[mirror_ubuntu-focal-kernel.git] / Documentation / perf_counter / builtin-stat.c

/*
 * builtin-stat.c
 *
 * Builtin stat command: Give a precise performance counters summary
 * overview about any workload, CPU or specific PID.
 *
 * Sample output:

   $ perf stat ~/hackbench 10
   Time: 0.104

    Performance counter stats for '/home/mingo/hackbench':

       1255.538611  task clock ticks     #      10.143 CPU utilization factor
             54011  context switches     #       0.043 M/sec
               385  CPU migrations       #       0.000 M/sec
             17755  pagefaults           #       0.014 M/sec
        3808323185  CPU cycles           #    3033.219 M/sec
        1575111190  instructions         #    1254.530 M/sec
          17367895  cache references     #      13.833 M/sec
           7674421  cache misses         #       6.112 M/sec

    Wall-clock time elapsed:   123.786620 msecs

 *
 * Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
 *
 * Improvements and fixes by:
 *
 *   Arjan van de Ven <arjan@linux.intel.com>
 *   Yanmin Zhang <yanmin.zhang@intel.com>
 *   Wu Fengguang <fengguang.wu@intel.com>
 *   Mike Galbraith <efault@gmx.de>
 *   Paul Mackerras <paulus@samba.org>
 *
 * Released under the GPL v2. (and only v2, not any later version)
 */

#include "perf.h"
#include "builtin.h"
#include "util/util.h"
#include "util/parse-options.h"
#include "util/parse-events.h"

#include <sys/prctl.h>

static int			system_wide			=  0;
static int			inherit				=  1;

static __u64			default_event_id[MAX_COUNTERS]	= {
	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK),
	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CONTEXT_SWITCHES),
	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_MIGRATIONS),
	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS),

	EID(PERF_TYPE_HARDWARE, PERF_COUNT_CPU_CYCLES),
	EID(PERF_TYPE_HARDWARE, PERF_COUNT_INSTRUCTIONS),
	EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_REFERENCES),
	EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_MISSES),
};

static int			default_interval = 100000;
static int			event_count[MAX_COUNTERS];
static int			fd[MAX_NR_CPUS][MAX_COUNTERS];

static int			target_pid			= -1;
static int			nr_cpus				=  0;
static unsigned int		page_size;

static int			scale				=  1;

static const unsigned int default_count[] = {
	1000000,
	1000000,
	  10000,
	  10000,
	1000000,
	  10000,
};

static __u64			event_res[MAX_COUNTERS][3];
static __u64			event_scaled[MAX_COUNTERS];

static __u64			runtime_nsecs;
static __u64			walltime_nsecs;

static void create_perfstat_counter(int counter)
{
	struct perf_counter_attr attr;

	memset(&attr, 0, sizeof(attr));
	attr.config		= event_id[counter];
	attr.sample_type	= 0;
	attr.exclude_kernel = event_mask[counter] & EVENT_MASK_KERNEL;
	attr.exclude_user   = event_mask[counter] & EVENT_MASK_USER;

	if (scale)
		attr.read_format	= PERF_FORMAT_TOTAL_TIME_ENABLED |
					  PERF_FORMAT_TOTAL_TIME_RUNNING;

	if (system_wide) {
		int cpu;
		for (cpu = 0; cpu < nr_cpus; cpu ++) {
			fd[cpu][counter] = sys_perf_counter_open(&attr, -1, cpu, -1, 0);
			if (fd[cpu][counter] < 0) {
				printf("perfstat error: syscall returned with %d (%s)\n",
						fd[cpu][counter], strerror(errno));
				exit(-1);
			}
		}
	} else {
		attr.inherit	= inherit;
		attr.disabled	= 1;

		fd[0][counter] = sys_perf_counter_open(&attr, 0, -1, -1, 0);
		if (fd[0][counter] < 0) {
			printf("perfstat error: syscall returned with %d (%s)\n",
					fd[0][counter], strerror(errno));
			exit(-1);
		}
	}
}

/*
 * Does the counter have nsecs as a unit?
 */
static inline int nsec_counter(int counter)
{
	if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_CLOCK))
		return 1;
	if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK))
		return 1;

	return 0;
}

/*
 * Read out the results of a single counter:
 */
static void read_counter(int counter)
{
	__u64 *count, single_count[3];
	ssize_t res;
	int cpu, nv;
	int scaled;

	count = event_res[counter];

	count[0] = count[1] = count[2] = 0;

	nv = scale ? 3 : 1;
	for (cpu = 0; cpu < nr_cpus; cpu ++) {
		res = read(fd[cpu][counter], single_count, nv * sizeof(__u64));
		assert(res == nv * sizeof(__u64));

		count[0] += single_count[0];
		if (scale) {
			count[1] += single_count[1];
			count[2] += single_count[2];
		}
	}

	scaled = 0;
	if (scale) {
		if (count[2] == 0) {
			event_scaled[counter] = -1;
			count[0] = 0;
			return;
		}

		if (count[2] < count[1]) {
			event_scaled[counter] = 1;
			count[0] = (unsigned long long)
				((double)count[0] * count[1] / count[2] + 0.5);
		}
	}
	/*
	 * Save the full runtime - to allow normalization during printout:
	 */
	if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK))
		runtime_nsecs = count[0];
}

/*
 * Print out the results of a single counter:
 */
static void print_counter(int counter)
{
	__u64 *count;
	int scaled;

	count = event_res[counter];
	scaled = event_scaled[counter];

	if (scaled == -1) {
		fprintf(stderr, " %14s  %-20s\n",
			"<not counted>", event_name(counter));
		return;
	}

	if (nsec_counter(counter)) {
		double msecs = (double)count[0] / 1000000;

		fprintf(stderr, " %14.6f  %-20s",
			msecs, event_name(counter));
		if (event_id[counter] ==
				EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK)) {

			fprintf(stderr, " # %11.3f CPU utilization factor",
				(double)count[0] / (double)walltime_nsecs);
		}
	} else {
		fprintf(stderr, " %14Ld  %-20s",
			count[0], event_name(counter));
		if (runtime_nsecs)
			fprintf(stderr, " # %11.3f M/sec",
				(double)count[0]/runtime_nsecs*1000.0);
	}
	if (scaled)
		fprintf(stderr, "  (scaled from %.2f%%)",
			(double) count[2] / count[1] * 100);
	fprintf(stderr, "\n");
}

static int do_perfstat(int argc, const char **argv)
{
	unsigned long long t0, t1;
	int counter;
	int status;
	int pid;
	int i;

	if (!system_wide)
		nr_cpus = 1;

	for (counter = 0; counter < nr_counters; counter++)
		create_perfstat_counter(counter);

	/*
	 * Enable counters and exec the command:
	 */
	t0 = rdclock();
	prctl(PR_TASK_PERF_COUNTERS_ENABLE);

	if ((pid = fork()) < 0)
		perror("failed to fork");

	if (!pid) {
		if (execvp(argv[0], (char **)argv)) {
			perror(argv[0]);
			exit(-1);
		}
	}

	while (wait(&status) >= 0)
		;

	prctl(PR_TASK_PERF_COUNTERS_DISABLE);
	t1 = rdclock();

	walltime_nsecs = t1 - t0;

	fflush(stdout);

	fprintf(stderr, "\n");
	fprintf(stderr, " Performance counter stats for \'%s", argv[0]);

	for (i = 1; i < argc; i++)
		fprintf(stderr, " %s", argv[i]);

	fprintf(stderr, "\':\n");
	fprintf(stderr, "\n");

	for (counter = 0; counter < nr_counters; counter++)
		read_counter(counter);

	for (counter = 0; counter < nr_counters; counter++)
		print_counter(counter);


	fprintf(stderr, "\n");
	fprintf(stderr, " Wall-clock time elapsed: %12.6f msecs\n",
			(double)(t1-t0)/1e6);
	fprintf(stderr, "\n");

	return 0;
}

static void skip_signal(int signo)
{
}

static const char * const stat_usage[] = {
	"perf stat [<options>] <command>",
	NULL
};

static char events_help_msg[EVENTS_HELP_MAX];

static const struct option options[] = {
	OPT_CALLBACK('e', "event", NULL, "event",
		     events_help_msg, parse_events),
	OPT_INTEGER('c', "count", &default_interval,
		    "event period to sample"),
	OPT_BOOLEAN('i', "inherit", &inherit,
		    "child tasks inherit counters"),
	OPT_INTEGER('p', "pid", &target_pid,
		    "stat events on existing pid"),
	OPT_BOOLEAN('a', "all-cpus", &system_wide,
			    "system-wide collection from all CPUs"),
	OPT_BOOLEAN('l', "scale", &scale,
			    "scale/normalize counters"),
	OPT_END()
};

int cmd_stat(int argc, const char **argv, const char *prefix)
{
	int counter;

	page_size = sysconf(_SC_PAGE_SIZE);

	create_events_help(events_help_msg);
	memcpy(event_id, default_event_id, sizeof(default_event_id));

	argc = parse_options(argc, argv, options, stat_usage, 0);
	if (!argc)
		usage_with_options(stat_usage, options);

	if (!nr_counters) {
		nr_counters = 8;
	}

	for (counter = 0; counter < nr_counters; counter++) {
		if (event_count[counter])
			continue;

		event_count[counter] = default_interval;
	}
	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
	assert(nr_cpus <= MAX_NR_CPUS);
	assert(nr_cpus >= 0);

	/*
	 * We dont want to block the signals - that would cause
	 * child tasks to inherit that and Ctrl-C would not work.
	 * What we want is for Ctrl-C to work in the exec()-ed
	 * task, but being ignored by perf stat itself:
	 */
	signal(SIGINT,  skip_signal);
	signal(SIGALRM, skip_signal);
	signal(SIGABRT, skip_signal);

	return do_perfstat(argc, argv);
}
Commit	Line	Data
ddcacfa0	1	/*
bf9e1876 IM	2	* builtin-stat.c
	3	*
	4	* Builtin stat command: Give a precise performance counters summary
	5	* overview about any workload, CPU or specific PID.
	6	*
	7	* Sample output:
ddcacfa0	8
bf9e1876 IM	9	$ perf stat ~/hackbench 10
bf9e1876 IM	10	Time: 0.104
ddcacfa0	11
bf9e1876	12	Performance counter stats for '/home/mingo/hackbench':
ddcacfa0	13
bf9e1876 IM	14	1255.538611 task clock ticks # 10.143 CPU utilization factor
	15	54011 context switches # 0.043 M/sec
	16	385 CPU migrations # 0.000 M/sec
	17	17755 pagefaults # 0.014 M/sec
	18	3808323185 CPU cycles # 3033.219 M/sec
	19	1575111190 instructions # 1254.530 M/sec
	20	17367895 cache references # 13.833 M/sec
	21	7674421 cache misses # 6.112 M/sec
ddcacfa0	22
bf9e1876	23	Wall-clock time elapsed: 123.786620 msecs
ddcacfa0	24
5242519b IM	25	*
	26	* Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
	27	*
	28	* Improvements and fixes by:
	29	*
	30	* Arjan van de Ven <arjan@linux.intel.com>
	31	* Yanmin Zhang <yanmin.zhang@intel.com>
	32	* Wu Fengguang <fengguang.wu@intel.com>
	33	* Mike Galbraith <efault@gmx.de>
	34	* Paul Mackerras <paulus@samba.org>
	35	*
	36	* Released under the GPL v2. (and only v2, not any later version)
ddcacfa0 IM	37	*/
ddcacfa0 IM	38
1a482f38	39	#include "perf.h"
16f762a2	40	#include "builtin.h"
148be2c1	41	#include "util/util.h"
5242519b IM	42	#include "util/parse-options.h"
5242519b IM	43	#include "util/parse-events.h"
ddcacfa0	44
ddcacfa0	45	#include <sys/prctl.h>
16c8a109	46
ddcacfa0	47	static int system_wide = 0;
5242519b	48	static int inherit = 1;
ddcacfa0	49
5242519b	50	static __u64 default_event_id[MAX_COUNTERS] = {
ddcacfa0 IM	51	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK),
	52	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CONTEXT_SWITCHES),
	53	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_MIGRATIONS),
	54	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS),
	55
	56	EID(PERF_TYPE_HARDWARE, PERF_COUNT_CPU_CYCLES),
	57	EID(PERF_TYPE_HARDWARE, PERF_COUNT_INSTRUCTIONS),
	58	EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_REFERENCES),
	59	EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_MISSES),
	60	};
5242519b	61
ddcacfa0 IM	62	static int default_interval = 100000;
	63	static int event_count[MAX_COUNTERS];
	64	static int fd[MAX_NR_CPUS][MAX_COUNTERS];
	65
5242519b	66	static int target_pid = -1;
ddcacfa0	67	static int nr_cpus = 0;
ddcacfa0 IM	68	static unsigned int page_size;
ddcacfa0 IM	69
66cf7829	70	static int scale = 1;
ddcacfa0 IM	71
	72	static const unsigned int default_count[] = {
	73	1000000,
	74	1000000,
	75	10000,
	76	10000,
	77	1000000,
	78	10000,
	79	};
	80
2996f5dd IM	81	static __u64 event_res[MAX_COUNTERS][3];
	82	static __u64 event_scaled[MAX_COUNTERS];
	83
be1ac0d8	84	static __u64 runtime_nsecs;
d7c29318	85	static __u64 walltime_nsecs;
be1ac0d8	86
ddcacfa0 IM	87	static void create_perfstat_counter(int counter)
ddcacfa0 IM	88	{
c70975bc	89	struct perf_counter_attr attr;
ddcacfa0	90
c70975bc PZ	91	memset(&attr, 0, sizeof(attr));
	92	attr.config = event_id[counter];
	93	attr.sample_type = 0;
	94	attr.exclude_kernel = event_mask[counter] & EVENT_MASK_KERNEL;
	95	attr.exclude_user = event_mask[counter] & EVENT_MASK_USER;
16c8a109	96
ddcacfa0	97	if (scale)
c70975bc	98	attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED \|
ddcacfa0 IM	99	PERF_FORMAT_TOTAL_TIME_RUNNING;
	100
	101	if (system_wide) {
	102	int cpu;
	103	for (cpu = 0; cpu < nr_cpus; cpu ++) {
c70975bc	104	fd[cpu][counter] = sys_perf_counter_open(&attr, -1, cpu, -1, 0);
ddcacfa0 IM	105	if (fd[cpu][counter] < 0) {
	106	printf("perfstat error: syscall returned with %d (%s)\n",
	107	fd[cpu][counter], strerror(errno));
	108	exit(-1);
	109	}
	110	}
	111	} else {
c70975bc PZ	112	attr.inherit = inherit;
c70975bc PZ	113	attr.disabled = 1;
ddcacfa0	114
c70975bc	115	fd[0][counter] = sys_perf_counter_open(&attr, 0, -1, -1, 0);
ddcacfa0 IM	116	if (fd[0][counter] < 0) {
	117	printf("perfstat error: syscall returned with %d (%s)\n",
	118	fd[0][counter], strerror(errno));
	119	exit(-1);
	120	}
	121	}
	122	}
	123
c04f5e5d IM	124	/*
	125	* Does the counter have nsecs as a unit?
	126	*/
	127	static inline int nsec_counter(int counter)
	128	{
	129	if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_CLOCK))
	130	return 1;
	131	if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK))
	132	return 1;
	133
	134	return 0;
	135	}
	136
	137	/*
2996f5dd	138	* Read out the results of a single counter:
c04f5e5d	139	*/
2996f5dd	140	static void read_counter(int counter)
c04f5e5d	141	{
2996f5dd	142	__u64 *count, single_count[3];
c04f5e5d IM	143	ssize_t res;
	144	int cpu, nv;
	145	int scaled;
	146
2996f5dd IM	147	count = event_res[counter];
2996f5dd IM	148
c04f5e5d	149	count[0] = count[1] = count[2] = 0;
2996f5dd	150
c04f5e5d IM	151	nv = scale ? 3 : 1;
	152	for (cpu = 0; cpu < nr_cpus; cpu ++) {
	153	res = read(fd[cpu][counter], single_count, nv * sizeof(__u64));
	154	assert(res == nv * sizeof(__u64));
	155
	156	count[0] += single_count[0];
	157	if (scale) {
	158	count[1] += single_count[1];
	159	count[2] += single_count[2];
	160	}
	161	}
	162
	163	scaled = 0;
	164	if (scale) {
	165	if (count[2] == 0) {
2996f5dd IM	166	event_scaled[counter] = -1;
2996f5dd IM	167	count[0] = 0;
c04f5e5d IM	168	return;
c04f5e5d IM	169	}
2996f5dd	170
c04f5e5d	171	if (count[2] < count[1]) {
2996f5dd	172	event_scaled[counter] = 1;
c04f5e5d IM	173	count[0] = (unsigned long long)
	174	((double)count[0] * count[1] / count[2] + 0.5);
	175	}
	176	}
be1ac0d8 IM	177	/*
	178	* Save the full runtime - to allow normalization during printout:
	179	*/
	180	if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK))
	181	runtime_nsecs = count[0];
2996f5dd IM	182	}
	183
	184	/*
	185	* Print out the results of a single counter:
	186	*/
	187	static void print_counter(int counter)
	188	{
	189	__u64 *count;
	190	int scaled;
	191
	192	count = event_res[counter];
	193	scaled = event_scaled[counter];
	194
	195	if (scaled == -1) {
	196	fprintf(stderr, " %14s %-20s\n",
	197	"<not counted>", event_name(counter));
	198	return;
	199	}
c04f5e5d IM	200
	201	if (nsec_counter(counter)) {
	202	double msecs = (double)count[0] / 1000000;
	203
d7c29318	204	fprintf(stderr, " %14.6f %-20s",
c04f5e5d	205	msecs, event_name(counter));
d7c29318 IM	206	if (event_id[counter] ==
	207	EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK)) {
	208
	209	fprintf(stderr, " # %11.3f CPU utilization factor",
	210	(double)count[0] / (double)walltime_nsecs);
	211	}
c04f5e5d	212	} else {
be1ac0d8	213	fprintf(stderr, " %14Ld %-20s",
c04f5e5d	214	count[0], event_name(counter));
be1ac0d8	215	if (runtime_nsecs)
d7c29318	216	fprintf(stderr, " # %11.3f M/sec",
be1ac0d8	217	(double)count[0]/runtime_nsecs*1000.0);
c04f5e5d IM	218	}
	219	if (scaled)
	220	fprintf(stderr, " (scaled from %.2f%%)",
	221	(double) count[2] / count[1] * 100);
	222	fprintf(stderr, "\n");
	223	}
	224
16f762a2	225	static int do_perfstat(int argc, const char **argv)
ddcacfa0 IM	226	{
	227	unsigned long long t0, t1;
	228	int counter;
ddcacfa0 IM	229	int status;
ddcacfa0 IM	230	int pid;
44db76c8	231	int i;
ddcacfa0 IM	232
	233	if (!system_wide)
	234	nr_cpus = 1;
	235
	236	for (counter = 0; counter < nr_counters; counter++)
	237	create_perfstat_counter(counter);
	238
ddcacfa0 IM	239	/*
	240	* Enable counters and exec the command:
	241	*/
	242	t0 = rdclock();
	243	prctl(PR_TASK_PERF_COUNTERS_ENABLE);
	244
	245	if ((pid = fork()) < 0)
	246	perror("failed to fork");
44db76c8	247
ddcacfa0	248	if (!pid) {
5242519b	249	if (execvp(argv[0], (char **)argv)) {
ddcacfa0 IM	250	perror(argv[0]);
	251	exit(-1);
	252	}
	253	}
44db76c8	254
ddcacfa0 IM	255	while (wait(&status) >= 0)
ddcacfa0 IM	256	;
44db76c8	257
ddcacfa0 IM	258	prctl(PR_TASK_PERF_COUNTERS_DISABLE);
	259	t1 = rdclock();
	260
d7c29318 IM	261	walltime_nsecs = t1 - t0;
d7c29318 IM	262
ddcacfa0 IM	263	fflush(stdout);
	264
	265	fprintf(stderr, "\n");
44db76c8 IM	266	fprintf(stderr, " Performance counter stats for \'%s", argv[0]);
	267
	268	for (i = 1; i < argc; i++)
	269	fprintf(stderr, " %s", argv[i]);
	270
	271	fprintf(stderr, "\':\n");
ddcacfa0 IM	272	fprintf(stderr, "\n");
ddcacfa0 IM	273
2996f5dd IM	274	for (counter = 0; counter < nr_counters; counter++)
	275	read_counter(counter);
	276
c04f5e5d IM	277	for (counter = 0; counter < nr_counters; counter++)
c04f5e5d IM	278	print_counter(counter);
ddcacfa0	279
ddcacfa0	280
ddcacfa0 IM	281	fprintf(stderr, "\n");
	282	fprintf(stderr, " Wall-clock time elapsed: %12.6f msecs\n",
	283	(double)(t1-t0)/1e6);
	284	fprintf(stderr, "\n");
	285
	286	return 0;
	287	}
	288
5242519b	289	static void skip_signal(int signo)
ddcacfa0	290	{
5242519b IM	291	}
	292
	293	static const char * const stat_usage[] = {
	294	"perf stat [<options>] <command>",
	295	NULL
	296	};
	297
	298	static char events_help_msg[EVENTS_HELP_MAX];
	299
	300	static const struct option options[] = {
	301	OPT_CALLBACK('e', "event", NULL, "event",
	302	events_help_msg, parse_events),
	303	OPT_INTEGER('c', "count", &default_interval,
	304	"event period to sample"),
	305	OPT_BOOLEAN('i', "inherit", &inherit,
	306	"child tasks inherit counters"),
	307	OPT_INTEGER('p', "pid", &target_pid,
	308	"stat events on existing pid"),
	309	OPT_BOOLEAN('a', "all-cpus", &system_wide,
	310	"system-wide collection from all CPUs"),
	311	OPT_BOOLEAN('l', "scale", &scale,
	312	"scale/normalize counters"),
	313	OPT_END()
	314	};
	315
	316	int cmd_stat(int argc, const char *argv, const char prefix)
	317	{
	318	int counter;
	319
	320	page_size = sysconf(_SC_PAGE_SIZE);
	321
	322	create_events_help(events_help_msg);
	323	memcpy(event_id, default_event_id, sizeof(default_event_id));
	324
	325	argc = parse_options(argc, argv, options, stat_usage, 0);
	326	if (!argc)
	327	usage_with_options(stat_usage, options);
ddcacfa0 IM	328
	329	if (!nr_counters) {
	330	nr_counters = 8;
	331	}
	332
	333	for (counter = 0; counter < nr_counters; counter++) {
	334	if (event_count[counter])
	335	continue;
	336
	337	event_count[counter] = default_interval;
	338	}
ddcacfa0 IM	339	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
	340	assert(nr_cpus <= MAX_NR_CPUS);
	341	assert(nr_cpus >= 0);
	342
58d7e993 IM	343	/*
	344	* We dont want to block the signals - that would cause
	345	* child tasks to inherit that and Ctrl-C would not work.
	346	* What we want is for Ctrl-C to work in the exec()-ed
	347	* task, but being ignored by perf stat itself:
	348	*/
	349	signal(SIGINT, skip_signal);
	350	signal(SIGALRM, skip_signal);
	351	signal(SIGABRT, skip_signal);
	352
ddcacfa0 IM	353	return do_perfstat(argc, argv);
ddcacfa0 IM	354	}