[thirdparty/linux.git] / kernel / trace / trace_boot.c

// SPDX-License-Identifier: GPL-2.0
/*
 * trace_boot.c
 * Tracing kernel boot-time
 */

#define pr_fmt(fmt)	"trace_boot: " fmt

#include <linux/bootconfig.h>
#include <linux/cpumask.h>
#include <linux/ftrace.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mutex.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/trace.h>
#include <linux/trace_events.h>

#include "trace.h"

#define MAX_BUF_LEN 256

static void __init
trace_boot_set_instance_options(struct trace_array *tr, struct xbc_node *node)
{
	struct xbc_node *anode;
	const char *p;
	char buf[MAX_BUF_LEN];
	unsigned long v = 0;

	/* Common ftrace options */
	xbc_node_for_each_array_value(node, "options", anode, p) {
		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) {
			pr_err("String is too long: %s\n", p);
			continue;
		}

		if (trace_set_options(tr, buf) < 0)
			pr_err("Failed to set option: %s\n", buf);
	}

	p = xbc_node_find_value(node, "trace_clock", NULL);
	if (p && *p != '\0') {
		if (tracing_set_clock(tr, p) < 0)
			pr_err("Failed to set trace clock: %s\n", p);
	}

	p = xbc_node_find_value(node, "buffer_size", NULL);
	if (p && *p != '\0') {
		v = memparse(p, NULL);
		if (v < PAGE_SIZE)
			pr_err("Buffer size is too small: %s\n", p);
		if (tracing_resize_ring_buffer(tr, v, RING_BUFFER_ALL_CPUS) < 0)
			pr_err("Failed to resize trace buffer to %s\n", p);
	}

	p = xbc_node_find_value(node, "cpumask", NULL);
	if (p && *p != '\0') {
		cpumask_var_t new_mask;

		if (alloc_cpumask_var(&new_mask, GFP_KERNEL)) {
			if (cpumask_parse(p, new_mask) < 0 ||
			    tracing_set_cpumask(tr, new_mask) < 0)
				pr_err("Failed to set new CPU mask %s\n", p);
			free_cpumask_var(new_mask);
		}
	}
}

#ifdef CONFIG_EVENT_TRACING
static void __init
trace_boot_enable_events(struct trace_array *tr, struct xbc_node *node)
{
	struct xbc_node *anode;
	char buf[MAX_BUF_LEN];
	const char *p;

	xbc_node_for_each_array_value(node, "events", anode, p) {
		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) {
			pr_err("String is too long: %s\n", p);
			continue;
		}

		if (ftrace_set_clr_event(tr, buf, 1) < 0)
			pr_err("Failed to enable event: %s\n", p);
	}
}

#ifdef CONFIG_KPROBE_EVENTS
static int __init
trace_boot_add_kprobe_event(struct xbc_node *node, const char *event)
{
	struct dynevent_cmd cmd;
	struct xbc_node *anode;
	char buf[MAX_BUF_LEN];
	const char *val;
	int ret = 0;

	xbc_node_for_each_array_value(node, "probes", anode, val) {
		kprobe_event_cmd_init(&cmd, buf, MAX_BUF_LEN);

		ret = kprobe_event_gen_cmd_start(&cmd, event, val);
		if (ret)
			break;

		ret = kprobe_event_gen_cmd_end(&cmd);
		if (ret)
			pr_err("Failed to add probe: %s\n", buf);
	}

	return ret;
}
#else
static inline int __init
trace_boot_add_kprobe_event(struct xbc_node *node, const char *event)
{
	pr_err("Kprobe event is not supported.\n");
	return -ENOTSUPP;
}
#endif

#ifdef CONFIG_HIST_TRIGGERS
static int __init
trace_boot_add_synth_event(struct xbc_node *node, const char *event)
{
	struct dynevent_cmd cmd;
	struct xbc_node *anode;
	char buf[MAX_BUF_LEN];
	const char *p;
	int ret;

	synth_event_cmd_init(&cmd, buf, MAX_BUF_LEN);

	ret = synth_event_gen_cmd_start(&cmd, event, NULL);
	if (ret)
		return ret;

	xbc_node_for_each_array_value(node, "fields", anode, p) {
		ret = synth_event_add_field_str(&cmd, p);
		if (ret)
			return ret;
	}

	ret = synth_event_gen_cmd_end(&cmd);
	if (ret < 0)
		pr_err("Failed to add synthetic event: %s\n", buf);

	return ret;
}
#else
static inline int __init
trace_boot_add_synth_event(struct xbc_node *node, const char *event)
{
	pr_err("Synthetic event is not supported.\n");
	return -ENOTSUPP;
}
#endif

static void __init
trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode,
			  struct xbc_node *enode)
{
	struct trace_event_file *file;
	struct xbc_node *anode;
	char buf[MAX_BUF_LEN];
	const char *p, *group, *event;

	group = xbc_node_get_data(gnode);
	event = xbc_node_get_data(enode);

	if (!strcmp(group, "kprobes"))
		if (trace_boot_add_kprobe_event(enode, event) < 0)
			return;
	if (!strcmp(group, "synthetic"))
		if (trace_boot_add_synth_event(enode, event) < 0)
			return;

	mutex_lock(&event_mutex);
	file = find_event_file(tr, group, event);
	if (!file) {
		pr_err("Failed to find event: %s:%s\n", group, event);
		goto out;
	}

	p = xbc_node_find_value(enode, "filter", NULL);
	if (p && *p != '\0') {
		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
			pr_err("filter string is too long: %s\n", p);
		else if (apply_event_filter(file, buf) < 0)
			pr_err("Failed to apply filter: %s\n", buf);
	}

	xbc_node_for_each_array_value(enode, "actions", anode, p) {
		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
			pr_err("action string is too long: %s\n", p);
		else if (trigger_process_regex(file, buf) < 0)
			pr_err("Failed to apply an action: %s\n", buf);
	}

	if (xbc_node_find_value(enode, "enable", NULL)) {
		if (trace_event_enable_disable(file, 1, 0) < 0)
			pr_err("Failed to enable event node: %s:%s\n",
				group, event);
	}
out:
	mutex_unlock(&event_mutex);
}

static void __init
trace_boot_init_events(struct trace_array *tr, struct xbc_node *node)
{
	struct xbc_node *gnode, *enode;

	node = xbc_node_find_child(node, "event");
	if (!node)
		return;
	/* per-event key starts with "event.GROUP.EVENT" */
	xbc_node_for_each_child(node, gnode)
		xbc_node_for_each_child(gnode, enode)
			trace_boot_init_one_event(tr, gnode, enode);
}
#else
#define trace_boot_enable_events(tr, node) do {} while (0)
#define trace_boot_init_events(tr, node) do {} while (0)
#endif

#ifdef CONFIG_DYNAMIC_FTRACE
static void __init
trace_boot_set_ftrace_filter(struct trace_array *tr, struct xbc_node *node)
{
	struct xbc_node *anode;
	const char *p;
	char *q;

	xbc_node_for_each_array_value(node, "ftrace.filters", anode, p) {
		q = kstrdup(p, GFP_KERNEL);
		if (!q)
			return;
		if (ftrace_set_filter(tr->ops, q, strlen(q), 0) < 0)
			pr_err("Failed to add %s to ftrace filter\n", p);
		else
			ftrace_filter_param = true;
		kfree(q);
	}
	xbc_node_for_each_array_value(node, "ftrace.notraces", anode, p) {
		q = kstrdup(p, GFP_KERNEL);
		if (!q)
			return;
		if (ftrace_set_notrace(tr->ops, q, strlen(q), 0) < 0)
			pr_err("Failed to add %s to ftrace filter\n", p);
		else
			ftrace_filter_param = true;
		kfree(q);
	}
}
#else
#define trace_boot_set_ftrace_filter(tr, node) do {} while (0)
#endif

static void __init
trace_boot_enable_tracer(struct trace_array *tr, struct xbc_node *node)
{
	const char *p;

	trace_boot_set_ftrace_filter(tr, node);

	p = xbc_node_find_value(node, "tracer", NULL);
	if (p && *p != '\0') {
		if (tracing_set_tracer(tr, p) < 0)
			pr_err("Failed to set given tracer: %s\n", p);
	}
}

static void __init
trace_boot_init_one_instance(struct trace_array *tr, struct xbc_node *node)
{
	trace_boot_set_instance_options(tr, node);
	trace_boot_init_events(tr, node);
	trace_boot_enable_events(tr, node);
	trace_boot_enable_tracer(tr, node);
}

static void __init
trace_boot_init_instances(struct xbc_node *node)
{
	struct xbc_node *inode;
	struct trace_array *tr;
	const char *p;

	node = xbc_node_find_child(node, "instance");
	if (!node)
		return;

	xbc_node_for_each_child(node, inode) {
		p = xbc_node_get_data(inode);
		if (!p || *p == '\0')
			continue;

		tr = trace_array_get_by_name(p);
		if (!tr) {
			pr_err("Failed to get trace instance %s\n", p);
			continue;
		}
		trace_boot_init_one_instance(tr, inode);
		trace_array_put(tr);
	}
}

static int __init trace_boot_init(void)
{
	struct xbc_node *trace_node;
	struct trace_array *tr;

	trace_node = xbc_find_node("ftrace");
	if (!trace_node)
		return 0;

	tr = top_trace_array();
	if (!tr)
		return 0;

	/* Global trace array is also one instance */
	trace_boot_init_one_instance(tr, trace_node);
	trace_boot_init_instances(trace_node);

	return 0;
}

fs_initcall(trace_boot_init);
Commit	Line	Data
9c5b9d3d MH	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* trace_boot.c
	4	* Tracing kernel boot-time
	5	*/
	6
	7	#define pr_fmt(fmt) "trace_boot: " fmt
	8
76a598ec MH	9	#include <linux/bootconfig.h>
76a598ec MH	10	#include <linux/cpumask.h>
9c5b9d3d MH	11	#include <linux/ftrace.h>
9c5b9d3d MH	12	#include <linux/init.h>
76a598ec MH	13	#include <linux/kernel.h>
	14	#include <linux/mutex.h>
	15	#include <linux/string.h>
	16	#include <linux/slab.h>
	17	#include <linux/trace.h>
	18	#include <linux/trace_events.h>
9c5b9d3d MH	19
	20	#include "trace.h"
	21
	22	#define MAX_BUF_LEN 256
	23
9c5b9d3d	24	static void __init
4f712a4d	25	trace_boot_set_instance_options(struct trace_array tr, struct xbc_node node)
9c5b9d3d MH	26	{
	27	struct xbc_node *anode;
	28	const char *p;
	29	char buf[MAX_BUF_LEN];
	30	unsigned long v = 0;
	31
	32	/* Common ftrace options */
	33	xbc_node_for_each_array_value(node, "options", anode, p) {
	34	if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) {
	35	pr_err("String is too long: %s\n", p);
	36	continue;
	37	}
	38
	39	if (trace_set_options(tr, buf) < 0)
	40	pr_err("Failed to set option: %s\n", buf);
	41	}
	42
	43	p = xbc_node_find_value(node, "trace_clock", NULL);
	44	if (p && *p != '\0') {
	45	if (tracing_set_clock(tr, p) < 0)
	46	pr_err("Failed to set trace clock: %s\n", p);
	47	}
	48
	49	p = xbc_node_find_value(node, "buffer_size", NULL);
	50	if (p && *p != '\0') {
	51	v = memparse(p, NULL);
	52	if (v < PAGE_SIZE)
	53	pr_err("Buffer size is too small: %s\n", p);
	54	if (tracing_resize_ring_buffer(tr, v, RING_BUFFER_ALL_CPUS) < 0)
	55	pr_err("Failed to resize trace buffer to %s\n", p);
	56	}
9d15dbbd MH	57
	58	p = xbc_node_find_value(node, "cpumask", NULL);
	59	if (p && *p != '\0') {
	60	cpumask_var_t new_mask;
	61
	62	if (alloc_cpumask_var(&new_mask, GFP_KERNEL)) {
	63	if (cpumask_parse(p, new_mask) < 0 \|\|
	64	tracing_set_cpumask(tr, new_mask) < 0)
	65	pr_err("Failed to set new CPU mask %s\n", p);
	66	free_cpumask_var(new_mask);
	67	}
	68	}
9c5b9d3d MH	69	}
	70
	71	#ifdef CONFIG_EVENT_TRACING
9c5b9d3d MH	72	static void __init
	73	trace_boot_enable_events(struct trace_array tr, struct xbc_node node)
	74	{
	75	struct xbc_node *anode;
	76	char buf[MAX_BUF_LEN];
	77	const char *p;
	78
	79	xbc_node_for_each_array_value(node, "events", anode, p) {
	80	if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) {
	81	pr_err("String is too long: %s\n", p);
	82	continue;
	83	}
	84
	85	if (ftrace_set_clr_event(tr, buf, 1) < 0)
	86	pr_err("Failed to enable event: %s\n", p);
	87	}
	88	}
81a59555	89
4d655281	90	#ifdef CONFIG_KPROBE_EVENTS
4d655281 MH	91	static int __init
	92	trace_boot_add_kprobe_event(struct xbc_node node, const char event)
	93	{
29a15481	94	struct dynevent_cmd cmd;
4d655281 MH	95	struct xbc_node *anode;
	96	char buf[MAX_BUF_LEN];
	97	const char *val;
da0f1f41	98	int ret = 0;
4d655281	99
da0f1f41 MH	100	xbc_node_for_each_array_value(node, "probes", anode, val) {
da0f1f41 MH	101	kprobe_event_cmd_init(&cmd, buf, MAX_BUF_LEN);
29a15481	102
da0f1f41 MH	103	ret = kprobe_event_gen_cmd_start(&cmd, event, val);
	104	if (ret)
	105	break;
4d655281	106
da0f1f41	107	ret = kprobe_event_gen_cmd_end(&cmd);
29a15481	108	if (ret)
da0f1f41	109	pr_err("Failed to add probe: %s\n", buf);
4d655281 MH	110	}
4d655281 MH	111
29a15481	112	return ret;
4d655281 MH	113	}
	114	#else
	115	static inline int __init
	116	trace_boot_add_kprobe_event(struct xbc_node node, const char event)
	117	{
	118	pr_err("Kprobe event is not supported.\n");
	119	return -ENOTSUPP;
	120	}
	121	#endif
	122
3fbe2d6e	123	#ifdef CONFIG_HIST_TRIGGERS
3fbe2d6e MH	124	static int __init
	125	trace_boot_add_synth_event(struct xbc_node node, const char event)
	126	{
fdeb1aca	127	struct dynevent_cmd cmd;
3fbe2d6e	128	struct xbc_node *anode;
fdeb1aca	129	char buf[MAX_BUF_LEN];
3fbe2d6e	130	const char *p;
fdeb1aca	131	int ret;
3fbe2d6e	132
fdeb1aca TZ	133	synth_event_cmd_init(&cmd, buf, MAX_BUF_LEN);
	134
	135	ret = synth_event_gen_cmd_start(&cmd, event, NULL);
	136	if (ret)
	137	return ret;
3fbe2d6e MH	138
3fbe2d6e MH	139	xbc_node_for_each_array_value(node, "fields", anode, p) {
fdeb1aca TZ	140	ret = synth_event_add_field_str(&cmd, p);
	141	if (ret)
	142	return ret;
3fbe2d6e MH	143	}
3fbe2d6e MH	144
fdeb1aca	145	ret = synth_event_gen_cmd_end(&cmd);
3fbe2d6e MH	146	if (ret < 0)
	147	pr_err("Failed to add synthetic event: %s\n", buf);
	148
3fbe2d6e MH	149	return ret;
	150	}
	151	#else
	152	static inline int __init
	153	trace_boot_add_synth_event(struct xbc_node node, const char event)
	154	{
	155	pr_err("Synthetic event is not supported.\n");
	156	return -ENOTSUPP;
	157	}
	158	#endif
	159
81a59555 MH	160	static void __init
	161	trace_boot_init_one_event(struct trace_array tr, struct xbc_node gnode,
	162	struct xbc_node *enode)
	163	{
	164	struct trace_event_file *file;
	165	struct xbc_node *anode;
	166	char buf[MAX_BUF_LEN];
	167	const char p, group, *event;
	168
	169	group = xbc_node_get_data(gnode);
	170	event = xbc_node_get_data(enode);
	171
4d655281 MH	172	if (!strcmp(group, "kprobes"))
	173	if (trace_boot_add_kprobe_event(enode, event) < 0)
	174	return;
3fbe2d6e MH	175	if (!strcmp(group, "synthetic"))
	176	if (trace_boot_add_synth_event(enode, event) < 0)
	177	return;
4d655281	178
81a59555 MH	179	mutex_lock(&event_mutex);
	180	file = find_event_file(tr, group, event);
	181	if (!file) {
	182	pr_err("Failed to find event: %s:%s\n", group, event);
	183	goto out;
	184	}
	185
	186	p = xbc_node_find_value(enode, "filter", NULL);
	187	if (p && *p != '\0') {
	188	if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
	189	pr_err("filter string is too long: %s\n", p);
	190	else if (apply_event_filter(file, buf) < 0)
	191	pr_err("Failed to apply filter: %s\n", buf);
	192	}
	193
	194	xbc_node_for_each_array_value(enode, "actions", anode, p) {
	195	if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
	196	pr_err("action string is too long: %s\n", p);
	197	else if (trigger_process_regex(file, buf) < 0)
	198	pr_err("Failed to apply an action: %s\n", buf);
	199	}
	200
	201	if (xbc_node_find_value(enode, "enable", NULL)) {
	202	if (trace_event_enable_disable(file, 1, 0) < 0)
	203	pr_err("Failed to enable event node: %s:%s\n",
	204	group, event);
	205	}
	206	out:
	207	mutex_unlock(&event_mutex);
	208	}
	209
	210	static void __init
	211	trace_boot_init_events(struct trace_array tr, struct xbc_node node)
	212	{
	213	struct xbc_node gnode, enode;
	214
	215	node = xbc_node_find_child(node, "event");
	216	if (!node)
	217	return;
	218	/* per-event key starts with "event.GROUP.EVENT" */
	219	xbc_node_for_each_child(node, gnode)
	220	xbc_node_for_each_child(gnode, enode)
	221	trace_boot_init_one_event(tr, gnode, enode);
	222	}
9c5b9d3d MH	223	#else
9c5b9d3d MH	224	#define trace_boot_enable_events(tr, node) do {} while (0)
81a59555	225	#define trace_boot_init_events(tr, node) do {} while (0)
9c5b9d3d MH	226	#endif
9c5b9d3d MH	227
fe1efe92	228	#ifdef CONFIG_DYNAMIC_FTRACE
fe1efe92 MH	229	static void __init
	230	trace_boot_set_ftrace_filter(struct trace_array tr, struct xbc_node node)
	231	{
	232	struct xbc_node *anode;
	233	const char *p;
	234	char *q;
	235
	236	xbc_node_for_each_array_value(node, "ftrace.filters", anode, p) {
	237	q = kstrdup(p, GFP_KERNEL);
	238	if (!q)
	239	return;
	240	if (ftrace_set_filter(tr->ops, q, strlen(q), 0) < 0)
	241	pr_err("Failed to add %s to ftrace filter\n", p);
	242	else
	243	ftrace_filter_param = true;
	244	kfree(q);
	245	}
	246	xbc_node_for_each_array_value(node, "ftrace.notraces", anode, p) {
	247	q = kstrdup(p, GFP_KERNEL);
	248	if (!q)
	249	return;
	250	if (ftrace_set_notrace(tr->ops, q, strlen(q), 0) < 0)
	251	pr_err("Failed to add %s to ftrace filter\n", p);
	252	else
	253	ftrace_filter_param = true;
	254	kfree(q);
	255	}
	256	}
	257	#else
	258	#define trace_boot_set_ftrace_filter(tr, node) do {} while (0)
	259	#endif
	260
9c5b9d3d MH	261	static void __init
	262	trace_boot_enable_tracer(struct trace_array tr, struct xbc_node node)
	263	{
	264	const char *p;
	265
fe1efe92 MH	266	trace_boot_set_ftrace_filter(tr, node);
fe1efe92 MH	267
9c5b9d3d MH	268	p = xbc_node_find_value(node, "tracer", NULL);
	269	if (p && *p != '\0') {
	270	if (tracing_set_tracer(tr, p) < 0)
	271	pr_err("Failed to set given tracer: %s\n", p);
	272	}
	273	}
	274
4f712a4d MH	275	static void __init
	276	trace_boot_init_one_instance(struct trace_array tr, struct xbc_node node)
	277	{
	278	trace_boot_set_instance_options(tr, node);
	279	trace_boot_init_events(tr, node);
	280	trace_boot_enable_events(tr, node);
	281	trace_boot_enable_tracer(tr, node);
	282	}
	283
	284	static void __init
	285	trace_boot_init_instances(struct xbc_node *node)
	286	{
	287	struct xbc_node *inode;
	288	struct trace_array *tr;
	289	const char *p;
	290
	291	node = xbc_node_find_child(node, "instance");
	292	if (!node)
	293	return;
	294
	295	xbc_node_for_each_child(node, inode) {
	296	p = xbc_node_get_data(inode);
	297	if (!p \|\| *p == '\0')
	298	continue;
	299
	300	tr = trace_array_get_by_name(p);
532f49a6	301	if (!tr) {
4f712a4d MH	302	pr_err("Failed to get trace instance %s\n", p);
	303	continue;
	304	}
	305	trace_boot_init_one_instance(tr, inode);
28394da2	306	trace_array_put(tr);
4f712a4d MH	307	}
	308	}
	309
9c5b9d3d MH	310	static int __init trace_boot_init(void)
	311	{
	312	struct xbc_node *trace_node;
	313	struct trace_array *tr;
	314
	315	trace_node = xbc_find_node("ftrace");
	316	if (!trace_node)
	317	return 0;
	318
	319	tr = top_trace_array();
	320	if (!tr)
	321	return 0;
	322
4f712a4d MH	323	/* Global trace array is also one instance */
	324	trace_boot_init_one_instance(tr, trace_node);
	325	trace_boot_init_instances(trace_node);
9c5b9d3d MH	326
	327	return 0;
	328	}
	329
	330	fs_initcall(trace_boot_init);