250 | int cpu; |
bc0c38d1 | 3251 | |
2fd196ec HT |
3252 | /* |
3253 | * copy the tracer to avoid using a global lock all around. | |
3254 | * iter->trace is a copy of current_trace, the pointer to the | |
3255 | * name may be used instead of a strcmp(), as iter->trace->name | |
3256 | * will point to the same string as current_trace->name. | |
3257 | */ | |
bc0c38d1 | 3258 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3259 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
3260 | *iter->trace = *tr->current_trace; | |
d7350c3f | 3261 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 3262 | |
12883efb | 3263 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
3264 | if (iter->snapshot && iter->trace->use_max_tr) |
3265 | return ERR_PTR(-EBUSY); | |
12883efb | 3266 | #endif |
debdd57f HT |
3267 | |
3268 | if (!iter->snapshot) | |
d914ba37 | 3269 | atomic_inc(&trace_record_taskinfo_disabled); |
bc0c38d1 | 3270 | |
bc0c38d1 SR |
3271 | if (*pos != iter->pos) { |
3272 | iter->ent = NULL; | |
3273 | iter->cpu = 0; | |
3274 | iter->idx = -1; | |
3275 | ||
ae3b5093 | 3276 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3277 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 3278 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 3279 | } else |
2f26ebd5 | 3280 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 3281 | |
ac91d854 | 3282 | iter->leftover = 0; |
bc0c38d1 SR |
3283 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
3284 | ; | |
3285 | ||
3286 | } else { | |
a63ce5b3 SR |
3287 | /* |
3288 | * If we overflowed the seq_file before, then we want | |
3289 | * to just reuse the trace_seq buffer again. | |
3290 | */ | |
3291 | if (iter->leftover) | |
3292 | p = iter; | |
3293 | else { | |
3294 | l = *pos - 1; | |
3295 | p = s_next(m, p, &l); | |
3296 | } | |
bc0c38d1 SR |
3297 | } |
3298 | ||
4f535968 | 3299 | trace_event_read_lock(); |
7e53bd42 | 3300 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
3301 | return p; |
3302 | } | |
3303 | ||
3304 | static void s_stop(struct seq_file *m, void *p) | |
3305 | { | |
7e53bd42 LJ |
3306 | struct trace_iterator *iter = m->private; |
3307 | ||
12883efb | 3308 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
3309 | if (iter->snapshot && iter->trace->use_max_tr) |
3310 | return; | |
12883efb | 3311 | #endif |
debdd57f HT |
3312 | |
3313 | if (!iter->snapshot) | |
d914ba37 | 3314 | atomic_dec(&trace_record_taskinfo_disabled); |
12883efb | 3315 | |
7e53bd42 | 3316 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3317 | trace_event_read_unlock(); |
bc0c38d1 SR |
3318 | } |
3319 | ||
39eaf7ef | 3320 | static void |
12883efb SRRH |
3321 | get_total_entries(struct trace_buffer *buf, |
3322 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
3323 | { |
3324 | unsigned long count; | |
3325 | int cpu; | |
3326 | ||
3327 | *total = 0; | |
3328 | *entries = 0; | |
3329 | ||
3330 | for_each_tracing_cpu(cpu) { | |
12883efb | 3331 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
3332 | /* |
3333 | * If this buffer has skipped entries, then we hold all | |
3334 | * entries for the trace and we need to ignore the | |
3335 | * ones before the time stamp. | |
3336 | */ | |
12883efb SRRH |
3337 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
3338 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
3339 | /* total is the same as the entries */ |
3340 | *total += count; | |
3341 | } else | |
3342 | *total += count + | |
12883efb | 3343 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
3344 | *entries += count; |
3345 | } | |
3346 | } | |
3347 | ||
e309b41d | 3348 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 3349 | { |
d79ac28f RV |
3350 | seq_puts(m, "# _------=> CPU# \n" |
3351 | "# / _-----=> irqs-off \n" | |
3352 | "# | / _----=> need-resched \n" | |
3353 | "# || / _---=> hardirq/softirq \n" | |
3354 | "# ||| / _--=> preempt-depth \n" | |
3355 | "# |||| / delay \n" | |
3356 | "# cmd pid ||||| time | caller \n" | |
3357 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
3358 | } |
3359 | ||
12883efb | 3360 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 3361 | { |
39eaf7ef SR |
3362 | unsigned long total; |
3363 | unsigned long entries; | |
3364 | ||
12883efb | 3365 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
3366 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
3367 | entries, total, num_online_cpus()); | |
3368 | seq_puts(m, "#\n"); | |
3369 | } | |
3370 | ||
441dae8f JF |
3371 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m, |
3372 | unsigned int flags) | |
39eaf7ef | 3373 | { |
441dae8f JF |
3374 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
3375 | ||
12883efb | 3376 | print_event_info(buf, m); |
441dae8f | 3377 | |
36244e3a JFG |
3378 | seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? "TGID " : ""); |
3379 | seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); | |
bc0c38d1 SR |
3380 | } |
3381 | ||
441dae8f JF |
3382 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m, |
3383 | unsigned int flags) | |
77271ce4 | 3384 | { |
441dae8f | 3385 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
b11fb737 SRV |
3386 | const char tgid_space[] = " "; |
3387 | const char space[] = " "; | |
3388 | ||
ee6e4d34 QP |
3389 | print_event_info(buf, m); |
3390 | ||
b11fb737 SRV |
3391 | seq_printf(m, "# %s _-----=> irqs-off\n", |
3392 | tgid ? tgid_space : space); | |
3393 | seq_printf(m, "# %s / _----=> need-resched\n", | |
3394 | tgid ? tgid_space : space); | |
3395 | seq_printf(m, "# %s| / _---=> hardirq/softirq\n", | |
3396 | tgid ? tgid_space : space); | |
3397 | seq_printf(m, "# %s|| / _--=> preempt-depth\n", | |
3398 | tgid ? tgid_space : space); | |
3399 | seq_printf(m, "# %s||| / delay\n", | |
3400 | tgid ? tgid_space : space); | |
36244e3a | 3401 | seq_printf(m, "# TASK-PID %sCPU# |||| TIMESTAMP FUNCTION\n", |
b11fb737 | 3402 | tgid ? " TGID " : space); |
36244e3a | 3403 | seq_printf(m, "# | | %s | |||| | |\n", |
b11fb737 | 3404 | tgid ? " | " : space); |
77271ce4 | 3405 | } |
bc0c38d1 | 3406 | |
62b915f1 | 3407 | void |
bc0c38d1 SR |
3408 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
3409 | { | |
983f938a | 3410 | unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); |
12883efb SRRH |
3411 | struct trace_buffer *buf = iter->trace_buffer; |
3412 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 3413 | struct tracer *type = iter->trace; |
39eaf7ef SR |
3414 | unsigned long entries; |
3415 | unsigned long total; | |
bc0c38d1 SR |
3416 | const char *name = "preemption"; |
3417 | ||
d840f718 | 3418 | name = type->name; |
bc0c38d1 | 3419 | |
12883efb | 3420 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 3421 | |
888b55dc | 3422 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 3423 | name, UTS_RELEASE); |
888b55dc | 3424 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 3425 | "---------------------------------\n"); |
888b55dc | 3426 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 3427 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 3428 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 3429 | entries, |
4c11d7ae | 3430 | total, |
12883efb | 3431 | buf->cpu, |
bc0c38d1 SR |
3432 | #if defined(CONFIG_PREEMPT_NONE) |
3433 | "server", | |
3434 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
3435 | "desktop", | |
b5c21b45 | 3436 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
3437 | "preempt", |
3438 | #else | |
3439 | "unknown", | |
3440 | #endif | |
3441 | /* These are reserved for later use */ | |
3442 | 0, 0, 0, 0); | |
3443 | #ifdef CONFIG_SMP | |
3444 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
3445 | #else | |
3446 | seq_puts(m, ")\n"); | |
3447 | #endif | |
888b55dc KM |
3448 | seq_puts(m, "# -----------------\n"); |
3449 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 3450 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
3451 | data->comm, data->pid, |
3452 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 3453 | data->policy, data->rt_priority); |
888b55dc | 3454 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
3455 | |
3456 | if (data->critical_start) { | |
888b55dc | 3457 | seq_puts(m, "# => started at: "); |
214023c3 SR |
3458 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
3459 | trace_print_seq(m, &iter->seq); | |
888b55dc | 3460 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
3461 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
3462 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 3463 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
3464 | } |
3465 | ||
888b55dc | 3466 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
3467 | } |
3468 | ||
a309720c SR |
3469 | static void test_cpu_buff_start(struct trace_iterator *iter) |
3470 | { | |
3471 | struct trace_seq *s = &iter->seq; | |
983f938a | 3472 | struct trace_array *tr = iter->tr; |
a309720c | 3473 | |
983f938a | 3474 | if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) |
12ef7d44 SR |
3475 | return; |
3476 | ||
3477 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
3478 | return; | |
3479 | ||
4dbbe2d8 MK |
3480 | if (cpumask_available(iter->started) && |
3481 | cpumask_test_cpu(iter->cpu, iter->started)) | |
a309720c SR |
3482 | return; |
3483 | ||
12883efb | 3484 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
3485 | return; |
3486 | ||
4dbbe2d8 | 3487 | if (cpumask_available(iter->started)) |
919cd979 | 3488 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
3489 | |
3490 | /* Don't print started cpu buffer for the first entry of the trace */ | |
3491 | if (iter->idx > 1) | |
3492 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
3493 | iter->cpu); | |
a309720c SR |
3494 | } |
3495 | ||
2c4f035f | 3496 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 3497 | { |
983f938a | 3498 | struct trace_array *tr = iter->tr; |
214023c3 | 3499 | struct trace_seq *s = &iter->seq; |
983f938a | 3500 | unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 3501 | struct trace_entry *entry; |
f633cef0 | 3502 | struct trace_event *event; |
bc0c38d1 | 3503 | |
4e3c3333 | 3504 | entry = iter->ent; |
dd0e545f | 3505 | |
a309720c SR |
3506 | test_cpu_buff_start(iter); |
3507 | ||
c4a8e8be | 3508 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 3509 | |
983f938a | 3510 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
3511 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
3512 | trace_print_lat_context(iter); | |
3513 | else | |
3514 | trace_print_context(iter); | |
c4a8e8be | 3515 | } |
bc0c38d1 | 3516 | |
19a7fe20 SRRH |
3517 | if (trace_seq_has_overflowed(s)) |
3518 | return TRACE_TYPE_PARTIAL_LINE; | |
3519 | ||
268ccda0 | 3520 | if (event) |
a9a57763 | 3521 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 3522 | |
19a7fe20 | 3523 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 3524 | |
19a7fe20 | 3525 | return trace_handle_return(s); |
bc0c38d1 SR |
3526 | } |
3527 | ||
2c4f035f | 3528 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 | 3529 | { |
983f938a | 3530 | struct trace_array *tr = iter->tr; |
f9896bf3 IM |
3531 | struct trace_seq *s = &iter->seq; |
3532 | struct trace_entry *entry; | |
f633cef0 | 3533 | struct trace_event *event; |
f9896bf3 IM |
3534 | |
3535 | entry = iter->ent; | |
dd0e545f | 3536 | |
983f938a | 3537 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) |
19a7fe20 SRRH |
3538 | trace_seq_printf(s, "%d %d %llu ", |
3539 | entry->pid, iter->cpu, iter->ts); | |
3540 | ||
3541 | if (trace_seq_has_overflowed(s)) | |
3542 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 3543 | |
f633cef0 | 3544 | event = ftrace_find_event(entry->type); |
268ccda0 | 3545 | if (event) |
a9a57763 | 3546 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 3547 | |
19a7fe20 | 3548 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 3549 | |
19a7fe20 | 3550 | return trace_handle_return(s); |
f9896bf3 IM |
3551 | } |
3552 | ||
2c4f035f | 3553 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec | 3554 | { |
983f938a | 3555 | struct trace_array *tr = iter->tr; |
5e3ca0ec IM |
3556 | struct trace_seq *s = &iter->seq; |
3557 | unsigned char newline = '\n'; | |
3558 | struct trace_entry *entry; | |
f633cef0 | 3559 | struct trace_event *event; |
5e3ca0ec IM |
3560 | |
3561 | entry = iter->ent; | |
dd0e545f | 3562 | |
983f938a | 3563 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
3564 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
3565 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
3566 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
3567 | if (trace_seq_has_overflowed(s)) | |
3568 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 3569 | } |
5e3ca0ec | 3570 | |
f633cef0 | 3571 | event = ftrace_find_event(entry->type); |
268ccda0 | 3572 | if (event) { |
a9a57763 | 3573 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
3574 | if (ret != TRACE_TYPE_HANDLED) |
3575 | return ret; | |
3576 | } | |
7104f300 | 3577 | |
19a7fe20 | 3578 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 3579 | |
19a7fe20 | 3580 | return trace_handle_return(s); |
5e3ca0ec IM |
3581 | } |
3582 | ||
2c4f035f | 3583 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa | 3584 | { |
983f938a | 3585 | struct trace_array *tr = iter->tr; |
cb0f12aa IM |
3586 | struct trace_seq *s = &iter->seq; |
3587 | struct trace_entry *entry; | |
f633cef0 | 3588 | struct trace_event *event; |
cb0f12aa IM |
3589 | |
3590 | entry = iter->ent; | |
dd0e545f | 3591 | |
983f938a | 3592 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
3593 | SEQ_PUT_FIELD(s, entry->pid); |
3594 | SEQ_PUT_FIELD(s, iter->cpu); | |
3595 | SEQ_PUT_FIELD(s, iter->ts); | |
3596 | if (trace_seq_has_overflowed(s)) | |
3597 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 3598 | } |
cb0f12aa | 3599 | |
f633cef0 | 3600 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
3601 | return event ? event->funcs->binary(iter, 0, event) : |
3602 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
3603 | } |
3604 | ||
62b915f1 | 3605 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 3606 | { |
6d158a81 | 3607 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
3608 | int cpu; |
3609 | ||
9aba60fe | 3610 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 3611 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 3612 | cpu = iter->cpu_file; |
6d158a81 SR |
3613 | buf_iter = trace_buffer_iter(iter, cpu); |
3614 | if (buf_iter) { | |
3615 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
3616 | return 0; |
3617 | } else { | |
12883efb | 3618 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
3619 | return 0; |
3620 | } | |
3621 | return 1; | |
3622 | } | |
3623 | ||
ab46428c | 3624 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
3625 | buf_iter = trace_buffer_iter(iter, cpu); |
3626 | if (buf_iter) { | |
3627 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
3628 | return 0; |
3629 | } else { | |
12883efb | 3630 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
3631 | return 0; |
3632 | } | |
bc0c38d1 | 3633 | } |
d769041f | 3634 | |
797d3712 | 3635 | return 1; |
bc0c38d1 SR |
3636 | } |
3637 | ||
4f535968 | 3638 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 3639 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 3640 | { |
983f938a SRRH |
3641 | struct trace_array *tr = iter->tr; |
3642 | unsigned long trace_flags = tr->trace_flags; | |
2c4f035f FW |
3643 | enum print_line_t ret; |
3644 | ||
19a7fe20 SRRH |
3645 | if (iter->lost_events) { |
3646 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
3647 | iter->cpu, iter->lost_events); | |
3648 | if (trace_seq_has_overflowed(&iter->seq)) | |
3649 | return TRACE_TYPE_PARTIAL_LINE; | |
3650 | } | |
bc21b478 | 3651 | |
2c4f035f FW |
3652 | if (iter->trace && iter->trace->print_line) { |
3653 | ret = iter->trace->print_line(iter); | |
3654 | if (ret != TRACE_TYPE_UNHANDLED) | |
3655 | return ret; | |
3656 | } | |
72829bc3 | 3657 | |
09ae7234 SRRH |
3658 | if (iter->ent->type == TRACE_BPUTS && |
3659 | trace_flags & TRACE_ITER_PRINTK && | |
3660 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
3661 | return trace_print_bputs_msg_only(iter); | |
3662 | ||
48ead020 FW |
3663 | if (iter->ent->type == TRACE_BPRINT && |
3664 | trace_flags & TRACE_ITER_PRINTK && | |
3665 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 3666 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 3667 | |
66896a85 FW |
3668 | if (iter->ent->type == TRACE_PRINT && |
3669 | trace_flags & TRACE_ITER_PRINTK && | |
3670 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 3671 | return trace_print_printk_msg_only(iter); |
66896a85 | 3672 | |
cb0f12aa IM |
3673 | if (trace_flags & TRACE_ITER_BIN) |
3674 | return print_bin_fmt(iter); | |
3675 | ||
5e3ca0ec IM |
3676 | if (trace_flags & TRACE_ITER_HEX) |
3677 | return print_hex_fmt(iter); | |
3678 | ||
f9896bf3 IM |
3679 | if (trace_flags & TRACE_ITER_RAW) |
3680 | return print_raw_fmt(iter); | |
3681 | ||
f9896bf3 IM |
3682 | return print_trace_fmt(iter); |
3683 | } | |
3684 | ||
7e9a49ef JO |
3685 | void trace_latency_header(struct seq_file *m) |
3686 | { | |
3687 | struct trace_iterator *iter = m->private; | |
983f938a | 3688 | struct trace_array *tr = iter->tr; |
7e9a49ef JO |
3689 | |
3690 | /* print nothing if the buffers are empty */ | |
3691 | if (trace_empty(iter)) | |
3692 | return; | |
3693 | ||
3694 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
3695 | print_trace_header(m, iter); | |
3696 | ||
983f938a | 3697 | if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) |
7e9a49ef JO |
3698 | print_lat_help_header(m); |
3699 | } | |
3700 | ||
62b915f1 JO |
3701 | void trace_default_header(struct seq_file *m) |
3702 | { | |
3703 | struct trace_iterator *iter = m->private; | |
983f938a SRRH |
3704 | struct trace_array *tr = iter->tr; |
3705 | unsigned long trace_flags = tr->trace_flags; | |
62b915f1 | 3706 | |
f56e7f8e JO |
3707 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
3708 | return; | |
3709 | ||
62b915f1 JO |
3710 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
3711 | /* print nothing if the buffers are empty */ | |
3712 | if (trace_empty(iter)) | |
3713 | return; | |
3714 | print_trace_header(m, iter); | |
3715 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
3716 | print_lat_help_header(m); | |
3717 | } else { | |
77271ce4 SR |
3718 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
3719 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
441dae8f JF |
3720 | print_func_help_header_irq(iter->trace_buffer, |
3721 | m, trace_flags); | |
77271ce4 | 3722 | else |
441dae8f JF |
3723 | print_func_help_header(iter->trace_buffer, m, |
3724 | trace_flags); | |
77271ce4 | 3725 | } |
62b915f1 JO |
3726 | } |
3727 | } | |
3728 | ||
e0a413f6 SR |
3729 | static void test_ftrace_alive(struct seq_file *m) |
3730 | { | |
3731 | if (!ftrace_is_dead()) | |
3732 | return; | |
d79ac28f RV |
3733 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
3734 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
3735 | } |
3736 | ||
d8741e2e | 3737 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 3738 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 3739 | { |
d79ac28f RV |
3740 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
3741 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
3742 | "# Takes a snapshot of the main buffer.\n" | |
3743 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
3744 | "# (Doesn't have to be '2' works with any number that\n" | |
3745 | "# is not a '0' or '1')\n"); | |
d8741e2e | 3746 | } |
f1affcaa SRRH |
3747 | |
3748 | static void show_snapshot_percpu_help(struct seq_file *m) | |
3749 | { | |
fa6f0cc7 | 3750 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 3751 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
3752 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
3753 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 3754 | #else |
d79ac28f RV |
3755 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
3756 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 3757 | #endif |
d79ac28f RV |
3758 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
3759 | "# (Doesn't have to be '2' works with any number that\n" | |
3760 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
3761 | } |
3762 | ||
d8741e2e SRRH |
3763 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
3764 | { | |
45ad21ca | 3765 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 3766 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 3767 | else |
fa6f0cc7 | 3768 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 3769 | |
fa6f0cc7 | 3770 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
3771 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
3772 | show_snapshot_main_help(m); | |
3773 | else | |
3774 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
3775 | } |
3776 | #else | |
3777 | /* Should never be called */ | |
3778 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
3779 | #endif | |
3780 | ||
bc0c38d1 SR |
3781 | static int s_show(struct seq_file *m, void *v) |
3782 | { | |
3783 | struct trace_iterator *iter = v; | |
a63ce5b3 | 3784 | int ret; |
bc0c38d1 SR |
3785 | |
3786 | if (iter->ent == NULL) { | |
3787 | if (iter->tr) { | |
3788 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
3789 | seq_puts(m, "#\n"); | |
e0a413f6 | 3790 | test_ftrace_alive(m); |
bc0c38d1 | 3791 | } |
d8741e2e SRRH |
3792 | if (iter->snapshot && trace_empty(iter)) |
3793 | print_snapshot_help(m, iter); | |
3794 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 3795 | iter->trace->print_header(m); |
62b915f1 JO |
3796 | else |
3797 | trace_default_header(m); | |
3798 | ||
a63ce5b3 SR |
3799 | } else if (iter->leftover) { |
3800 | /* | |
3801 | * If we filled the seq_file buffer earlier, we | |
3802 | * want to just show it now. | |
3803 | */ | |
3804 | ret = trace_print_seq(m, &iter->seq); | |
3805 | ||
3806 | /* ret should this time be zero, but you never know */ | |
3807 | iter->leftover = ret; | |
3808 | ||
bc0c38d1 | 3809 | } else { |
f9896bf3 | 3810 | print_trace_line(iter); |
a63ce5b3 SR |
3811 | ret = trace_print_seq(m, &iter->seq); |
3812 | /* | |
3813 | * If we overflow the seq_file buffer, then it will | |
3814 | * ask us for this data again at start up. | |
3815 | * Use that instead. | |
3816 | * ret is 0 if seq_file write succeeded. | |
3817 | * -1 otherwise. | |
3818 | */ | |
3819 | iter->leftover = ret; | |
bc0c38d1 SR |
3820 | } |
3821 | ||
3822 | return 0; | |
3823 | } | |
3824 | ||
649e9c70 ON |
3825 | /* |
3826 | * Should be used after trace_array_get(), trace_types_lock | |
3827 | * ensures that i_cdev was already initialized. | |
3828 | */ | |
3829 | static inline int tracing_get_cpu(struct inode *inode) | |
3830 | { | |
3831 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
3832 | return (long)inode->i_cdev - 1; | |
3833 | return RING_BUFFER_ALL_CPUS; | |
3834 | } | |
3835 | ||
88e9d34c | 3836 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
3837 | .start = s_start, |
3838 | .next = s_next, | |
3839 | .stop = s_stop, | |
3840 | .show = s_show, | |
bc0c38d1 SR |
3841 | }; |
3842 | ||
e309b41d | 3843 | static struct trace_iterator * |
6484c71c | 3844 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 3845 | { |
6484c71c | 3846 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 3847 | struct trace_iterator *iter; |
50e18b94 | 3848 | int cpu; |
bc0c38d1 | 3849 | |
85a2f9b4 SR |
3850 | if (tracing_disabled) |
3851 | return ERR_PTR(-ENODEV); | |
60a11774 | 3852 | |
50e18b94 | 3853 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
3854 | if (!iter) |
3855 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 3856 | |
72917235 | 3857 | iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter), |
6d158a81 | 3858 | GFP_KERNEL); |
93574fcc DC |
3859 | if (!iter->buffer_iter) |
3860 | goto release; | |
3861 | ||
d7350c3f FW |
3862 | /* |
3863 | * We make a copy of the current tracer to avoid concurrent | |
3864 | * changes on it while we are reading. | |
3865 | */ | |
bc0c38d1 | 3866 | mutex_lock(&trace_types_lock); |
d7350c3f | 3867 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 3868 | if (!iter->trace) |
d7350c3f | 3869 | goto fail; |
85a2f9b4 | 3870 | |
2b6080f2 | 3871 | *iter->trace = *tr->current_trace; |
d7350c3f | 3872 | |
79f55997 | 3873 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
3874 | goto fail; |
3875 | ||
12883efb SRRH |
3876 | iter->tr = tr; |
3877 | ||
3878 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
3879 | /* Currently only the top directory has a snapshot */ |
3880 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 3881 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 3882 | else |
12883efb SRRH |
3883 | #endif |
3884 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3885 | iter->snapshot = snapshot; |
bc0c38d1 | 3886 | iter->pos = -1; |
6484c71c | 3887 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3888 | mutex_init(&iter->mutex); |
bc0c38d1 | 3889 | |
8bba1bf5 MM |
3890 | /* Notify the tracer early; before we stop tracing. */ |
3891 | if (iter->trace && iter->trace->open) | |
a93751ca | 3892 | iter->trace->open(iter); |
8bba1bf5 | 3893 | |
12ef7d44 | 3894 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3895 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3896 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3897 | ||
8be0709f | 3898 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3899 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3900 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3901 | ||
debdd57f HT |
3902 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3903 | if (!iter->snapshot) | |
2b6080f2 | 3904 | tracing_stop_tr(tr); |
2f26ebd5 | 3905 | |
ae3b5093 | 3906 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3907 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3908 | iter->buffer_iter[cpu] = |
2d412eb3 DA |
3909 | ring_buffer_read_prepare(iter->trace_buffer->buffer, |
3910 | cpu, GFP_KERNEL); | |
72c9ddfd DM |
3911 | } |
3912 | ring_buffer_read_prepare_sync(); | |
3913 | for_each_tracing_cpu(cpu) { | |
3914 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3915 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3916 | } |
3917 | } else { | |
3918 | cpu = iter->cpu_file; | |
3928a8a2 | 3919 | iter->buffer_iter[cpu] = |
2d412eb3 DA |
3920 | ring_buffer_read_prepare(iter->trace_buffer->buffer, |
3921 | cpu, GFP_KERNEL); | |
72c9ddfd DM |
3922 | ring_buffer_read_prepare_sync(); |
3923 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3924 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3925 | } |
3926 | ||
bc0c38d1 SR |
3927 | mutex_unlock(&trace_types_lock); |
3928 | ||
bc0c38d1 | 3929 | return iter; |
3928a8a2 | 3930 | |
d7350c3f | 3931 | fail: |
3928a8a2 | 3932 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3933 | kfree(iter->trace); |
6d158a81 | 3934 | kfree(iter->buffer_iter); |
93574fcc | 3935 | release: |
50e18b94 JO |
3936 | seq_release_private(inode, file); |
3937 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3938 | } |
3939 | ||
3940 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3941 | { | |
60a11774 SR |
3942 | if (tracing_disabled) |
3943 | return -ENODEV; | |
3944 | ||
bc0c38d1 SR |
3945 | filp->private_data = inode->i_private; |
3946 | return 0; | |
3947 | } | |
3948 | ||
2e86421d GB |
3949 | bool tracing_is_disabled(void) |
3950 | { | |
3951 | return (tracing_disabled) ? true: false; | |
3952 | } | |
3953 | ||
7b85af63 SRRH |
3954 | /* |
3955 | * Open and update trace_array ref count. | |
3956 | * Must have the current trace_array passed to it. | |
3957 | */ | |
dcc30223 | 3958 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3959 | { |
3960 | struct trace_array *tr = inode->i_private; | |
3961 | ||
3962 | if (tracing_disabled) | |
3963 | return -ENODEV; | |
3964 | ||
3965 | if (trace_array_get(tr) < 0) | |
3966 | return -ENODEV; | |
3967 | ||
3968 | filp->private_data = inode->i_private; | |
3969 | ||
3970 | return 0; | |
7b85af63 SRRH |
3971 | } |
3972 | ||
4fd27358 | 3973 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3974 | { |
6484c71c | 3975 | struct trace_array *tr = inode->i_private; |
907f2784 | 3976 | struct seq_file *m = file->private_data; |
4acd4d00 | 3977 | struct trace_iterator *iter; |
3928a8a2 | 3978 | int cpu; |
bc0c38d1 | 3979 | |
ff451961 | 3980 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3981 | trace_array_put(tr); |
4acd4d00 | 3982 | return 0; |
ff451961 | 3983 | } |
4acd4d00 | 3984 | |
6484c71c | 3985 | /* Writes do not use seq_file */ |
4acd4d00 | 3986 | iter = m->private; |
bc0c38d1 | 3987 | mutex_lock(&trace_types_lock); |
a695cb58 | 3988 | |
3928a8a2 SR |
3989 | for_each_tracing_cpu(cpu) { |
3990 | if (iter->buffer_iter[cpu]) | |
3991 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3992 | } | |
3993 | ||
bc0c38d1 SR |
3994 | if (iter->trace && iter->trace->close) |
3995 | iter->trace->close(iter); | |
3996 | ||
debdd57f HT |
3997 | if (!iter->snapshot) |
3998 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3999 | tracing_start_tr(tr); |
f77d09a3 AL |
4000 | |
4001 | __trace_array_put(tr); | |
4002 | ||
bc0c38d1 SR |
4003 | mutex_unlock(&trace_types_lock); |
4004 | ||
d7350c3f | 4005 | mutex_destroy(&iter->mutex); |
b0dfa978 | 4006 | free_cpumask_var(iter->started); |
d7350c3f | 4007 | kfree(iter->trace); |
6d158a81 | 4008 | kfree(iter->buffer_iter); |
50e18b94 | 4009 | seq_release_private(inode, file); |
ff451961 | 4010 | |
bc0c38d1 SR |
4011 | return 0; |
4012 | } | |
4013 | ||
7b85af63 SRRH |
4014 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
4015 | { | |
4016 | struct trace_array *tr = inode->i_private; | |
4017 | ||
4018 | trace_array_put(tr); | |
bc0c38d1 SR |
4019 | return 0; |
4020 | } | |
4021 | ||
7b85af63 SRRH |
4022 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
4023 | { | |
4024 | struct trace_array *tr = inode->i_private; | |
4025 | ||
4026 | trace_array_put(tr); | |
4027 | ||
4028 | return single_release(inode, file); | |
4029 | } | |
4030 | ||
bc0c38d1 SR |
4031 | static int tracing_open(struct inode *inode, struct file *file) |
4032 | { | |
6484c71c | 4033 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
4034 | struct trace_iterator *iter; |
4035 | int ret = 0; | |
bc0c38d1 | 4036 | |
ff451961 SRRH |
4037 | if (trace_array_get(tr) < 0) |
4038 | return -ENODEV; | |
4039 | ||
4acd4d00 | 4040 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
4041 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
4042 | int cpu = tracing_get_cpu(inode); | |
8dd33bcb BY |
4043 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4044 | ||
4045 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4046 | if (tr->current_trace->print_max) | |
4047 | trace_buf = &tr->max_buffer; | |
4048 | #endif | |
6484c71c ON |
4049 | |
4050 | if (cpu == RING_BUFFER_ALL_CPUS) | |
8dd33bcb | 4051 | tracing_reset_online_cpus(trace_buf); |
4acd4d00 | 4052 | else |
8dd33bcb | 4053 | tracing_reset(trace_buf, cpu); |
4acd4d00 | 4054 | } |
bc0c38d1 | 4055 | |
4acd4d00 | 4056 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4057 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
4058 | if (IS_ERR(iter)) |
4059 | ret = PTR_ERR(iter); | |
983f938a | 4060 | else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
4acd4d00 SR |
4061 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
4062 | } | |
ff451961 SRRH |
4063 | |
4064 | if (ret < 0) | |
4065 | trace_array_put(tr); | |
4066 | ||
bc0c38d1 SR |
4067 | return ret; |
4068 | } | |
4069 | ||
607e2ea1 SRRH |
4070 | /* |
4071 | * Some tracers are not suitable for instance buffers. | |
4072 | * A tracer is always available for the global array (toplevel) | |
4073 | * or if it explicitly states that it is. | |
4074 | */ | |
4075 | static bool | |
4076 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
4077 | { | |
4078 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
4079 | } | |
4080 | ||
4081 | /* Find the next tracer that this trace array may use */ | |
4082 | static struct tracer * | |
4083 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
4084 | { | |
4085 | while (t && !trace_ok_for_array(t, tr)) | |
4086 | t = t->next; | |
4087 | ||
4088 | return t; | |
4089 | } | |
4090 | ||
e309b41d | 4091 | static void * |
bc0c38d1 SR |
4092 | t_next(struct seq_file *m, void *v, loff_t *pos) |
4093 | { | |
607e2ea1 | 4094 | struct trace_array *tr = m->private; |
f129e965 | 4095 | struct tracer *t = v; |
bc0c38d1 SR |
4096 | |
4097 | (*pos)++; | |
4098 | ||
4099 | if (t) | |
607e2ea1 | 4100 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 4101 | |
bc0c38d1 SR |
4102 | return t; |
4103 | } | |
4104 | ||
4105 | static void *t_start(struct seq_file *m, loff_t *pos) | |
4106 | { | |
607e2ea1 | 4107 | struct trace_array *tr = m->private; |
f129e965 | 4108 | struct tracer *t; |
bc0c38d1 SR |
4109 | loff_t l = 0; |
4110 | ||
4111 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
4112 | |
4113 | t = get_tracer_for_array(tr, trace_types); | |
4114 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
4115 | ; | |
bc0c38d1 SR |
4116 | |
4117 | return t; | |
4118 | } | |
4119 | ||
4120 | static void t_stop(struct seq_file *m, void *p) | |
4121 | { | |
4122 | mutex_unlock(&trace_types_lock); | |
4123 | } | |
4124 | ||
4125 | static int t_show(struct seq_file *m, void *v) | |
4126 | { | |
4127 | struct tracer *t = v; | |
4128 | ||
4129 | if (!t) | |
4130 | return 0; | |
4131 | ||
fa6f0cc7 | 4132 | seq_puts(m, t->name); |
bc0c38d1 SR |
4133 | if (t->next) |
4134 | seq_putc(m, ' '); | |
4135 | else | |
4136 | seq_putc(m, '\n'); | |
4137 | ||
4138 | return 0; | |
4139 | } | |
4140 | ||
88e9d34c | 4141 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
4142 | .start = t_start, |
4143 | .next = t_next, | |
4144 | .stop = t_stop, | |
4145 | .show = t_show, | |
bc0c38d1 SR |
4146 | }; |
4147 | ||
4148 | static int show_traces_open(struct inode *inode, struct file *file) | |
4149 | { | |
607e2ea1 SRRH |
4150 | struct trace_array *tr = inode->i_private; |
4151 | struct seq_file *m; | |
4152 | int ret; | |
4153 | ||
60a11774 SR |
4154 | if (tracing_disabled) |
4155 | return -ENODEV; | |
4156 | ||
faf6784d SRV |
4157 | if (trace_array_get(tr) < 0) |
4158 | return -ENODEV; | |
4159 | ||
607e2ea1 | 4160 | ret = seq_open(file, &show_traces_seq_ops); |
faf6784d SRV |
4161 | if (ret) { |
4162 | trace_array_put(tr); | |
607e2ea1 | 4163 | return ret; |
faf6784d | 4164 | } |
607e2ea1 SRRH |
4165 | |
4166 | m = file->private_data; | |
4167 | m->private = tr; | |
4168 | ||
4169 | return 0; | |
bc0c38d1 SR |
4170 | } |
4171 | ||
faf6784d SRV |
4172 | static int show_traces_release(struct inode *inode, struct file *file) |
4173 | { | |
4174 | struct trace_array *tr = inode->i_private; | |
4175 | ||
4176 | trace_array_put(tr); | |
4177 | return seq_release(inode, file); | |
4178 | } | |
4179 | ||
4acd4d00 SR |
4180 | static ssize_t |
4181 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
4182 | size_t count, loff_t *ppos) | |
4183 | { | |
4184 | return count; | |
4185 | } | |
4186 | ||
098c879e | 4187 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 4188 | { |
098c879e SRRH |
4189 | int ret; |
4190 | ||
364829b1 | 4191 | if (file->f_mode & FMODE_READ) |
098c879e | 4192 | ret = seq_lseek(file, offset, whence); |
364829b1 | 4193 | else |
098c879e SRRH |
4194 | file->f_pos = ret = 0; |
4195 | ||
4196 | return ret; | |
364829b1 SP |
4197 | } |
4198 | ||
5e2336a0 | 4199 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
4200 | .open = tracing_open, |
4201 | .read = seq_read, | |
4acd4d00 | 4202 | .write = tracing_write_stub, |
098c879e | 4203 | .llseek = tracing_lseek, |
4bf39a94 | 4204 | .release = tracing_release, |
bc0c38d1 SR |
4205 | }; |
4206 | ||
5e2336a0 | 4207 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
4208 | .open = show_traces_open, |
4209 | .read = seq_read, | |
b444786f | 4210 | .llseek = seq_lseek, |
faf6784d | 4211 | .release = show_traces_release, |
c7078de1 IM |
4212 | }; |
4213 | ||
4214 | static ssize_t | |
4215 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
4216 | size_t count, loff_t *ppos) | |
4217 | { | |
ccfe9e42 | 4218 | struct trace_array *tr = file_inode(filp)->i_private; |
b8582c0f | 4219 | char *mask_str; |
36dfe925 | 4220 | int len; |
c7078de1 | 4221 | |
b8582c0f CD |
4222 | len = snprintf(NULL, 0, "%*pb\n", |
4223 | cpumask_pr_args(tr->tracing_cpumask)) + 1; | |
4224 | mask_str = kmalloc(len, GFP_KERNEL); | |
4225 | if (!mask_str) | |
4226 | return -ENOMEM; | |
36dfe925 | 4227 | |
b8582c0f | 4228 | len = snprintf(mask_str, len, "%*pb\n", |
1a40243b TH |
4229 | cpumask_pr_args(tr->tracing_cpumask)); |
4230 | if (len >= count) { | |
36dfe925 IM |
4231 | count = -EINVAL; |
4232 | goto out_err; | |
4233 | } | |
b8582c0f | 4234 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, len); |
36dfe925 IM |
4235 | |
4236 | out_err: | |
b8582c0f | 4237 | kfree(mask_str); |
c7078de1 IM |
4238 | |
4239 | return count; | |
4240 | } | |
4241 | ||
4242 | static ssize_t | |
4243 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
4244 | size_t count, loff_t *ppos) | |
4245 | { | |
ccfe9e42 | 4246 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 4247 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 4248 | int err, cpu; |
9e01c1b7 RR |
4249 | |
4250 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
4251 | return -ENOMEM; | |
c7078de1 | 4252 | |
9e01c1b7 | 4253 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 4254 | if (err) |
36dfe925 IM |
4255 | goto err_unlock; |
4256 | ||
a5e25883 | 4257 | local_irq_disable(); |
0b9b12c1 | 4258 | arch_spin_lock(&tr->max_lock); |
ab46428c | 4259 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
4260 | /* |
4261 | * Increase/decrease the disabled counter if we are | |
4262 | * about to flip a bit in the cpumask: | |
4263 | */ | |
ccfe9e42 | 4264 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 4265 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
4266 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
4267 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 4268 | } |
ccfe9e42 | 4269 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 4270 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
4271 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
4272 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
4273 | } |
4274 | } | |
0b9b12c1 | 4275 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 4276 | local_irq_enable(); |
36dfe925 | 4277 | |
ccfe9e42 | 4278 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
9e01c1b7 | 4279 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
4280 | |
4281 | return count; | |
36dfe925 IM |
4282 | |
4283 | err_unlock: | |
215368e8 | 4284 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
4285 | |
4286 | return err; | |
c7078de1 IM |
4287 | } |
4288 | ||
5e2336a0 | 4289 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 4290 | .open = tracing_open_generic_tr, |
c7078de1 IM |
4291 | .read = tracing_cpumask_read, |
4292 | .write = tracing_cpumask_write, | |
ccfe9e42 | 4293 | .release = tracing_release_generic_tr, |
b444786f | 4294 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4295 | }; |
4296 | ||
fdb372ed | 4297 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 4298 | { |
d8e83d26 | 4299 | struct tracer_opt *trace_opts; |
2b6080f2 | 4300 | struct trace_array *tr = m->private; |
d8e83d26 | 4301 | u32 tracer_flags; |
d8e83d26 | 4302 | int i; |
adf9f195 | 4303 | |
d8e83d26 | 4304 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4305 | tracer_flags = tr->current_trace->flags->val; |
4306 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 4307 | |
bc0c38d1 | 4308 | for (i = 0; trace_options[i]; i++) { |
983f938a | 4309 | if (tr->trace_flags & (1 << i)) |
fdb372ed | 4310 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 4311 | else |
fdb372ed | 4312 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
4313 | } |
4314 | ||
adf9f195 FW |
4315 | for (i = 0; trace_opts[i].name; i++) { |
4316 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 4317 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 4318 | else |
fdb372ed | 4319 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 4320 | } |
d8e83d26 | 4321 | mutex_unlock(&trace_types_lock); |
adf9f195 | 4322 | |
fdb372ed | 4323 | return 0; |
bc0c38d1 | 4324 | } |
bc0c38d1 | 4325 | |
8c1a49ae | 4326 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
4327 | struct tracer_flags *tracer_flags, |
4328 | struct tracer_opt *opts, int neg) | |
4329 | { | |
d39cdd20 | 4330 | struct tracer *trace = tracer_flags->trace; |
8d18eaaf | 4331 | int ret; |
bc0c38d1 | 4332 | |
8c1a49ae | 4333 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
4334 | if (ret) |
4335 | return ret; | |
4336 | ||
4337 | if (neg) | |
4338 | tracer_flags->val &= ~opts->bit; | |
4339 | else | |
4340 | tracer_flags->val |= opts->bit; | |
4341 | return 0; | |
bc0c38d1 SR |
4342 | } |
4343 | ||
adf9f195 | 4344 | /* Try to assign a tracer specific option */ |
8c1a49ae | 4345 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 4346 | { |
8c1a49ae | 4347 | struct tracer *trace = tr->current_trace; |
7770841e | 4348 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 4349 | struct tracer_opt *opts = NULL; |
8d18eaaf | 4350 | int i; |
adf9f195 | 4351 | |
7770841e Z |
4352 | for (i = 0; tracer_flags->opts[i].name; i++) { |
4353 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 4354 | |
8d18eaaf | 4355 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 4356 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 4357 | } |
adf9f195 | 4358 | |
8d18eaaf | 4359 | return -EINVAL; |
adf9f195 FW |
4360 | } |
4361 | ||
613f04a0 SRRH |
4362 | /* Some tracers require overwrite to stay enabled */ |
4363 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
4364 | { | |
4365 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
4366 | return -1; | |
4367 | ||
4368 | return 0; | |
4369 | } | |
4370 | ||
2b6080f2 | 4371 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd | 4372 | { |
af247192 PS |
4373 | if ((mask == TRACE_ITER_RECORD_TGID) || |
4374 | (mask == TRACE_ITER_RECORD_CMD)) | |
4375 | lockdep_assert_held(&event_mutex); | |
4376 | ||
af4617bd | 4377 | /* do nothing if flag is already set */ |
983f938a | 4378 | if (!!(tr->trace_flags & mask) == !!enabled) |
613f04a0 SRRH |
4379 | return 0; |
4380 | ||
4381 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 4382 | if (tr->current_trace->flag_changed) |
bf6065b5 | 4383 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 4384 | return -EINVAL; |
af4617bd SR |
4385 | |
4386 | if (enabled) | |
983f938a | 4387 | tr->trace_flags |= mask; |
af4617bd | 4388 | else |
983f938a | 4389 | tr->trace_flags &= ~mask; |
e870e9a1 LZ |
4390 | |
4391 | if (mask == TRACE_ITER_RECORD_CMD) | |
4392 | trace_event_enable_cmd_record(enabled); | |
750912fa | 4393 | |
d914ba37 JF |
4394 | if (mask == TRACE_ITER_RECORD_TGID) { |
4395 | if (!tgid_map) | |
4396 | tgid_map = kzalloc((PID_MAX_DEFAULT + 1) * sizeof(*tgid_map), | |
4397 | GFP_KERNEL); | |
4398 | if (!tgid_map) { | |
4399 | tr->trace_flags &= ~TRACE_ITER_RECORD_TGID; | |
4400 | return -ENOMEM; | |
4401 | } | |
4402 | ||
4403 | trace_event_enable_tgid_record(enabled); | |
4404 | } | |
4405 | ||
c37775d5 SR |
4406 | if (mask == TRACE_ITER_EVENT_FORK) |
4407 | trace_event_follow_fork(tr, enabled); | |
4408 | ||
1e10486f NK |
4409 | if (mask == TRACE_ITER_FUNC_FORK) |
4410 | ftrace_pid_follow_fork(tr, enabled); | |
4411 | ||
80902822 | 4412 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 4413 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 4414 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 4415 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
4416 | #endif |
4417 | } | |
81698831 | 4418 | |
b9f9108c | 4419 | if (mask == TRACE_ITER_PRINTK) { |
81698831 | 4420 | trace_printk_start_stop_comm(enabled); |
b9f9108c SRRH |
4421 | trace_printk_control(enabled); |
4422 | } | |
613f04a0 SRRH |
4423 | |
4424 | return 0; | |
af4617bd SR |
4425 | } |
4426 | ||
2b6080f2 | 4427 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 4428 | { |
8d18eaaf | 4429 | char *cmp; |
bc0c38d1 | 4430 | int neg = 0; |
613f04a0 | 4431 | int ret = -ENODEV; |
bc0c38d1 | 4432 | int i; |
a4d1e688 | 4433 | size_t orig_len = strlen(option); |
bc0c38d1 | 4434 | |
7bcfaf54 | 4435 | cmp = strstrip(option); |
bc0c38d1 | 4436 | |
8d18eaaf | 4437 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
4438 | neg = 1; |
4439 | cmp += 2; | |
4440 | } | |
4441 | ||
af247192 | 4442 | mutex_lock(&event_mutex); |
69d34da2 SRRH |
4443 | mutex_lock(&trace_types_lock); |
4444 | ||
bc0c38d1 | 4445 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 4446 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 4447 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
4448 | break; |
4449 | } | |
4450 | } | |
adf9f195 FW |
4451 | |
4452 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 4453 | if (!trace_options[i]) |
8c1a49ae | 4454 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
4455 | |
4456 | mutex_unlock(&trace_types_lock); | |
af247192 | 4457 | mutex_unlock(&event_mutex); |
bc0c38d1 | 4458 | |
a4d1e688 JW |
4459 | /* |
4460 | * If the first trailing whitespace is replaced with '\0' by strstrip, | |
4461 | * turn it back into a space. | |
4462 | */ | |
4463 | if (orig_len > strlen(option)) | |
4464 | option[strlen(option)] = ' '; | |
4465 | ||
7bcfaf54 SR |
4466 | return ret; |
4467 | } | |
4468 | ||
a4d1e688 JW |
4469 | static void __init apply_trace_boot_options(void) |
4470 | { | |
4471 | char *buf = trace_boot_options_buf; | |
4472 | char *option; | |
4473 | ||
4474 | while (true) { | |
4475 | option = strsep(&buf, ","); | |
4476 | ||
4477 | if (!option) | |
4478 | break; | |
a4d1e688 | 4479 | |
43ed3843 SRRH |
4480 | if (*option) |
4481 | trace_set_options(&global_trace, option); | |
a4d1e688 JW |
4482 | |
4483 | /* Put back the comma to allow this to be called again */ | |
4484 | if (buf) | |
4485 | *(buf - 1) = ','; | |
4486 | } | |
4487 | } | |
4488 | ||
7bcfaf54 SR |
4489 | static ssize_t |
4490 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
4491 | size_t cnt, loff_t *ppos) | |
4492 | { | |
2b6080f2 SR |
4493 | struct seq_file *m = filp->private_data; |
4494 | struct trace_array *tr = m->private; | |
7bcfaf54 | 4495 | char buf[64]; |
613f04a0 | 4496 | int ret; |
7bcfaf54 SR |
4497 | |
4498 | if (cnt >= sizeof(buf)) | |
4499 | return -EINVAL; | |
4500 | ||
4afe6495 | 4501 | if (copy_from_user(buf, ubuf, cnt)) |
7bcfaf54 SR |
4502 | return -EFAULT; |
4503 | ||
a8dd2176 SR |
4504 | buf[cnt] = 0; |
4505 | ||
2b6080f2 | 4506 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
4507 | if (ret < 0) |
4508 | return ret; | |
7bcfaf54 | 4509 | |
cf8517cf | 4510 | *ppos += cnt; |
bc0c38d1 SR |
4511 | |
4512 | return cnt; | |
4513 | } | |
4514 | ||
fdb372ed LZ |
4515 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
4516 | { | |
7b85af63 | 4517 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 4518 | int ret; |
7b85af63 | 4519 | |
fdb372ed LZ |
4520 | if (tracing_disabled) |
4521 | return -ENODEV; | |
2b6080f2 | 4522 | |
7b85af63 SRRH |
4523 | if (trace_array_get(tr) < 0) |
4524 | return -ENODEV; | |
4525 | ||
f77d09a3 AL |
4526 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
4527 | if (ret < 0) | |
4528 | trace_array_put(tr); | |
4529 | ||
4530 | return ret; | |
fdb372ed LZ |
4531 | } |
4532 | ||
5e2336a0 | 4533 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
4534 | .open = tracing_trace_options_open, |
4535 | .read = seq_read, | |
4536 | .llseek = seq_lseek, | |
7b85af63 | 4537 | .release = tracing_single_release_tr, |
ee6bce52 | 4538 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
4539 | }; |
4540 | ||
7bd2f24c IM |
4541 | static const char readme_msg[] = |
4542 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
4543 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
4544 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
4545 | " Important files:\n" | |
4546 | " trace\t\t\t- The static contents of the buffer\n" | |
4547 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
4548 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
4549 | " current_tracer\t- function and latency tracers\n" | |
4550 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
4551 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
4552 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
4553 | " trace_clock\t\t-change the clock used to order events\n" | |
4554 | " local: Per cpu clock but may not be synced across CPUs\n" | |
4555 | " global: Synced across CPUs but slows tracing down.\n" | |
4556 | " counter: Not a clock, but just an increment\n" | |
4557 | " uptime: Jiffy counter from time of boot\n" | |
4558 | " perf: Same clock that perf events use\n" | |
4559 | #ifdef CONFIG_X86_64 | |
4560 | " x86-tsc: TSC cycle counter\n" | |
4561 | #endif | |
4562 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
fa32e855 | 4563 | "\n trace_marker_raw\t\t- Writes into this file writes binary data into the kernel buffer\n" |
22f45649 SRRH |
4564 | " tracing_cpumask\t- Limit which CPUs to trace\n" |
4565 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
4566 | "\t\t\t Remove sub-buffer with rmdir\n" | |
4567 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
4568 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
4569 | "\t\t\t option name\n" | |
939c7a4f | 4570 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
4571 | #ifdef CONFIG_DYNAMIC_FTRACE |
4572 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
4573 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
4574 | "\t\t\t functions\n" | |
60f1d5e3 | 4575 | "\t accepts: func_full_name or glob-matching-pattern\n" |
71485c45 SRRH |
4576 | "\t modules: Can select a group via module\n" |
4577 | "\t Format: :mod:<module-name>\n" | |
4578 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
4579 | "\t triggers: a command to perform when function is hit\n" | |
4580 | "\t Format: <function>:<trigger>[:count]\n" | |
4581 | "\t trigger: traceon, traceoff\n" | |
4582 | "\t\t enable_event:<system>:<event>\n" | |
4583 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 4584 | #ifdef CONFIG_STACKTRACE |
71485c45 | 4585 | "\t\t stacktrace\n" |
22f45649 SRRH |
4586 | #endif |
4587 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 4588 | "\t\t snapshot\n" |
22f45649 | 4589 | #endif |
17a280ea SRRH |
4590 | "\t\t dump\n" |
4591 | "\t\t cpudump\n" | |
71485c45 SRRH |
4592 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
4593 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
4594 | "\t The first one will disable tracing every time do_fault is hit\n" | |
4595 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
4596 | "\t The first time do trap is hit and it disables tracing, the\n" | |
4597 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
4598 | "\t the counter will not decrement. It only decrements when the\n" | |
4599 | "\t trigger did work\n" | |
4600 | "\t To remove trigger without count:\n" | |
4601 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
4602 | "\t To remove trigger with a count:\n" | |
4603 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 4604 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
4605 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
4606 | "\t modules: Can select a group via module command :mod:\n" | |
4607 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
4608 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
4609 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
4610 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
4611 | "\t\t (function)\n" | |
22f45649 SRRH |
4612 | #endif |
4613 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
4614 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 4615 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
4616 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
4617 | #endif | |
4618 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
4619 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
4620 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
4621 | "\t\t\t information\n" | |
22f45649 | 4622 | #endif |
991821c8 | 4623 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
4624 | " stack_trace\t\t- Shows the max stack trace when active\n" |
4625 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
4626 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
4627 | "\t\t\t new trace)\n" | |
22f45649 | 4628 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
4629 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
4630 | "\t\t\t traces\n" | |
22f45649 | 4631 | #endif |
991821c8 | 4632 | #endif /* CONFIG_STACK_TRACER */ |
6b0b7551 | 4633 | #ifdef CONFIG_KPROBE_EVENTS |
86425625 MH |
4634 | " kprobe_events\t\t- Add/remove/show the kernel dynamic events\n" |
4635 | "\t\t\t Write into this file to define/undefine new trace events.\n" | |
4636 | #endif | |
6b0b7551 | 4637 | #ifdef CONFIG_UPROBE_EVENTS |
86425625 MH |
4638 | " uprobe_events\t\t- Add/remove/show the userspace dynamic events\n" |
4639 | "\t\t\t Write into this file to define/undefine new trace events.\n" | |
4640 | #endif | |
6b0b7551 | 4641 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
86425625 | 4642 | "\t accepts: event-definitions (one definition per line)\n" |
c3ca46ef MH |
4643 | "\t Format: p[:[<group>/]<event>] <place> [<args>]\n" |
4644 | "\t r[maxactive][:[<group>/]<event>] <place> [<args>]\n" | |
86425625 | 4645 | "\t -:[<group>/]<event>\n" |
6b0b7551 | 4646 | #ifdef CONFIG_KPROBE_EVENTS |
86425625 | 4647 | "\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n" |
35b6f55a | 4648 | "place (kretprobe): [<module>:]<symbol>[+<offset>]|<memaddr>\n" |
86425625 | 4649 | #endif |
6b0b7551 | 4650 | #ifdef CONFIG_UPROBE_EVENTS |
86425625 MH |
4651 | "\t place: <path>:<offset>\n" |
4652 | #endif | |
4653 | "\t args: <name>=fetcharg[:type]\n" | |
4654 | "\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n" | |
4655 | "\t $stack<index>, $stack, $retval, $comm\n" | |
4656 | "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string,\n" | |
4657 | "\t b<bit-width>@<bit-offset>/<container-size>\n" | |
4658 | #endif | |
26f25564 TZ |
4659 | " events/\t\t- Directory containing all trace event subsystems:\n" |
4660 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
4661 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
4662 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
4663 | "\t\t\t events\n" | |
26f25564 | 4664 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
4665 | " events/<system>/<event>/\t- Directory containing control files for\n" |
4666 | "\t\t\t <event>:\n" | |
26f25564 TZ |
4667 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
4668 | " filter\t\t- If set, only events passing filter are traced\n" | |
4669 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
4670 | "\t Format: <trigger>[:count][if <filter>]\n" |
4671 | "\t trigger: traceon, traceoff\n" | |
4672 | "\t enable_event:<system>:<event>\n" | |
4673 | "\t disable_event:<system>:<event>\n" | |
d0bad49b TZ |
4674 | #ifdef CONFIG_HIST_TRIGGERS |
4675 | "\t enable_hist:<system>:<event>\n" | |
4676 | "\t disable_hist:<system>:<event>\n" | |
4677 | #endif | |
26f25564 | 4678 | #ifdef CONFIG_STACKTRACE |
71485c45 | 4679 | "\t\t stacktrace\n" |
26f25564 TZ |
4680 | #endif |
4681 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 4682 | "\t\t snapshot\n" |
7ef224d1 TZ |
4683 | #endif |
4684 | #ifdef CONFIG_HIST_TRIGGERS | |
4685 | "\t\t hist (see below)\n" | |
26f25564 | 4686 | #endif |
71485c45 SRRH |
4687 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
4688 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
4689 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
4690 | "\t events/block/block_unplug/trigger\n" | |
4691 | "\t The first disables tracing every time block_unplug is hit.\n" | |
4692 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
4693 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
4694 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
4695 | "\t Like function triggers, the counter is only decremented if it\n" | |
4696 | "\t enabled or disabled tracing.\n" | |
4697 | "\t To remove a trigger without a count:\n" | |
4698 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
4699 | "\t To remove a trigger with a count:\n" | |
4700 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
4701 | "\t Filters can be ignored when removing a trigger.\n" | |
7ef224d1 TZ |
4702 | #ifdef CONFIG_HIST_TRIGGERS |
4703 | " hist trigger\t- If set, event hits are aggregated into a hash table\n" | |
76a3b0c8 | 4704 | "\t Format: hist:keys=<field1[,field2,...]>\n" |
f2606835 | 4705 | "\t [:values=<field1[,field2,...]>]\n" |
e62347d2 | 4706 | "\t [:sort=<field1[,field2,...]>]\n" |
7ef224d1 | 4707 | "\t [:size=#entries]\n" |
e86ae9ba | 4708 | "\t [:pause][:continue][:clear]\n" |
5463bfda | 4709 | "\t [:name=histname1]\n" |
7ef224d1 TZ |
4710 | "\t [if <filter>]\n\n" |
4711 | "\t When a matching event is hit, an entry is added to a hash\n" | |
f2606835 TZ |
4712 | "\t table using the key(s) and value(s) named, and the value of a\n" |
4713 | "\t sum called 'hitcount' is incremented. Keys and values\n" | |
4714 | "\t correspond to fields in the event's format description. Keys\n" | |
69a0200c TZ |
4715 | "\t can be any field, or the special string 'stacktrace'.\n" |
4716 | "\t Compound keys consisting of up to two fields can be specified\n" | |
4717 | "\t by the 'keys' keyword. Values must correspond to numeric\n" | |
4718 | "\t fields. Sort keys consisting of up to two fields can be\n" | |
4719 | "\t specified using the 'sort' keyword. The sort direction can\n" | |
4720 | "\t be modified by appending '.descending' or '.ascending' to a\n" | |
4721 | "\t sort field. The 'size' parameter can be used to specify more\n" | |
5463bfda TZ |
4722 | "\t or fewer than the default 2048 entries for the hashtable size.\n" |
4723 | "\t If a hist trigger is given a name using the 'name' parameter,\n" | |
4724 | "\t its histogram data will be shared with other triggers of the\n" | |
4725 | "\t same name, and trigger hits will update this common data.\n\n" | |
7ef224d1 | 4726 | "\t Reading the 'hist' file for the event will dump the hash\n" |
52a7f16d TZ |
4727 | "\t table in its entirety to stdout. If there are multiple hist\n" |
4728 | "\t triggers attached to an event, there will be a table for each\n" | |
5463bfda TZ |
4729 | "\t trigger in the output. The table displayed for a named\n" |
4730 | "\t trigger will be the same as any other instance having the\n" | |
4731 | "\t same name. The default format used to display a given field\n" | |
4732 | "\t can be modified by appending any of the following modifiers\n" | |
4733 | "\t to the field name, as applicable:\n\n" | |
c6afad49 TZ |
4734 | "\t .hex display a number as a hex value\n" |
4735 | "\t .sym display an address as a symbol\n" | |
6b4827ad | 4736 | "\t .sym-offset display an address as a symbol and offset\n" |
31696198 TZ |
4737 | "\t .execname display a common_pid as a program name\n" |
4738 | "\t .syscall display a syscall id as a syscall name\n\n" | |
4b94f5b7 | 4739 | "\t .log2 display log2 value rather than raw number\n\n" |
83e99914 TZ |
4740 | "\t The 'pause' parameter can be used to pause an existing hist\n" |
4741 | "\t trigger or to start a hist trigger but not log any events\n" | |
4742 | "\t until told to do so. 'continue' can be used to start or\n" | |
4743 | "\t restart a paused hist trigger.\n\n" | |
e86ae9ba TZ |
4744 | "\t The 'clear' parameter will clear the contents of a running\n" |
4745 | "\t hist trigger and leave its current paused/active state\n" | |
4746 | "\t unchanged.\n\n" | |
d0bad49b TZ |
4747 | "\t The enable_hist and disable_hist triggers can be used to\n" |
4748 | "\t have one event conditionally start and stop another event's\n" | |
4749 | "\t already-attached hist trigger. The syntax is analagous to\n" | |
4750 | "\t the enable_event and disable_event triggers.\n" | |
7ef224d1 | 4751 | #endif |
7bd2f24c IM |
4752 | ; |
4753 | ||
4754 | static ssize_t | |
4755 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
4756 | size_t cnt, loff_t *ppos) | |
4757 | { | |
4758 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
4759 | readme_msg, strlen(readme_msg)); | |
4760 | } | |
4761 | ||
5e2336a0 | 4762 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
4763 | .open = tracing_open_generic, |
4764 | .read = tracing_readme_read, | |
b444786f | 4765 | .llseek = generic_file_llseek, |
7bd2f24c IM |
4766 | }; |
4767 | ||
99c621d7 MS |
4768 | static void *saved_tgids_next(struct seq_file *m, void *v, loff_t *pos) |
4769 | { | |
4770 | int *ptr = v; | |
4771 | ||
4772 | if (*pos || m->count) | |
4773 | ptr++; | |
4774 | ||
4775 | (*pos)++; | |
4776 | ||
4777 | for (; ptr <= &tgid_map[PID_MAX_DEFAULT]; ptr++) { | |
4778 | if (trace_find_tgid(*ptr)) | |
4779 | return ptr; | |
4780 | } | |
4781 | ||
4782 | return NULL; | |
4783 | } | |
4784 | ||
4785 | static void *saved_tgids_start(struct seq_file *m, loff_t *pos) | |
4786 | { | |
4787 | void *v; | |
4788 | loff_t l = 0; | |
4789 | ||
4790 | if (!tgid_map) | |
4791 | return NULL; | |
4792 | ||
4793 | v = &tgid_map[0]; | |
4794 | while (l <= *pos) { | |
4795 | v = saved_tgids_next(m, v, &l); | |
4796 | if (!v) | |
4797 | return NULL; | |
4798 | } | |
4799 | ||
4800 | return v; | |
4801 | } | |
4802 | ||
4803 | static void saved_tgids_stop(struct seq_file *m, void *v) | |
4804 | { | |
4805 | } | |
4806 | ||
4807 | static int saved_tgids_show(struct seq_file *m, void *v) | |
4808 | { | |
4809 | int pid = (int *)v - tgid_map; | |
4810 | ||
4811 | seq_printf(m, "%d %d\n", pid, trace_find_tgid(pid)); | |
4812 | return 0; | |
4813 | } | |
4814 | ||
4815 | static const struct seq_operations tracing_saved_tgids_seq_ops = { | |
4816 | .start = saved_tgids_start, | |
4817 | .stop = saved_tgids_stop, | |
4818 | .next = saved_tgids_next, | |
4819 | .show = saved_tgids_show, | |
4820 | }; | |
4821 | ||
4822 | static int tracing_saved_tgids_open(struct inode *inode, struct file *filp) | |
4823 | { | |
4824 | if (tracing_disabled) | |
4825 | return -ENODEV; | |
4826 | ||
4827 | return seq_open(filp, &tracing_saved_tgids_seq_ops); | |
4828 | } | |
4829 | ||
4830 | ||
4831 | static const struct file_operations tracing_saved_tgids_fops = { | |
4832 | .open = tracing_saved_tgids_open, | |
4833 | .read = seq_read, | |
4834 | .llseek = seq_lseek, | |
4835 | .release = seq_release, | |
4836 | }; | |
4837 | ||
42584c81 YY |
4838 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
4839 | { | |
4840 | unsigned int *ptr = v; | |
69abe6a5 | 4841 | |
42584c81 YY |
4842 | if (*pos || m->count) |
4843 | ptr++; | |
69abe6a5 | 4844 | |
42584c81 | 4845 | (*pos)++; |
69abe6a5 | 4846 | |
939c7a4f YY |
4847 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
4848 | ptr++) { | |
42584c81 YY |
4849 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
4850 | continue; | |
69abe6a5 | 4851 | |
42584c81 YY |
4852 | return ptr; |
4853 | } | |
69abe6a5 | 4854 | |
42584c81 YY |
4855 | return NULL; |
4856 | } | |
4857 | ||
4858 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
4859 | { | |
4860 | void *v; | |
4861 | loff_t l = 0; | |
69abe6a5 | 4862 | |
4c27e756 SRRH |
4863 | preempt_disable(); |
4864 | arch_spin_lock(&trace_cmdline_lock); | |
4865 | ||
939c7a4f | 4866 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
4867 | while (l <= *pos) { |
4868 | v = saved_cmdlines_next(m, v, &l); | |
4869 | if (!v) | |
4870 | return NULL; | |
69abe6a5 AP |
4871 | } |
4872 | ||
42584c81 YY |
4873 | return v; |
4874 | } | |
4875 | ||
4876 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
4877 | { | |
4c27e756 SRRH |
4878 | arch_spin_unlock(&trace_cmdline_lock); |
4879 | preempt_enable(); | |
42584c81 | 4880 | } |
69abe6a5 | 4881 | |
42584c81 YY |
4882 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
4883 | { | |
4884 | char buf[TASK_COMM_LEN]; | |
4885 | unsigned int *pid = v; | |
69abe6a5 | 4886 | |
4c27e756 | 4887 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
4888 | seq_printf(m, "%d %s\n", *pid, buf); |
4889 | return 0; | |
4890 | } | |
4891 | ||
4892 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
4893 | .start = saved_cmdlines_start, | |
4894 | .next = saved_cmdlines_next, | |
4895 | .stop = saved_cmdlines_stop, | |
4896 | .show = saved_cmdlines_show, | |
4897 | }; | |
4898 | ||
4899 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
4900 | { | |
4901 | if (tracing_disabled) | |
4902 | return -ENODEV; | |
4903 | ||
4904 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
4905 | } |
4906 | ||
4907 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
4908 | .open = tracing_saved_cmdlines_open, |
4909 | .read = seq_read, | |
4910 | .llseek = seq_lseek, | |
4911 | .release = seq_release, | |
69abe6a5 AP |
4912 | }; |
4913 | ||
939c7a4f YY |
4914 | static ssize_t |
4915 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
4916 | size_t cnt, loff_t *ppos) | |
4917 | { | |
4918 | char buf[64]; | |
4919 | int r; | |
4920 | ||
4921 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 4922 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
4923 | arch_spin_unlock(&trace_cmdline_lock); |
4924 | ||
4925 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4926 | } | |
4927 | ||
4928 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
4929 | { | |
4930 | kfree(s->saved_cmdlines); | |
4931 | kfree(s->map_cmdline_to_pid); | |
4932 | kfree(s); | |
4933 | } | |
4934 | ||
4935 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
4936 | { | |
4937 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
4938 | ||
a6af8fbf | 4939 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
4940 | if (!s) |
4941 | return -ENOMEM; | |
4942 | ||
4943 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
4944 | kfree(s); | |
4945 | return -ENOMEM; | |
4946 | } | |
4947 | ||
4948 | arch_spin_lock(&trace_cmdline_lock); | |
4949 | savedcmd_temp = savedcmd; | |
4950 | savedcmd = s; | |
4951 | arch_spin_unlock(&trace_cmdline_lock); | |
4952 | free_saved_cmdlines_buffer(savedcmd_temp); | |
4953 | ||
4954 | return 0; | |
4955 | } | |
4956 | ||
4957 | static ssize_t | |
4958 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
4959 | size_t cnt, loff_t *ppos) | |
4960 | { | |
4961 | unsigned long val; | |
4962 | int ret; | |
4963 | ||
4964 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4965 | if (ret) | |
4966 | return ret; | |
4967 | ||
4968 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
4969 | if (!val || val > PID_MAX_DEFAULT) | |
4970 | return -EINVAL; | |
4971 | ||
4972 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
4973 | if (ret < 0) | |
4974 | return ret; | |
4975 | ||
4976 | *ppos += cnt; | |
4977 | ||
4978 | return cnt; | |
4979 | } | |
4980 | ||
4981 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
4982 | .open = tracing_open_generic, | |
4983 | .read = tracing_saved_cmdlines_size_read, | |
4984 | .write = tracing_saved_cmdlines_size_write, | |
4985 | }; | |
4986 | ||
681bec03 | 4987 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
23bf8cb8 | 4988 | static union trace_eval_map_item * |
f57a4143 | 4989 | update_eval_map(union trace_eval_map_item *ptr) |
9828413d | 4990 | { |
00f4b652 | 4991 | if (!ptr->map.eval_string) { |
9828413d SRRH |
4992 | if (ptr->tail.next) { |
4993 | ptr = ptr->tail.next; | |
4994 | /* Set ptr to the next real item (skip head) */ | |
4995 | ptr++; | |
4996 | } else | |
4997 | return NULL; | |
4998 | } | |
4999 | return ptr; | |
5000 | } | |
5001 | ||
f57a4143 | 5002 | static void *eval_map_next(struct seq_file *m, void *v, loff_t *pos) |
9828413d | 5003 | { |
23bf8cb8 | 5004 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
5005 | |
5006 | /* | |
5007 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
5008 | * This really should never happen. | |
5009 | */ | |
f57a4143 | 5010 | ptr = update_eval_map(ptr); |
9828413d SRRH |
5011 | if (WARN_ON_ONCE(!ptr)) |
5012 | return NULL; | |
5013 | ||
5014 | ptr++; | |
5015 | ||
5016 | (*pos)++; | |
5017 | ||
f57a4143 | 5018 | ptr = update_eval_map(ptr); |
9828413d SRRH |
5019 | |
5020 | return ptr; | |
5021 | } | |
5022 | ||
f57a4143 | 5023 | static void *eval_map_start(struct seq_file *m, loff_t *pos) |
9828413d | 5024 | { |
23bf8cb8 | 5025 | union trace_eval_map_item *v; |
9828413d SRRH |
5026 | loff_t l = 0; |
5027 | ||
1793ed93 | 5028 | mutex_lock(&trace_eval_mutex); |
9828413d | 5029 | |
23bf8cb8 | 5030 | v = trace_eval_maps; |
9828413d SRRH |
5031 | if (v) |
5032 | v++; | |
5033 | ||
5034 | while (v && l < *pos) { | |
f57a4143 | 5035 | v = eval_map_next(m, v, &l); |
9828413d SRRH |
5036 | } |
5037 | ||
5038 | return v; | |
5039 | } | |
5040 | ||
f57a4143 | 5041 | static void eval_map_stop(struct seq_file *m, void *v) |
9828413d | 5042 | { |
1793ed93 | 5043 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
5044 | } |
5045 | ||
f57a4143 | 5046 | static int eval_map_show(struct seq_file *m, void *v) |
9828413d | 5047 | { |
23bf8cb8 | 5048 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
5049 | |
5050 | seq_printf(m, "%s %ld (%s)\n", | |
00f4b652 | 5051 | ptr->map.eval_string, ptr->map.eval_value, |
9828413d SRRH |
5052 | ptr->map.system); |
5053 | ||
5054 | return 0; | |
5055 | } | |
5056 | ||
f57a4143 JL |
5057 | static const struct seq_operations tracing_eval_map_seq_ops = { |
5058 | .start = eval_map_start, | |
5059 | .next = eval_map_next, | |
5060 | .stop = eval_map_stop, | |
5061 | .show = eval_map_show, | |
9828413d SRRH |
5062 | }; |
5063 | ||
f57a4143 | 5064 | static int tracing_eval_map_open(struct inode *inode, struct file *filp) |
9828413d SRRH |
5065 | { |
5066 | if (tracing_disabled) | |
5067 | return -ENODEV; | |
5068 | ||
f57a4143 | 5069 | return seq_open(filp, &tracing_eval_map_seq_ops); |
9828413d SRRH |
5070 | } |
5071 | ||
f57a4143 JL |
5072 | static const struct file_operations tracing_eval_map_fops = { |
5073 | .open = tracing_eval_map_open, | |
9828413d SRRH |
5074 | .read = seq_read, |
5075 | .llseek = seq_lseek, | |
5076 | .release = seq_release, | |
5077 | }; | |
5078 | ||
23bf8cb8 | 5079 | static inline union trace_eval_map_item * |
5f60b351 | 5080 | trace_eval_jmp_to_tail(union trace_eval_map_item *ptr) |
9828413d SRRH |
5081 | { |
5082 | /* Return tail of array given the head */ | |
5083 | return ptr + ptr->head.length + 1; | |
5084 | } | |
5085 | ||
5086 | static void | |
f57a4143 | 5087 | trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start, |
9828413d SRRH |
5088 | int len) |
5089 | { | |
00f4b652 JL |
5090 | struct trace_eval_map **stop; |
5091 | struct trace_eval_map **map; | |
23bf8cb8 JL |
5092 | union trace_eval_map_item *map_array; |
5093 | union trace_eval_map_item *ptr; | |
9828413d SRRH |
5094 | |
5095 | stop = start + len; | |
5096 | ||
5097 | /* | |
23bf8cb8 | 5098 | * The trace_eval_maps contains the map plus a head and tail item, |
9828413d SRRH |
5099 | * where the head holds the module and length of array, and the |
5100 | * tail holds a pointer to the next list. | |
5101 | */ | |
5102 | map_array = kmalloc(sizeof(*map_array) * (len + 2), GFP_KERNEL); | |
5103 | if (!map_array) { | |
f57a4143 | 5104 | pr_warn("Unable to allocate trace eval mapping\n"); |
9828413d SRRH |
5105 | return; |
5106 | } | |
5107 | ||
1793ed93 | 5108 | mutex_lock(&trace_eval_mutex); |
9828413d | 5109 | |
23bf8cb8 JL |
5110 | if (!trace_eval_maps) |
5111 | trace_eval_maps = map_array; | |
9828413d | 5112 | else { |
23bf8cb8 | 5113 | ptr = trace_eval_maps; |
9828413d | 5114 | for (;;) { |
5f60b351 | 5115 | ptr = trace_eval_jmp_to_tail(ptr); |
9828413d SRRH |
5116 | if (!ptr->tail.next) |
5117 | break; | |
5118 | ptr = ptr->tail.next; | |
5119 | ||
5120 | } | |
5121 | ptr->tail.next = map_array; | |
5122 | } | |
5123 | map_array->head.mod = mod; | |
5124 | map_array->head.length = len; | |
5125 | map_array++; | |
5126 | ||
5127 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
5128 | map_array->map = **map; | |
5129 | map_array++; | |
5130 | } | |
5131 | memset(map_array, 0, sizeof(*map_array)); | |
5132 | ||
1793ed93 | 5133 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
5134 | } |
5135 | ||
f57a4143 | 5136 | static void trace_create_eval_file(struct dentry *d_tracer) |
9828413d | 5137 | { |
681bec03 | 5138 | trace_create_file("eval_map", 0444, d_tracer, |
f57a4143 | 5139 | NULL, &tracing_eval_map_fops); |
9828413d SRRH |
5140 | } |
5141 | ||
681bec03 | 5142 | #else /* CONFIG_TRACE_EVAL_MAP_FILE */ |
f57a4143 JL |
5143 | static inline void trace_create_eval_file(struct dentry *d_tracer) { } |
5144 | static inline void trace_insert_eval_map_file(struct module *mod, | |
00f4b652 | 5145 | struct trace_eval_map **start, int len) { } |
681bec03 | 5146 | #endif /* !CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 5147 | |
f57a4143 | 5148 | static void trace_insert_eval_map(struct module *mod, |
00f4b652 | 5149 | struct trace_eval_map **start, int len) |
0c564a53 | 5150 | { |
00f4b652 | 5151 | struct trace_eval_map **map; |
0c564a53 SRRH |
5152 | |
5153 | if (len <= 0) | |
5154 | return; | |
5155 | ||
5156 | map = start; | |
5157 | ||
f57a4143 | 5158 | trace_event_eval_update(map, len); |
9828413d | 5159 | |
f57a4143 | 5160 | trace_insert_eval_map_file(mod, start, len); |
0c564a53 SRRH |
5161 | } |
5162 | ||
bc0c38d1 SR |
5163 | static ssize_t |
5164 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
5165 | size_t cnt, loff_t *ppos) | |
5166 | { | |
2b6080f2 | 5167 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 5168 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
5169 | int r; |
5170 | ||
5171 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5172 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
5173 | mutex_unlock(&trace_types_lock); |
5174 | ||
4bf39a94 | 5175 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
5176 | } |
5177 | ||
b6f11df2 ACM |
5178 | int tracer_init(struct tracer *t, struct trace_array *tr) |
5179 | { | |
12883efb | 5180 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
5181 | return t->init(tr); |
5182 | } | |
5183 | ||
12883efb | 5184 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
5185 | { |
5186 | int cpu; | |
737223fb | 5187 | |
438ced17 | 5188 | for_each_tracing_cpu(cpu) |
12883efb | 5189 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
5190 | } |
5191 | ||
12883efb | 5192 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 5193 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
5194 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
5195 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
5196 | { |
5197 | int cpu, ret = 0; | |
5198 | ||
5199 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
5200 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
5201 | ret = ring_buffer_resize(trace_buf->buffer, |
5202 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
5203 | if (ret < 0) |
5204 | break; | |
12883efb SRRH |
5205 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
5206 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
5207 | } |
5208 | } else { | |
12883efb SRRH |
5209 | ret = ring_buffer_resize(trace_buf->buffer, |
5210 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 5211 | if (ret == 0) |
12883efb SRRH |
5212 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
5213 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
5214 | } |
5215 | ||
5216 | return ret; | |
5217 | } | |
12883efb | 5218 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 5219 | |
2b6080f2 SR |
5220 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
5221 | unsigned long size, int cpu) | |
73c5162a SR |
5222 | { |
5223 | int ret; | |
5224 | ||
5225 | /* | |
5226 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
5227 | * we use the size that was given, and we can forget about |
5228 | * expanding it later. | |
73c5162a | 5229 | */ |
55034cd6 | 5230 | ring_buffer_expanded = true; |
73c5162a | 5231 | |
b382ede6 | 5232 | /* May be called before buffers are initialized */ |
12883efb | 5233 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
5234 | return 0; |
5235 | ||
12883efb | 5236 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
5237 | if (ret < 0) |
5238 | return ret; | |
5239 | ||
12883efb | 5240 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
5241 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
5242 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
5243 | goto out; |
5244 | ||
12883efb | 5245 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 5246 | if (ret < 0) { |
12883efb SRRH |
5247 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
5248 | &tr->trace_buffer, cpu); | |
73c5162a | 5249 | if (r < 0) { |
a123c52b SR |
5250 | /* |
5251 | * AARGH! We are left with different | |
5252 | * size max buffer!!!! | |
5253 | * The max buffer is our "snapshot" buffer. | |
5254 | * When a tracer needs a snapshot (one of the | |
5255 | * latency tracers), it swaps the max buffer | |
5256 | * with the saved snap shot. We succeeded to | |
5257 | * update the size of the main buffer, but failed to | |
5258 | * update the size of the max buffer. But when we tried | |
5259 | * to reset the main buffer to the original size, we | |
5260 | * failed there too. This is very unlikely to | |
5261 | * happen, but if it does, warn and kill all | |
5262 | * tracing. | |
5263 | */ | |
73c5162a SR |
5264 | WARN_ON(1); |
5265 | tracing_disabled = 1; | |
5266 | } | |
5267 | return ret; | |
5268 | } | |
5269 | ||
438ced17 | 5270 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 5271 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 5272 | else |
12883efb | 5273 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 5274 | |
ef710e10 | 5275 | out: |
12883efb SRRH |
5276 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
5277 | ||
438ced17 | 5278 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 5279 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 5280 | else |
12883efb | 5281 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
5282 | |
5283 | return ret; | |
5284 | } | |
5285 | ||
2b6080f2 SR |
5286 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
5287 | unsigned long size, int cpu_id) | |
4f271a2a | 5288 | { |
83f40318 | 5289 | int ret = size; |
4f271a2a VN |
5290 | |
5291 | mutex_lock(&trace_types_lock); | |
5292 | ||
438ced17 VN |
5293 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
5294 | /* make sure, this cpu is enabled in the mask */ | |
5295 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
5296 | ret = -EINVAL; | |
5297 | goto out; | |
5298 | } | |
5299 | } | |
4f271a2a | 5300 | |
2b6080f2 | 5301 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
5302 | if (ret < 0) |
5303 | ret = -ENOMEM; | |
5304 | ||
438ced17 | 5305 | out: |
4f271a2a VN |
5306 | mutex_unlock(&trace_types_lock); |
5307 | ||
5308 | return ret; | |
5309 | } | |
5310 | ||
ef710e10 | 5311 | |
1852fcce SR |
5312 | /** |
5313 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
5314 | * | |
5315 | * To save on memory when the tracing is never used on a system with it | |
5316 | * configured in. The ring buffers are set to a minimum size. But once | |
5317 | * a user starts to use the tracing facility, then they need to grow | |
5318 | * to their default size. | |
5319 | * | |
5320 | * This function is to be called when a tracer is about to be used. | |
5321 | */ | |
5322 | int tracing_update_buffers(void) | |
5323 | { | |
5324 | int ret = 0; | |
5325 | ||
1027fcb2 | 5326 | mutex_lock(&trace_types_lock); |
1852fcce | 5327 | if (!ring_buffer_expanded) |
2b6080f2 | 5328 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 5329 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 5330 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
5331 | |
5332 | return ret; | |
5333 | } | |
5334 | ||
577b785f SR |
5335 | struct trace_option_dentry; |
5336 | ||
37aea98b | 5337 | static void |
2b6080f2 | 5338 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f | 5339 | |
6b450d25 SRRH |
5340 | /* |
5341 | * Used to clear out the tracer before deletion of an instance. | |
5342 | * Must have trace_types_lock held. | |
5343 | */ | |
5344 | static void tracing_set_nop(struct trace_array *tr) | |
5345 | { | |
5346 | if (tr->current_trace == &nop_trace) | |
5347 | return; | |
5348 | ||
50512ab5 | 5349 | tr->current_trace->enabled--; |
6b450d25 SRRH |
5350 | |
5351 | if (tr->current_trace->reset) | |
5352 | tr->current_trace->reset(tr); | |
5353 | ||
5354 | tr->current_trace = &nop_trace; | |
5355 | } | |
5356 | ||
41d9c0be | 5357 | static void add_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 5358 | { |
09d23a1d SRRH |
5359 | /* Only enable if the directory has been created already. */ |
5360 | if (!tr->dir) | |
5361 | return; | |
5362 | ||
37aea98b | 5363 | create_trace_option_files(tr, t); |
09d23a1d SRRH |
5364 | } |
5365 | ||
5366 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) | |
5367 | { | |
bc0c38d1 | 5368 | struct tracer *t; |
12883efb | 5369 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 5370 | bool had_max_tr; |
12883efb | 5371 | #endif |
d9e54076 | 5372 | int ret = 0; |
bc0c38d1 | 5373 | |
1027fcb2 SR |
5374 | mutex_lock(&trace_types_lock); |
5375 | ||
73c5162a | 5376 | if (!ring_buffer_expanded) { |
2b6080f2 | 5377 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 5378 | RING_BUFFER_ALL_CPUS); |
73c5162a | 5379 | if (ret < 0) |
59f586db | 5380 | goto out; |
73c5162a SR |
5381 | ret = 0; |
5382 | } | |
5383 | ||
bc0c38d1 SR |
5384 | for (t = trace_types; t; t = t->next) { |
5385 | if (strcmp(t->name, buf) == 0) | |
5386 | break; | |
5387 | } | |
c2931e05 FW |
5388 | if (!t) { |
5389 | ret = -EINVAL; | |
5390 | goto out; | |
5391 | } | |
2b6080f2 | 5392 | if (t == tr->current_trace) |
bc0c38d1 SR |
5393 | goto out; |
5394 | ||
c7b3ae0b ZSZ |
5395 | /* Some tracers won't work on kernel command line */ |
5396 | if (system_state < SYSTEM_RUNNING && t->noboot) { | |
5397 | pr_warn("Tracer '%s' is not allowed on command line, ignored\n", | |
5398 | t->name); | |
5399 | goto out; | |
5400 | } | |
5401 | ||
607e2ea1 SRRH |
5402 | /* Some tracers are only allowed for the top level buffer */ |
5403 | if (!trace_ok_for_array(t, tr)) { | |
5404 | ret = -EINVAL; | |
5405 | goto out; | |
5406 | } | |
5407 | ||
cf6ab6d9 SRRH |
5408 | /* If trace pipe files are being read, we can't change the tracer */ |
5409 | if (tr->current_trace->ref) { | |
5410 | ret = -EBUSY; | |
5411 | goto out; | |
5412 | } | |
5413 | ||
9f029e83 | 5414 | trace_branch_disable(); |
613f04a0 | 5415 | |
50512ab5 | 5416 | tr->current_trace->enabled--; |
613f04a0 | 5417 | |
2b6080f2 SR |
5418 | if (tr->current_trace->reset) |
5419 | tr->current_trace->reset(tr); | |
34600f0e | 5420 | |
12883efb | 5421 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 5422 | tr->current_trace = &nop_trace; |
34600f0e | 5423 | |
45ad21ca SRRH |
5424 | #ifdef CONFIG_TRACER_MAX_TRACE |
5425 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
5426 | |
5427 | if (had_max_tr && !t->use_max_tr) { | |
5428 | /* | |
5429 | * We need to make sure that the update_max_tr sees that | |
5430 | * current_trace changed to nop_trace to keep it from | |
5431 | * swapping the buffers after we resize it. | |
5432 | * The update_max_tr is called from interrupts disabled | |
5433 | * so a synchronized_sched() is sufficient. | |
5434 | */ | |
5435 | synchronize_sched(); | |
3209cff4 | 5436 | free_snapshot(tr); |
ef710e10 | 5437 | } |
12883efb | 5438 | #endif |
12883efb SRRH |
5439 | |
5440 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 5441 | if (t->use_max_tr && !had_max_tr) { |
c6a95f37 | 5442 | ret = tracing_alloc_snapshot_instance(tr); |
d60da506 HT |
5443 | if (ret < 0) |
5444 | goto out; | |
ef710e10 | 5445 | } |
12883efb | 5446 | #endif |
577b785f | 5447 | |
1c80025a | 5448 | if (t->init) { |
b6f11df2 | 5449 | ret = tracer_init(t, tr); |
1c80025a FW |
5450 | if (ret) |
5451 | goto out; | |
5452 | } | |
bc0c38d1 | 5453 | |
2b6080f2 | 5454 | tr->current_trace = t; |
50512ab5 | 5455 | tr->current_trace->enabled++; |
9f029e83 | 5456 | trace_branch_enable(tr); |
bc0c38d1 SR |
5457 | out: |
5458 | mutex_unlock(&trace_types_lock); | |
5459 | ||
d9e54076 PZ |
5460 | return ret; |
5461 | } | |
5462 | ||
5463 | static ssize_t | |
5464 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
5465 | size_t cnt, loff_t *ppos) | |
5466 | { | |
607e2ea1 | 5467 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 5468 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
5469 | int i; |
5470 | size_t ret; | |
e6e7a65a FW |
5471 | int err; |
5472 | ||
5473 | ret = cnt; | |
d9e54076 | 5474 | |
ee6c2c1b LZ |
5475 | if (cnt > MAX_TRACER_SIZE) |
5476 | cnt = MAX_TRACER_SIZE; | |
d9e54076 | 5477 | |
4afe6495 | 5478 | if (copy_from_user(buf, ubuf, cnt)) |
d9e54076 PZ |
5479 | return -EFAULT; |
5480 | ||
5481 | buf[cnt] = 0; | |
5482 | ||
5483 | /* strip ending whitespace. */ | |
5484 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
5485 | buf[i] = 0; | |
5486 | ||
607e2ea1 | 5487 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
5488 | if (err) |
5489 | return err; | |
d9e54076 | 5490 | |
cf8517cf | 5491 | *ppos += ret; |
bc0c38d1 | 5492 | |
c2931e05 | 5493 | return ret; |
bc0c38d1 SR |
5494 | } |
5495 | ||
5496 | static ssize_t | |
6508fa76 SF |
5497 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
5498 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 5499 | { |
bc0c38d1 SR |
5500 | char buf[64]; |
5501 | int r; | |
5502 | ||
cffae437 | 5503 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 5504 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
5505 | if (r > sizeof(buf)) |
5506 | r = sizeof(buf); | |
4bf39a94 | 5507 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
5508 | } |
5509 | ||
5510 | static ssize_t | |
6508fa76 SF |
5511 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
5512 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 5513 | { |
5e39841c | 5514 | unsigned long val; |
c6caeeb1 | 5515 | int ret; |
bc0c38d1 | 5516 | |
22fe9b54 PH |
5517 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5518 | if (ret) | |
c6caeeb1 | 5519 | return ret; |
bc0c38d1 SR |
5520 | |
5521 | *ptr = val * 1000; | |
5522 | ||
5523 | return cnt; | |
5524 | } | |
5525 | ||
6508fa76 SF |
5526 | static ssize_t |
5527 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
5528 | size_t cnt, loff_t *ppos) | |
5529 | { | |
5530 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
5531 | } | |
5532 | ||
5533 | static ssize_t | |
5534 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
5535 | size_t cnt, loff_t *ppos) | |
5536 | { | |
5537 | struct trace_array *tr = filp->private_data; | |
5538 | int ret; | |
5539 | ||
5540 | mutex_lock(&trace_types_lock); | |
5541 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
5542 | if (ret < 0) | |
5543 | goto out; | |
5544 | ||
5545 | if (tr->current_trace->update_thresh) { | |
5546 | ret = tr->current_trace->update_thresh(tr); | |
5547 | if (ret < 0) | |
5548 | goto out; | |
5549 | } | |
5550 | ||
5551 | ret = cnt; | |
5552 | out: | |
5553 | mutex_unlock(&trace_types_lock); | |
5554 | ||
5555 | return ret; | |
5556 | } | |
5557 | ||
f971cc9a | 5558 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
e428abbb | 5559 | |
6508fa76 SF |
5560 | static ssize_t |
5561 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
5562 | size_t cnt, loff_t *ppos) | |
5563 | { | |
5564 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
5565 | } | |
5566 | ||
5567 | static ssize_t | |
5568 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
5569 | size_t cnt, loff_t *ppos) | |
5570 | { | |
5571 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
5572 | } | |
5573 | ||
e428abbb CG |
5574 | #endif |
5575 | ||
b3806b43 SR |
5576 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
5577 | { | |
15544209 | 5578 | struct trace_array *tr = inode->i_private; |
b3806b43 | 5579 | struct trace_iterator *iter; |
b04cc6b1 | 5580 | int ret = 0; |
b3806b43 SR |
5581 | |
5582 | if (tracing_disabled) | |
5583 | return -ENODEV; | |
5584 | ||
7b85af63 SRRH |
5585 | if (trace_array_get(tr) < 0) |
5586 | return -ENODEV; | |
5587 | ||
b04cc6b1 FW |
5588 | mutex_lock(&trace_types_lock); |
5589 | ||
b3806b43 SR |
5590 | /* create a buffer to store the information to pass to userspace */ |
5591 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
5592 | if (!iter) { |
5593 | ret = -ENOMEM; | |
f77d09a3 | 5594 | __trace_array_put(tr); |
b04cc6b1 FW |
5595 | goto out; |
5596 | } | |
b3806b43 | 5597 | |
3a161d99 | 5598 | trace_seq_init(&iter->seq); |
d716ff71 | 5599 | iter->trace = tr->current_trace; |
d7350c3f | 5600 | |
4462344e | 5601 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 5602 | ret = -ENOMEM; |
d7350c3f | 5603 | goto fail; |
4462344e RR |
5604 | } |
5605 | ||
a309720c | 5606 | /* trace pipe does not show start of buffer */ |
4462344e | 5607 | cpumask_setall(iter->started); |
a309720c | 5608 | |
983f938a | 5609 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
112f38a7 SR |
5610 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
5611 | ||
8be0709f | 5612 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 5613 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
5614 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
5615 | ||
15544209 ON |
5616 | iter->tr = tr; |
5617 | iter->trace_buffer = &tr->trace_buffer; | |
5618 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 5619 | mutex_init(&iter->mutex); |
b3806b43 SR |
5620 | filp->private_data = iter; |
5621 | ||
107bad8b SR |
5622 | if (iter->trace->pipe_open) |
5623 | iter->trace->pipe_open(iter); | |
107bad8b | 5624 | |
b444786f | 5625 | nonseekable_open(inode, filp); |
cf6ab6d9 SRRH |
5626 | |
5627 | tr->current_trace->ref++; | |
b04cc6b1 FW |
5628 | out: |
5629 | mutex_unlock(&trace_types_lock); | |
5630 | return ret; | |
d7350c3f FW |
5631 | |
5632 | fail: | |
d7350c3f | 5633 | kfree(iter); |
7b85af63 | 5634 | __trace_array_put(tr); |
d7350c3f FW |
5635 | mutex_unlock(&trace_types_lock); |
5636 | return ret; | |
b3806b43 SR |
5637 | } |
5638 | ||
5639 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
5640 | { | |
5641 | struct trace_iterator *iter = file->private_data; | |
15544209 | 5642 | struct trace_array *tr = inode->i_private; |
b3806b43 | 5643 | |
b04cc6b1 FW |
5644 | mutex_lock(&trace_types_lock); |
5645 | ||
cf6ab6d9 SRRH |
5646 | tr->current_trace->ref--; |
5647 | ||
29bf4a5e | 5648 | if (iter->trace->pipe_close) |
c521efd1 SR |
5649 | iter->trace->pipe_close(iter); |
5650 | ||
b04cc6b1 FW |
5651 | mutex_unlock(&trace_types_lock); |
5652 | ||
4462344e | 5653 | free_cpumask_var(iter->started); |
d7350c3f | 5654 | mutex_destroy(&iter->mutex); |
b3806b43 | 5655 | kfree(iter); |
b3806b43 | 5656 | |
7b85af63 SRRH |
5657 | trace_array_put(tr); |
5658 | ||
b3806b43 SR |
5659 | return 0; |
5660 | } | |
5661 | ||
2a2cc8f7 | 5662 | static unsigned int |
cc60cdc9 | 5663 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 5664 | { |
983f938a SRRH |
5665 | struct trace_array *tr = iter->tr; |
5666 | ||
15693458 SRRH |
5667 | /* Iterators are static, they should be filled or empty */ |
5668 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
5669 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 5670 | |
983f938a | 5671 | if (tr->trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
5672 | /* |
5673 | * Always select as readable when in blocking mode | |
5674 | */ | |
5675 | return POLLIN | POLLRDNORM; | |
15693458 | 5676 | else |
12883efb | 5677 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 5678 | filp, poll_table); |
2a2cc8f7 | 5679 | } |
2a2cc8f7 | 5680 | |
cc60cdc9 SR |
5681 | static unsigned int |
5682 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
5683 | { | |
5684 | struct trace_iterator *iter = filp->private_data; | |
5685 | ||
5686 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
5687 | } |
5688 | ||
d716ff71 | 5689 | /* Must be called with iter->mutex held. */ |
ff98781b | 5690 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
5691 | { |
5692 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 5693 | int ret; |
b3806b43 | 5694 | |
b3806b43 | 5695 | while (trace_empty(iter)) { |
2dc8f095 | 5696 | |
107bad8b | 5697 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 5698 | return -EAGAIN; |
107bad8b | 5699 | } |
2dc8f095 | 5700 | |
b3806b43 | 5701 | /* |
250bfd3d | 5702 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
5703 | * We still block if tracing is disabled, but we have never |
5704 | * read anything. This allows a user to cat this file, and | |
5705 | * then enable tracing. But after we have read something, | |
5706 | * we give an EOF when tracing is again disabled. | |
5707 | * | |
5708 | * iter->pos will be 0 if we haven't read anything. | |
5709 | */ | |
75df6e68 | 5710 | if (!tracer_tracing_is_on(iter->tr) && iter->pos) |
b3806b43 | 5711 | break; |
f4874261 SRRH |
5712 | |
5713 | mutex_unlock(&iter->mutex); | |
5714 | ||
e30f53aa | 5715 | ret = wait_on_pipe(iter, false); |
f4874261 SRRH |
5716 | |
5717 | mutex_lock(&iter->mutex); | |
5718 | ||
8b8b3683 SRRH |
5719 | if (ret) |
5720 | return ret; | |
b3806b43 SR |
5721 | } |
5722 | ||
ff98781b EGM |
5723 | return 1; |
5724 | } | |
5725 | ||
5726 | /* | |
5727 | * Consumer reader. | |
5728 | */ | |
5729 | static ssize_t | |
5730 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
5731 | size_t cnt, loff_t *ppos) | |
5732 | { | |
5733 | struct trace_iterator *iter = filp->private_data; | |
5734 | ssize_t sret; | |
5735 | ||
d7350c3f FW |
5736 | /* |
5737 | * Avoid more than one consumer on a single file descriptor | |
5738 | * This is just a matter of traces coherency, the ring buffer itself | |
5739 | * is protected. | |
5740 | */ | |
5741 | mutex_lock(&iter->mutex); | |
1245800c SRRH |
5742 | |
5743 | /* return any leftover data */ | |
5744 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
5745 | if (sret != -EBUSY) | |
5746 | goto out; | |
5747 | ||
5748 | trace_seq_init(&iter->seq); | |
5749 | ||
ff98781b EGM |
5750 | if (iter->trace->read) { |
5751 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
5752 | if (sret) | |
5753 | goto out; | |
5754 | } | |
5755 | ||
5756 | waitagain: | |
5757 | sret = tracing_wait_pipe(filp); | |
5758 | if (sret <= 0) | |
5759 | goto out; | |
5760 | ||
b3806b43 | 5761 | /* stop when tracing is finished */ |
ff98781b EGM |
5762 | if (trace_empty(iter)) { |
5763 | sret = 0; | |
107bad8b | 5764 | goto out; |
ff98781b | 5765 | } |
b3806b43 SR |
5766 | |
5767 | if (cnt >= PAGE_SIZE) | |
5768 | cnt = PAGE_SIZE - 1; | |
5769 | ||
53d0aa77 | 5770 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
5771 | memset(&iter->seq, 0, |
5772 | sizeof(struct trace_iterator) - | |
5773 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 5774 | cpumask_clear(iter->started); |
2a7ad49a | 5775 | trace_seq_init(&iter->seq); |
4823ed7e | 5776 | iter->pos = -1; |
b3806b43 | 5777 | |
4f535968 | 5778 | trace_event_read_lock(); |
7e53bd42 | 5779 | trace_access_lock(iter->cpu_file); |
955b61e5 | 5780 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 5781 | enum print_line_t ret; |
5ac48378 | 5782 | int save_len = iter->seq.seq.len; |
088b1e42 | 5783 | |
f9896bf3 | 5784 | ret = print_trace_line(iter); |
2c4f035f | 5785 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 5786 | /* don't print partial lines */ |
5ac48378 | 5787 | iter->seq.seq.len = save_len; |
b3806b43 | 5788 | break; |
088b1e42 | 5789 | } |
b91facc3 FW |
5790 | if (ret != TRACE_TYPE_NO_CONSUME) |
5791 | trace_consume(iter); | |
b3806b43 | 5792 | |
5ac48378 | 5793 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 5794 | break; |
ee5e51f5 JO |
5795 | |
5796 | /* | |
5797 | * Setting the full flag means we reached the trace_seq buffer | |
5798 | * size and we should leave by partial output condition above. | |
5799 | * One of the trace_seq_* functions is not used properly. | |
5800 | */ | |
5801 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
5802 | iter->ent->type); | |
b3806b43 | 5803 | } |
7e53bd42 | 5804 | trace_access_unlock(iter->cpu_file); |
4f535968 | 5805 | trace_event_read_unlock(); |
b3806b43 | 5806 | |
b3806b43 | 5807 | /* Now copy what we have to the user */ |
6c6c2796 | 5808 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 5809 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 5810 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
5811 | |
5812 | /* | |
25985edc | 5813 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
5814 | * entries, go back to wait for more entries. |
5815 | */ | |
6c6c2796 | 5816 | if (sret == -EBUSY) |
9ff4b974 | 5817 | goto waitagain; |
b3806b43 | 5818 | |
107bad8b | 5819 | out: |
d7350c3f | 5820 | mutex_unlock(&iter->mutex); |
107bad8b | 5821 | |
6c6c2796 | 5822 | return sret; |
b3806b43 SR |
5823 | } |
5824 | ||
3c56819b EGM |
5825 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
5826 | unsigned int idx) | |
5827 | { | |
5828 | __free_page(spd->pages[idx]); | |
5829 | } | |
5830 | ||
28dfef8f | 5831 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 5832 | .can_merge = 0, |
34cd4998 | 5833 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 5834 | .release = generic_pipe_buf_release, |
34cd4998 SR |
5835 | .steal = generic_pipe_buf_steal, |
5836 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
5837 | }; |
5838 | ||
34cd4998 | 5839 | static size_t |
fa7c7f6e | 5840 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
5841 | { |
5842 | size_t count; | |
74f06bb7 | 5843 | int save_len; |
34cd4998 SR |
5844 | int ret; |
5845 | ||
5846 | /* Seq buffer is page-sized, exactly what we need. */ | |
5847 | for (;;) { | |
74f06bb7 | 5848 | save_len = iter->seq.seq.len; |
34cd4998 | 5849 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
5850 | |
5851 | if (trace_seq_has_overflowed(&iter->seq)) { | |
5852 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
5853 | break; |
5854 | } | |
74f06bb7 SRRH |
5855 | |
5856 | /* | |
5857 | * This should not be hit, because it should only | |
5858 | * be set if the iter->seq overflowed. But check it | |
5859 | * anyway to be safe. | |
5860 | */ | |
34cd4998 | 5861 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
5862 | iter->seq.seq.len = save_len; |
5863 | break; | |
5864 | } | |
5865 | ||
5ac48378 | 5866 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
5867 | if (rem < count) { |
5868 | rem = 0; | |
5869 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
5870 | break; |
5871 | } | |
5872 | ||
74e7ff8c LJ |
5873 | if (ret != TRACE_TYPE_NO_CONSUME) |
5874 | trace_consume(iter); | |
34cd4998 | 5875 | rem -= count; |
955b61e5 | 5876 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
5877 | rem = 0; |
5878 | iter->ent = NULL; | |
5879 | break; | |
5880 | } | |
5881 | } | |
5882 | ||
5883 | return rem; | |
5884 | } | |
5885 | ||
3c56819b EGM |
5886 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
5887 | loff_t *ppos, | |
5888 | struct pipe_inode_info *pipe, | |
5889 | size_t len, | |
5890 | unsigned int flags) | |
5891 | { | |
35f3d14d JA |
5892 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
5893 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
5894 | struct trace_iterator *iter = filp->private_data; |
5895 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
5896 | .pages = pages_def, |
5897 | .partial = partial_def, | |
34cd4998 | 5898 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 5899 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
5900 | .ops = &tracing_pipe_buf_ops, |
5901 | .spd_release = tracing_spd_release_pipe, | |
3c56819b EGM |
5902 | }; |
5903 | ssize_t ret; | |
34cd4998 | 5904 | size_t rem; |
3c56819b EGM |
5905 | unsigned int i; |
5906 | ||
35f3d14d JA |
5907 | if (splice_grow_spd(pipe, &spd)) |
5908 | return -ENOMEM; | |
5909 | ||
d7350c3f | 5910 | mutex_lock(&iter->mutex); |
3c56819b EGM |
5911 | |
5912 | if (iter->trace->splice_read) { | |
5913 | ret = iter->trace->splice_read(iter, filp, | |
5914 | ppos, pipe, len, flags); | |
5915 | if (ret) | |
34cd4998 | 5916 | goto out_err; |
3c56819b EGM |
5917 | } |
5918 | ||
5919 | ret = tracing_wait_pipe(filp); | |
5920 | if (ret <= 0) | |
34cd4998 | 5921 | goto out_err; |
3c56819b | 5922 | |
955b61e5 | 5923 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 5924 | ret = -EFAULT; |
34cd4998 | 5925 | goto out_err; |
3c56819b EGM |
5926 | } |
5927 | ||
4f535968 | 5928 | trace_event_read_lock(); |
7e53bd42 | 5929 | trace_access_lock(iter->cpu_file); |
4f535968 | 5930 | |
3c56819b | 5931 | /* Fill as many pages as possible. */ |
a786c06d | 5932 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
5933 | spd.pages[i] = alloc_page(GFP_KERNEL); |
5934 | if (!spd.pages[i]) | |
34cd4998 | 5935 | break; |
3c56819b | 5936 | |
fa7c7f6e | 5937 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
5938 | |
5939 | /* Copy the data into the page, so we can start over. */ | |
5940 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 5941 | page_address(spd.pages[i]), |
5ac48378 | 5942 | trace_seq_used(&iter->seq)); |
3c56819b | 5943 | if (ret < 0) { |
35f3d14d | 5944 | __free_page(spd.pages[i]); |
3c56819b EGM |
5945 | break; |
5946 | } | |
35f3d14d | 5947 | spd.partial[i].offset = 0; |
5ac48378 | 5948 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 5949 | |
f9520750 | 5950 | trace_seq_init(&iter->seq); |
3c56819b EGM |
5951 | } |
5952 | ||
7e53bd42 | 5953 | trace_access_unlock(iter->cpu_file); |
4f535968 | 5954 | trace_event_read_unlock(); |
d7350c3f | 5955 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
5956 | |
5957 | spd.nr_pages = i; | |
5958 | ||
a29054d9 SRRH |
5959 | if (i) |
5960 | ret = splice_to_pipe(pipe, &spd); | |
5961 | else | |
5962 | ret = 0; | |
35f3d14d | 5963 | out: |
047fe360 | 5964 | splice_shrink_spd(&spd); |
35f3d14d | 5965 | return ret; |
3c56819b | 5966 | |
34cd4998 | 5967 | out_err: |
d7350c3f | 5968 | mutex_unlock(&iter->mutex); |
35f3d14d | 5969 | goto out; |
3c56819b EGM |
5970 | } |
5971 | ||
a98a3c3f SR |
5972 | static ssize_t |
5973 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
5974 | size_t cnt, loff_t *ppos) | |
5975 | { | |
0bc392ee ON |
5976 | struct inode *inode = file_inode(filp); |
5977 | struct trace_array *tr = inode->i_private; | |
5978 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
5979 | char buf[64]; |
5980 | int r = 0; | |
5981 | ssize_t ret; | |
a98a3c3f | 5982 | |
db526ca3 | 5983 | mutex_lock(&trace_types_lock); |
438ced17 | 5984 | |
0bc392ee | 5985 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
5986 | int cpu, buf_size_same; |
5987 | unsigned long size; | |
5988 | ||
5989 | size = 0; | |
5990 | buf_size_same = 1; | |
5991 | /* check if all cpu sizes are same */ | |
5992 | for_each_tracing_cpu(cpu) { | |
5993 | /* fill in the size from first enabled cpu */ | |
5994 | if (size == 0) | |
12883efb SRRH |
5995 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
5996 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
5997 | buf_size_same = 0; |
5998 | break; | |
5999 | } | |
6000 | } | |
6001 | ||
6002 | if (buf_size_same) { | |
6003 | if (!ring_buffer_expanded) | |
6004 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
6005 | size >> 10, | |
6006 | trace_buf_size >> 10); | |
6007 | else | |
6008 | r = sprintf(buf, "%lu\n", size >> 10); | |
6009 | } else | |
6010 | r = sprintf(buf, "X\n"); | |
6011 | } else | |
0bc392ee | 6012 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 6013 | |
db526ca3 SR |
6014 | mutex_unlock(&trace_types_lock); |
6015 | ||
438ced17 VN |
6016 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
6017 | return ret; | |
a98a3c3f SR |
6018 | } |
6019 | ||
6020 | static ssize_t | |
6021 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
6022 | size_t cnt, loff_t *ppos) | |
6023 | { | |
0bc392ee ON |
6024 | struct inode *inode = file_inode(filp); |
6025 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 6026 | unsigned long val; |
4f271a2a | 6027 | int ret; |
a98a3c3f | 6028 | |
22fe9b54 PH |
6029 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6030 | if (ret) | |
c6caeeb1 | 6031 | return ret; |
a98a3c3f SR |
6032 | |
6033 | /* must have at least 1 entry */ | |
6034 | if (!val) | |
6035 | return -EINVAL; | |
6036 | ||
1696b2b0 SR |
6037 | /* value is in KB */ |
6038 | val <<= 10; | |
0bc392ee | 6039 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
6040 | if (ret < 0) |
6041 | return ret; | |
a98a3c3f | 6042 | |
cf8517cf | 6043 | *ppos += cnt; |
a98a3c3f | 6044 | |
4f271a2a VN |
6045 | return cnt; |
6046 | } | |
bf5e6519 | 6047 | |
f81ab074 VN |
6048 | static ssize_t |
6049 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
6050 | size_t cnt, loff_t *ppos) | |
6051 | { | |
6052 | struct trace_array *tr = filp->private_data; | |
6053 | char buf[64]; | |
6054 | int r, cpu; | |
6055 | unsigned long size = 0, expanded_size = 0; | |
6056 | ||
6057 | mutex_lock(&trace_types_lock); | |
6058 | for_each_tracing_cpu(cpu) { | |
12883efb | 6059 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
6060 | if (!ring_buffer_expanded) |
6061 | expanded_size += trace_buf_size >> 10; | |
6062 | } | |
6063 | if (ring_buffer_expanded) | |
6064 | r = sprintf(buf, "%lu\n", size); | |
6065 | else | |
6066 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
6067 | mutex_unlock(&trace_types_lock); | |
6068 | ||
6069 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6070 | } | |
6071 | ||
4f271a2a VN |
6072 | static ssize_t |
6073 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
6074 | size_t cnt, loff_t *ppos) | |
6075 | { | |
6076 | /* | |
6077 | * There is no need to read what the user has written, this function | |
6078 | * is just to make sure that there is no error when "echo" is used | |
6079 | */ | |
6080 | ||
6081 | *ppos += cnt; | |
a98a3c3f SR |
6082 | |
6083 | return cnt; | |
6084 | } | |
6085 | ||
4f271a2a VN |
6086 | static int |
6087 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
6088 | { | |
2b6080f2 SR |
6089 | struct trace_array *tr = inode->i_private; |
6090 | ||
cf30cf67 | 6091 | /* disable tracing ? */ |
983f938a | 6092 | if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) |
711e1243 | 6093 | tracer_tracing_off(tr); |
4f271a2a | 6094 | /* resize the ring buffer to 0 */ |
2b6080f2 | 6095 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 6096 | |
7b85af63 SRRH |
6097 | trace_array_put(tr); |
6098 | ||
4f271a2a VN |
6099 | return 0; |
6100 | } | |
6101 | ||
5bf9a1ee PP |
6102 | static ssize_t |
6103 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
6104 | size_t cnt, loff_t *fpos) | |
6105 | { | |
2d71619c | 6106 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
6107 | struct ring_buffer_event *event; |
6108 | struct ring_buffer *buffer; | |
6109 | struct print_entry *entry; | |
6110 | unsigned long irq_flags; | |
656c7f0d | 6111 | const char faulted[] = "<faulted>"; |
d696b58c | 6112 | ssize_t written; |
d696b58c SR |
6113 | int size; |
6114 | int len; | |
fa32e855 | 6115 | |
656c7f0d SRRH |
6116 | /* Used in tracing_mark_raw_write() as well */ |
6117 | #define FAULTED_SIZE (sizeof(faulted) - 1) /* '\0' is already accounted for */ | |
5bf9a1ee | 6118 | |
c76f0694 | 6119 | if (tracing_disabled) |
5bf9a1ee PP |
6120 | return -EINVAL; |
6121 | ||
983f938a | 6122 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) |
5224c3a3 MSB |
6123 | return -EINVAL; |
6124 | ||
5bf9a1ee PP |
6125 | if (cnt > TRACE_BUF_SIZE) |
6126 | cnt = TRACE_BUF_SIZE; | |
6127 | ||
d696b58c | 6128 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); |
5bf9a1ee | 6129 | |
d696b58c | 6130 | local_save_flags(irq_flags); |
656c7f0d | 6131 | size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */ |
d696b58c | 6132 | |
656c7f0d SRRH |
6133 | /* If less than "<faulted>", then make sure we can still add that */ |
6134 | if (cnt < FAULTED_SIZE) | |
6135 | size += FAULTED_SIZE - cnt; | |
d696b58c | 6136 | |
2d71619c | 6137 | buffer = tr->trace_buffer.buffer; |
3e9a8aad SRRH |
6138 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
6139 | irq_flags, preempt_count()); | |
656c7f0d | 6140 | if (unlikely(!event)) |
d696b58c | 6141 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 6142 | return -EBADF; |
d696b58c SR |
6143 | |
6144 | entry = ring_buffer_event_data(event); | |
6145 | entry->ip = _THIS_IP_; | |
6146 | ||
656c7f0d SRRH |
6147 | len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt); |
6148 | if (len) { | |
6149 | memcpy(&entry->buf, faulted, FAULTED_SIZE); | |
6150 | cnt = FAULTED_SIZE; | |
6151 | written = -EFAULT; | |
c13d2f7c | 6152 | } else |
656c7f0d SRRH |
6153 | written = cnt; |
6154 | len = cnt; | |
5bf9a1ee | 6155 | |
d696b58c SR |
6156 | if (entry->buf[cnt - 1] != '\n') { |
6157 | entry->buf[cnt] = '\n'; | |
6158 | entry->buf[cnt + 1] = '\0'; | |
6159 | } else | |
6160 | entry->buf[cnt] = '\0'; | |
6161 | ||
7ffbd48d | 6162 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 6163 | |
656c7f0d SRRH |
6164 | if (written > 0) |
6165 | *fpos += written; | |
5bf9a1ee | 6166 | |
fa32e855 SR |
6167 | return written; |
6168 | } | |
6169 | ||
6170 | /* Limit it for now to 3K (including tag) */ | |
6171 | #define RAW_DATA_MAX_SIZE (1024*3) | |
6172 | ||
6173 | static ssize_t | |
6174 | tracing_mark_raw_write(struct file *filp, const char __user *ubuf, | |
6175 | size_t cnt, loff_t *fpos) | |
6176 | { | |
6177 | struct trace_array *tr = filp->private_data; | |
6178 | struct ring_buffer_event *event; | |
6179 | struct ring_buffer *buffer; | |
6180 | struct raw_data_entry *entry; | |
656c7f0d | 6181 | const char faulted[] = "<faulted>"; |
fa32e855 | 6182 | unsigned long irq_flags; |
fa32e855 | 6183 | ssize_t written; |
fa32e855 SR |
6184 | int size; |
6185 | int len; | |
6186 | ||
656c7f0d SRRH |
6187 | #define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int)) |
6188 | ||
fa32e855 SR |
6189 | if (tracing_disabled) |
6190 | return -EINVAL; | |
6191 | ||
6192 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) | |
6193 | return -EINVAL; | |
6194 | ||
6195 | /* The marker must at least have a tag id */ | |
6196 | if (cnt < sizeof(unsigned int) || cnt > RAW_DATA_MAX_SIZE) | |
6197 | return -EINVAL; | |
6198 | ||
6199 | if (cnt > TRACE_BUF_SIZE) | |
6200 | cnt = TRACE_BUF_SIZE; | |
6201 | ||
6202 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
6203 | ||
fa32e855 SR |
6204 | local_save_flags(irq_flags); |
6205 | size = sizeof(*entry) + cnt; | |
656c7f0d SRRH |
6206 | if (cnt < FAULT_SIZE_ID) |
6207 | size += FAULT_SIZE_ID - cnt; | |
6208 | ||
fa32e855 | 6209 | buffer = tr->trace_buffer.buffer; |
3e9a8aad SRRH |
6210 | event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size, |
6211 | irq_flags, preempt_count()); | |
656c7f0d | 6212 | if (!event) |
fa32e855 | 6213 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 6214 | return -EBADF; |
fa32e855 SR |
6215 | |
6216 | entry = ring_buffer_event_data(event); | |
6217 | ||
656c7f0d SRRH |
6218 | len = __copy_from_user_inatomic(&entry->id, ubuf, cnt); |
6219 | if (len) { | |
6220 | entry->id = -1; | |
6221 | memcpy(&entry->buf, faulted, FAULTED_SIZE); | |
6222 | written = -EFAULT; | |
fa32e855 | 6223 | } else |
656c7f0d | 6224 | written = cnt; |
fa32e855 SR |
6225 | |
6226 | __buffer_unlock_commit(buffer, event); | |
6227 | ||
656c7f0d SRRH |
6228 | if (written > 0) |
6229 | *fpos += written; | |
1aa54bca MS |
6230 | |
6231 | return written; | |
5bf9a1ee PP |
6232 | } |
6233 | ||
13f16d20 | 6234 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 6235 | { |
2b6080f2 | 6236 | struct trace_array *tr = m->private; |
5079f326 Z |
6237 | int i; |
6238 | ||
6239 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 6240 | seq_printf(m, |
5079f326 | 6241 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
6242 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
6243 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 6244 | seq_putc(m, '\n'); |
5079f326 | 6245 | |
13f16d20 | 6246 | return 0; |
5079f326 Z |
6247 | } |
6248 | ||
e1e232ca | 6249 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 6250 | { |
5079f326 Z |
6251 | int i; |
6252 | ||
5079f326 Z |
6253 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
6254 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
6255 | break; | |
6256 | } | |
6257 | if (i == ARRAY_SIZE(trace_clocks)) | |
6258 | return -EINVAL; | |
6259 | ||
5079f326 Z |
6260 | mutex_lock(&trace_types_lock); |
6261 | ||
2b6080f2 SR |
6262 | tr->clock_id = i; |
6263 | ||
12883efb | 6264 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 6265 | |
60303ed3 DS |
6266 | /* |
6267 | * New clock may not be consistent with the previous clock. | |
6268 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
6269 | */ | |
9457158b | 6270 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
6271 | |
6272 | #ifdef CONFIG_TRACER_MAX_TRACE | |
170b3b10 | 6273 | if (tr->max_buffer.buffer) |
12883efb | 6274 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); |
9457158b | 6275 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 6276 | #endif |
60303ed3 | 6277 | |
5079f326 Z |
6278 | mutex_unlock(&trace_types_lock); |
6279 | ||
e1e232ca SR |
6280 | return 0; |
6281 | } | |
6282 | ||
6283 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
6284 | size_t cnt, loff_t *fpos) | |
6285 | { | |
6286 | struct seq_file *m = filp->private_data; | |
6287 | struct trace_array *tr = m->private; | |
6288 | char buf[64]; | |
6289 | const char *clockstr; | |
6290 | int ret; | |
6291 | ||
6292 | if (cnt >= sizeof(buf)) | |
6293 | return -EINVAL; | |
6294 | ||
4afe6495 | 6295 | if (copy_from_user(buf, ubuf, cnt)) |
e1e232ca SR |
6296 | return -EFAULT; |
6297 | ||
6298 | buf[cnt] = 0; | |
6299 | ||
6300 | clockstr = strstrip(buf); | |
6301 | ||
6302 | ret = tracing_set_clock(tr, clockstr); | |
6303 | if (ret) | |
6304 | return ret; | |
6305 | ||
5079f326 Z |
6306 | *fpos += cnt; |
6307 | ||
6308 | return cnt; | |
6309 | } | |
6310 | ||
13f16d20 LZ |
6311 | static int tracing_clock_open(struct inode *inode, struct file *file) |
6312 | { | |
7b85af63 SRRH |
6313 | struct trace_array *tr = inode->i_private; |
6314 | int ret; | |
6315 | ||
13f16d20 LZ |
6316 | if (tracing_disabled) |
6317 | return -ENODEV; | |
2b6080f2 | 6318 | |
7b85af63 SRRH |
6319 | if (trace_array_get(tr)) |
6320 | return -ENODEV; | |
6321 | ||
6322 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
6323 | if (ret < 0) | |
6324 | trace_array_put(tr); | |
6325 | ||
6326 | return ret; | |
13f16d20 LZ |
6327 | } |
6328 | ||
6de58e62 SRRH |
6329 | struct ftrace_buffer_info { |
6330 | struct trace_iterator iter; | |
6331 | void *spare; | |
73a757e6 | 6332 | unsigned int spare_cpu; |
6de58e62 SRRH |
6333 | unsigned int read; |
6334 | }; | |
6335 | ||
debdd57f HT |
6336 | #ifdef CONFIG_TRACER_SNAPSHOT |
6337 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
6338 | { | |
6484c71c | 6339 | struct trace_array *tr = inode->i_private; |
debdd57f | 6340 | struct trace_iterator *iter; |
2b6080f2 | 6341 | struct seq_file *m; |
debdd57f HT |
6342 | int ret = 0; |
6343 | ||
ff451961 SRRH |
6344 | if (trace_array_get(tr) < 0) |
6345 | return -ENODEV; | |
6346 | ||
debdd57f | 6347 | if (file->f_mode & FMODE_READ) { |
6484c71c | 6348 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
6349 | if (IS_ERR(iter)) |
6350 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
6351 | } else { |
6352 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 6353 | ret = -ENOMEM; |
2b6080f2 SR |
6354 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
6355 | if (!m) | |
f77d09a3 | 6356 | goto out; |
2b6080f2 SR |
6357 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
6358 | if (!iter) { | |
6359 | kfree(m); | |
f77d09a3 | 6360 | goto out; |
2b6080f2 | 6361 | } |
f77d09a3 AL |
6362 | ret = 0; |
6363 | ||
ff451961 | 6364 | iter->tr = tr; |
6484c71c ON |
6365 | iter->trace_buffer = &tr->max_buffer; |
6366 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
6367 | m->private = iter; |
6368 | file->private_data = m; | |
debdd57f | 6369 | } |
f77d09a3 | 6370 | out: |
ff451961 SRRH |
6371 | if (ret < 0) |
6372 | trace_array_put(tr); | |
6373 | ||
debdd57f HT |
6374 | return ret; |
6375 | } | |
6376 | ||
6377 | static ssize_t | |
6378 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6379 | loff_t *ppos) | |
6380 | { | |
2b6080f2 SR |
6381 | struct seq_file *m = filp->private_data; |
6382 | struct trace_iterator *iter = m->private; | |
6383 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
6384 | unsigned long val; |
6385 | int ret; | |
6386 | ||
6387 | ret = tracing_update_buffers(); | |
6388 | if (ret < 0) | |
6389 | return ret; | |
6390 | ||
6391 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6392 | if (ret) | |
6393 | return ret; | |
6394 | ||
6395 | mutex_lock(&trace_types_lock); | |
6396 | ||
2b6080f2 | 6397 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
6398 | ret = -EBUSY; |
6399 | goto out; | |
6400 | } | |
6401 | ||
6402 | switch (val) { | |
6403 | case 0: | |
f1affcaa SRRH |
6404 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
6405 | ret = -EINVAL; | |
6406 | break; | |
debdd57f | 6407 | } |
3209cff4 SRRH |
6408 | if (tr->allocated_snapshot) |
6409 | free_snapshot(tr); | |
debdd57f HT |
6410 | break; |
6411 | case 1: | |
f1affcaa SRRH |
6412 | /* Only allow per-cpu swap if the ring buffer supports it */ |
6413 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
6414 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
6415 | ret = -EINVAL; | |
6416 | break; | |
6417 | } | |
6418 | #endif | |
90b89546 ET |
6419 | if (tr->allocated_snapshot) |
6420 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
6421 | &tr->trace_buffer, iter->cpu_file); | |
6422 | else | |
c6a95f37 | 6423 | ret = tracing_alloc_snapshot_instance(tr); |
90b89546 ET |
6424 | if (ret < 0) |
6425 | break; | |
debdd57f HT |
6426 | local_irq_disable(); |
6427 | /* Now, we're going to swap */ | |
f1affcaa | 6428 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 6429 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 6430 | else |
ce9bae55 | 6431 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
6432 | local_irq_enable(); |
6433 | break; | |
6434 | default: | |
45ad21ca | 6435 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
6436 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
6437 | tracing_reset_online_cpus(&tr->max_buffer); | |
6438 | else | |
6439 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
6440 | } | |
debdd57f HT |
6441 | break; |
6442 | } | |
6443 | ||
6444 | if (ret >= 0) { | |
6445 | *ppos += cnt; | |
6446 | ret = cnt; | |
6447 | } | |
6448 | out: | |
6449 | mutex_unlock(&trace_types_lock); | |
6450 | return ret; | |
6451 | } | |
2b6080f2 SR |
6452 | |
6453 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
6454 | { | |
6455 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
6456 | int ret; |
6457 | ||
6458 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
6459 | |
6460 | if (file->f_mode & FMODE_READ) | |
ff451961 | 6461 | return ret; |
2b6080f2 SR |
6462 | |
6463 | /* If write only, the seq_file is just a stub */ | |
6464 | if (m) | |
6465 | kfree(m->private); | |
6466 | kfree(m); | |
6467 | ||
6468 | return 0; | |
6469 | } | |
6470 | ||
6de58e62 SRRH |
6471 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
6472 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
6473 | size_t count, loff_t *ppos); | |
6474 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
6475 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
6476 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
6477 | ||
6478 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
6479 | { | |
6480 | struct ftrace_buffer_info *info; | |
6481 | int ret; | |
6482 | ||
6483 | ret = tracing_buffers_open(inode, filp); | |
6484 | if (ret < 0) | |
6485 | return ret; | |
6486 | ||
6487 | info = filp->private_data; | |
6488 | ||
6489 | if (info->iter.trace->use_max_tr) { | |
6490 | tracing_buffers_release(inode, filp); | |
6491 | return -EBUSY; | |
6492 | } | |
6493 | ||
6494 | info->iter.snapshot = true; | |
6495 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
6496 | ||
6497 | return ret; | |
6498 | } | |
6499 | ||
debdd57f HT |
6500 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
6501 | ||
6502 | ||
6508fa76 SF |
6503 | static const struct file_operations tracing_thresh_fops = { |
6504 | .open = tracing_open_generic, | |
6505 | .read = tracing_thresh_read, | |
6506 | .write = tracing_thresh_write, | |
6507 | .llseek = generic_file_llseek, | |
6508 | }; | |
6509 | ||
f971cc9a | 6510 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
5e2336a0 | 6511 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
6512 | .open = tracing_open_generic, |
6513 | .read = tracing_max_lat_read, | |
6514 | .write = tracing_max_lat_write, | |
b444786f | 6515 | .llseek = generic_file_llseek, |
bc0c38d1 | 6516 | }; |
e428abbb | 6517 | #endif |
bc0c38d1 | 6518 | |
5e2336a0 | 6519 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
6520 | .open = tracing_open_generic, |
6521 | .read = tracing_set_trace_read, | |
6522 | .write = tracing_set_trace_write, | |
b444786f | 6523 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
6524 | }; |
6525 | ||
5e2336a0 | 6526 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 6527 | .open = tracing_open_pipe, |
2a2cc8f7 | 6528 | .poll = tracing_poll_pipe, |
4bf39a94 | 6529 | .read = tracing_read_pipe, |
3c56819b | 6530 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 6531 | .release = tracing_release_pipe, |
b444786f | 6532 | .llseek = no_llseek, |
b3806b43 SR |
6533 | }; |
6534 | ||
5e2336a0 | 6535 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 6536 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
6537 | .read = tracing_entries_read, |
6538 | .write = tracing_entries_write, | |
b444786f | 6539 | .llseek = generic_file_llseek, |
0bc392ee | 6540 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
6541 | }; |
6542 | ||
f81ab074 | 6543 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 6544 | .open = tracing_open_generic_tr, |
f81ab074 VN |
6545 | .read = tracing_total_entries_read, |
6546 | .llseek = generic_file_llseek, | |
7b85af63 | 6547 | .release = tracing_release_generic_tr, |
f81ab074 VN |
6548 | }; |
6549 | ||
4f271a2a | 6550 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 6551 | .open = tracing_open_generic_tr, |
4f271a2a VN |
6552 | .write = tracing_free_buffer_write, |
6553 | .release = tracing_free_buffer_release, | |
6554 | }; | |
6555 | ||
5e2336a0 | 6556 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 6557 | .open = tracing_open_generic_tr, |
5bf9a1ee | 6558 | .write = tracing_mark_write, |
b444786f | 6559 | .llseek = generic_file_llseek, |
7b85af63 | 6560 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
6561 | }; |
6562 | ||
fa32e855 SR |
6563 | static const struct file_operations tracing_mark_raw_fops = { |
6564 | .open = tracing_open_generic_tr, | |
6565 | .write = tracing_mark_raw_write, | |
6566 | .llseek = generic_file_llseek, | |
6567 | .release = tracing_release_generic_tr, | |
6568 | }; | |
6569 | ||
5079f326 | 6570 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
6571 | .open = tracing_clock_open, |
6572 | .read = seq_read, | |
6573 | .llseek = seq_lseek, | |
7b85af63 | 6574 | .release = tracing_single_release_tr, |
5079f326 Z |
6575 | .write = tracing_clock_write, |
6576 | }; | |
6577 | ||
debdd57f HT |
6578 | #ifdef CONFIG_TRACER_SNAPSHOT |
6579 | static const struct file_operations snapshot_fops = { | |
6580 | .open = tracing_snapshot_open, | |
6581 | .read = seq_read, | |
6582 | .write = tracing_snapshot_write, | |
098c879e | 6583 | .llseek = tracing_lseek, |
2b6080f2 | 6584 | .release = tracing_snapshot_release, |
debdd57f | 6585 | }; |
debdd57f | 6586 | |
6de58e62 SRRH |
6587 | static const struct file_operations snapshot_raw_fops = { |
6588 | .open = snapshot_raw_open, | |
6589 | .read = tracing_buffers_read, | |
6590 | .release = tracing_buffers_release, | |
6591 | .splice_read = tracing_buffers_splice_read, | |
6592 | .llseek = no_llseek, | |
2cadf913 SR |
6593 | }; |
6594 | ||
6de58e62 SRRH |
6595 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
6596 | ||
2cadf913 SR |
6597 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
6598 | { | |
46ef2be0 | 6599 | struct trace_array *tr = inode->i_private; |
2cadf913 | 6600 | struct ftrace_buffer_info *info; |
7b85af63 | 6601 | int ret; |
2cadf913 SR |
6602 | |
6603 | if (tracing_disabled) | |
6604 | return -ENODEV; | |
6605 | ||
7b85af63 SRRH |
6606 | if (trace_array_get(tr) < 0) |
6607 | return -ENODEV; | |
6608 | ||
2cadf913 | 6609 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
6610 | if (!info) { |
6611 | trace_array_put(tr); | |
2cadf913 | 6612 | return -ENOMEM; |
7b85af63 | 6613 | } |
2cadf913 | 6614 | |
a695cb58 SRRH |
6615 | mutex_lock(&trace_types_lock); |
6616 | ||
cc60cdc9 | 6617 | info->iter.tr = tr; |
46ef2be0 | 6618 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 6619 | info->iter.trace = tr->current_trace; |
12883efb | 6620 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 6621 | info->spare = NULL; |
2cadf913 | 6622 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 6623 | info->read = (unsigned int)-1; |
2cadf913 SR |
6624 | |
6625 | filp->private_data = info; | |
6626 | ||
cf6ab6d9 SRRH |
6627 | tr->current_trace->ref++; |
6628 | ||
a695cb58 SRRH |
6629 | mutex_unlock(&trace_types_lock); |
6630 | ||
7b85af63 SRRH |
6631 | ret = nonseekable_open(inode, filp); |
6632 | if (ret < 0) | |
6633 | trace_array_put(tr); | |
6634 | ||
6635 | return ret; | |
2cadf913 SR |
6636 | } |
6637 | ||
cc60cdc9 SR |
6638 | static unsigned int |
6639 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
6640 | { | |
6641 | struct ftrace_buffer_info *info = filp->private_data; | |
6642 | struct trace_iterator *iter = &info->iter; | |
6643 | ||
6644 | return trace_poll(iter, filp, poll_table); | |
6645 | } | |
6646 | ||
2cadf913 SR |
6647 | static ssize_t |
6648 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
6649 | size_t count, loff_t *ppos) | |
6650 | { | |
6651 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 6652 | struct trace_iterator *iter = &info->iter; |
a7e52ad7 | 6653 | ssize_t ret = 0; |
6de58e62 | 6654 | ssize_t size; |
2cadf913 | 6655 | |
2dc5d12b SR |
6656 | if (!count) |
6657 | return 0; | |
6658 | ||
6de58e62 | 6659 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
6660 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
6661 | return -EBUSY; | |
6de58e62 SRRH |
6662 | #endif |
6663 | ||
73a757e6 | 6664 | if (!info->spare) { |
12883efb SRRH |
6665 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
6666 | iter->cpu_file); | |
a7e52ad7 SRV |
6667 | if (IS_ERR(info->spare)) { |
6668 | ret = PTR_ERR(info->spare); | |
6669 | info->spare = NULL; | |
6670 | } else { | |
6671 | info->spare_cpu = iter->cpu_file; | |
6672 | } | |
73a757e6 | 6673 | } |
ddd538f3 | 6674 | if (!info->spare) |
a7e52ad7 | 6675 | return ret; |
ddd538f3 | 6676 | |
2cadf913 SR |
6677 | /* Do we have previous read data to read? */ |
6678 | if (info->read < PAGE_SIZE) | |
6679 | goto read; | |
6680 | ||
b627344f | 6681 | again: |
cc60cdc9 | 6682 | trace_access_lock(iter->cpu_file); |
12883efb | 6683 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
6684 | &info->spare, |
6685 | count, | |
cc60cdc9 SR |
6686 | iter->cpu_file, 0); |
6687 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 6688 | |
b627344f SR |
6689 | if (ret < 0) { |
6690 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
6691 | if ((filp->f_flags & O_NONBLOCK)) |
6692 | return -EAGAIN; | |
6693 | ||
e30f53aa | 6694 | ret = wait_on_pipe(iter, false); |
d716ff71 SRRH |
6695 | if (ret) |
6696 | return ret; | |
6697 | ||
b627344f SR |
6698 | goto again; |
6699 | } | |
d716ff71 | 6700 | return 0; |
b627344f | 6701 | } |
436fc280 | 6702 | |
436fc280 | 6703 | info->read = 0; |
b627344f | 6704 | read: |
2cadf913 SR |
6705 | size = PAGE_SIZE - info->read; |
6706 | if (size > count) | |
6707 | size = count; | |
6708 | ||
6709 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
6710 | if (ret == size) |
6711 | return -EFAULT; | |
6712 | ||
2dc5d12b SR |
6713 | size -= ret; |
6714 | ||
2cadf913 SR |
6715 | *ppos += size; |
6716 | info->read += size; | |
6717 | ||
6718 | return size; | |
6719 | } | |
6720 | ||
6721 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
6722 | { | |
6723 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 6724 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 6725 | |
a695cb58 SRRH |
6726 | mutex_lock(&trace_types_lock); |
6727 | ||
cf6ab6d9 SRRH |
6728 | iter->tr->current_trace->ref--; |
6729 | ||
ff451961 | 6730 | __trace_array_put(iter->tr); |
2cadf913 | 6731 | |
ddd538f3 | 6732 | if (info->spare) |
73a757e6 SRV |
6733 | ring_buffer_free_read_page(iter->trace_buffer->buffer, |
6734 | info->spare_cpu, info->spare); | |
2cadf913 SR |
6735 | kfree(info); |
6736 | ||
a695cb58 SRRH |
6737 | mutex_unlock(&trace_types_lock); |
6738 | ||
2cadf913 SR |
6739 | return 0; |
6740 | } | |
6741 | ||
6742 | struct buffer_ref { | |
6743 | struct ring_buffer *buffer; | |
6744 | void *page; | |
73a757e6 | 6745 | int cpu; |
aec0d4aa | 6746 | refcount_t refcount; |
2cadf913 SR |
6747 | }; |
6748 | ||
aec0d4aa JH |
6749 | static void buffer_ref_release(struct buffer_ref *ref) |
6750 | { | |
6751 | if (!refcount_dec_and_test(&ref->refcount)) | |
6752 | return; | |
6753 | ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page); | |
6754 | kfree(ref); | |
6755 | } | |
6756 | ||
2cadf913 SR |
6757 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, |
6758 | struct pipe_buffer *buf) | |
6759 | { | |
6760 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
6761 | ||
aec0d4aa | 6762 | buffer_ref_release(ref); |
2cadf913 SR |
6763 | buf->private = 0; |
6764 | } | |
6765 | ||
c88a0aa7 | 6766 | static bool buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
2cadf913 SR |
6767 | struct pipe_buffer *buf) |
6768 | { | |
6769 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
6770 | ||
c88a0aa7 MW |
6771 | if (refcount_read(&ref->refcount) > INT_MAX/2) |
6772 | return false; | |
6773 | ||
aec0d4aa | 6774 | refcount_inc(&ref->refcount); |
c88a0aa7 | 6775 | return true; |
2cadf913 SR |
6776 | } |
6777 | ||
6778 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 6779 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 6780 | .can_merge = 0, |
2cadf913 SR |
6781 | .confirm = generic_pipe_buf_confirm, |
6782 | .release = buffer_pipe_buf_release, | |
aec0d4aa | 6783 | .steal = generic_pipe_buf_nosteal, |
2cadf913 SR |
6784 | .get = buffer_pipe_buf_get, |
6785 | }; | |
6786 | ||
6787 | /* | |
6788 | * Callback from splice_to_pipe(), if we need to release some pages | |
6789 | * at the end of the spd in case we error'ed out in filling the pipe. | |
6790 | */ | |
6791 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
6792 | { | |
6793 | struct buffer_ref *ref = | |
6794 | (struct buffer_ref *)spd->partial[i].private; | |
6795 | ||
aec0d4aa | 6796 | buffer_ref_release(ref); |
2cadf913 SR |
6797 | spd->partial[i].private = 0; |
6798 | } | |
6799 | ||
6800 | static ssize_t | |
6801 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
6802 | struct pipe_inode_info *pipe, size_t len, | |
6803 | unsigned int flags) | |
6804 | { | |
6805 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 6806 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
6807 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
6808 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 6809 | struct splice_pipe_desc spd = { |
35f3d14d JA |
6810 | .pages = pages_def, |
6811 | .partial = partial_def, | |
047fe360 | 6812 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
6813 | .ops = &buffer_pipe_buf_ops, |
6814 | .spd_release = buffer_spd_release, | |
6815 | }; | |
6816 | struct buffer_ref *ref; | |
234bc126 | 6817 | int entries, i; |
07906da7 | 6818 | ssize_t ret = 0; |
2cadf913 | 6819 | |
6de58e62 | 6820 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
6821 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
6822 | return -EBUSY; | |
6de58e62 SRRH |
6823 | #endif |
6824 | ||
d716ff71 SRRH |
6825 | if (*ppos & (PAGE_SIZE - 1)) |
6826 | return -EINVAL; | |
93cfb3c9 LJ |
6827 | |
6828 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
6829 | if (len < PAGE_SIZE) |
6830 | return -EINVAL; | |
93cfb3c9 LJ |
6831 | len &= PAGE_MASK; |
6832 | } | |
6833 | ||
1ae2293d AV |
6834 | if (splice_grow_spd(pipe, &spd)) |
6835 | return -ENOMEM; | |
6836 | ||
cc60cdc9 SR |
6837 | again: |
6838 | trace_access_lock(iter->cpu_file); | |
12883efb | 6839 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 6840 | |
a786c06d | 6841 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
6842 | struct page *page; |
6843 | int r; | |
6844 | ||
6845 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
6846 | if (!ref) { |
6847 | ret = -ENOMEM; | |
2cadf913 | 6848 | break; |
07906da7 | 6849 | } |
2cadf913 | 6850 | |
aec0d4aa | 6851 | refcount_set(&ref->refcount, 1); |
12883efb | 6852 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 6853 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
a7e52ad7 SRV |
6854 | if (IS_ERR(ref->page)) { |
6855 | ret = PTR_ERR(ref->page); | |
6856 | ref->page = NULL; | |
2cadf913 SR |
6857 | kfree(ref); |
6858 | break; | |
6859 | } | |
73a757e6 | 6860 | ref->cpu = iter->cpu_file; |
2cadf913 SR |
6861 | |
6862 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 6863 | len, iter->cpu_file, 1); |
2cadf913 | 6864 | if (r < 0) { |
73a757e6 SRV |
6865 | ring_buffer_free_read_page(ref->buffer, ref->cpu, |
6866 | ref->page); | |
2cadf913 SR |
6867 | kfree(ref); |
6868 | break; | |
6869 | } | |
6870 | ||
2cadf913 SR |
6871 | page = virt_to_page(ref->page); |
6872 | ||
6873 | spd.pages[i] = page; | |
6874 | spd.partial[i].len = PAGE_SIZE; | |
6875 | spd.partial[i].offset = 0; | |
6876 | spd.partial[i].private = (unsigned long)ref; | |
6877 | spd.nr_pages++; | |
93cfb3c9 | 6878 | *ppos += PAGE_SIZE; |
93459c6c | 6879 | |
12883efb | 6880 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
6881 | } |
6882 | ||
cc60cdc9 | 6883 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
6884 | spd.nr_pages = i; |
6885 | ||
6886 | /* did we read anything? */ | |
6887 | if (!spd.nr_pages) { | |
07906da7 | 6888 | if (ret) |
1ae2293d | 6889 | goto out; |
d716ff71 | 6890 | |
1ae2293d | 6891 | ret = -EAGAIN; |
d716ff71 | 6892 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) |
1ae2293d | 6893 | goto out; |
07906da7 | 6894 | |
e30f53aa | 6895 | ret = wait_on_pipe(iter, true); |
8b8b3683 | 6896 | if (ret) |
1ae2293d | 6897 | goto out; |
e30f53aa | 6898 | |
cc60cdc9 | 6899 | goto again; |
2cadf913 SR |
6900 | } |
6901 | ||
6902 | ret = splice_to_pipe(pipe, &spd); | |
1ae2293d | 6903 | out: |
047fe360 | 6904 | splice_shrink_spd(&spd); |
6de58e62 | 6905 | |
2cadf913 SR |
6906 | return ret; |
6907 | } | |
6908 | ||
6909 | static const struct file_operations tracing_buffers_fops = { | |
6910 | .open = tracing_buffers_open, | |
6911 | .read = tracing_buffers_read, | |
cc60cdc9 | 6912 | .poll = tracing_buffers_poll, |
2cadf913 SR |
6913 | .release = tracing_buffers_release, |
6914 | .splice_read = tracing_buffers_splice_read, | |
6915 | .llseek = no_llseek, | |
6916 | }; | |
6917 | ||
c8d77183 SR |
6918 | static ssize_t |
6919 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
6920 | size_t count, loff_t *ppos) | |
6921 | { | |
4d3435b8 ON |
6922 | struct inode *inode = file_inode(filp); |
6923 | struct trace_array *tr = inode->i_private; | |
12883efb | 6924 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 6925 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
6926 | struct trace_seq *s; |
6927 | unsigned long cnt; | |
c64e148a VN |
6928 | unsigned long long t; |
6929 | unsigned long usec_rem; | |
c8d77183 | 6930 | |
e4f2d10f | 6931 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 6932 | if (!s) |
a646365c | 6933 | return -ENOMEM; |
c8d77183 SR |
6934 | |
6935 | trace_seq_init(s); | |
6936 | ||
12883efb | 6937 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
6938 | trace_seq_printf(s, "entries: %ld\n", cnt); |
6939 | ||
12883efb | 6940 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
6941 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
6942 | ||
12883efb | 6943 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
6944 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
6945 | ||
12883efb | 6946 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
6947 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
6948 | ||
58e8eedf | 6949 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 6950 | /* local or global for trace_clock */ |
12883efb | 6951 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
6952 | usec_rem = do_div(t, USEC_PER_SEC); |
6953 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
6954 | t, usec_rem); | |
6955 | ||
12883efb | 6956 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
6957 | usec_rem = do_div(t, USEC_PER_SEC); |
6958 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
6959 | } else { | |
6960 | /* counter or tsc mode for trace_clock */ | |
6961 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 6962 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 6963 | |
11043d8b | 6964 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 6965 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 6966 | } |
c64e148a | 6967 | |
12883efb | 6968 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
6969 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
6970 | ||
12883efb | 6971 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
6972 | trace_seq_printf(s, "read events: %ld\n", cnt); |
6973 | ||
5ac48378 SRRH |
6974 | count = simple_read_from_buffer(ubuf, count, ppos, |
6975 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
6976 | |
6977 | kfree(s); | |
6978 | ||
6979 | return count; | |
6980 | } | |
6981 | ||
6982 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 6983 | .open = tracing_open_generic_tr, |
c8d77183 | 6984 | .read = tracing_stats_read, |
b444786f | 6985 | .llseek = generic_file_llseek, |
4d3435b8 | 6986 | .release = tracing_release_generic_tr, |
c8d77183 SR |
6987 | }; |
6988 | ||
bc0c38d1 SR |
6989 | #ifdef CONFIG_DYNAMIC_FTRACE |
6990 | ||
6991 | static ssize_t | |
b807c3d0 | 6992 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
6993 | size_t cnt, loff_t *ppos) |
6994 | { | |
6995 | unsigned long *p = filp->private_data; | |
6a9c981b | 6996 | char buf[64]; /* Not too big for a shallow stack */ |
bc0c38d1 SR |
6997 | int r; |
6998 | ||
6a9c981b | 6999 | r = scnprintf(buf, 63, "%ld", *p); |
b807c3d0 SR |
7000 | buf[r++] = '\n'; |
7001 | ||
6a9c981b | 7002 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
7003 | } |
7004 | ||
5e2336a0 | 7005 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 7006 | .open = tracing_open_generic, |
b807c3d0 | 7007 | .read = tracing_read_dyn_info, |
b444786f | 7008 | .llseek = generic_file_llseek, |
bc0c38d1 | 7009 | }; |
77fd5c15 | 7010 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 7011 | |
77fd5c15 SRRH |
7012 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
7013 | static void | |
bca6c8d0 | 7014 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 7015 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 7016 | void *data) |
77fd5c15 | 7017 | { |
cab50379 | 7018 | tracing_snapshot_instance(tr); |
77fd5c15 | 7019 | } |
bc0c38d1 | 7020 | |
77fd5c15 | 7021 | static void |
bca6c8d0 | 7022 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 7023 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 7024 | void *data) |
bc0c38d1 | 7025 | { |
6e444319 | 7026 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 7027 | long *count = NULL; |
77fd5c15 | 7028 | |
1a93f8bd SRV |
7029 | if (mapper) |
7030 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
7031 | ||
7032 | if (count) { | |
7033 | ||
7034 | if (*count <= 0) | |
7035 | return; | |
bc0c38d1 | 7036 | |
77fd5c15 | 7037 | (*count)--; |
1a93f8bd | 7038 | } |
77fd5c15 | 7039 | |
cab50379 | 7040 | tracing_snapshot_instance(tr); |
77fd5c15 SRRH |
7041 | } |
7042 | ||
7043 | static int | |
7044 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
7045 | struct ftrace_probe_ops *ops, void *data) | |
7046 | { | |
6e444319 | 7047 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 7048 | long *count = NULL; |
77fd5c15 SRRH |
7049 | |
7050 | seq_printf(m, "%ps:", (void *)ip); | |
7051 | ||
fa6f0cc7 | 7052 | seq_puts(m, "snapshot"); |
77fd5c15 | 7053 | |
1a93f8bd SRV |
7054 | if (mapper) |
7055 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
7056 | ||
7057 | if (count) | |
7058 | seq_printf(m, ":count=%ld\n", *count); | |
77fd5c15 | 7059 | else |
1a93f8bd | 7060 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
7061 | |
7062 | return 0; | |
7063 | } | |
7064 | ||
1a93f8bd | 7065 | static int |
b5f081b5 | 7066 | ftrace_snapshot_init(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 7067 | unsigned long ip, void *init_data, void **data) |
1a93f8bd | 7068 | { |
6e444319 SRV |
7069 | struct ftrace_func_mapper *mapper = *data; |
7070 | ||
7071 | if (!mapper) { | |
7072 | mapper = allocate_ftrace_func_mapper(); | |
7073 | if (!mapper) | |
7074 | return -ENOMEM; | |
7075 | *data = mapper; | |
7076 | } | |
1a93f8bd | 7077 | |
6e444319 | 7078 | return ftrace_func_mapper_add_ip(mapper, ip, init_data); |
1a93f8bd SRV |
7079 | } |
7080 | ||
7081 | static void | |
b5f081b5 | 7082 | ftrace_snapshot_free(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 7083 | unsigned long ip, void *data) |
1a93f8bd | 7084 | { |
6e444319 SRV |
7085 | struct ftrace_func_mapper *mapper = data; |
7086 | ||
7087 | if (!ip) { | |
7088 | if (!mapper) | |
7089 | return; | |
7090 | free_ftrace_func_mapper(mapper, NULL); | |
7091 | return; | |
7092 | } | |
1a93f8bd SRV |
7093 | |
7094 | ftrace_func_mapper_remove_ip(mapper, ip); | |
7095 | } | |
7096 | ||
77fd5c15 SRRH |
7097 | static struct ftrace_probe_ops snapshot_probe_ops = { |
7098 | .func = ftrace_snapshot, | |
7099 | .print = ftrace_snapshot_print, | |
7100 | }; | |
7101 | ||
7102 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
7103 | .func = ftrace_count_snapshot, | |
7104 | .print = ftrace_snapshot_print, | |
1a93f8bd SRV |
7105 | .init = ftrace_snapshot_init, |
7106 | .free = ftrace_snapshot_free, | |
77fd5c15 SRRH |
7107 | }; |
7108 | ||
7109 | static int | |
04ec7bb6 | 7110 | ftrace_trace_snapshot_callback(struct trace_array *tr, struct ftrace_hash *hash, |
77fd5c15 SRRH |
7111 | char *glob, char *cmd, char *param, int enable) |
7112 | { | |
7113 | struct ftrace_probe_ops *ops; | |
7114 | void *count = (void *)-1; | |
7115 | char *number; | |
7116 | int ret; | |
7117 | ||
0f179765 SRV |
7118 | if (!tr) |
7119 | return -ENODEV; | |
7120 | ||
77fd5c15 SRRH |
7121 | /* hash funcs only work with set_ftrace_filter */ |
7122 | if (!enable) | |
7123 | return -EINVAL; | |
7124 | ||
7125 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
7126 | ||
d3d532d7 | 7127 | if (glob[0] == '!') |
7b60f3d8 | 7128 | return unregister_ftrace_function_probe_func(glob+1, tr, ops); |
77fd5c15 SRRH |
7129 | |
7130 | if (!param) | |
7131 | goto out_reg; | |
7132 | ||
7133 | number = strsep(¶m, ":"); | |
7134 | ||
7135 | if (!strlen(number)) | |
7136 | goto out_reg; | |
7137 | ||
7138 | /* | |
7139 | * We use the callback data field (which is a pointer) | |
7140 | * as our counter. | |
7141 | */ | |
7142 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
7143 | if (ret) | |
7144 | return ret; | |
7145 | ||
7146 | out_reg: | |
c6a95f37 | 7147 | ret = tracing_alloc_snapshot_instance(tr); |
df62db5b SRV |
7148 | if (ret < 0) |
7149 | goto out; | |
77fd5c15 | 7150 | |
4c174688 | 7151 | ret = register_ftrace_function_probe(glob, tr, ops, count); |
77fd5c15 | 7152 | |
df62db5b | 7153 | out: |
77fd5c15 SRRH |
7154 | return ret < 0 ? ret : 0; |
7155 | } | |
7156 | ||
7157 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
7158 | .name = "snapshot", | |
7159 | .func = ftrace_trace_snapshot_callback, | |
7160 | }; | |
7161 | ||
38de93ab | 7162 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
7163 | { |
7164 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
7165 | } | |
7166 | #else | |
38de93ab | 7167 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 7168 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 7169 | |
7eeafbca | 7170 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 7171 | { |
8434dc93 SRRH |
7172 | if (WARN_ON(!tr->dir)) |
7173 | return ERR_PTR(-ENODEV); | |
7174 | ||
7175 | /* Top directory uses NULL as the parent */ | |
7176 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
7177 | return NULL; | |
7178 | ||
7179 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 7180 | return tr->dir; |
bc0c38d1 SR |
7181 | } |
7182 | ||
2b6080f2 | 7183 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 7184 | { |
b04cc6b1 FW |
7185 | struct dentry *d_tracer; |
7186 | ||
2b6080f2 SR |
7187 | if (tr->percpu_dir) |
7188 | return tr->percpu_dir; | |
b04cc6b1 | 7189 | |
7eeafbca | 7190 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 7191 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
7192 | return NULL; |
7193 | ||
8434dc93 | 7194 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 7195 | |
2b6080f2 | 7196 | WARN_ONCE(!tr->percpu_dir, |
8434dc93 | 7197 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 7198 | |
2b6080f2 | 7199 | return tr->percpu_dir; |
b04cc6b1 FW |
7200 | } |
7201 | ||
649e9c70 ON |
7202 | static struct dentry * |
7203 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
7204 | void *data, long cpu, const struct file_operations *fops) | |
7205 | { | |
7206 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
7207 | ||
7208 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 7209 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
7210 | return ret; |
7211 | } | |
7212 | ||
2b6080f2 | 7213 | static void |
8434dc93 | 7214 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 7215 | { |
2b6080f2 | 7216 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 7217 | struct dentry *d_cpu; |
dd49a38c | 7218 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 7219 | |
0a3d7ce7 NK |
7220 | if (!d_percpu) |
7221 | return; | |
7222 | ||
dd49a38c | 7223 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 7224 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 7225 | if (!d_cpu) { |
a395d6a7 | 7226 | pr_warn("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
7227 | return; |
7228 | } | |
b04cc6b1 | 7229 | |
8656e7a2 | 7230 | /* per cpu trace_pipe */ |
649e9c70 | 7231 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 7232 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
7233 | |
7234 | /* per cpu trace */ | |
649e9c70 | 7235 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 7236 | tr, cpu, &tracing_fops); |
7f96f93f | 7237 | |
649e9c70 | 7238 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 7239 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 7240 | |
649e9c70 | 7241 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 7242 | tr, cpu, &tracing_stats_fops); |
438ced17 | 7243 | |
649e9c70 | 7244 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 7245 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
7246 | |
7247 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 7248 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 7249 | tr, cpu, &snapshot_fops); |
6de58e62 | 7250 | |
649e9c70 | 7251 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 7252 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 7253 | #endif |
b04cc6b1 FW |
7254 | } |
7255 | ||
60a11774 SR |
7256 | #ifdef CONFIG_FTRACE_SELFTEST |
7257 | /* Let selftest have access to static functions in this file */ | |
7258 | #include "trace_selftest.c" | |
7259 | #endif | |
7260 | ||
577b785f SR |
7261 | static ssize_t |
7262 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
7263 | loff_t *ppos) | |
7264 | { | |
7265 | struct trace_option_dentry *topt = filp->private_data; | |
7266 | char *buf; | |
7267 | ||
7268 | if (topt->flags->val & topt->opt->bit) | |
7269 | buf = "1\n"; | |
7270 | else | |
7271 | buf = "0\n"; | |
7272 | ||
7273 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
7274 | } | |
7275 | ||
7276 | static ssize_t | |
7277 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
7278 | loff_t *ppos) | |
7279 | { | |
7280 | struct trace_option_dentry *topt = filp->private_data; | |
7281 | unsigned long val; | |
577b785f SR |
7282 | int ret; |
7283 | ||
22fe9b54 PH |
7284 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
7285 | if (ret) | |
577b785f SR |
7286 | return ret; |
7287 | ||
8d18eaaf LZ |
7288 | if (val != 0 && val != 1) |
7289 | return -EINVAL; | |
577b785f | 7290 | |
8d18eaaf | 7291 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 7292 | mutex_lock(&trace_types_lock); |
8c1a49ae | 7293 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 7294 | topt->opt, !val); |
577b785f SR |
7295 | mutex_unlock(&trace_types_lock); |
7296 | if (ret) | |
7297 | return ret; | |
577b785f SR |
7298 | } |
7299 | ||
7300 | *ppos += cnt; | |
7301 | ||
7302 | return cnt; | |
7303 | } | |
7304 | ||
7305 | ||
7306 | static const struct file_operations trace_options_fops = { | |
7307 | .open = tracing_open_generic, | |
7308 | .read = trace_options_read, | |
7309 | .write = trace_options_write, | |
b444786f | 7310 | .llseek = generic_file_llseek, |
577b785f SR |
7311 | }; |
7312 | ||
9a38a885 SRRH |
7313 | /* |
7314 | * In order to pass in both the trace_array descriptor as well as the index | |
7315 | * to the flag that the trace option file represents, the trace_array | |
7316 | * has a character array of trace_flags_index[], which holds the index | |
7317 | * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. | |
7318 | * The address of this character array is passed to the flag option file | |
7319 | * read/write callbacks. | |
7320 | * | |
7321 | * In order to extract both the index and the trace_array descriptor, | |
7322 | * get_tr_index() uses the following algorithm. | |
7323 | * | |
7324 | * idx = *ptr; | |
7325 | * | |
7326 | * As the pointer itself contains the address of the index (remember | |
7327 | * index[1] == 1). | |
7328 | * | |
7329 | * Then to get the trace_array descriptor, by subtracting that index | |
7330 | * from the ptr, we get to the start of the index itself. | |
7331 | * | |
7332 | * ptr - idx == &index[0] | |
7333 | * | |
7334 | * Then a simple container_of() from that pointer gets us to the | |
7335 | * trace_array descriptor. | |
7336 | */ | |
7337 | static void get_tr_index(void *data, struct trace_array **ptr, | |
7338 | unsigned int *pindex) | |
7339 | { | |
7340 | *pindex = *(unsigned char *)data; | |
7341 | ||
7342 | *ptr = container_of(data - *pindex, struct trace_array, | |
7343 | trace_flags_index); | |
7344 | } | |
7345 | ||
a8259075 SR |
7346 | static ssize_t |
7347 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
7348 | loff_t *ppos) | |
7349 | { | |
9a38a885 SRRH |
7350 | void *tr_index = filp->private_data; |
7351 | struct trace_array *tr; | |
7352 | unsigned int index; | |
a8259075 SR |
7353 | char *buf; |
7354 | ||
9a38a885 SRRH |
7355 | get_tr_index(tr_index, &tr, &index); |
7356 | ||
7357 | if (tr->trace_flags & (1 << index)) | |
a8259075 SR |
7358 | buf = "1\n"; |
7359 | else | |
7360 | buf = "0\n"; | |
7361 | ||
7362 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
7363 | } | |
7364 | ||
7365 | static ssize_t | |
7366 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
7367 | loff_t *ppos) | |
7368 | { | |
9a38a885 SRRH |
7369 | void *tr_index = filp->private_data; |
7370 | struct trace_array *tr; | |
7371 | unsigned int index; | |
a8259075 SR |
7372 | unsigned long val; |
7373 | int ret; | |
7374 | ||
9a38a885 SRRH |
7375 | get_tr_index(tr_index, &tr, &index); |
7376 | ||
22fe9b54 PH |
7377 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
7378 | if (ret) | |
a8259075 SR |
7379 | return ret; |
7380 | ||
f2d84b65 | 7381 | if (val != 0 && val != 1) |
a8259075 | 7382 | return -EINVAL; |
69d34da2 | 7383 | |
af247192 | 7384 | mutex_lock(&event_mutex); |
69d34da2 | 7385 | mutex_lock(&trace_types_lock); |
2b6080f2 | 7386 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 7387 | mutex_unlock(&trace_types_lock); |
af247192 | 7388 | mutex_unlock(&event_mutex); |
a8259075 | 7389 | |
613f04a0 SRRH |
7390 | if (ret < 0) |
7391 | return ret; | |
7392 | ||
a8259075 SR |
7393 | *ppos += cnt; |
7394 | ||
7395 | return cnt; | |
7396 | } | |
7397 | ||
a8259075 SR |
7398 | static const struct file_operations trace_options_core_fops = { |
7399 | .open = tracing_open_generic, | |
7400 | .read = trace_options_core_read, | |
7401 | .write = trace_options_core_write, | |
b444786f | 7402 | .llseek = generic_file_llseek, |
a8259075 SR |
7403 | }; |
7404 | ||
5452af66 | 7405 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 7406 | umode_t mode, |
5452af66 FW |
7407 | struct dentry *parent, |
7408 | void *data, | |
7409 | const struct file_operations *fops) | |
7410 | { | |
7411 | struct dentry *ret; | |
7412 | ||
8434dc93 | 7413 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 7414 | if (!ret) |
a395d6a7 | 7415 | pr_warn("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
7416 | |
7417 | return ret; | |
7418 | } | |
7419 | ||
7420 | ||
2b6080f2 | 7421 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
7422 | { |
7423 | struct dentry *d_tracer; | |
a8259075 | 7424 | |
2b6080f2 SR |
7425 | if (tr->options) |
7426 | return tr->options; | |
a8259075 | 7427 | |
7eeafbca | 7428 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 7429 | if (IS_ERR(d_tracer)) |
a8259075 SR |
7430 | return NULL; |
7431 | ||
8434dc93 | 7432 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 7433 | if (!tr->options) { |
a395d6a7 | 7434 | pr_warn("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
7435 | return NULL; |
7436 | } | |
7437 | ||
2b6080f2 | 7438 | return tr->options; |
a8259075 SR |
7439 | } |
7440 | ||
577b785f | 7441 | static void |
2b6080f2 SR |
7442 | create_trace_option_file(struct trace_array *tr, |
7443 | struct trace_option_dentry *topt, | |
577b785f SR |
7444 | struct tracer_flags *flags, |
7445 | struct tracer_opt *opt) | |
7446 | { | |
7447 | struct dentry *t_options; | |
577b785f | 7448 | |
2b6080f2 | 7449 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
7450 | if (!t_options) |
7451 | return; | |
7452 | ||
7453 | topt->flags = flags; | |
7454 | topt->opt = opt; | |
2b6080f2 | 7455 | topt->tr = tr; |
577b785f | 7456 | |
5452af66 | 7457 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
7458 | &trace_options_fops); |
7459 | ||
577b785f SR |
7460 | } |
7461 | ||
37aea98b | 7462 | static void |
2b6080f2 | 7463 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
7464 | { |
7465 | struct trace_option_dentry *topts; | |
37aea98b | 7466 | struct trace_options *tr_topts; |
577b785f SR |
7467 | struct tracer_flags *flags; |
7468 | struct tracer_opt *opts; | |
7469 | int cnt; | |
37aea98b | 7470 | int i; |
577b785f SR |
7471 | |
7472 | if (!tracer) | |
37aea98b | 7473 | return; |
577b785f SR |
7474 | |
7475 | flags = tracer->flags; | |
7476 | ||
7477 | if (!flags || !flags->opts) | |
37aea98b SRRH |
7478 | return; |
7479 | ||
7480 | /* | |
7481 | * If this is an instance, only create flags for tracers | |
7482 | * the instance may have. | |
7483 | */ | |
7484 | if (!trace_ok_for_array(tracer, tr)) | |
7485 | return; | |
7486 | ||
7487 | for (i = 0; i < tr->nr_topts; i++) { | |
d39cdd20 CH |
7488 | /* Make sure there's no duplicate flags. */ |
7489 | if (WARN_ON_ONCE(tr->topts[i].tracer->flags == tracer->flags)) | |
37aea98b SRRH |
7490 | return; |
7491 | } | |
577b785f SR |
7492 | |
7493 | opts = flags->opts; | |
7494 | ||
7495 | for (cnt = 0; opts[cnt].name; cnt++) | |
7496 | ; | |
7497 | ||
0cfe8245 | 7498 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f | 7499 | if (!topts) |
37aea98b SRRH |
7500 | return; |
7501 | ||
7502 | tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), | |
7503 | GFP_KERNEL); | |
7504 | if (!tr_topts) { | |
7505 | kfree(topts); | |
7506 | return; | |
7507 | } | |
7508 | ||
7509 | tr->topts = tr_topts; | |
7510 | tr->topts[tr->nr_topts].tracer = tracer; | |
7511 | tr->topts[tr->nr_topts].topts = topts; | |
7512 | tr->nr_topts++; | |
577b785f | 7513 | |
41d9c0be | 7514 | for (cnt = 0; opts[cnt].name; cnt++) { |
2b6080f2 | 7515 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f | 7516 | &opts[cnt]); |
41d9c0be SRRH |
7517 | WARN_ONCE(topts[cnt].entry == NULL, |
7518 | "Failed to create trace option: %s", | |
7519 | opts[cnt].name); | |
7520 | } | |
577b785f SR |
7521 | } |
7522 | ||
a8259075 | 7523 | static struct dentry * |
2b6080f2 SR |
7524 | create_trace_option_core_file(struct trace_array *tr, |
7525 | const char *option, long index) | |
a8259075 SR |
7526 | { |
7527 | struct dentry *t_options; | |
a8259075 | 7528 | |
2b6080f2 | 7529 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
7530 | if (!t_options) |
7531 | return NULL; | |
7532 | ||
9a38a885 SRRH |
7533 | return trace_create_file(option, 0644, t_options, |
7534 | (void *)&tr->trace_flags_index[index], | |
7535 | &trace_options_core_fops); | |
a8259075 SR |
7536 | } |
7537 | ||
16270145 | 7538 | static void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
7539 | { |
7540 | struct dentry *t_options; | |
16270145 | 7541 | bool top_level = tr == &global_trace; |
a8259075 SR |
7542 | int i; |
7543 | ||
2b6080f2 | 7544 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
7545 | if (!t_options) |
7546 | return; | |
7547 | ||
16270145 SRRH |
7548 | for (i = 0; trace_options[i]; i++) { |
7549 | if (top_level || | |
7550 | !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) | |
7551 | create_trace_option_core_file(tr, trace_options[i], i); | |
7552 | } | |
a8259075 SR |
7553 | } |
7554 | ||
499e5470 SR |
7555 | static ssize_t |
7556 | rb_simple_read(struct file *filp, char __user *ubuf, | |
7557 | size_t cnt, loff_t *ppos) | |
7558 | { | |
348f0fc2 | 7559 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
7560 | char buf[64]; |
7561 | int r; | |
7562 | ||
10246fa3 | 7563 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
7564 | r = sprintf(buf, "%d\n", r); |
7565 | ||
7566 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
7567 | } | |
7568 | ||
7569 | static ssize_t | |
7570 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
7571 | size_t cnt, loff_t *ppos) | |
7572 | { | |
348f0fc2 | 7573 | struct trace_array *tr = filp->private_data; |
12883efb | 7574 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
7575 | unsigned long val; |
7576 | int ret; | |
7577 | ||
7578 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
7579 | if (ret) | |
7580 | return ret; | |
7581 | ||
7582 | if (buffer) { | |
2df8f8a6 | 7583 | mutex_lock(&trace_types_lock); |
4c901675 SRV |
7584 | if (!!val == tracer_tracing_is_on(tr)) { |
7585 | val = 0; /* do nothing */ | |
7586 | } else if (val) { | |
10246fa3 | 7587 | tracer_tracing_on(tr); |
2b6080f2 SR |
7588 | if (tr->current_trace->start) |
7589 | tr->current_trace->start(tr); | |
2df8f8a6 | 7590 | } else { |
10246fa3 | 7591 | tracer_tracing_off(tr); |
2b6080f2 SR |
7592 | if (tr->current_trace->stop) |
7593 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
7594 | } |
7595 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
7596 | } |
7597 | ||
7598 | (*ppos)++; | |
7599 | ||
7600 | return cnt; | |
7601 | } | |
7602 | ||
7603 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 7604 | .open = tracing_open_generic_tr, |
499e5470 SR |
7605 | .read = rb_simple_read, |
7606 | .write = rb_simple_write, | |
7b85af63 | 7607 | .release = tracing_release_generic_tr, |
499e5470 SR |
7608 | .llseek = default_llseek, |
7609 | }; | |
7610 | ||
277ba044 SR |
7611 | struct dentry *trace_instance_dir; |
7612 | ||
7613 | static void | |
8434dc93 | 7614 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 7615 | |
55034cd6 SRRH |
7616 | static int |
7617 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
7618 | { |
7619 | enum ring_buffer_flags rb_flags; | |
737223fb | 7620 | |
983f938a | 7621 | rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
737223fb | 7622 | |
dced341b SRRH |
7623 | buf->tr = tr; |
7624 | ||
55034cd6 SRRH |
7625 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
7626 | if (!buf->buffer) | |
7627 | return -ENOMEM; | |
737223fb | 7628 | |
55034cd6 SRRH |
7629 | buf->data = alloc_percpu(struct trace_array_cpu); |
7630 | if (!buf->data) { | |
7631 | ring_buffer_free(buf->buffer); | |
21a9c734 | 7632 | buf->buffer = NULL; |
55034cd6 SRRH |
7633 | return -ENOMEM; |
7634 | } | |
737223fb | 7635 | |
737223fb SRRH |
7636 | /* Allocate the first page for all buffers */ |
7637 | set_buffer_entries(&tr->trace_buffer, | |
7638 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
7639 | ||
55034cd6 SRRH |
7640 | return 0; |
7641 | } | |
737223fb | 7642 | |
55034cd6 SRRH |
7643 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
7644 | { | |
7645 | int ret; | |
737223fb | 7646 | |
55034cd6 SRRH |
7647 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
7648 | if (ret) | |
7649 | return ret; | |
737223fb | 7650 | |
55034cd6 SRRH |
7651 | #ifdef CONFIG_TRACER_MAX_TRACE |
7652 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
7653 | allocate_snapshot ? size : 1); | |
7654 | if (WARN_ON(ret)) { | |
737223fb | 7655 | ring_buffer_free(tr->trace_buffer.buffer); |
98669825 | 7656 | tr->trace_buffer.buffer = NULL; |
55034cd6 | 7657 | free_percpu(tr->trace_buffer.data); |
98669825 | 7658 | tr->trace_buffer.data = NULL; |
55034cd6 SRRH |
7659 | return -ENOMEM; |
7660 | } | |
7661 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 7662 | |
55034cd6 SRRH |
7663 | /* |
7664 | * Only the top level trace array gets its snapshot allocated | |
7665 | * from the kernel command line. | |
7666 | */ | |
7667 | allocate_snapshot = false; | |
737223fb | 7668 | #endif |
4d9c4f41 SRV |
7669 | |
7670 | /* | |
7671 | * Because of some magic with the way alloc_percpu() works on | |
7672 | * x86_64, we need to synchronize the pgd of all the tables, | |
7673 | * otherwise the trace events that happen in x86_64 page fault | |
7674 | * handlers can't cope with accessing the chance that a | |
7675 | * alloc_percpu()'d memory might be touched in the page fault trace | |
7676 | * event. Oh, and we need to audit all other alloc_percpu() and vmalloc() | |
7677 | * calls in tracing, because something might get triggered within a | |
7678 | * page fault trace event! | |
7679 | */ | |
7680 | vmalloc_sync_mappings(); | |
7681 | ||
55034cd6 | 7682 | return 0; |
737223fb SRRH |
7683 | } |
7684 | ||
f0b70cc4 SRRH |
7685 | static void free_trace_buffer(struct trace_buffer *buf) |
7686 | { | |
7687 | if (buf->buffer) { | |
7688 | ring_buffer_free(buf->buffer); | |
7689 | buf->buffer = NULL; | |
7690 | free_percpu(buf->data); | |
7691 | buf->data = NULL; | |
7692 | } | |
7693 | } | |
7694 | ||
23aaa3c1 SRRH |
7695 | static void free_trace_buffers(struct trace_array *tr) |
7696 | { | |
7697 | if (!tr) | |
7698 | return; | |
7699 | ||
f0b70cc4 | 7700 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
7701 | |
7702 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 7703 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
7704 | #endif |
7705 | } | |
7706 | ||
9a38a885 SRRH |
7707 | static void init_trace_flags_index(struct trace_array *tr) |
7708 | { | |
7709 | int i; | |
7710 | ||
7711 | /* Used by the trace options files */ | |
7712 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) | |
7713 | tr->trace_flags_index[i] = i; | |
7714 | } | |
7715 | ||
37aea98b SRRH |
7716 | static void __update_tracer_options(struct trace_array *tr) |
7717 | { | |
7718 | struct tracer *t; | |
7719 | ||
7720 | for (t = trace_types; t; t = t->next) | |
7721 | add_tracer_options(tr, t); | |
7722 | } | |
7723 | ||
7724 | static void update_tracer_options(struct trace_array *tr) | |
7725 | { | |
7726 | mutex_lock(&trace_types_lock); | |
7727 | __update_tracer_options(tr); | |
7728 | mutex_unlock(&trace_types_lock); | |
7729 | } | |
7730 | ||
eae47358 | 7731 | static int instance_mkdir(const char *name) |
737223fb | 7732 | { |
277ba044 SR |
7733 | struct trace_array *tr; |
7734 | int ret; | |
277ba044 | 7735 | |
dc13f456 | 7736 | mutex_lock(&event_mutex); |
277ba044 SR |
7737 | mutex_lock(&trace_types_lock); |
7738 | ||
7739 | ret = -EEXIST; | |
7740 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
7741 | if (tr->name && strcmp(tr->name, name) == 0) | |
7742 | goto out_unlock; | |
7743 | } | |
7744 | ||
7745 | ret = -ENOMEM; | |
7746 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
7747 | if (!tr) | |
7748 | goto out_unlock; | |
7749 | ||
7750 | tr->name = kstrdup(name, GFP_KERNEL); | |
7751 | if (!tr->name) | |
7752 | goto out_free_tr; | |
7753 | ||
ccfe9e42 AL |
7754 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
7755 | goto out_free_tr; | |
7756 | ||
20550622 | 7757 | tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS; |
983f938a | 7758 | |
ccfe9e42 AL |
7759 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); |
7760 | ||
277ba044 SR |
7761 | raw_spin_lock_init(&tr->start_lock); |
7762 | ||
0b9b12c1 SRRH |
7763 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
7764 | ||
277ba044 SR |
7765 | tr->current_trace = &nop_trace; |
7766 | ||
7767 | INIT_LIST_HEAD(&tr->systems); | |
7768 | INIT_LIST_HEAD(&tr->events); | |
7769 | ||
737223fb | 7770 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
7771 | goto out_free_tr; |
7772 | ||
8434dc93 | 7773 | tr->dir = tracefs_create_dir(name, trace_instance_dir); |
277ba044 SR |
7774 | if (!tr->dir) |
7775 | goto out_free_tr; | |
7776 | ||
7777 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 | 7778 | if (ret) { |
8434dc93 | 7779 | tracefs_remove_recursive(tr->dir); |
277ba044 | 7780 | goto out_free_tr; |
609e85a7 | 7781 | } |
277ba044 | 7782 | |
04ec7bb6 SRV |
7783 | ftrace_init_trace_array(tr); |
7784 | ||
8434dc93 | 7785 | init_tracer_tracefs(tr, tr->dir); |
9a38a885 | 7786 | init_trace_flags_index(tr); |
37aea98b | 7787 | __update_tracer_options(tr); |
277ba044 SR |
7788 | |
7789 | list_add(&tr->list, &ftrace_trace_arrays); | |
7790 | ||
7791 | mutex_unlock(&trace_types_lock); | |
dc13f456 | 7792 | mutex_unlock(&event_mutex); |
277ba044 SR |
7793 | |
7794 | return 0; | |
7795 | ||
7796 | out_free_tr: | |
23aaa3c1 | 7797 | free_trace_buffers(tr); |
ccfe9e42 | 7798 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
7799 | kfree(tr->name); |
7800 | kfree(tr); | |
7801 | ||
7802 | out_unlock: | |
7803 | mutex_unlock(&trace_types_lock); | |
dc13f456 | 7804 | mutex_unlock(&event_mutex); |
277ba044 SR |
7805 | |
7806 | return ret; | |
7807 | ||
7808 | } | |
7809 | ||
eae47358 | 7810 | static int instance_rmdir(const char *name) |
0c8916c3 SR |
7811 | { |
7812 | struct trace_array *tr; | |
7813 | int found = 0; | |
7814 | int ret; | |
37aea98b | 7815 | int i; |
0c8916c3 | 7816 | |
dc13f456 | 7817 | mutex_lock(&event_mutex); |
0c8916c3 SR |
7818 | mutex_lock(&trace_types_lock); |
7819 | ||
7820 | ret = -ENODEV; | |
7821 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
7822 | if (tr->name && strcmp(tr->name, name) == 0) { | |
7823 | found = 1; | |
7824 | break; | |
7825 | } | |
7826 | } | |
7827 | if (!found) | |
7828 | goto out_unlock; | |
7829 | ||
a695cb58 | 7830 | ret = -EBUSY; |
cf6ab6d9 | 7831 | if (tr->ref || (tr->current_trace && tr->current_trace->ref)) |
a695cb58 SRRH |
7832 | goto out_unlock; |
7833 | ||
0c8916c3 SR |
7834 | list_del(&tr->list); |
7835 | ||
20550622 SRRH |
7836 | /* Disable all the flags that were enabled coming in */ |
7837 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) { | |
7838 | if ((1 << i) & ZEROED_TRACE_FLAGS) | |
7839 | set_tracer_flag(tr, 1 << i, 0); | |
7840 | } | |
7841 | ||
6b450d25 | 7842 | tracing_set_nop(tr); |
a0e6369e | 7843 | clear_ftrace_function_probes(tr); |
0c8916c3 | 7844 | event_trace_del_tracer(tr); |
d879d0b8 | 7845 | ftrace_clear_pids(tr); |
591dffda | 7846 | ftrace_destroy_function_files(tr); |
681a4a2f | 7847 | tracefs_remove_recursive(tr->dir); |
a9fcaaac | 7848 | free_trace_buffers(tr); |
0c8916c3 | 7849 | |
37aea98b SRRH |
7850 | for (i = 0; i < tr->nr_topts; i++) { |
7851 | kfree(tr->topts[i].topts); | |
7852 | } | |
7853 | kfree(tr->topts); | |
7854 | ||
db9108e0 | 7855 | free_cpumask_var(tr->tracing_cpumask); |
0c8916c3 SR |
7856 | kfree(tr->name); |
7857 | kfree(tr); | |
7858 | ||
7859 | ret = 0; | |
7860 | ||
7861 | out_unlock: | |
7862 | mutex_unlock(&trace_types_lock); | |
dc13f456 | 7863 | mutex_unlock(&event_mutex); |
0c8916c3 SR |
7864 | |
7865 | return ret; | |
7866 | } | |
7867 | ||
277ba044 SR |
7868 | static __init void create_trace_instances(struct dentry *d_tracer) |
7869 | { | |
eae47358 SRRH |
7870 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
7871 | instance_mkdir, | |
7872 | instance_rmdir); | |
277ba044 SR |
7873 | if (WARN_ON(!trace_instance_dir)) |
7874 | return; | |
277ba044 SR |
7875 | } |
7876 | ||
2b6080f2 | 7877 | static void |
8434dc93 | 7878 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 7879 | { |
121aaee7 | 7880 | int cpu; |
2b6080f2 | 7881 | |
607e2ea1 SRRH |
7882 | trace_create_file("available_tracers", 0444, d_tracer, |
7883 | tr, &show_traces_fops); | |
7884 | ||
7885 | trace_create_file("current_tracer", 0644, d_tracer, | |
7886 | tr, &set_tracer_fops); | |
7887 | ||
ccfe9e42 AL |
7888 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
7889 | tr, &tracing_cpumask_fops); | |
7890 | ||
2b6080f2 SR |
7891 | trace_create_file("trace_options", 0644, d_tracer, |
7892 | tr, &tracing_iter_fops); | |
7893 | ||
7894 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 7895 | tr, &tracing_fops); |
2b6080f2 SR |
7896 | |
7897 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 7898 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
7899 | |
7900 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 7901 | tr, &tracing_entries_fops); |
2b6080f2 SR |
7902 | |
7903 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
7904 | tr, &tracing_total_entries_fops); | |
7905 | ||
238ae93d | 7906 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
7907 | tr, &tracing_free_buffer_fops); |
7908 | ||
7909 | trace_create_file("trace_marker", 0220, d_tracer, | |
7910 | tr, &tracing_mark_fops); | |
7911 | ||
fa32e855 SR |
7912 | trace_create_file("trace_marker_raw", 0220, d_tracer, |
7913 | tr, &tracing_mark_raw_fops); | |
7914 | ||
2b6080f2 SR |
7915 | trace_create_file("trace_clock", 0644, d_tracer, tr, |
7916 | &trace_clock_fops); | |
7917 | ||
7918 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 7919 | tr, &rb_simple_fops); |
ce9bae55 | 7920 | |
16270145 SRRH |
7921 | create_trace_options_dir(tr); |
7922 | ||
f971cc9a | 7923 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
6d9b3fa5 SRRH |
7924 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
7925 | &tr->max_latency, &tracing_max_lat_fops); | |
7926 | #endif | |
7927 | ||
591dffda SRRH |
7928 | if (ftrace_create_function_files(tr, d_tracer)) |
7929 | WARN(1, "Could not allocate function filter files"); | |
7930 | ||
ce9bae55 SRRH |
7931 | #ifdef CONFIG_TRACER_SNAPSHOT |
7932 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 7933 | tr, &snapshot_fops); |
ce9bae55 | 7934 | #endif |
121aaee7 SRRH |
7935 | |
7936 | for_each_tracing_cpu(cpu) | |
8434dc93 | 7937 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 7938 | |
345ddcc8 | 7939 | ftrace_init_tracefs(tr, d_tracer); |
2b6080f2 SR |
7940 | } |
7941 | ||
93faccbb | 7942 | static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore) |
f76180bc SRRH |
7943 | { |
7944 | struct vfsmount *mnt; | |
7945 | struct file_system_type *type; | |
7946 | ||
7947 | /* | |
7948 | * To maintain backward compatibility for tools that mount | |
7949 | * debugfs to get to the tracing facility, tracefs is automatically | |
7950 | * mounted to the debugfs/tracing directory. | |
7951 | */ | |
7952 | type = get_fs_type("tracefs"); | |
7953 | if (!type) | |
7954 | return NULL; | |
93faccbb | 7955 | mnt = vfs_submount(mntpt, type, "tracefs", NULL); |
f76180bc SRRH |
7956 | put_filesystem(type); |
7957 | if (IS_ERR(mnt)) | |
7958 | return NULL; | |
7959 | mntget(mnt); | |
7960 | ||
7961 | return mnt; | |
7962 | } | |
7963 | ||
7eeafbca SRRH |
7964 | /** |
7965 | * tracing_init_dentry - initialize top level trace array | |
7966 | * | |
7967 | * This is called when creating files or directories in the tracing | |
7968 | * directory. It is called via fs_initcall() by any of the boot up code | |
7969 | * and expects to return the dentry of the top level tracing directory. | |
7970 | */ | |
7971 | struct dentry *tracing_init_dentry(void) | |
7972 | { | |
7973 | struct trace_array *tr = &global_trace; | |
7974 | ||
f76180bc | 7975 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 7976 | if (tr->dir) |
f76180bc | 7977 | return NULL; |
7eeafbca | 7978 | |
8b129199 JW |
7979 | if (WARN_ON(!tracefs_initialized()) || |
7980 | (IS_ENABLED(CONFIG_DEBUG_FS) && | |
7981 | WARN_ON(!debugfs_initialized()))) | |
7eeafbca SRRH |
7982 | return ERR_PTR(-ENODEV); |
7983 | ||
f76180bc SRRH |
7984 | /* |
7985 | * As there may still be users that expect the tracing | |
7986 | * files to exist in debugfs/tracing, we must automount | |
7987 | * the tracefs file system there, so older tools still | |
7988 | * work with the newer kerenl. | |
7989 | */ | |
7990 | tr->dir = debugfs_create_automount("tracing", NULL, | |
7991 | trace_automount, NULL); | |
7eeafbca SRRH |
7992 | if (!tr->dir) { |
7993 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
7994 | return ERR_PTR(-ENOMEM); | |
7995 | } | |
7996 | ||
8434dc93 | 7997 | return NULL; |
7eeafbca SRRH |
7998 | } |
7999 | ||
00f4b652 JL |
8000 | extern struct trace_eval_map *__start_ftrace_eval_maps[]; |
8001 | extern struct trace_eval_map *__stop_ftrace_eval_maps[]; | |
0c564a53 | 8002 | |
5f60b351 | 8003 | static void __init trace_eval_init(void) |
0c564a53 | 8004 | { |
3673b8e4 SRRH |
8005 | int len; |
8006 | ||
02fd7f68 | 8007 | len = __stop_ftrace_eval_maps - __start_ftrace_eval_maps; |
f57a4143 | 8008 | trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len); |
3673b8e4 SRRH |
8009 | } |
8010 | ||
8011 | #ifdef CONFIG_MODULES | |
f57a4143 | 8012 | static void trace_module_add_evals(struct module *mod) |
3673b8e4 | 8013 | { |
99be647c | 8014 | if (!mod->num_trace_evals) |
3673b8e4 SRRH |
8015 | return; |
8016 | ||
8017 | /* | |
8018 | * Modules with bad taint do not have events created, do | |
8019 | * not bother with enums either. | |
8020 | */ | |
8021 | if (trace_module_has_bad_taint(mod)) | |
8022 | return; | |
8023 | ||
f57a4143 | 8024 | trace_insert_eval_map(mod, mod->trace_evals, mod->num_trace_evals); |
3673b8e4 SRRH |
8025 | } |
8026 | ||
681bec03 | 8027 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
f57a4143 | 8028 | static void trace_module_remove_evals(struct module *mod) |
9828413d | 8029 | { |
23bf8cb8 JL |
8030 | union trace_eval_map_item *map; |
8031 | union trace_eval_map_item **last = &trace_eval_maps; | |
9828413d | 8032 | |
99be647c | 8033 | if (!mod->num_trace_evals) |
9828413d SRRH |
8034 | return; |
8035 | ||
1793ed93 | 8036 | mutex_lock(&trace_eval_mutex); |
9828413d | 8037 | |
23bf8cb8 | 8038 | map = trace_eval_maps; |
9828413d SRRH |
8039 | |
8040 | while (map) { | |
8041 | if (map->head.mod == mod) | |
8042 | break; | |
5f60b351 | 8043 | map = trace_eval_jmp_to_tail(map); |
9828413d SRRH |
8044 | last = &map->tail.next; |
8045 | map = map->tail.next; | |
8046 | } | |
8047 | if (!map) | |
8048 | goto out; | |
8049 | ||
5f60b351 | 8050 | *last = trace_eval_jmp_to_tail(map)->tail.next; |
9828413d SRRH |
8051 | kfree(map); |
8052 | out: | |
1793ed93 | 8053 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
8054 | } |
8055 | #else | |
f57a4143 | 8056 | static inline void trace_module_remove_evals(struct module *mod) { } |
681bec03 | 8057 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 8058 | |
3673b8e4 SRRH |
8059 | static int trace_module_notify(struct notifier_block *self, |
8060 | unsigned long val, void *data) | |
8061 | { | |
8062 | struct module *mod = data; | |
8063 | ||
8064 | switch (val) { | |
8065 | case MODULE_STATE_COMING: | |
f57a4143 | 8066 | trace_module_add_evals(mod); |
3673b8e4 | 8067 | break; |
9828413d | 8068 | case MODULE_STATE_GOING: |
f57a4143 | 8069 | trace_module_remove_evals(mod); |
9828413d | 8070 | break; |
3673b8e4 SRRH |
8071 | } |
8072 | ||
8073 | return 0; | |
0c564a53 SRRH |
8074 | } |
8075 | ||
3673b8e4 SRRH |
8076 | static struct notifier_block trace_module_nb = { |
8077 | .notifier_call = trace_module_notify, | |
8078 | .priority = 0, | |
8079 | }; | |
9828413d | 8080 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 8081 | |
8434dc93 | 8082 | static __init int tracer_init_tracefs(void) |
bc0c38d1 SR |
8083 | { |
8084 | struct dentry *d_tracer; | |
bc0c38d1 | 8085 | |
7e53bd42 LJ |
8086 | trace_access_lock_init(); |
8087 | ||
bc0c38d1 | 8088 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 8089 | if (IS_ERR(d_tracer)) |
ed6f1c99 | 8090 | return 0; |
bc0c38d1 | 8091 | |
8434dc93 | 8092 | init_tracer_tracefs(&global_trace, d_tracer); |
501c2375 | 8093 | ftrace_init_tracefs_toplevel(&global_trace, d_tracer); |
bc0c38d1 | 8094 | |
5452af66 | 8095 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6508fa76 | 8096 | &global_trace, &tracing_thresh_fops); |
a8259075 | 8097 | |
339ae5d3 | 8098 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
8099 | NULL, &tracing_readme_fops); |
8100 | ||
69abe6a5 AP |
8101 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
8102 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 8103 | |
939c7a4f YY |
8104 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
8105 | NULL, &tracing_saved_cmdlines_size_fops); | |
8106 | ||
99c621d7 MS |
8107 | trace_create_file("saved_tgids", 0444, d_tracer, |
8108 | NULL, &tracing_saved_tgids_fops); | |
8109 | ||
5f60b351 | 8110 | trace_eval_init(); |
0c564a53 | 8111 | |
f57a4143 | 8112 | trace_create_eval_file(d_tracer); |
9828413d | 8113 | |
3673b8e4 SRRH |
8114 | #ifdef CONFIG_MODULES |
8115 | register_module_notifier(&trace_module_nb); | |
8116 | #endif | |
8117 | ||
bc0c38d1 | 8118 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
8119 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
8120 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 8121 | #endif |
b04cc6b1 | 8122 | |
277ba044 | 8123 | create_trace_instances(d_tracer); |
5452af66 | 8124 | |
37aea98b | 8125 | update_tracer_options(&global_trace); |
09d23a1d | 8126 | |
b5ad384e | 8127 | return 0; |
bc0c38d1 SR |
8128 | } |
8129 | ||
3f5a54e3 SR |
8130 | static int trace_panic_handler(struct notifier_block *this, |
8131 | unsigned long event, void *unused) | |
8132 | { | |
944ac425 | 8133 | if (ftrace_dump_on_oops) |
cecbca96 | 8134 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
8135 | return NOTIFY_OK; |
8136 | } | |
8137 | ||
8138 | static struct notifier_block trace_panic_notifier = { | |
8139 | .notifier_call = trace_panic_handler, | |
8140 | .next = NULL, | |
8141 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
8142 | }; | |
8143 | ||
8144 | static int trace_die_handler(struct notifier_block *self, | |
8145 | unsigned long val, | |
8146 | void *data) | |
8147 | { | |
8148 | switch (val) { | |
8149 | case DIE_OOPS: | |
944ac425 | 8150 | if (ftrace_dump_on_oops) |
cecbca96 | 8151 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
8152 | break; |
8153 | default: | |
8154 | break; | |
8155 | } | |
8156 | return NOTIFY_OK; | |
8157 | } | |
8158 | ||
8159 | static struct notifier_block trace_die_notifier = { | |
8160 | .notifier_call = trace_die_handler, | |
8161 | .priority = 200 | |
8162 | }; | |
8163 | ||
8164 | /* | |
8165 | * printk is set to max of 1024, we really don't need it that big. | |
8166 | * Nothing should be printing 1000 characters anyway. | |
8167 | */ | |
8168 | #define TRACE_MAX_PRINT 1000 | |
8169 | ||
8170 | /* | |
8171 | * Define here KERN_TRACE so that we have one place to modify | |
8172 | * it if we decide to change what log level the ftrace dump | |
8173 | * should be at. | |
8174 | */ | |
428aee14 | 8175 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 8176 | |
955b61e5 | 8177 | void |
3f5a54e3 SR |
8178 | trace_printk_seq(struct trace_seq *s) |
8179 | { | |
8180 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
8181 | if (s->seq.len >= TRACE_MAX_PRINT) |
8182 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 8183 | |
820b75f6 SRRH |
8184 | /* |
8185 | * More paranoid code. Although the buffer size is set to | |
8186 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
8187 | * an extra layer of protection. | |
8188 | */ | |
8189 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
8190 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
8191 | |
8192 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 8193 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
8194 | |
8195 | printk(KERN_TRACE "%s", s->buffer); | |
8196 | ||
f9520750 | 8197 | trace_seq_init(s); |
3f5a54e3 SR |
8198 | } |
8199 | ||
955b61e5 JW |
8200 | void trace_init_global_iter(struct trace_iterator *iter) |
8201 | { | |
8202 | iter->tr = &global_trace; | |
2b6080f2 | 8203 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 8204 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 8205 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
8206 | |
8207 | if (iter->trace && iter->trace->open) | |
8208 | iter->trace->open(iter); | |
8209 | ||
8210 | /* Annotate start of buffers if we had overruns */ | |
8211 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
8212 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
8213 | ||
8214 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
8215 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
8216 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
8217 | } |
8218 | ||
7fe70b57 | 8219 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 8220 | { |
3f5a54e3 SR |
8221 | /* use static because iter can be a bit big for the stack */ |
8222 | static struct trace_iterator iter; | |
7fe70b57 | 8223 | static atomic_t dump_running; |
983f938a | 8224 | struct trace_array *tr = &global_trace; |
cf586b61 | 8225 | unsigned int old_userobj; |
d769041f SR |
8226 | unsigned long flags; |
8227 | int cnt = 0, cpu; | |
3f5a54e3 | 8228 | |
7fe70b57 SRRH |
8229 | /* Only allow one dump user at a time. */ |
8230 | if (atomic_inc_return(&dump_running) != 1) { | |
8231 | atomic_dec(&dump_running); | |
8232 | return; | |
8233 | } | |
3f5a54e3 | 8234 | |
7fe70b57 SRRH |
8235 | /* |
8236 | * Always turn off tracing when we dump. | |
8237 | * We don't need to show trace output of what happens | |
8238 | * between multiple crashes. | |
8239 | * | |
8240 | * If the user does a sysrq-z, then they can re-enable | |
8241 | * tracing with echo 1 > tracing_on. | |
8242 | */ | |
0ee6b6cf | 8243 | tracing_off(); |
cf586b61 | 8244 | |
7fe70b57 | 8245 | local_irq_save(flags); |
cd71265a | 8246 | printk_nmi_direct_enter(); |
3f5a54e3 | 8247 | |
38dbe0b1 | 8248 | /* Simulate the iterator */ |
955b61e5 JW |
8249 | trace_init_global_iter(&iter); |
8250 | ||
d769041f | 8251 | for_each_tracing_cpu(cpu) { |
5e2d5ef8 | 8252 | atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); |
d769041f SR |
8253 | } |
8254 | ||
983f938a | 8255 | old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; |
cf586b61 | 8256 | |
b54d3de9 | 8257 | /* don't look at user memory in panic mode */ |
983f938a | 8258 | tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; |
b54d3de9 | 8259 | |
cecbca96 FW |
8260 | switch (oops_dump_mode) { |
8261 | case DUMP_ALL: | |
ae3b5093 | 8262 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
8263 | break; |
8264 | case DUMP_ORIG: | |
8265 | iter.cpu_file = raw_smp_processor_id(); | |
8266 | break; | |
8267 | case DUMP_NONE: | |
8268 | goto out_enable; | |
8269 | default: | |
8270 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 8271 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
8272 | } |
8273 | ||
8274 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 8275 | |
7fe70b57 SRRH |
8276 | /* Did function tracer already get disabled? */ |
8277 | if (ftrace_is_dead()) { | |
8278 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
8279 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
8280 | } | |
8281 | ||
3f5a54e3 SR |
8282 | /* |
8283 | * We need to stop all tracing on all CPUS to read the | |
8284 | * the next buffer. This is a bit expensive, but is | |
8285 | * not done often. We fill all what we can read, | |
8286 | * and then release the locks again. | |
8287 | */ | |
8288 | ||
3f5a54e3 SR |
8289 | while (!trace_empty(&iter)) { |
8290 | ||
8291 | if (!cnt) | |
8292 | printk(KERN_TRACE "---------------------------------\n"); | |
8293 | ||
8294 | cnt++; | |
8295 | ||
50bbae7d | 8296 | trace_iterator_reset(&iter); |
3f5a54e3 | 8297 | iter.iter_flags |= TRACE_FILE_LAT_FMT; |
3f5a54e3 | 8298 | |
955b61e5 | 8299 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
8300 | int ret; |
8301 | ||
8302 | ret = print_trace_line(&iter); | |
8303 | if (ret != TRACE_TYPE_NO_CONSUME) | |
8304 | trace_consume(&iter); | |
3f5a54e3 | 8305 | } |
b892e5c8 | 8306 | touch_nmi_watchdog(); |
3f5a54e3 SR |
8307 | |
8308 | trace_printk_seq(&iter.seq); | |
8309 | } | |
8310 | ||
8311 | if (!cnt) | |
8312 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
8313 | else | |
8314 | printk(KERN_TRACE "---------------------------------\n"); | |
8315 | ||
cecbca96 | 8316 | out_enable: |
983f938a | 8317 | tr->trace_flags |= old_userobj; |
cf586b61 | 8318 | |
7fe70b57 SRRH |
8319 | for_each_tracing_cpu(cpu) { |
8320 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 8321 | } |
cd71265a PM |
8322 | atomic_dec(&dump_running); |
8323 | printk_nmi_direct_exit(); | |
cd891ae0 | 8324 | local_irq_restore(flags); |
3f5a54e3 | 8325 | } |
a8eecf22 | 8326 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 8327 | |
3928a8a2 | 8328 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 8329 | { |
73c5162a | 8330 | int ring_buf_size; |
9e01c1b7 | 8331 | int ret = -ENOMEM; |
4c11d7ae | 8332 | |
b5e87c05 SRRH |
8333 | /* |
8334 | * Make sure we don't accidently add more trace options | |
8335 | * than we have bits for. | |
8336 | */ | |
9a38a885 | 8337 | BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); |
b5e87c05 | 8338 | |
9e01c1b7 RR |
8339 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
8340 | goto out; | |
8341 | ||
ccfe9e42 | 8342 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 8343 | goto out_free_buffer_mask; |
4c11d7ae | 8344 | |
07d777fe SR |
8345 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
8346 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 8347 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
8348 | trace_printk_init_buffers(); |
8349 | ||
73c5162a SR |
8350 | /* To save memory, keep the ring buffer size to its minimum */ |
8351 | if (ring_buffer_expanded) | |
8352 | ring_buf_size = trace_buf_size; | |
8353 | else | |
8354 | ring_buf_size = 1; | |
8355 | ||
9e01c1b7 | 8356 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 8357 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 8358 | |
2b6080f2 SR |
8359 | raw_spin_lock_init(&global_trace.start_lock); |
8360 | ||
b32614c0 SAS |
8361 | /* |
8362 | * The prepare callbacks allocates some memory for the ring buffer. We | |
8363 | * don't free the buffer if the if the CPU goes down. If we were to free | |
8364 | * the buffer, then the user would lose any trace that was in the | |
8365 | * buffer. The memory will be removed once the "instance" is removed. | |
8366 | */ | |
8367 | ret = cpuhp_setup_state_multi(CPUHP_TRACE_RB_PREPARE, | |
8368 | "trace/RB:preapre", trace_rb_cpu_prepare, | |
8369 | NULL); | |
8370 | if (ret < 0) | |
8371 | goto out_free_cpumask; | |
2c4a33ab | 8372 | /* Used for event triggers */ |
147d88e0 | 8373 | ret = -ENOMEM; |
2c4a33ab SRRH |
8374 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); |
8375 | if (!temp_buffer) | |
b32614c0 | 8376 | goto out_rm_hp_state; |
2c4a33ab | 8377 | |
939c7a4f YY |
8378 | if (trace_create_savedcmd() < 0) |
8379 | goto out_free_temp_buffer; | |
8380 | ||
9e01c1b7 | 8381 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 8382 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
8383 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
8384 | WARN_ON(1); | |
939c7a4f | 8385 | goto out_free_savedcmd; |
4c11d7ae | 8386 | } |
a7603ff4 | 8387 | |
499e5470 SR |
8388 | if (global_trace.buffer_disabled) |
8389 | tracing_off(); | |
4c11d7ae | 8390 | |
e1e232ca SR |
8391 | if (trace_boot_clock) { |
8392 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
8393 | if (ret < 0) | |
a395d6a7 JP |
8394 | pr_warn("Trace clock %s not defined, going back to default\n", |
8395 | trace_boot_clock); | |
e1e232ca SR |
8396 | } |
8397 | ||
ca164318 SRRH |
8398 | /* |
8399 | * register_tracer() might reference current_trace, so it | |
8400 | * needs to be set before we register anything. This is | |
8401 | * just a bootstrap of current_trace anyway. | |
8402 | */ | |
2b6080f2 SR |
8403 | global_trace.current_trace = &nop_trace; |
8404 | ||
0b9b12c1 SRRH |
8405 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
8406 | ||
4104d326 SRRH |
8407 | ftrace_init_global_array_ops(&global_trace); |
8408 | ||
9a38a885 SRRH |
8409 | init_trace_flags_index(&global_trace); |
8410 | ||
ca164318 SRRH |
8411 | register_tracer(&nop_trace); |
8412 | ||
dbeafd0d SRV |
8413 | /* Function tracing may start here (via kernel command line) */ |
8414 | init_function_trace(); | |
8415 | ||
60a11774 SR |
8416 | /* All seems OK, enable tracing */ |
8417 | tracing_disabled = 0; | |
3928a8a2 | 8418 | |
3f5a54e3 SR |
8419 | atomic_notifier_chain_register(&panic_notifier_list, |
8420 | &trace_panic_notifier); | |
8421 | ||
8422 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 8423 | |
ae63b31e SR |
8424 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
8425 | ||
8426 | INIT_LIST_HEAD(&global_trace.systems); | |
8427 | INIT_LIST_HEAD(&global_trace.events); | |
8428 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
8429 | ||
a4d1e688 | 8430 | apply_trace_boot_options(); |
7bcfaf54 | 8431 | |
77fd5c15 SRRH |
8432 | register_snapshot_cmd(); |
8433 | ||
2fc1dfbe | 8434 | return 0; |
3f5a54e3 | 8435 | |
939c7a4f YY |
8436 | out_free_savedcmd: |
8437 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
8438 | out_free_temp_buffer: |
8439 | ring_buffer_free(temp_buffer); | |
b32614c0 SAS |
8440 | out_rm_hp_state: |
8441 | cpuhp_remove_multi_state(CPUHP_TRACE_RB_PREPARE); | |
9e01c1b7 | 8442 | out_free_cpumask: |
ccfe9e42 | 8443 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
8444 | out_free_buffer_mask: |
8445 | free_cpumask_var(tracing_buffer_mask); | |
8446 | out: | |
8447 | return ret; | |
bc0c38d1 | 8448 | } |
b2821ae6 | 8449 | |
e725c731 | 8450 | void __init early_trace_init(void) |
5f893b26 | 8451 | { |
0daa2302 SRRH |
8452 | if (tracepoint_printk) { |
8453 | tracepoint_print_iter = | |
8454 | kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); | |
8455 | if (WARN_ON(!tracepoint_print_iter)) | |
8456 | tracepoint_printk = 0; | |
42391745 SRRH |
8457 | else |
8458 | static_key_enable(&tracepoint_printk_key.key); | |
0daa2302 | 8459 | } |
5f893b26 | 8460 | tracer_alloc_buffers(); |
e725c731 SRV |
8461 | } |
8462 | ||
8463 | void __init trace_init(void) | |
8464 | { | |
0c564a53 | 8465 | trace_event_init(); |
5f893b26 SRRH |
8466 | } |
8467 | ||
b2821ae6 SR |
8468 | __init static int clear_boot_tracer(void) |
8469 | { | |
8470 | /* | |
8471 | * The default tracer at boot buffer is an init section. | |
8472 | * This function is called in lateinit. If we did not | |
8473 | * find the boot tracer, then clear it out, to prevent | |
8474 | * later registration from accessing the buffer that is | |
8475 | * about to be freed. | |
8476 | */ | |
8477 | if (!default_bootup_tracer) | |
8478 | return 0; | |
8479 | ||
8480 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
8481 | default_bootup_tracer); | |
8482 | default_bootup_tracer = NULL; | |
8483 | ||
8484 | return 0; | |
8485 | } | |
8486 | ||
8434dc93 | 8487 | fs_initcall(tracer_init_tracefs); |
4bb0f0e7 | 8488 | late_initcall_sync(clear_boot_tracer); |