xref: /openbmc/linux/tools/perf/builtin-stat.c (revision a2cce7a9)
1 /*
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:
8 
9    $ perf stat ./hackbench 10
10 
11   Time: 0.118
12 
13   Performance counter stats for './hackbench 10':
14 
15        1708.761321 task-clock                #   11.037 CPUs utilized
16             41,190 context-switches          #    0.024 M/sec
17              6,735 CPU-migrations            #    0.004 M/sec
18             17,318 page-faults               #    0.010 M/sec
19      5,205,202,243 cycles                    #    3.046 GHz
20      3,856,436,920 stalled-cycles-frontend   #   74.09% frontend cycles idle
21      1,600,790,871 stalled-cycles-backend    #   30.75% backend  cycles idle
22      2,603,501,247 instructions              #    0.50  insns per cycle
23                                              #    1.48  stalled cycles per insn
24        484,357,498 branches                  #  283.455 M/sec
25          6,388,934 branch-misses             #    1.32% of all branches
26 
27         0.154822978  seconds time elapsed
28 
29  *
30  * Copyright (C) 2008-2011, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
31  *
32  * Improvements and fixes by:
33  *
34  *   Arjan van de Ven <arjan@linux.intel.com>
35  *   Yanmin Zhang <yanmin.zhang@intel.com>
36  *   Wu Fengguang <fengguang.wu@intel.com>
37  *   Mike Galbraith <efault@gmx.de>
38  *   Paul Mackerras <paulus@samba.org>
39  *   Jaswinder Singh Rajput <jaswinder@kernel.org>
40  *
41  * Released under the GPL v2. (and only v2, not any later version)
42  */
43 
44 #include "perf.h"
45 #include "builtin.h"
46 #include "util/cgroup.h"
47 #include "util/util.h"
48 #include "util/parse-options.h"
49 #include "util/parse-events.h"
50 #include "util/pmu.h"
51 #include "util/event.h"
52 #include "util/evlist.h"
53 #include "util/evsel.h"
54 #include "util/debug.h"
55 #include "util/color.h"
56 #include "util/stat.h"
57 #include "util/header.h"
58 #include "util/cpumap.h"
59 #include "util/thread.h"
60 #include "util/thread_map.h"
61 #include "util/counts.h"
62 
63 #include <stdlib.h>
64 #include <sys/prctl.h>
65 #include <locale.h>
66 
67 #define DEFAULT_SEPARATOR	" "
68 #define CNTR_NOT_SUPPORTED	"<not supported>"
69 #define CNTR_NOT_COUNTED	"<not counted>"
70 
71 static void print_counters(struct timespec *ts, int argc, const char **argv);
72 
73 /* Default events used for perf stat -T */
74 static const char *transaction_attrs = {
75 	"task-clock,"
76 	"{"
77 	"instructions,"
78 	"cycles,"
79 	"cpu/cycles-t/,"
80 	"cpu/tx-start/,"
81 	"cpu/el-start/,"
82 	"cpu/cycles-ct/"
83 	"}"
84 };
85 
86 /* More limited version when the CPU does not have all events. */
87 static const char * transaction_limited_attrs = {
88 	"task-clock,"
89 	"{"
90 	"instructions,"
91 	"cycles,"
92 	"cpu/cycles-t/,"
93 	"cpu/tx-start/"
94 	"}"
95 };
96 
97 static struct perf_evlist	*evsel_list;
98 
99 static struct target target = {
100 	.uid	= UINT_MAX,
101 };
102 
103 static int			run_count			=  1;
104 static bool			no_inherit			= false;
105 static volatile pid_t		child_pid			= -1;
106 static bool			null_run			=  false;
107 static int			detailed_run			=  0;
108 static bool			transaction_run;
109 static bool			big_num				=  true;
110 static int			big_num_opt			=  -1;
111 static const char		*csv_sep			= NULL;
112 static bool			csv_output			= false;
113 static bool			group				= false;
114 static const char		*pre_cmd			= NULL;
115 static const char		*post_cmd			= NULL;
116 static bool			sync_run			= false;
117 static unsigned int		initial_delay			= 0;
118 static unsigned int		unit_width			= 4; /* strlen("unit") */
119 static bool			forever				= false;
120 static struct timespec		ref_time;
121 static struct cpu_map		*aggr_map;
122 static int			(*aggr_get_id)(struct cpu_map *m, int cpu);
123 
124 static volatile int done = 0;
125 
126 static struct perf_stat_config stat_config = {
127 	.aggr_mode	= AGGR_GLOBAL,
128 	.scale		= true,
129 };
130 
131 static inline void diff_timespec(struct timespec *r, struct timespec *a,
132 				 struct timespec *b)
133 {
134 	r->tv_sec = a->tv_sec - b->tv_sec;
135 	if (a->tv_nsec < b->tv_nsec) {
136 		r->tv_nsec = a->tv_nsec + 1000000000L - b->tv_nsec;
137 		r->tv_sec--;
138 	} else {
139 		r->tv_nsec = a->tv_nsec - b->tv_nsec ;
140 	}
141 }
142 
143 static void perf_stat__reset_stats(void)
144 {
145 	perf_evlist__reset_stats(evsel_list);
146 	perf_stat__reset_shadow_stats();
147 }
148 
149 static int create_perf_stat_counter(struct perf_evsel *evsel)
150 {
151 	struct perf_event_attr *attr = &evsel->attr;
152 
153 	if (stat_config.scale)
154 		attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
155 				    PERF_FORMAT_TOTAL_TIME_RUNNING;
156 
157 	attr->inherit = !no_inherit;
158 
159 	if (target__has_cpu(&target))
160 		return perf_evsel__open_per_cpu(evsel, perf_evsel__cpus(evsel));
161 
162 	if (!target__has_task(&target) && perf_evsel__is_group_leader(evsel)) {
163 		attr->disabled = 1;
164 		if (!initial_delay)
165 			attr->enable_on_exec = 1;
166 	}
167 
168 	return perf_evsel__open_per_thread(evsel, evsel_list->threads);
169 }
170 
171 /*
172  * Does the counter have nsecs as a unit?
173  */
174 static inline int nsec_counter(struct perf_evsel *evsel)
175 {
176 	if (perf_evsel__match(evsel, SOFTWARE, SW_CPU_CLOCK) ||
177 	    perf_evsel__match(evsel, SOFTWARE, SW_TASK_CLOCK))
178 		return 1;
179 
180 	return 0;
181 }
182 
183 /*
184  * Read out the results of a single counter:
185  * do not aggregate counts across CPUs in system-wide mode
186  */
187 static int read_counter(struct perf_evsel *counter)
188 {
189 	int nthreads = thread_map__nr(evsel_list->threads);
190 	int ncpus = perf_evsel__nr_cpus(counter);
191 	int cpu, thread;
192 
193 	if (!counter->supported)
194 		return -ENOENT;
195 
196 	if (counter->system_wide)
197 		nthreads = 1;
198 
199 	for (thread = 0; thread < nthreads; thread++) {
200 		for (cpu = 0; cpu < ncpus; cpu++) {
201 			struct perf_counts_values *count;
202 
203 			count = perf_counts(counter->counts, cpu, thread);
204 			if (perf_evsel__read(counter, cpu, thread, count))
205 				return -1;
206 		}
207 	}
208 
209 	return 0;
210 }
211 
212 static void read_counters(bool close_counters)
213 {
214 	struct perf_evsel *counter;
215 
216 	evlist__for_each(evsel_list, counter) {
217 		if (read_counter(counter))
218 			pr_warning("failed to read counter %s\n", counter->name);
219 
220 		if (perf_stat_process_counter(&stat_config, counter))
221 			pr_warning("failed to process counter %s\n", counter->name);
222 
223 		if (close_counters) {
224 			perf_evsel__close_fd(counter, perf_evsel__nr_cpus(counter),
225 					     thread_map__nr(evsel_list->threads));
226 		}
227 	}
228 }
229 
230 static void process_interval(void)
231 {
232 	struct timespec ts, rs;
233 
234 	read_counters(false);
235 
236 	clock_gettime(CLOCK_MONOTONIC, &ts);
237 	diff_timespec(&rs, &ts, &ref_time);
238 
239 	print_counters(&rs, 0, NULL);
240 }
241 
242 static void handle_initial_delay(void)
243 {
244 	struct perf_evsel *counter;
245 
246 	if (initial_delay) {
247 		const int ncpus = cpu_map__nr(evsel_list->cpus),
248 			nthreads = thread_map__nr(evsel_list->threads);
249 
250 		usleep(initial_delay * 1000);
251 		evlist__for_each(evsel_list, counter)
252 			perf_evsel__enable(counter, ncpus, nthreads);
253 	}
254 }
255 
256 static volatile int workload_exec_errno;
257 
258 /*
259  * perf_evlist__prepare_workload will send a SIGUSR1
260  * if the fork fails, since we asked by setting its
261  * want_signal to true.
262  */
263 static void workload_exec_failed_signal(int signo __maybe_unused, siginfo_t *info,
264 					void *ucontext __maybe_unused)
265 {
266 	workload_exec_errno = info->si_value.sival_int;
267 }
268 
269 static int __run_perf_stat(int argc, const char **argv)
270 {
271 	int interval = stat_config.interval;
272 	char msg[512];
273 	unsigned long long t0, t1;
274 	struct perf_evsel *counter;
275 	struct timespec ts;
276 	size_t l;
277 	int status = 0;
278 	const bool forks = (argc > 0);
279 
280 	if (interval) {
281 		ts.tv_sec  = interval / 1000;
282 		ts.tv_nsec = (interval % 1000) * 1000000;
283 	} else {
284 		ts.tv_sec  = 1;
285 		ts.tv_nsec = 0;
286 	}
287 
288 	if (forks) {
289 		if (perf_evlist__prepare_workload(evsel_list, &target, argv, false,
290 						  workload_exec_failed_signal) < 0) {
291 			perror("failed to prepare workload");
292 			return -1;
293 		}
294 		child_pid = evsel_list->workload.pid;
295 	}
296 
297 	if (group)
298 		perf_evlist__set_leader(evsel_list);
299 
300 	evlist__for_each(evsel_list, counter) {
301 		if (create_perf_stat_counter(counter) < 0) {
302 			/*
303 			 * PPC returns ENXIO for HW counters until 2.6.37
304 			 * (behavior changed with commit b0a873e).
305 			 */
306 			if (errno == EINVAL || errno == ENOSYS ||
307 			    errno == ENOENT || errno == EOPNOTSUPP ||
308 			    errno == ENXIO) {
309 				if (verbose)
310 					ui__warning("%s event is not supported by the kernel.\n",
311 						    perf_evsel__name(counter));
312 				counter->supported = false;
313 
314 				if ((counter->leader != counter) ||
315 				    !(counter->leader->nr_members > 1))
316 					continue;
317 			}
318 
319 			perf_evsel__open_strerror(counter, &target,
320 						  errno, msg, sizeof(msg));
321 			ui__error("%s\n", msg);
322 
323 			if (child_pid != -1)
324 				kill(child_pid, SIGTERM);
325 
326 			return -1;
327 		}
328 		counter->supported = true;
329 
330 		l = strlen(counter->unit);
331 		if (l > unit_width)
332 			unit_width = l;
333 	}
334 
335 	if (perf_evlist__apply_filters(evsel_list, &counter)) {
336 		error("failed to set filter \"%s\" on event %s with %d (%s)\n",
337 			counter->filter, perf_evsel__name(counter), errno,
338 			strerror_r(errno, msg, sizeof(msg)));
339 		return -1;
340 	}
341 
342 	/*
343 	 * Enable counters and exec the command:
344 	 */
345 	t0 = rdclock();
346 	clock_gettime(CLOCK_MONOTONIC, &ref_time);
347 
348 	if (forks) {
349 		perf_evlist__start_workload(evsel_list);
350 		handle_initial_delay();
351 
352 		if (interval) {
353 			while (!waitpid(child_pid, &status, WNOHANG)) {
354 				nanosleep(&ts, NULL);
355 				process_interval();
356 			}
357 		}
358 		wait(&status);
359 
360 		if (workload_exec_errno) {
361 			const char *emsg = strerror_r(workload_exec_errno, msg, sizeof(msg));
362 			pr_err("Workload failed: %s\n", emsg);
363 			return -1;
364 		}
365 
366 		if (WIFSIGNALED(status))
367 			psignal(WTERMSIG(status), argv[0]);
368 	} else {
369 		handle_initial_delay();
370 		while (!done) {
371 			nanosleep(&ts, NULL);
372 			if (interval)
373 				process_interval();
374 		}
375 	}
376 
377 	t1 = rdclock();
378 
379 	update_stats(&walltime_nsecs_stats, t1 - t0);
380 
381 	read_counters(true);
382 
383 	return WEXITSTATUS(status);
384 }
385 
386 static int run_perf_stat(int argc, const char **argv)
387 {
388 	int ret;
389 
390 	if (pre_cmd) {
391 		ret = system(pre_cmd);
392 		if (ret)
393 			return ret;
394 	}
395 
396 	if (sync_run)
397 		sync();
398 
399 	ret = __run_perf_stat(argc, argv);
400 	if (ret)
401 		return ret;
402 
403 	if (post_cmd) {
404 		ret = system(post_cmd);
405 		if (ret)
406 			return ret;
407 	}
408 
409 	return ret;
410 }
411 
412 static void print_running(u64 run, u64 ena)
413 {
414 	if (csv_output) {
415 		fprintf(stat_config.output, "%s%" PRIu64 "%s%.2f",
416 					csv_sep,
417 					run,
418 					csv_sep,
419 					ena ? 100.0 * run / ena : 100.0);
420 	} else if (run != ena) {
421 		fprintf(stat_config.output, "  (%.2f%%)", 100.0 * run / ena);
422 	}
423 }
424 
425 static void print_noise_pct(double total, double avg)
426 {
427 	double pct = rel_stddev_stats(total, avg);
428 
429 	if (csv_output)
430 		fprintf(stat_config.output, "%s%.2f%%", csv_sep, pct);
431 	else if (pct)
432 		fprintf(stat_config.output, "  ( +-%6.2f%% )", pct);
433 }
434 
435 static void print_noise(struct perf_evsel *evsel, double avg)
436 {
437 	struct perf_stat *ps;
438 
439 	if (run_count == 1)
440 		return;
441 
442 	ps = evsel->priv;
443 	print_noise_pct(stddev_stats(&ps->res_stats[0]), avg);
444 }
445 
446 static void aggr_printout(struct perf_evsel *evsel, int id, int nr)
447 {
448 	switch (stat_config.aggr_mode) {
449 	case AGGR_CORE:
450 		fprintf(stat_config.output, "S%d-C%*d%s%*d%s",
451 			cpu_map__id_to_socket(id),
452 			csv_output ? 0 : -8,
453 			cpu_map__id_to_cpu(id),
454 			csv_sep,
455 			csv_output ? 0 : 4,
456 			nr,
457 			csv_sep);
458 		break;
459 	case AGGR_SOCKET:
460 		fprintf(stat_config.output, "S%*d%s%*d%s",
461 			csv_output ? 0 : -5,
462 			id,
463 			csv_sep,
464 			csv_output ? 0 : 4,
465 			nr,
466 			csv_sep);
467 			break;
468 	case AGGR_NONE:
469 		fprintf(stat_config.output, "CPU%*d%s",
470 			csv_output ? 0 : -4,
471 			perf_evsel__cpus(evsel)->map[id], csv_sep);
472 		break;
473 	case AGGR_THREAD:
474 		fprintf(stat_config.output, "%*s-%*d%s",
475 			csv_output ? 0 : 16,
476 			thread_map__comm(evsel->threads, id),
477 			csv_output ? 0 : -8,
478 			thread_map__pid(evsel->threads, id),
479 			csv_sep);
480 		break;
481 	case AGGR_GLOBAL:
482 	default:
483 		break;
484 	}
485 }
486 
487 static void nsec_printout(int id, int nr, struct perf_evsel *evsel, double avg)
488 {
489 	FILE *output = stat_config.output;
490 	double msecs = avg / 1e6;
491 	const char *fmt_v, *fmt_n;
492 	char name[25];
493 
494 	fmt_v = csv_output ? "%.6f%s" : "%18.6f%s";
495 	fmt_n = csv_output ? "%s" : "%-25s";
496 
497 	aggr_printout(evsel, id, nr);
498 
499 	scnprintf(name, sizeof(name), "%s%s",
500 		  perf_evsel__name(evsel), csv_output ? "" : " (msec)");
501 
502 	fprintf(output, fmt_v, msecs, csv_sep);
503 
504 	if (csv_output)
505 		fprintf(output, "%s%s", evsel->unit, csv_sep);
506 	else
507 		fprintf(output, "%-*s%s", unit_width, evsel->unit, csv_sep);
508 
509 	fprintf(output, fmt_n, name);
510 
511 	if (evsel->cgrp)
512 		fprintf(output, "%s%s", csv_sep, evsel->cgrp->name);
513 
514 	if (csv_output || stat_config.interval)
515 		return;
516 
517 	if (perf_evsel__match(evsel, SOFTWARE, SW_TASK_CLOCK))
518 		fprintf(output, " # %8.3f CPUs utilized          ",
519 			avg / avg_stats(&walltime_nsecs_stats));
520 	else
521 		fprintf(output, "                                   ");
522 }
523 
524 static void abs_printout(int id, int nr, struct perf_evsel *evsel, double avg)
525 {
526 	FILE *output = stat_config.output;
527 	double sc =  evsel->scale;
528 	const char *fmt;
529 	int cpu = cpu_map__id_to_cpu(id);
530 
531 	if (csv_output) {
532 		fmt = sc != 1.0 ?  "%.2f%s" : "%.0f%s";
533 	} else {
534 		if (big_num)
535 			fmt = sc != 1.0 ? "%'18.2f%s" : "%'18.0f%s";
536 		else
537 			fmt = sc != 1.0 ? "%18.2f%s" : "%18.0f%s";
538 	}
539 
540 	aggr_printout(evsel, id, nr);
541 
542 	if (stat_config.aggr_mode == AGGR_GLOBAL)
543 		cpu = 0;
544 
545 	fprintf(output, fmt, avg, csv_sep);
546 
547 	if (evsel->unit)
548 		fprintf(output, "%-*s%s",
549 			csv_output ? 0 : unit_width,
550 			evsel->unit, csv_sep);
551 
552 	fprintf(output, "%-*s", csv_output ? 0 : 25, perf_evsel__name(evsel));
553 
554 	if (evsel->cgrp)
555 		fprintf(output, "%s%s", csv_sep, evsel->cgrp->name);
556 
557 	if (csv_output || stat_config.interval)
558 		return;
559 
560 	perf_stat__print_shadow_stats(output, evsel, avg, cpu,
561 				      stat_config.aggr_mode);
562 }
563 
564 static void print_aggr(char *prefix)
565 {
566 	FILE *output = stat_config.output;
567 	struct perf_evsel *counter;
568 	int cpu, s, s2, id, nr;
569 	double uval;
570 	u64 ena, run, val;
571 
572 	if (!(aggr_map || aggr_get_id))
573 		return;
574 
575 	for (s = 0; s < aggr_map->nr; s++) {
576 		id = aggr_map->map[s];
577 		evlist__for_each(evsel_list, counter) {
578 			val = ena = run = 0;
579 			nr = 0;
580 			for (cpu = 0; cpu < perf_evsel__nr_cpus(counter); cpu++) {
581 				s2 = aggr_get_id(perf_evsel__cpus(counter), cpu);
582 				if (s2 != id)
583 					continue;
584 				val += perf_counts(counter->counts, cpu, 0)->val;
585 				ena += perf_counts(counter->counts, cpu, 0)->ena;
586 				run += perf_counts(counter->counts, cpu, 0)->run;
587 				nr++;
588 			}
589 			if (prefix)
590 				fprintf(output, "%s", prefix);
591 
592 			if (run == 0 || ena == 0) {
593 				aggr_printout(counter, id, nr);
594 
595 				fprintf(output, "%*s%s",
596 					csv_output ? 0 : 18,
597 					counter->supported ? CNTR_NOT_COUNTED : CNTR_NOT_SUPPORTED,
598 					csv_sep);
599 
600 				fprintf(output, "%-*s%s",
601 					csv_output ? 0 : unit_width,
602 					counter->unit, csv_sep);
603 
604 				fprintf(output, "%*s",
605 					csv_output ? 0 : -25,
606 					perf_evsel__name(counter));
607 
608 				if (counter->cgrp)
609 					fprintf(output, "%s%s",
610 						csv_sep, counter->cgrp->name);
611 
612 				print_running(run, ena);
613 				fputc('\n', output);
614 				continue;
615 			}
616 			uval = val * counter->scale;
617 
618 			if (nsec_counter(counter))
619 				nsec_printout(id, nr, counter, uval);
620 			else
621 				abs_printout(id, nr, counter, uval);
622 
623 			if (!csv_output)
624 				print_noise(counter, 1.0);
625 
626 			print_running(run, ena);
627 			fputc('\n', output);
628 		}
629 	}
630 }
631 
632 static void print_aggr_thread(struct perf_evsel *counter, char *prefix)
633 {
634 	FILE *output = stat_config.output;
635 	int nthreads = thread_map__nr(counter->threads);
636 	int ncpus = cpu_map__nr(counter->cpus);
637 	int cpu, thread;
638 	double uval;
639 
640 	for (thread = 0; thread < nthreads; thread++) {
641 		u64 ena = 0, run = 0, val = 0;
642 
643 		for (cpu = 0; cpu < ncpus; cpu++) {
644 			val += perf_counts(counter->counts, cpu, thread)->val;
645 			ena += perf_counts(counter->counts, cpu, thread)->ena;
646 			run += perf_counts(counter->counts, cpu, thread)->run;
647 		}
648 
649 		if (prefix)
650 			fprintf(output, "%s", prefix);
651 
652 		uval = val * counter->scale;
653 
654 		if (nsec_counter(counter))
655 			nsec_printout(thread, 0, counter, uval);
656 		else
657 			abs_printout(thread, 0, counter, uval);
658 
659 		if (!csv_output)
660 			print_noise(counter, 1.0);
661 
662 		print_running(run, ena);
663 		fputc('\n', output);
664 	}
665 }
666 
667 /*
668  * Print out the results of a single counter:
669  * aggregated counts in system-wide mode
670  */
671 static void print_counter_aggr(struct perf_evsel *counter, char *prefix)
672 {
673 	FILE *output = stat_config.output;
674 	struct perf_stat *ps = counter->priv;
675 	double avg = avg_stats(&ps->res_stats[0]);
676 	int scaled = counter->counts->scaled;
677 	double uval;
678 	double avg_enabled, avg_running;
679 
680 	avg_enabled = avg_stats(&ps->res_stats[1]);
681 	avg_running = avg_stats(&ps->res_stats[2]);
682 
683 	if (prefix)
684 		fprintf(output, "%s", prefix);
685 
686 	if (scaled == -1 || !counter->supported) {
687 		fprintf(output, "%*s%s",
688 			csv_output ? 0 : 18,
689 			counter->supported ? CNTR_NOT_COUNTED : CNTR_NOT_SUPPORTED,
690 			csv_sep);
691 		fprintf(output, "%-*s%s",
692 			csv_output ? 0 : unit_width,
693 			counter->unit, csv_sep);
694 		fprintf(output, "%*s",
695 			csv_output ? 0 : -25,
696 			perf_evsel__name(counter));
697 
698 		if (counter->cgrp)
699 			fprintf(output, "%s%s", csv_sep, counter->cgrp->name);
700 
701 		print_running(avg_running, avg_enabled);
702 		fputc('\n', output);
703 		return;
704 	}
705 
706 	uval = avg * counter->scale;
707 
708 	if (nsec_counter(counter))
709 		nsec_printout(-1, 0, counter, uval);
710 	else
711 		abs_printout(-1, 0, counter, uval);
712 
713 	print_noise(counter, avg);
714 
715 	print_running(avg_running, avg_enabled);
716 	fprintf(output, "\n");
717 }
718 
719 /*
720  * Print out the results of a single counter:
721  * does not use aggregated count in system-wide
722  */
723 static void print_counter(struct perf_evsel *counter, char *prefix)
724 {
725 	FILE *output = stat_config.output;
726 	u64 ena, run, val;
727 	double uval;
728 	int cpu;
729 
730 	for (cpu = 0; cpu < perf_evsel__nr_cpus(counter); cpu++) {
731 		val = perf_counts(counter->counts, cpu, 0)->val;
732 		ena = perf_counts(counter->counts, cpu, 0)->ena;
733 		run = perf_counts(counter->counts, cpu, 0)->run;
734 
735 		if (prefix)
736 			fprintf(output, "%s", prefix);
737 
738 		if (run == 0 || ena == 0) {
739 			fprintf(output, "CPU%*d%s%*s%s",
740 				csv_output ? 0 : -4,
741 				perf_evsel__cpus(counter)->map[cpu], csv_sep,
742 				csv_output ? 0 : 18,
743 				counter->supported ? CNTR_NOT_COUNTED : CNTR_NOT_SUPPORTED,
744 				csv_sep);
745 
746 				fprintf(output, "%-*s%s",
747 					csv_output ? 0 : unit_width,
748 					counter->unit, csv_sep);
749 
750 				fprintf(output, "%*s",
751 					csv_output ? 0 : -25,
752 					perf_evsel__name(counter));
753 
754 			if (counter->cgrp)
755 				fprintf(output, "%s%s",
756 					csv_sep, counter->cgrp->name);
757 
758 			print_running(run, ena);
759 			fputc('\n', output);
760 			continue;
761 		}
762 
763 		uval = val * counter->scale;
764 
765 		if (nsec_counter(counter))
766 			nsec_printout(cpu, 0, counter, uval);
767 		else
768 			abs_printout(cpu, 0, counter, uval);
769 
770 		if (!csv_output)
771 			print_noise(counter, 1.0);
772 		print_running(run, ena);
773 
774 		fputc('\n', output);
775 	}
776 }
777 
778 static void print_interval(char *prefix, struct timespec *ts)
779 {
780 	FILE *output = stat_config.output;
781 	static int num_print_interval;
782 
783 	sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, csv_sep);
784 
785 	if (num_print_interval == 0 && !csv_output) {
786 		switch (stat_config.aggr_mode) {
787 		case AGGR_SOCKET:
788 			fprintf(output, "#           time socket cpus             counts %*s events\n", unit_width, "unit");
789 			break;
790 		case AGGR_CORE:
791 			fprintf(output, "#           time core         cpus             counts %*s events\n", unit_width, "unit");
792 			break;
793 		case AGGR_NONE:
794 			fprintf(output, "#           time CPU                counts %*s events\n", unit_width, "unit");
795 			break;
796 		case AGGR_THREAD:
797 			fprintf(output, "#           time             comm-pid                  counts %*s events\n", unit_width, "unit");
798 			break;
799 		case AGGR_GLOBAL:
800 		default:
801 			fprintf(output, "#           time             counts %*s events\n", unit_width, "unit");
802 		}
803 	}
804 
805 	if (++num_print_interval == 25)
806 		num_print_interval = 0;
807 }
808 
809 static void print_header(int argc, const char **argv)
810 {
811 	FILE *output = stat_config.output;
812 	int i;
813 
814 	fflush(stdout);
815 
816 	if (!csv_output) {
817 		fprintf(output, "\n");
818 		fprintf(output, " Performance counter stats for ");
819 		if (target.system_wide)
820 			fprintf(output, "\'system wide");
821 		else if (target.cpu_list)
822 			fprintf(output, "\'CPU(s) %s", target.cpu_list);
823 		else if (!target__has_task(&target)) {
824 			fprintf(output, "\'%s", argv[0]);
825 			for (i = 1; i < argc; i++)
826 				fprintf(output, " %s", argv[i]);
827 		} else if (target.pid)
828 			fprintf(output, "process id \'%s", target.pid);
829 		else
830 			fprintf(output, "thread id \'%s", target.tid);
831 
832 		fprintf(output, "\'");
833 		if (run_count > 1)
834 			fprintf(output, " (%d runs)", run_count);
835 		fprintf(output, ":\n\n");
836 	}
837 }
838 
839 static void print_footer(void)
840 {
841 	FILE *output = stat_config.output;
842 
843 	if (!null_run)
844 		fprintf(output, "\n");
845 	fprintf(output, " %17.9f seconds time elapsed",
846 			avg_stats(&walltime_nsecs_stats)/1e9);
847 	if (run_count > 1) {
848 		fprintf(output, "                                        ");
849 		print_noise_pct(stddev_stats(&walltime_nsecs_stats),
850 				avg_stats(&walltime_nsecs_stats));
851 	}
852 	fprintf(output, "\n\n");
853 }
854 
855 static void print_counters(struct timespec *ts, int argc, const char **argv)
856 {
857 	int interval = stat_config.interval;
858 	struct perf_evsel *counter;
859 	char buf[64], *prefix = NULL;
860 
861 	if (interval)
862 		print_interval(prefix = buf, ts);
863 	else
864 		print_header(argc, argv);
865 
866 	switch (stat_config.aggr_mode) {
867 	case AGGR_CORE:
868 	case AGGR_SOCKET:
869 		print_aggr(prefix);
870 		break;
871 	case AGGR_THREAD:
872 		evlist__for_each(evsel_list, counter)
873 			print_aggr_thread(counter, prefix);
874 		break;
875 	case AGGR_GLOBAL:
876 		evlist__for_each(evsel_list, counter)
877 			print_counter_aggr(counter, prefix);
878 		break;
879 	case AGGR_NONE:
880 		evlist__for_each(evsel_list, counter)
881 			print_counter(counter, prefix);
882 		break;
883 	default:
884 		break;
885 	}
886 
887 	if (!interval && !csv_output)
888 		print_footer();
889 
890 	fflush(stat_config.output);
891 }
892 
893 static volatile int signr = -1;
894 
895 static void skip_signal(int signo)
896 {
897 	if ((child_pid == -1) || stat_config.interval)
898 		done = 1;
899 
900 	signr = signo;
901 	/*
902 	 * render child_pid harmless
903 	 * won't send SIGTERM to a random
904 	 * process in case of race condition
905 	 * and fast PID recycling
906 	 */
907 	child_pid = -1;
908 }
909 
910 static void sig_atexit(void)
911 {
912 	sigset_t set, oset;
913 
914 	/*
915 	 * avoid race condition with SIGCHLD handler
916 	 * in skip_signal() which is modifying child_pid
917 	 * goal is to avoid send SIGTERM to a random
918 	 * process
919 	 */
920 	sigemptyset(&set);
921 	sigaddset(&set, SIGCHLD);
922 	sigprocmask(SIG_BLOCK, &set, &oset);
923 
924 	if (child_pid != -1)
925 		kill(child_pid, SIGTERM);
926 
927 	sigprocmask(SIG_SETMASK, &oset, NULL);
928 
929 	if (signr == -1)
930 		return;
931 
932 	signal(signr, SIG_DFL);
933 	kill(getpid(), signr);
934 }
935 
936 static int stat__set_big_num(const struct option *opt __maybe_unused,
937 			     const char *s __maybe_unused, int unset)
938 {
939 	big_num_opt = unset ? 0 : 1;
940 	return 0;
941 }
942 
943 static int perf_stat_init_aggr_mode(void)
944 {
945 	switch (stat_config.aggr_mode) {
946 	case AGGR_SOCKET:
947 		if (cpu_map__build_socket_map(evsel_list->cpus, &aggr_map)) {
948 			perror("cannot build socket map");
949 			return -1;
950 		}
951 		aggr_get_id = cpu_map__get_socket;
952 		break;
953 	case AGGR_CORE:
954 		if (cpu_map__build_core_map(evsel_list->cpus, &aggr_map)) {
955 			perror("cannot build core map");
956 			return -1;
957 		}
958 		aggr_get_id = cpu_map__get_core;
959 		break;
960 	case AGGR_NONE:
961 	case AGGR_GLOBAL:
962 	case AGGR_THREAD:
963 	default:
964 		break;
965 	}
966 	return 0;
967 }
968 
969 /*
970  * Add default attributes, if there were no attributes specified or
971  * if -d/--detailed, -d -d or -d -d -d is used:
972  */
973 static int add_default_attributes(void)
974 {
975 	struct perf_event_attr default_attrs[] = {
976 
977   { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_TASK_CLOCK		},
978   { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES	},
979   { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CPU_MIGRATIONS		},
980   { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_PAGE_FAULTS		},
981 
982   { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES		},
983   { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_STALLED_CYCLES_FRONTEND	},
984   { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_STALLED_CYCLES_BACKEND	},
985   { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_INSTRUCTIONS		},
986   { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS	},
987   { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_MISSES		},
988 
989 };
990 
991 /*
992  * Detailed stats (-d), covering the L1 and last level data caches:
993  */
994 	struct perf_event_attr detailed_attrs[] = {
995 
996   { .type = PERF_TYPE_HW_CACHE,
997     .config =
998 	 PERF_COUNT_HW_CACHE_L1D		<<  0  |
999 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1000 	(PERF_COUNT_HW_CACHE_RESULT_ACCESS	<< 16)				},
1001 
1002   { .type = PERF_TYPE_HW_CACHE,
1003     .config =
1004 	 PERF_COUNT_HW_CACHE_L1D		<<  0  |
1005 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1006 	(PERF_COUNT_HW_CACHE_RESULT_MISS	<< 16)				},
1007 
1008   { .type = PERF_TYPE_HW_CACHE,
1009     .config =
1010 	 PERF_COUNT_HW_CACHE_LL			<<  0  |
1011 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1012 	(PERF_COUNT_HW_CACHE_RESULT_ACCESS	<< 16)				},
1013 
1014   { .type = PERF_TYPE_HW_CACHE,
1015     .config =
1016 	 PERF_COUNT_HW_CACHE_LL			<<  0  |
1017 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1018 	(PERF_COUNT_HW_CACHE_RESULT_MISS	<< 16)				},
1019 };
1020 
1021 /*
1022  * Very detailed stats (-d -d), covering the instruction cache and the TLB caches:
1023  */
1024 	struct perf_event_attr very_detailed_attrs[] = {
1025 
1026   { .type = PERF_TYPE_HW_CACHE,
1027     .config =
1028 	 PERF_COUNT_HW_CACHE_L1I		<<  0  |
1029 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1030 	(PERF_COUNT_HW_CACHE_RESULT_ACCESS	<< 16)				},
1031 
1032   { .type = PERF_TYPE_HW_CACHE,
1033     .config =
1034 	 PERF_COUNT_HW_CACHE_L1I		<<  0  |
1035 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1036 	(PERF_COUNT_HW_CACHE_RESULT_MISS	<< 16)				},
1037 
1038   { .type = PERF_TYPE_HW_CACHE,
1039     .config =
1040 	 PERF_COUNT_HW_CACHE_DTLB		<<  0  |
1041 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1042 	(PERF_COUNT_HW_CACHE_RESULT_ACCESS	<< 16)				},
1043 
1044   { .type = PERF_TYPE_HW_CACHE,
1045     .config =
1046 	 PERF_COUNT_HW_CACHE_DTLB		<<  0  |
1047 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1048 	(PERF_COUNT_HW_CACHE_RESULT_MISS	<< 16)				},
1049 
1050   { .type = PERF_TYPE_HW_CACHE,
1051     .config =
1052 	 PERF_COUNT_HW_CACHE_ITLB		<<  0  |
1053 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1054 	(PERF_COUNT_HW_CACHE_RESULT_ACCESS	<< 16)				},
1055 
1056   { .type = PERF_TYPE_HW_CACHE,
1057     .config =
1058 	 PERF_COUNT_HW_CACHE_ITLB		<<  0  |
1059 	(PERF_COUNT_HW_CACHE_OP_READ		<<  8) |
1060 	(PERF_COUNT_HW_CACHE_RESULT_MISS	<< 16)				},
1061 
1062 };
1063 
1064 /*
1065  * Very, very detailed stats (-d -d -d), adding prefetch events:
1066  */
1067 	struct perf_event_attr very_very_detailed_attrs[] = {
1068 
1069   { .type = PERF_TYPE_HW_CACHE,
1070     .config =
1071 	 PERF_COUNT_HW_CACHE_L1D		<<  0  |
1072 	(PERF_COUNT_HW_CACHE_OP_PREFETCH	<<  8) |
1073 	(PERF_COUNT_HW_CACHE_RESULT_ACCESS	<< 16)				},
1074 
1075   { .type = PERF_TYPE_HW_CACHE,
1076     .config =
1077 	 PERF_COUNT_HW_CACHE_L1D		<<  0  |
1078 	(PERF_COUNT_HW_CACHE_OP_PREFETCH	<<  8) |
1079 	(PERF_COUNT_HW_CACHE_RESULT_MISS	<< 16)				},
1080 };
1081 
1082 	/* Set attrs if no event is selected and !null_run: */
1083 	if (null_run)
1084 		return 0;
1085 
1086 	if (transaction_run) {
1087 		int err;
1088 		if (pmu_have_event("cpu", "cycles-ct") &&
1089 		    pmu_have_event("cpu", "el-start"))
1090 			err = parse_events(evsel_list, transaction_attrs, NULL);
1091 		else
1092 			err = parse_events(evsel_list, transaction_limited_attrs, NULL);
1093 		if (err) {
1094 			fprintf(stderr, "Cannot set up transaction events\n");
1095 			return -1;
1096 		}
1097 		return 0;
1098 	}
1099 
1100 	if (!evsel_list->nr_entries) {
1101 		if (perf_evlist__add_default_attrs(evsel_list, default_attrs) < 0)
1102 			return -1;
1103 	}
1104 
1105 	/* Detailed events get appended to the event list: */
1106 
1107 	if (detailed_run <  1)
1108 		return 0;
1109 
1110 	/* Append detailed run extra attributes: */
1111 	if (perf_evlist__add_default_attrs(evsel_list, detailed_attrs) < 0)
1112 		return -1;
1113 
1114 	if (detailed_run < 2)
1115 		return 0;
1116 
1117 	/* Append very detailed run extra attributes: */
1118 	if (perf_evlist__add_default_attrs(evsel_list, very_detailed_attrs) < 0)
1119 		return -1;
1120 
1121 	if (detailed_run < 3)
1122 		return 0;
1123 
1124 	/* Append very, very detailed run extra attributes: */
1125 	return perf_evlist__add_default_attrs(evsel_list, very_very_detailed_attrs);
1126 }
1127 
1128 int cmd_stat(int argc, const char **argv, const char *prefix __maybe_unused)
1129 {
1130 	bool append_file = false;
1131 	int output_fd = 0;
1132 	const char *output_name	= NULL;
1133 	const struct option options[] = {
1134 	OPT_BOOLEAN('T', "transaction", &transaction_run,
1135 		    "hardware transaction statistics"),
1136 	OPT_CALLBACK('e', "event", &evsel_list, "event",
1137 		     "event selector. use 'perf list' to list available events",
1138 		     parse_events_option),
1139 	OPT_CALLBACK(0, "filter", &evsel_list, "filter",
1140 		     "event filter", parse_filter),
1141 	OPT_BOOLEAN('i', "no-inherit", &no_inherit,
1142 		    "child tasks do not inherit counters"),
1143 	OPT_STRING('p', "pid", &target.pid, "pid",
1144 		   "stat events on existing process id"),
1145 	OPT_STRING('t', "tid", &target.tid, "tid",
1146 		   "stat events on existing thread id"),
1147 	OPT_BOOLEAN('a', "all-cpus", &target.system_wide,
1148 		    "system-wide collection from all CPUs"),
1149 	OPT_BOOLEAN('g', "group", &group,
1150 		    "put the counters into a counter group"),
1151 	OPT_BOOLEAN('c', "scale", &stat_config.scale, "scale/normalize counters"),
1152 	OPT_INCR('v', "verbose", &verbose,
1153 		    "be more verbose (show counter open errors, etc)"),
1154 	OPT_INTEGER('r', "repeat", &run_count,
1155 		    "repeat command and print average + stddev (max: 100, forever: 0)"),
1156 	OPT_BOOLEAN('n', "null", &null_run,
1157 		    "null run - dont start any counters"),
1158 	OPT_INCR('d', "detailed", &detailed_run,
1159 		    "detailed run - start a lot of events"),
1160 	OPT_BOOLEAN('S', "sync", &sync_run,
1161 		    "call sync() before starting a run"),
1162 	OPT_CALLBACK_NOOPT('B', "big-num", NULL, NULL,
1163 			   "print large numbers with thousands\' separators",
1164 			   stat__set_big_num),
1165 	OPT_STRING('C', "cpu", &target.cpu_list, "cpu",
1166 		    "list of cpus to monitor in system-wide"),
1167 	OPT_SET_UINT('A', "no-aggr", &stat_config.aggr_mode,
1168 		    "disable CPU count aggregation", AGGR_NONE),
1169 	OPT_STRING('x', "field-separator", &csv_sep, "separator",
1170 		   "print counts with custom separator"),
1171 	OPT_CALLBACK('G', "cgroup", &evsel_list, "name",
1172 		     "monitor event in cgroup name only", parse_cgroups),
1173 	OPT_STRING('o', "output", &output_name, "file", "output file name"),
1174 	OPT_BOOLEAN(0, "append", &append_file, "append to the output file"),
1175 	OPT_INTEGER(0, "log-fd", &output_fd,
1176 		    "log output to fd, instead of stderr"),
1177 	OPT_STRING(0, "pre", &pre_cmd, "command",
1178 			"command to run prior to the measured command"),
1179 	OPT_STRING(0, "post", &post_cmd, "command",
1180 			"command to run after to the measured command"),
1181 	OPT_UINTEGER('I', "interval-print", &stat_config.interval,
1182 		    "print counts at regular interval in ms (>= 100)"),
1183 	OPT_SET_UINT(0, "per-socket", &stat_config.aggr_mode,
1184 		     "aggregate counts per processor socket", AGGR_SOCKET),
1185 	OPT_SET_UINT(0, "per-core", &stat_config.aggr_mode,
1186 		     "aggregate counts per physical processor core", AGGR_CORE),
1187 	OPT_SET_UINT(0, "per-thread", &stat_config.aggr_mode,
1188 		     "aggregate counts per thread", AGGR_THREAD),
1189 	OPT_UINTEGER('D', "delay", &initial_delay,
1190 		     "ms to wait before starting measurement after program start"),
1191 	OPT_END()
1192 	};
1193 	const char * const stat_usage[] = {
1194 		"perf stat [<options>] [<command>]",
1195 		NULL
1196 	};
1197 	int status = -EINVAL, run_idx;
1198 	const char *mode;
1199 	FILE *output = stderr;
1200 	unsigned int interval;
1201 
1202 	setlocale(LC_ALL, "");
1203 
1204 	evsel_list = perf_evlist__new();
1205 	if (evsel_list == NULL)
1206 		return -ENOMEM;
1207 
1208 	argc = parse_options(argc, argv, options, stat_usage,
1209 		PARSE_OPT_STOP_AT_NON_OPTION);
1210 
1211 	interval = stat_config.interval;
1212 
1213 	if (output_name && strcmp(output_name, "-"))
1214 		output = NULL;
1215 
1216 	if (output_name && output_fd) {
1217 		fprintf(stderr, "cannot use both --output and --log-fd\n");
1218 		parse_options_usage(stat_usage, options, "o", 1);
1219 		parse_options_usage(NULL, options, "log-fd", 0);
1220 		goto out;
1221 	}
1222 
1223 	if (output_fd < 0) {
1224 		fprintf(stderr, "argument to --log-fd must be a > 0\n");
1225 		parse_options_usage(stat_usage, options, "log-fd", 0);
1226 		goto out;
1227 	}
1228 
1229 	if (!output) {
1230 		struct timespec tm;
1231 		mode = append_file ? "a" : "w";
1232 
1233 		output = fopen(output_name, mode);
1234 		if (!output) {
1235 			perror("failed to create output file");
1236 			return -1;
1237 		}
1238 		clock_gettime(CLOCK_REALTIME, &tm);
1239 		fprintf(output, "# started on %s\n", ctime(&tm.tv_sec));
1240 	} else if (output_fd > 0) {
1241 		mode = append_file ? "a" : "w";
1242 		output = fdopen(output_fd, mode);
1243 		if (!output) {
1244 			perror("Failed opening logfd");
1245 			return -errno;
1246 		}
1247 	}
1248 
1249 	stat_config.output = output;
1250 
1251 	if (csv_sep) {
1252 		csv_output = true;
1253 		if (!strcmp(csv_sep, "\\t"))
1254 			csv_sep = "\t";
1255 	} else
1256 		csv_sep = DEFAULT_SEPARATOR;
1257 
1258 	/*
1259 	 * let the spreadsheet do the pretty-printing
1260 	 */
1261 	if (csv_output) {
1262 		/* User explicitly passed -B? */
1263 		if (big_num_opt == 1) {
1264 			fprintf(stderr, "-B option not supported with -x\n");
1265 			parse_options_usage(stat_usage, options, "B", 1);
1266 			parse_options_usage(NULL, options, "x", 1);
1267 			goto out;
1268 		} else /* Nope, so disable big number formatting */
1269 			big_num = false;
1270 	} else if (big_num_opt == 0) /* User passed --no-big-num */
1271 		big_num = false;
1272 
1273 	if (!argc && target__none(&target))
1274 		usage_with_options(stat_usage, options);
1275 
1276 	if (run_count < 0) {
1277 		pr_err("Run count must be a positive number\n");
1278 		parse_options_usage(stat_usage, options, "r", 1);
1279 		goto out;
1280 	} else if (run_count == 0) {
1281 		forever = true;
1282 		run_count = 1;
1283 	}
1284 
1285 	if ((stat_config.aggr_mode == AGGR_THREAD) && !target__has_task(&target)) {
1286 		fprintf(stderr, "The --per-thread option is only available "
1287 			"when monitoring via -p -t options.\n");
1288 		parse_options_usage(NULL, options, "p", 1);
1289 		parse_options_usage(NULL, options, "t", 1);
1290 		goto out;
1291 	}
1292 
1293 	/*
1294 	 * no_aggr, cgroup are for system-wide only
1295 	 * --per-thread is aggregated per thread, we dont mix it with cpu mode
1296 	 */
1297 	if (((stat_config.aggr_mode != AGGR_GLOBAL &&
1298 	      stat_config.aggr_mode != AGGR_THREAD) || nr_cgroups) &&
1299 	    !target__has_cpu(&target)) {
1300 		fprintf(stderr, "both cgroup and no-aggregation "
1301 			"modes only available in system-wide mode\n");
1302 
1303 		parse_options_usage(stat_usage, options, "G", 1);
1304 		parse_options_usage(NULL, options, "A", 1);
1305 		parse_options_usage(NULL, options, "a", 1);
1306 		goto out;
1307 	}
1308 
1309 	if (add_default_attributes())
1310 		goto out;
1311 
1312 	target__validate(&target);
1313 
1314 	if (perf_evlist__create_maps(evsel_list, &target) < 0) {
1315 		if (target__has_task(&target)) {
1316 			pr_err("Problems finding threads of monitor\n");
1317 			parse_options_usage(stat_usage, options, "p", 1);
1318 			parse_options_usage(NULL, options, "t", 1);
1319 		} else if (target__has_cpu(&target)) {
1320 			perror("failed to parse CPUs map");
1321 			parse_options_usage(stat_usage, options, "C", 1);
1322 			parse_options_usage(NULL, options, "a", 1);
1323 		}
1324 		goto out;
1325 	}
1326 
1327 	/*
1328 	 * Initialize thread_map with comm names,
1329 	 * so we could print it out on output.
1330 	 */
1331 	if (stat_config.aggr_mode == AGGR_THREAD)
1332 		thread_map__read_comms(evsel_list->threads);
1333 
1334 	if (interval && interval < 100) {
1335 		pr_err("print interval must be >= 100ms\n");
1336 		parse_options_usage(stat_usage, options, "I", 1);
1337 		goto out;
1338 	}
1339 
1340 	if (perf_evlist__alloc_stats(evsel_list, interval))
1341 		goto out;
1342 
1343 	if (perf_stat_init_aggr_mode())
1344 		goto out;
1345 
1346 	/*
1347 	 * We dont want to block the signals - that would cause
1348 	 * child tasks to inherit that and Ctrl-C would not work.
1349 	 * What we want is for Ctrl-C to work in the exec()-ed
1350 	 * task, but being ignored by perf stat itself:
1351 	 */
1352 	atexit(sig_atexit);
1353 	if (!forever)
1354 		signal(SIGINT,  skip_signal);
1355 	signal(SIGCHLD, skip_signal);
1356 	signal(SIGALRM, skip_signal);
1357 	signal(SIGABRT, skip_signal);
1358 
1359 	status = 0;
1360 	for (run_idx = 0; forever || run_idx < run_count; run_idx++) {
1361 		if (run_count != 1 && verbose)
1362 			fprintf(output, "[ perf stat: executing run #%d ... ]\n",
1363 				run_idx + 1);
1364 
1365 		status = run_perf_stat(argc, argv);
1366 		if (forever && status != -1) {
1367 			print_counters(NULL, argc, argv);
1368 			perf_stat__reset_stats();
1369 		}
1370 	}
1371 
1372 	if (!forever && status != -1 && !interval)
1373 		print_counters(NULL, argc, argv);
1374 
1375 	perf_evlist__free_stats(evsel_list);
1376 out:
1377 	perf_evlist__delete(evsel_list);
1378 	return status;
1379 }
1380