[linux-block.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, "tracing_on", NULL);
	if (p && *p != '\0') {
		if (kstrtoul(p, 10, &v))
			pr_err("Failed to set tracing on: %s\n", p);
		if (v)
			tracer_tracing_on(tr);
		else
			tracer_tracing_off(tr);
	}

	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) {
			pr_err("Failed to generate probe: %s\n", buf);
			break;
		}

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

	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_SYNTH_EVENTS
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);
	}

	/* Since tracer can free snapshot buffer, allocate snapshot here.*/
	if (xbc_node_find_value(node, "alloc_snapshot", NULL)) {
		if (tracing_alloc_snapshot_instance(tr) < 0)
			pr_err("Failed to allocate snapshot buffer\n");
	}
}

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);

	disable_tracing_selftest("running boot-time tracing");

	return 0;
}
/*
 * Start tracing at the end of core-initcall, so that it starts tracing
 * from the beginning of postcore_initcall.
 */
core_initcall_sync(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
8490db06 MH	43	p = xbc_node_find_value(node, "tracing_on", NULL);
	44	if (p && *p != '\0') {
	45	if (kstrtoul(p, 10, &v))
	46	pr_err("Failed to set tracing on: %s\n", p);
	47	if (v)
	48	tracer_tracing_on(tr);
	49	else
	50	tracer_tracing_off(tr);
	51	}
	52
9c5b9d3d MH	53	p = xbc_node_find_value(node, "trace_clock", NULL);
	54	if (p && *p != '\0') {
	55	if (tracing_set_clock(tr, p) < 0)
	56	pr_err("Failed to set trace clock: %s\n", p);
	57	}
	58
	59	p = xbc_node_find_value(node, "buffer_size", NULL);
	60	if (p && *p != '\0') {
	61	v = memparse(p, NULL);
	62	if (v < PAGE_SIZE)
	63	pr_err("Buffer size is too small: %s\n", p);
	64	if (tracing_resize_ring_buffer(tr, v, RING_BUFFER_ALL_CPUS) < 0)
	65	pr_err("Failed to resize trace buffer to %s\n", p);
	66	}
9d15dbbd MH	67
	68	p = xbc_node_find_value(node, "cpumask", NULL);
	69	if (p && *p != '\0') {
	70	cpumask_var_t new_mask;
	71
	72	if (alloc_cpumask_var(&new_mask, GFP_KERNEL)) {
	73	if (cpumask_parse(p, new_mask) < 0 \|\|
	74	tracing_set_cpumask(tr, new_mask) < 0)
	75	pr_err("Failed to set new CPU mask %s\n", p);
	76	free_cpumask_var(new_mask);
	77	}
	78	}
9c5b9d3d MH	79	}
	80
	81	#ifdef CONFIG_EVENT_TRACING
9c5b9d3d MH	82	static void __init
	83	trace_boot_enable_events(struct trace_array tr, struct xbc_node node)
	84	{
	85	struct xbc_node *anode;
	86	char buf[MAX_BUF_LEN];
	87	const char *p;
	88
	89	xbc_node_for_each_array_value(node, "events", anode, p) {
	90	if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) {
	91	pr_err("String is too long: %s\n", p);
	92	continue;
	93	}
	94
	95	if (ftrace_set_clr_event(tr, buf, 1) < 0)
	96	pr_err("Failed to enable event: %s\n", p);
	97	}
	98	}
81a59555	99
4d655281	100	#ifdef CONFIG_KPROBE_EVENTS
4d655281 MH	101	static int __init
	102	trace_boot_add_kprobe_event(struct xbc_node node, const char event)
	103	{
29a15481	104	struct dynevent_cmd cmd;
4d655281 MH	105	struct xbc_node *anode;
	106	char buf[MAX_BUF_LEN];
	107	const char *val;
da0f1f41	108	int ret = 0;
4d655281	109
da0f1f41 MH	110	xbc_node_for_each_array_value(node, "probes", anode, val) {
da0f1f41 MH	111	kprobe_event_cmd_init(&cmd, buf, MAX_BUF_LEN);
29a15481	112
da0f1f41	113	ret = kprobe_event_gen_cmd_start(&cmd, event, val);
20dc3847 SO	114	if (ret) {
20dc3847 SO	115	pr_err("Failed to generate probe: %s\n", buf);
da0f1f41	116	break;
20dc3847	117	}
4d655281	118
da0f1f41	119	ret = kprobe_event_gen_cmd_end(&cmd);
20dc3847	120	if (ret) {
da0f1f41	121	pr_err("Failed to add probe: %s\n", buf);
20dc3847 SO	122	break;
20dc3847 SO	123	}
4d655281 MH	124	}
4d655281 MH	125
29a15481	126	return ret;
4d655281 MH	127	}
	128	#else
	129	static inline int __init
	130	trace_boot_add_kprobe_event(struct xbc_node node, const char event)
	131	{
	132	pr_err("Kprobe event is not supported.\n");
	133	return -ENOTSUPP;
	134	}
	135	#endif
	136
6c95503c	137	#ifdef CONFIG_SYNTH_EVENTS
3fbe2d6e MH	138	static int __init
	139	trace_boot_add_synth_event(struct xbc_node node, const char event)
	140	{
fdeb1aca	141	struct dynevent_cmd cmd;
3fbe2d6e	142	struct xbc_node *anode;
fdeb1aca	143	char buf[MAX_BUF_LEN];
3fbe2d6e	144	const char *p;
fdeb1aca	145	int ret;
3fbe2d6e	146
fdeb1aca TZ	147	synth_event_cmd_init(&cmd, buf, MAX_BUF_LEN);
	148
	149	ret = synth_event_gen_cmd_start(&cmd, event, NULL);
	150	if (ret)
	151	return ret;
3fbe2d6e MH	152
3fbe2d6e MH	153	xbc_node_for_each_array_value(node, "fields", anode, p) {
fdeb1aca TZ	154	ret = synth_event_add_field_str(&cmd, p);
	155	if (ret)
	156	return ret;
3fbe2d6e MH	157	}
3fbe2d6e MH	158
fdeb1aca	159	ret = synth_event_gen_cmd_end(&cmd);
3fbe2d6e MH	160	if (ret < 0)
	161	pr_err("Failed to add synthetic event: %s\n", buf);
	162
3fbe2d6e MH	163	return ret;
	164	}
	165	#else
	166	static inline int __init
	167	trace_boot_add_synth_event(struct xbc_node node, const char event)
	168	{
	169	pr_err("Synthetic event is not supported.\n");
	170	return -ENOTSUPP;
	171	}
	172	#endif
	173
81a59555 MH	174	static void __init
	175	trace_boot_init_one_event(struct trace_array tr, struct xbc_node gnode,
	176	struct xbc_node *enode)
	177	{
	178	struct trace_event_file *file;
	179	struct xbc_node *anode;
	180	char buf[MAX_BUF_LEN];
	181	const char p, group, *event;
	182
	183	group = xbc_node_get_data(gnode);
	184	event = xbc_node_get_data(enode);
	185
4d655281 MH	186	if (!strcmp(group, "kprobes"))
	187	if (trace_boot_add_kprobe_event(enode, event) < 0)
	188	return;
3fbe2d6e MH	189	if (!strcmp(group, "synthetic"))
	190	if (trace_boot_add_synth_event(enode, event) < 0)
	191	return;
4d655281	192
81a59555 MH	193	mutex_lock(&event_mutex);
	194	file = find_event_file(tr, group, event);
	195	if (!file) {
	196	pr_err("Failed to find event: %s:%s\n", group, event);
	197	goto out;
	198	}
	199
	200	p = xbc_node_find_value(enode, "filter", NULL);
	201	if (p && *p != '\0') {
	202	if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
	203	pr_err("filter string is too long: %s\n", p);
	204	else if (apply_event_filter(file, buf) < 0)
	205	pr_err("Failed to apply filter: %s\n", buf);
	206	}
	207
	208	xbc_node_for_each_array_value(enode, "actions", anode, p) {
	209	if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
	210	pr_err("action string is too long: %s\n", p);
	211	else if (trigger_process_regex(file, buf) < 0)
	212	pr_err("Failed to apply an action: %s\n", buf);
	213	}
	214
	215	if (xbc_node_find_value(enode, "enable", NULL)) {
	216	if (trace_event_enable_disable(file, 1, 0) < 0)
	217	pr_err("Failed to enable event node: %s:%s\n",
	218	group, event);
	219	}
	220	out:
	221	mutex_unlock(&event_mutex);
	222	}
	223
	224	static void __init
	225	trace_boot_init_events(struct trace_array tr, struct xbc_node node)
	226	{
	227	struct xbc_node gnode, enode;
	228
	229	node = xbc_node_find_child(node, "event");
	230	if (!node)
	231	return;
	232	/* per-event key starts with "event.GROUP.EVENT" */
	233	xbc_node_for_each_child(node, gnode)
	234	xbc_node_for_each_child(gnode, enode)
	235	trace_boot_init_one_event(tr, gnode, enode);
	236	}
9c5b9d3d MH	237	#else
9c5b9d3d MH	238	#define trace_boot_enable_events(tr, node) do {} while (0)
81a59555	239	#define trace_boot_init_events(tr, node) do {} while (0)
9c5b9d3d MH	240	#endif
9c5b9d3d MH	241
fe1efe92	242	#ifdef CONFIG_DYNAMIC_FTRACE
fe1efe92 MH	243	static void __init
	244	trace_boot_set_ftrace_filter(struct trace_array tr, struct xbc_node node)
	245	{
	246	struct xbc_node *anode;
	247	const char *p;
	248	char *q;
	249
	250	xbc_node_for_each_array_value(node, "ftrace.filters", anode, p) {
	251	q = kstrdup(p, GFP_KERNEL);
	252	if (!q)
	253	return;
	254	if (ftrace_set_filter(tr->ops, q, strlen(q), 0) < 0)
	255	pr_err("Failed to add %s to ftrace filter\n", p);
	256	else
	257	ftrace_filter_param = true;
	258	kfree(q);
	259	}
	260	xbc_node_for_each_array_value(node, "ftrace.notraces", anode, p) {
	261	q = kstrdup(p, GFP_KERNEL);
	262	if (!q)
	263	return;
	264	if (ftrace_set_notrace(tr->ops, q, strlen(q), 0) < 0)
	265	pr_err("Failed to add %s to ftrace filter\n", p);
	266	else
	267	ftrace_filter_param = true;
	268	kfree(q);
	269	}
	270	}
	271	#else
	272	#define trace_boot_set_ftrace_filter(tr, node) do {} while (0)
	273	#endif
	274
9c5b9d3d MH	275	static void __init
	276	trace_boot_enable_tracer(struct trace_array tr, struct xbc_node node)
	277	{
	278	const char *p;
	279
fe1efe92 MH	280	trace_boot_set_ftrace_filter(tr, node);
fe1efe92 MH	281
9c5b9d3d MH	282	p = xbc_node_find_value(node, "tracer", NULL);
	283	if (p && *p != '\0') {
	284	if (tracing_set_tracer(tr, p) < 0)
	285	pr_err("Failed to set given tracer: %s\n", p);
	286	}
c1634097 MH	287
	288	/* Since tracer can free snapshot buffer, allocate snapshot here.*/
	289	if (xbc_node_find_value(node, "alloc_snapshot", NULL)) {
	290	if (tracing_alloc_snapshot_instance(tr) < 0)
	291	pr_err("Failed to allocate snapshot buffer\n");
	292	}
9c5b9d3d MH	293	}
9c5b9d3d MH	294
4f712a4d MH	295	static void __init
	296	trace_boot_init_one_instance(struct trace_array tr, struct xbc_node node)
	297	{
	298	trace_boot_set_instance_options(tr, node);
	299	trace_boot_init_events(tr, node);
	300	trace_boot_enable_events(tr, node);
	301	trace_boot_enable_tracer(tr, node);
	302	}
	303
	304	static void __init
	305	trace_boot_init_instances(struct xbc_node *node)
	306	{
	307	struct xbc_node *inode;
	308	struct trace_array *tr;
	309	const char *p;
	310
	311	node = xbc_node_find_child(node, "instance");
	312	if (!node)
	313	return;
	314
	315	xbc_node_for_each_child(node, inode) {
	316	p = xbc_node_get_data(inode);
	317	if (!p \|\| *p == '\0')
	318	continue;
	319
	320	tr = trace_array_get_by_name(p);
532f49a6	321	if (!tr) {
4f712a4d MH	322	pr_err("Failed to get trace instance %s\n", p);
	323	continue;
	324	}
	325	trace_boot_init_one_instance(tr, inode);
28394da2	326	trace_array_put(tr);
4f712a4d MH	327	}
	328	}
	329
9c5b9d3d MH	330	static int __init trace_boot_init(void)
	331	{
	332	struct xbc_node *trace_node;
	333	struct trace_array *tr;
	334
	335	trace_node = xbc_find_node("ftrace");
	336	if (!trace_node)
	337	return 0;
	338
	339	tr = top_trace_array();
	340	if (!tr)
	341	return 0;
	342
4f712a4d MH	343	/* Global trace array is also one instance */
	344	trace_boot_init_one_instance(tr, trace_node);
	345	trace_boot_init_instances(trace_node);
9c5b9d3d	346
60efe21e MH	347	disable_tracing_selftest("running boot-time tracing");
60efe21e MH	348
9c5b9d3d MH	349	return 0;
9c5b9d3d MH	350	}
ba0fbfbb MH	351	/*
	352	* Start tracing at the end of core-initcall, so that it starts tracing
	353	* from the beginning of postcore_initcall.
	354	*/
	355	core_initcall_sync(trace_boot_init);