]>
Commit | Line | Data |
---|---|---|
bc5c5ec0 | 1 | #include "git-compat-util.h" |
36bf1958 | 2 | #include "alloc.h" |
7531e4b6 | 3 | #include "config.h" |
04155bda | 4 | #include "entry.h" |
f394e093 | 5 | #include "gettext.h" |
d1cbe1e6 | 6 | #include "hash.h" |
41771fa4 | 7 | #include "hex.h" |
04155bda | 8 | #include "parallel-checkout.h" |
e9e8adf1 | 9 | #include "pkt-line.h" |
1c4d6f46 | 10 | #include "progress.h" |
08c46a49 | 11 | #include "read-cache-ll.h" |
e9e8adf1 MT |
12 | #include "run-command.h" |
13 | #include "sigchain.h" | |
04155bda | 14 | #include "streaming.h" |
cb2a5135 | 15 | #include "symlinks.h" |
7531e4b6 | 16 | #include "thread-utils.h" |
6a7bc9d1 | 17 | #include "trace2.h" |
d5ebb50d | 18 | #include "wrapper.h" |
04155bda | 19 | |
e9e8adf1 MT |
20 | struct pc_worker { |
21 | struct child_process cp; | |
22 | size_t next_item_to_complete, nr_items_to_complete; | |
04155bda MT |
23 | }; |
24 | ||
25 | struct parallel_checkout { | |
26 | enum pc_status status; | |
27 | struct parallel_checkout_item *items; /* The parallel checkout queue. */ | |
28 | size_t nr, alloc; | |
1c4d6f46 MT |
29 | struct progress *progress; |
30 | unsigned int *progress_cnt; | |
04155bda MT |
31 | }; |
32 | ||
33 | static struct parallel_checkout parallel_checkout; | |
34 | ||
35 | enum pc_status parallel_checkout_status(void) | |
36 | { | |
37 | return parallel_checkout.status; | |
38 | } | |
39 | ||
7531e4b6 MT |
40 | static const int DEFAULT_THRESHOLD_FOR_PARALLELISM = 100; |
41 | static const int DEFAULT_NUM_WORKERS = 1; | |
42 | ||
43 | void get_parallel_checkout_configs(int *num_workers, int *threshold) | |
44 | { | |
87094fc2 MT |
45 | char *env_workers = getenv("GIT_TEST_CHECKOUT_WORKERS"); |
46 | ||
47 | if (env_workers && *env_workers) { | |
48 | if (strtol_i(env_workers, 10, num_workers)) { | |
1a8aea85 JNA |
49 | die(_("invalid value for '%s': '%s'"), |
50 | "GIT_TEST_CHECKOUT_WORKERS", env_workers); | |
87094fc2 MT |
51 | } |
52 | if (*num_workers < 1) | |
53 | *num_workers = online_cpus(); | |
54 | ||
55 | *threshold = 0; | |
56 | return; | |
57 | } | |
58 | ||
7531e4b6 MT |
59 | if (git_config_get_int("checkout.workers", num_workers)) |
60 | *num_workers = DEFAULT_NUM_WORKERS; | |
61 | else if (*num_workers < 1) | |
62 | *num_workers = online_cpus(); | |
63 | ||
64 | if (git_config_get_int("checkout.thresholdForParallelism", threshold)) | |
65 | *threshold = DEFAULT_THRESHOLD_FOR_PARALLELISM; | |
66 | } | |
67 | ||
04155bda MT |
68 | void init_parallel_checkout(void) |
69 | { | |
70 | if (parallel_checkout.status != PC_UNINITIALIZED) | |
71 | BUG("parallel checkout already initialized"); | |
72 | ||
73 | parallel_checkout.status = PC_ACCEPTING_ENTRIES; | |
74 | } | |
75 | ||
76 | static void finish_parallel_checkout(void) | |
77 | { | |
78 | if (parallel_checkout.status == PC_UNINITIALIZED) | |
79 | BUG("cannot finish parallel checkout: not initialized yet"); | |
80 | ||
81 | free(parallel_checkout.items); | |
82 | memset(¶llel_checkout, 0, sizeof(parallel_checkout)); | |
83 | } | |
84 | ||
85 | static int is_eligible_for_parallel_checkout(const struct cache_entry *ce, | |
86 | const struct conv_attrs *ca) | |
87 | { | |
88 | enum conv_attrs_classification c; | |
e9e8adf1 | 89 | size_t packed_item_size; |
04155bda MT |
90 | |
91 | /* | |
92 | * Symlinks cannot be checked out in parallel as, in case of path | |
93 | * collision, they could racily replace leading directories of other | |
94 | * entries being checked out. Submodules are checked out in child | |
95 | * processes, which have their own parallel checkout queues. | |
96 | */ | |
97 | if (!S_ISREG(ce->ce_mode)) | |
98 | return 0; | |
99 | ||
e9e8adf1 MT |
100 | packed_item_size = sizeof(struct pc_item_fixed_portion) + ce->ce_namelen + |
101 | (ca->working_tree_encoding ? strlen(ca->working_tree_encoding) : 0); | |
102 | ||
103 | /* | |
104 | * The amount of data we send to the workers per checkout item is | |
105 | * typically small (75~300B). So unless we find an insanely huge path | |
106 | * of 64KB, we should never reach the 65KB limit of one pkt-line. If | |
107 | * that does happen, we let the sequential code handle the item. | |
108 | */ | |
109 | if (packed_item_size > LARGE_PACKET_DATA_MAX) | |
110 | return 0; | |
111 | ||
04155bda MT |
112 | c = classify_conv_attrs(ca); |
113 | switch (c) { | |
114 | case CA_CLASS_INCORE: | |
115 | return 1; | |
116 | ||
117 | case CA_CLASS_INCORE_FILTER: | |
118 | /* | |
119 | * It would be safe to allow concurrent instances of | |
120 | * single-file smudge filters, like rot13, but we should not | |
121 | * assume that all filters are parallel-process safe. So we | |
122 | * don't allow this. | |
123 | */ | |
124 | return 0; | |
125 | ||
126 | case CA_CLASS_INCORE_PROCESS: | |
127 | /* | |
128 | * The parallel queue and the delayed queue are not compatible, | |
129 | * so they must be kept completely separated. And we can't tell | |
130 | * if a long-running process will delay its response without | |
131 | * actually asking it to perform the filtering. Therefore, this | |
132 | * type of filter is not allowed in parallel checkout. | |
133 | * | |
134 | * Furthermore, there should only be one instance of the | |
135 | * long-running process filter as we don't know how it is | |
136 | * managing its own concurrency. So, spreading the entries that | |
137 | * requisite such a filter among the parallel workers would | |
138 | * require a lot more inter-process communication. We would | |
139 | * probably have to designate a single process to interact with | |
140 | * the filter and send all the necessary data to it, for each | |
141 | * entry. | |
142 | */ | |
143 | return 0; | |
144 | ||
145 | case CA_CLASS_STREAMABLE: | |
146 | return 1; | |
147 | ||
148 | default: | |
149 | BUG("unsupported conv_attrs classification '%d'", c); | |
150 | } | |
151 | } | |
152 | ||
611c7785 MT |
153 | int enqueue_checkout(struct cache_entry *ce, struct conv_attrs *ca, |
154 | int *checkout_counter) | |
04155bda MT |
155 | { |
156 | struct parallel_checkout_item *pc_item; | |
157 | ||
158 | if (parallel_checkout.status != PC_ACCEPTING_ENTRIES || | |
159 | !is_eligible_for_parallel_checkout(ce, ca)) | |
160 | return -1; | |
161 | ||
162 | ALLOC_GROW(parallel_checkout.items, parallel_checkout.nr + 1, | |
163 | parallel_checkout.alloc); | |
164 | ||
e9e8adf1 | 165 | pc_item = ¶llel_checkout.items[parallel_checkout.nr]; |
04155bda MT |
166 | pc_item->ce = ce; |
167 | memcpy(&pc_item->ca, ca, sizeof(pc_item->ca)); | |
168 | pc_item->status = PC_ITEM_PENDING; | |
e9e8adf1 | 169 | pc_item->id = parallel_checkout.nr; |
611c7785 | 170 | pc_item->checkout_counter = checkout_counter; |
e9e8adf1 | 171 | parallel_checkout.nr++; |
04155bda MT |
172 | |
173 | return 0; | |
174 | } | |
175 | ||
1c4d6f46 MT |
176 | size_t pc_queue_size(void) |
177 | { | |
178 | return parallel_checkout.nr; | |
179 | } | |
180 | ||
181 | static void advance_progress_meter(void) | |
182 | { | |
183 | if (parallel_checkout.progress) { | |
184 | (*parallel_checkout.progress_cnt)++; | |
185 | display_progress(parallel_checkout.progress, | |
186 | *parallel_checkout.progress_cnt); | |
187 | } | |
188 | } | |
189 | ||
04155bda MT |
190 | static int handle_results(struct checkout *state) |
191 | { | |
192 | int ret = 0; | |
193 | size_t i; | |
194 | int have_pending = 0; | |
195 | ||
196 | /* | |
197 | * We first update the successfully written entries with the collected | |
198 | * stat() data, so that they can be found by mark_colliding_entries(), | |
199 | * in the next loop, when necessary. | |
200 | */ | |
201 | for (i = 0; i < parallel_checkout.nr; i++) { | |
202 | struct parallel_checkout_item *pc_item = ¶llel_checkout.items[i]; | |
203 | if (pc_item->status == PC_ITEM_WRITTEN) | |
204 | update_ce_after_write(state, pc_item->ce, &pc_item->st); | |
205 | } | |
206 | ||
207 | for (i = 0; i < parallel_checkout.nr; i++) { | |
208 | struct parallel_checkout_item *pc_item = ¶llel_checkout.items[i]; | |
209 | ||
210 | switch(pc_item->status) { | |
211 | case PC_ITEM_WRITTEN: | |
611c7785 MT |
212 | if (pc_item->checkout_counter) |
213 | (*pc_item->checkout_counter)++; | |
04155bda MT |
214 | break; |
215 | case PC_ITEM_COLLIDED: | |
216 | /* | |
217 | * The entry could not be checked out due to a path | |
218 | * collision with another entry. Since there can only | |
219 | * be one entry of each colliding group on the disk, we | |
220 | * could skip trying to check out this one and move on. | |
221 | * However, this would leave the unwritten entries with | |
222 | * null stat() fields on the index, which could | |
223 | * potentially slow down subsequent operations that | |
224 | * require refreshing it: git would not be able to | |
225 | * trust st_size and would have to go to the filesystem | |
226 | * to see if the contents match (see ie_modified()). | |
227 | * | |
228 | * Instead, let's pay the overhead only once, now, and | |
229 | * call checkout_entry_ca() again for this file, to | |
230 | * have its stat() data stored in the index. This also | |
231 | * has the benefit of adding this entry and its | |
232 | * colliding pair to the collision report message. | |
233 | * Additionally, this overwriting behavior is consistent | |
234 | * with what the sequential checkout does, so it doesn't | |
235 | * add any extra overhead. | |
236 | */ | |
237 | ret |= checkout_entry_ca(pc_item->ce, &pc_item->ca, | |
611c7785 MT |
238 | state, NULL, |
239 | pc_item->checkout_counter); | |
1c4d6f46 | 240 | advance_progress_meter(); |
04155bda MT |
241 | break; |
242 | case PC_ITEM_PENDING: | |
243 | have_pending = 1; | |
244 | /* fall through */ | |
245 | case PC_ITEM_FAILED: | |
246 | ret = -1; | |
247 | break; | |
248 | default: | |
249 | BUG("unknown checkout item status in parallel checkout"); | |
250 | } | |
251 | } | |
252 | ||
253 | if (have_pending) | |
254 | error("parallel checkout finished with pending entries"); | |
255 | ||
256 | return ret; | |
257 | } | |
258 | ||
259 | static int reset_fd(int fd, const char *path) | |
260 | { | |
261 | if (lseek(fd, 0, SEEK_SET) != 0) | |
262 | return error_errno("failed to rewind descriptor of '%s'", path); | |
263 | if (ftruncate(fd, 0)) | |
264 | return error_errno("failed to truncate file '%s'", path); | |
265 | return 0; | |
266 | } | |
267 | ||
268 | static int write_pc_item_to_fd(struct parallel_checkout_item *pc_item, int fd, | |
269 | const char *path) | |
270 | { | |
271 | int ret; | |
272 | struct stream_filter *filter; | |
273 | struct strbuf buf = STRBUF_INIT; | |
274 | char *blob; | |
e9aa762c | 275 | size_t size; |
04155bda MT |
276 | ssize_t wrote; |
277 | ||
278 | /* Sanity check */ | |
279 | assert(is_eligible_for_parallel_checkout(pc_item->ce, &pc_item->ca)); | |
280 | ||
281 | filter = get_stream_filter_ca(&pc_item->ca, &pc_item->ce->oid); | |
282 | if (filter) { | |
283 | if (stream_blob_to_fd(fd, &pc_item->ce->oid, filter, 1)) { | |
284 | /* On error, reset fd to try writing without streaming */ | |
285 | if (reset_fd(fd, path)) | |
286 | return -1; | |
287 | } else { | |
288 | return 0; | |
289 | } | |
290 | } | |
291 | ||
292 | blob = read_blob_entry(pc_item->ce, &size); | |
293 | if (!blob) | |
294 | return error("cannot read object %s '%s'", | |
295 | oid_to_hex(&pc_item->ce->oid), pc_item->ce->name); | |
296 | ||
297 | /* | |
298 | * checkout metadata is used to give context for external process | |
299 | * filters. Files requiring such filters are not eligible for parallel | |
e9e8adf1 MT |
300 | * checkout, so pass NULL. Note: if that changes, the metadata must also |
301 | * be passed from the main process to the workers. | |
04155bda MT |
302 | */ |
303 | ret = convert_to_working_tree_ca(&pc_item->ca, pc_item->ce->name, | |
304 | blob, size, &buf, NULL); | |
305 | ||
306 | if (ret) { | |
307 | size_t newsize; | |
308 | free(blob); | |
309 | blob = strbuf_detach(&buf, &newsize); | |
310 | size = newsize; | |
311 | } | |
312 | ||
313 | wrote = write_in_full(fd, blob, size); | |
314 | free(blob); | |
315 | if (wrote < 0) | |
316 | return error("unable to write file '%s'", path); | |
317 | ||
318 | return 0; | |
319 | } | |
320 | ||
321 | static int close_and_clear(int *fd) | |
322 | { | |
323 | int ret = 0; | |
324 | ||
325 | if (*fd >= 0) { | |
326 | ret = close(*fd); | |
327 | *fd = -1; | |
328 | } | |
329 | ||
330 | return ret; | |
331 | } | |
332 | ||
e9e8adf1 MT |
333 | void write_pc_item(struct parallel_checkout_item *pc_item, |
334 | struct checkout *state) | |
04155bda MT |
335 | { |
336 | unsigned int mode = (pc_item->ce->ce_mode & 0100) ? 0777 : 0666; | |
337 | int fd = -1, fstat_done = 0; | |
338 | struct strbuf path = STRBUF_INIT; | |
339 | const char *dir_sep; | |
340 | ||
341 | strbuf_add(&path, state->base_dir, state->base_dir_len); | |
342 | strbuf_add(&path, pc_item->ce->name, pc_item->ce->ce_namelen); | |
343 | ||
344 | dir_sep = find_last_dir_sep(path.buf); | |
345 | ||
346 | /* | |
347 | * The leading dirs should have been already created by now. But, in | |
348 | * case of path collisions, one of the dirs could have been replaced by | |
349 | * a symlink (checked out after we enqueued this entry for parallel | |
350 | * checkout). Thus, we must check the leading dirs again. | |
351 | */ | |
352 | if (dir_sep && !has_dirs_only_path(path.buf, dir_sep - path.buf, | |
353 | state->base_dir_len)) { | |
354 | pc_item->status = PC_ITEM_COLLIDED; | |
6a7bc9d1 | 355 | trace2_data_string("pcheckout", NULL, "collision/dirname", path.buf); |
04155bda MT |
356 | goto out; |
357 | } | |
358 | ||
359 | fd = open(path.buf, O_WRONLY | O_CREAT | O_EXCL, mode); | |
360 | ||
361 | if (fd < 0) { | |
362 | if (errno == EEXIST || errno == EISDIR) { | |
363 | /* | |
364 | * Errors which probably represent a path collision. | |
365 | * Suppress the error message and mark the item to be | |
366 | * retried later, sequentially. ENOTDIR and ENOENT are | |
367 | * also interesting, but the above has_dirs_only_path() | |
368 | * call should have already caught these cases. | |
369 | */ | |
370 | pc_item->status = PC_ITEM_COLLIDED; | |
6a7bc9d1 MT |
371 | trace2_data_string("pcheckout", NULL, |
372 | "collision/basename", path.buf); | |
04155bda MT |
373 | } else { |
374 | error_errno("failed to open file '%s'", path.buf); | |
375 | pc_item->status = PC_ITEM_FAILED; | |
376 | } | |
377 | goto out; | |
378 | } | |
379 | ||
380 | if (write_pc_item_to_fd(pc_item, fd, path.buf)) { | |
381 | /* Error was already reported. */ | |
382 | pc_item->status = PC_ITEM_FAILED; | |
383 | close_and_clear(&fd); | |
384 | unlink(path.buf); | |
385 | goto out; | |
386 | } | |
387 | ||
388 | fstat_done = fstat_checkout_output(fd, state, &pc_item->st); | |
389 | ||
390 | if (close_and_clear(&fd)) { | |
391 | error_errno("unable to close file '%s'", path.buf); | |
392 | pc_item->status = PC_ITEM_FAILED; | |
393 | goto out; | |
394 | } | |
395 | ||
396 | if (state->refresh_cache && !fstat_done && lstat(path.buf, &pc_item->st) < 0) { | |
397 | error_errno("unable to stat just-written file '%s'", path.buf); | |
398 | pc_item->status = PC_ITEM_FAILED; | |
399 | goto out; | |
400 | } | |
401 | ||
402 | pc_item->status = PC_ITEM_WRITTEN; | |
403 | ||
404 | out: | |
405 | strbuf_release(&path); | |
406 | } | |
407 | ||
e9e8adf1 MT |
408 | static void send_one_item(int fd, struct parallel_checkout_item *pc_item) |
409 | { | |
410 | size_t len_data; | |
411 | char *data, *variant; | |
412 | struct pc_item_fixed_portion *fixed_portion; | |
413 | const char *working_tree_encoding = pc_item->ca.working_tree_encoding; | |
414 | size_t name_len = pc_item->ce->ce_namelen; | |
415 | size_t working_tree_encoding_len = working_tree_encoding ? | |
416 | strlen(working_tree_encoding) : 0; | |
417 | ||
418 | /* | |
419 | * Any changes in the calculation of the message size must also be made | |
420 | * in is_eligible_for_parallel_checkout(). | |
421 | */ | |
422 | len_data = sizeof(struct pc_item_fixed_portion) + name_len + | |
423 | working_tree_encoding_len; | |
424 | ||
3d20ed27 | 425 | data = xmalloc(len_data); |
e9e8adf1 MT |
426 | |
427 | fixed_portion = (struct pc_item_fixed_portion *)data; | |
428 | fixed_portion->id = pc_item->id; | |
429 | fixed_portion->ce_mode = pc_item->ce->ce_mode; | |
430 | fixed_portion->crlf_action = pc_item->ca.crlf_action; | |
431 | fixed_portion->ident = pc_item->ca.ident; | |
432 | fixed_portion->name_len = name_len; | |
433 | fixed_portion->working_tree_encoding_len = working_tree_encoding_len; | |
434 | /* | |
3d20ed27 MT |
435 | * We pad the unused bytes in the hash array because, otherwise, |
436 | * Valgrind would complain about passing uninitialized bytes to a | |
437 | * write() syscall. The warning doesn't represent any real risk here, | |
438 | * but it could hinder the detection of actual errors. | |
e9e8adf1 | 439 | */ |
3d20ed27 | 440 | oidcpy_with_padding(&fixed_portion->oid, &pc_item->ce->oid); |
e9e8adf1 MT |
441 | |
442 | variant = data + sizeof(*fixed_portion); | |
443 | if (working_tree_encoding_len) { | |
444 | memcpy(variant, working_tree_encoding, working_tree_encoding_len); | |
445 | variant += working_tree_encoding_len; | |
446 | } | |
447 | memcpy(variant, pc_item->ce->name, name_len); | |
448 | ||
449 | packet_write(fd, data, len_data); | |
450 | ||
451 | free(data); | |
452 | } | |
453 | ||
454 | static void send_batch(int fd, size_t start, size_t nr) | |
455 | { | |
456 | size_t i; | |
457 | sigchain_push(SIGPIPE, SIG_IGN); | |
458 | for (i = 0; i < nr; i++) | |
459 | send_one_item(fd, ¶llel_checkout.items[start + i]); | |
460 | packet_flush(fd); | |
461 | sigchain_pop(SIGPIPE); | |
462 | } | |
463 | ||
464 | static struct pc_worker *setup_workers(struct checkout *state, int num_workers) | |
465 | { | |
466 | struct pc_worker *workers; | |
467 | int i, workers_with_one_extra_item; | |
468 | size_t base_batch_size, batch_beginning = 0; | |
469 | ||
470 | ALLOC_ARRAY(workers, num_workers); | |
471 | ||
472 | for (i = 0; i < num_workers; i++) { | |
473 | struct child_process *cp = &workers[i].cp; | |
474 | ||
475 | child_process_init(cp); | |
476 | cp->git_cmd = 1; | |
477 | cp->in = -1; | |
478 | cp->out = -1; | |
479 | cp->clean_on_exit = 1; | |
480 | strvec_push(&cp->args, "checkout--worker"); | |
481 | if (state->base_dir_len) | |
482 | strvec_pushf(&cp->args, "--prefix=%s", state->base_dir); | |
483 | if (start_command(cp)) | |
484 | die("failed to spawn checkout worker"); | |
485 | } | |
486 | ||
487 | base_batch_size = parallel_checkout.nr / num_workers; | |
488 | workers_with_one_extra_item = parallel_checkout.nr % num_workers; | |
489 | ||
490 | for (i = 0; i < num_workers; i++) { | |
491 | struct pc_worker *worker = &workers[i]; | |
492 | size_t batch_size = base_batch_size; | |
493 | ||
494 | /* distribute the extra work evenly */ | |
495 | if (i < workers_with_one_extra_item) | |
496 | batch_size++; | |
497 | ||
498 | send_batch(worker->cp.in, batch_beginning, batch_size); | |
499 | worker->next_item_to_complete = batch_beginning; | |
500 | worker->nr_items_to_complete = batch_size; | |
501 | ||
502 | batch_beginning += batch_size; | |
503 | } | |
504 | ||
505 | return workers; | |
506 | } | |
507 | ||
508 | static void finish_workers(struct pc_worker *workers, int num_workers) | |
509 | { | |
510 | int i; | |
511 | ||
512 | /* | |
513 | * Close pipes before calling finish_command() to let the workers | |
514 | * exit asynchronously and avoid spending extra time on wait(). | |
515 | */ | |
516 | for (i = 0; i < num_workers; i++) { | |
517 | struct child_process *cp = &workers[i].cp; | |
518 | if (cp->in >= 0) | |
519 | close(cp->in); | |
520 | if (cp->out >= 0) | |
521 | close(cp->out); | |
522 | } | |
523 | ||
524 | for (i = 0; i < num_workers; i++) { | |
525 | int rc = finish_command(&workers[i].cp); | |
526 | if (rc > 128) { | |
527 | /* | |
528 | * For a normal non-zero exit, the worker should have | |
529 | * already printed something useful to stderr. But a | |
530 | * death by signal should be mentioned to the user. | |
531 | */ | |
532 | error("checkout worker %d died of signal %d", i, rc - 128); | |
533 | } | |
534 | } | |
535 | ||
536 | free(workers); | |
537 | } | |
538 | ||
539 | static inline void assert_pc_item_result_size(int got, int exp) | |
540 | { | |
541 | if (got != exp) | |
542 | BUG("wrong result size from checkout worker (got %dB, exp %dB)", | |
543 | got, exp); | |
544 | } | |
545 | ||
546 | static void parse_and_save_result(const char *buffer, int len, | |
547 | struct pc_worker *worker) | |
548 | { | |
549 | struct pc_item_result *res; | |
550 | struct parallel_checkout_item *pc_item; | |
551 | struct stat *st = NULL; | |
552 | ||
553 | if (len < PC_ITEM_RESULT_BASE_SIZE) | |
554 | BUG("too short result from checkout worker (got %dB, exp >=%dB)", | |
555 | len, (int)PC_ITEM_RESULT_BASE_SIZE); | |
556 | ||
557 | res = (struct pc_item_result *)buffer; | |
558 | ||
559 | /* | |
560 | * Worker should send either the full result struct on success, or | |
561 | * just the base (i.e. no stat data), otherwise. | |
562 | */ | |
563 | if (res->status == PC_ITEM_WRITTEN) { | |
564 | assert_pc_item_result_size(len, (int)sizeof(struct pc_item_result)); | |
565 | st = &res->st; | |
566 | } else { | |
567 | assert_pc_item_result_size(len, (int)PC_ITEM_RESULT_BASE_SIZE); | |
568 | } | |
569 | ||
570 | if (!worker->nr_items_to_complete) | |
571 | BUG("received result from supposedly finished checkout worker"); | |
572 | if (res->id != worker->next_item_to_complete) | |
573 | BUG("unexpected item id from checkout worker (got %"PRIuMAX", exp %"PRIuMAX")", | |
574 | (uintmax_t)res->id, (uintmax_t)worker->next_item_to_complete); | |
575 | ||
576 | worker->next_item_to_complete++; | |
577 | worker->nr_items_to_complete--; | |
578 | ||
579 | pc_item = ¶llel_checkout.items[res->id]; | |
580 | pc_item->status = res->status; | |
581 | if (st) | |
582 | pc_item->st = *st; | |
1c4d6f46 MT |
583 | |
584 | if (res->status != PC_ITEM_COLLIDED) | |
585 | advance_progress_meter(); | |
e9e8adf1 MT |
586 | } |
587 | ||
588 | static void gather_results_from_workers(struct pc_worker *workers, | |
589 | int num_workers) | |
590 | { | |
591 | int i, active_workers = num_workers; | |
592 | struct pollfd *pfds; | |
593 | ||
594 | CALLOC_ARRAY(pfds, num_workers); | |
595 | for (i = 0; i < num_workers; i++) { | |
596 | pfds[i].fd = workers[i].cp.out; | |
597 | pfds[i].events = POLLIN; | |
598 | } | |
599 | ||
600 | while (active_workers) { | |
601 | int nr = poll(pfds, num_workers, -1); | |
602 | ||
603 | if (nr < 0) { | |
604 | if (errno == EINTR) | |
605 | continue; | |
606 | die_errno("failed to poll checkout workers"); | |
607 | } | |
608 | ||
609 | for (i = 0; i < num_workers && nr > 0; i++) { | |
610 | struct pc_worker *worker = &workers[i]; | |
611 | struct pollfd *pfd = &pfds[i]; | |
612 | ||
613 | if (!pfd->revents) | |
614 | continue; | |
615 | ||
616 | if (pfd->revents & POLLIN) { | |
ec9a37d6 | 617 | int len = packet_read(pfd->fd, packet_buffer, |
e9e8adf1 MT |
618 | sizeof(packet_buffer), 0); |
619 | ||
620 | if (len < 0) { | |
621 | BUG("packet_read() returned negative value"); | |
622 | } else if (!len) { | |
623 | pfd->fd = -1; | |
624 | active_workers--; | |
625 | } else { | |
626 | parse_and_save_result(packet_buffer, | |
627 | len, worker); | |
628 | } | |
629 | } else if (pfd->revents & POLLHUP) { | |
630 | pfd->fd = -1; | |
631 | active_workers--; | |
632 | } else if (pfd->revents & (POLLNVAL | POLLERR)) { | |
633 | die("error polling from checkout worker"); | |
634 | } | |
635 | ||
636 | nr--; | |
637 | } | |
638 | } | |
639 | ||
640 | free(pfds); | |
641 | } | |
642 | ||
04155bda MT |
643 | static void write_items_sequentially(struct checkout *state) |
644 | { | |
645 | size_t i; | |
646 | ||
1c4d6f46 MT |
647 | for (i = 0; i < parallel_checkout.nr; i++) { |
648 | struct parallel_checkout_item *pc_item = ¶llel_checkout.items[i]; | |
649 | write_pc_item(pc_item, state); | |
650 | if (pc_item->status != PC_ITEM_COLLIDED) | |
651 | advance_progress_meter(); | |
652 | } | |
04155bda MT |
653 | } |
654 | ||
1c4d6f46 MT |
655 | int run_parallel_checkout(struct checkout *state, int num_workers, int threshold, |
656 | struct progress *progress, unsigned int *progress_cnt) | |
04155bda | 657 | { |
7531e4b6 | 658 | int ret; |
04155bda MT |
659 | |
660 | if (parallel_checkout.status != PC_ACCEPTING_ENTRIES) | |
661 | BUG("cannot run parallel checkout: uninitialized or already running"); | |
662 | ||
663 | parallel_checkout.status = PC_RUNNING; | |
1c4d6f46 MT |
664 | parallel_checkout.progress = progress; |
665 | parallel_checkout.progress_cnt = progress_cnt; | |
04155bda | 666 | |
e9e8adf1 MT |
667 | if (parallel_checkout.nr < num_workers) |
668 | num_workers = parallel_checkout.nr; | |
669 | ||
7531e4b6 | 670 | if (num_workers <= 1 || parallel_checkout.nr < threshold) { |
e9e8adf1 MT |
671 | write_items_sequentially(state); |
672 | } else { | |
673 | struct pc_worker *workers = setup_workers(state, num_workers); | |
674 | gather_results_from_workers(workers, num_workers); | |
675 | finish_workers(workers, num_workers); | |
676 | } | |
677 | ||
04155bda MT |
678 | ret = handle_results(state); |
679 | ||
680 | finish_parallel_checkout(); | |
681 | return ret; | |
682 | } |