xref: /openbmc/linux/tools/perf/builtin-record.c (revision 03cb0503)
1 /*
2  * builtin-record.c
3  *
4  * Builtin record command: Record the profile of a workload
5  * (or a CPU, or a PID) into the perf.data output file - for
6  * later analysis via perf report.
7  */
8 #include "builtin.h"
9 
10 #include "perf.h"
11 
12 #include "util/build-id.h"
13 #include "util/util.h"
14 #include "util/parse-options.h"
15 #include "util/parse-events.h"
16 
17 #include "util/callchain.h"
18 #include "util/cgroup.h"
19 #include "util/header.h"
20 #include "util/event.h"
21 #include "util/evlist.h"
22 #include "util/evsel.h"
23 #include "util/debug.h"
24 #include "util/session.h"
25 #include "util/tool.h"
26 #include "util/symbol.h"
27 #include "util/cpumap.h"
28 #include "util/thread_map.h"
29 #include "util/data.h"
30 
31 #include <unistd.h>
32 #include <sched.h>
33 #include <sys/mman.h>
34 
35 
36 struct record {
37 	struct perf_tool	tool;
38 	struct record_opts	opts;
39 	u64			bytes_written;
40 	struct perf_data_file	file;
41 	struct perf_evlist	*evlist;
42 	struct perf_session	*session;
43 	const char		*progname;
44 	int			realtime_prio;
45 	bool			no_buildid;
46 	bool			no_buildid_cache;
47 	long			samples;
48 };
49 
50 static int record__write(struct record *rec, void *bf, size_t size)
51 {
52 	if (perf_data_file__write(rec->session->file, bf, size) < 0) {
53 		pr_err("failed to write perf data, error: %m\n");
54 		return -1;
55 	}
56 
57 	rec->bytes_written += size;
58 	return 0;
59 }
60 
61 static int process_synthesized_event(struct perf_tool *tool,
62 				     union perf_event *event,
63 				     struct perf_sample *sample __maybe_unused,
64 				     struct machine *machine __maybe_unused)
65 {
66 	struct record *rec = container_of(tool, struct record, tool);
67 	return record__write(rec, event, event->header.size);
68 }
69 
70 static int record__mmap_read(struct record *rec, int idx)
71 {
72 	struct perf_mmap *md = &rec->evlist->mmap[idx];
73 	u64 head = perf_mmap__read_head(md);
74 	u64 old = md->prev;
75 	unsigned char *data = md->base + page_size;
76 	unsigned long size;
77 	void *buf;
78 	int rc = 0;
79 
80 	if (old == head)
81 		return 0;
82 
83 	rec->samples++;
84 
85 	size = head - old;
86 
87 	if ((old & md->mask) + size != (head & md->mask)) {
88 		buf = &data[old & md->mask];
89 		size = md->mask + 1 - (old & md->mask);
90 		old += size;
91 
92 		if (record__write(rec, buf, size) < 0) {
93 			rc = -1;
94 			goto out;
95 		}
96 	}
97 
98 	buf = &data[old & md->mask];
99 	size = head - old;
100 	old += size;
101 
102 	if (record__write(rec, buf, size) < 0) {
103 		rc = -1;
104 		goto out;
105 	}
106 
107 	md->prev = old;
108 	perf_evlist__mmap_consume(rec->evlist, idx);
109 out:
110 	return rc;
111 }
112 
113 static volatile int done = 0;
114 static volatile int signr = -1;
115 static volatile int child_finished = 0;
116 
117 static void sig_handler(int sig)
118 {
119 	if (sig == SIGCHLD)
120 		child_finished = 1;
121 	else
122 		signr = sig;
123 
124 	done = 1;
125 }
126 
127 static void record__sig_exit(void)
128 {
129 	if (signr == -1)
130 		return;
131 
132 	signal(signr, SIG_DFL);
133 	raise(signr);
134 }
135 
136 static int record__open(struct record *rec)
137 {
138 	char msg[512];
139 	struct perf_evsel *pos;
140 	struct perf_evlist *evlist = rec->evlist;
141 	struct perf_session *session = rec->session;
142 	struct record_opts *opts = &rec->opts;
143 	int rc = 0;
144 
145 	perf_evlist__config(evlist, opts);
146 
147 	evlist__for_each(evlist, pos) {
148 try_again:
149 		if (perf_evsel__open(pos, evlist->cpus, evlist->threads) < 0) {
150 			if (perf_evsel__fallback(pos, errno, msg, sizeof(msg))) {
151 				if (verbose)
152 					ui__warning("%s\n", msg);
153 				goto try_again;
154 			}
155 
156 			rc = -errno;
157 			perf_evsel__open_strerror(pos, &opts->target,
158 						  errno, msg, sizeof(msg));
159 			ui__error("%s\n", msg);
160 			goto out;
161 		}
162 	}
163 
164 	if (perf_evlist__apply_filters(evlist, &pos)) {
165 		error("failed to set filter \"%s\" on event %s with %d (%s)\n",
166 			pos->filter, perf_evsel__name(pos), errno,
167 			strerror_r(errno, msg, sizeof(msg)));
168 		rc = -1;
169 		goto out;
170 	}
171 
172 	if (perf_evlist__mmap(evlist, opts->mmap_pages, false) < 0) {
173 		if (errno == EPERM) {
174 			pr_err("Permission error mapping pages.\n"
175 			       "Consider increasing "
176 			       "/proc/sys/kernel/perf_event_mlock_kb,\n"
177 			       "or try again with a smaller value of -m/--mmap_pages.\n"
178 			       "(current value: %u)\n", opts->mmap_pages);
179 			rc = -errno;
180 		} else {
181 			pr_err("failed to mmap with %d (%s)\n", errno,
182 				strerror_r(errno, msg, sizeof(msg)));
183 			rc = -errno;
184 		}
185 		goto out;
186 	}
187 
188 	session->evlist = evlist;
189 	perf_session__set_id_hdr_size(session);
190 out:
191 	return rc;
192 }
193 
194 static int process_sample_event(struct perf_tool *tool,
195 				union perf_event *event,
196 				struct perf_sample *sample,
197 				struct perf_evsel *evsel,
198 				struct machine *machine)
199 {
200 	struct record *rec = container_of(tool, struct record, tool);
201 
202 	rec->samples++;
203 
204 	return build_id__mark_dso_hit(tool, event, sample, evsel, machine);
205 }
206 
207 static int process_buildids(struct record *rec)
208 {
209 	struct perf_data_file *file  = &rec->file;
210 	struct perf_session *session = rec->session;
211 
212 	u64 size = lseek(perf_data_file__fd(file), 0, SEEK_CUR);
213 	if (size == 0)
214 		return 0;
215 
216 	file->size = size;
217 
218 	/*
219 	 * During this process, it'll load kernel map and replace the
220 	 * dso->long_name to a real pathname it found.  In this case
221 	 * we prefer the vmlinux path like
222 	 *   /lib/modules/3.16.4/build/vmlinux
223 	 *
224 	 * rather than build-id path (in debug directory).
225 	 *   $HOME/.debug/.build-id/f0/6e17aa50adf4d00b88925e03775de107611551
226 	 */
227 	symbol_conf.ignore_vmlinux_buildid = true;
228 
229 	return perf_session__process_events(session);
230 }
231 
232 static void perf_event__synthesize_guest_os(struct machine *machine, void *data)
233 {
234 	int err;
235 	struct perf_tool *tool = data;
236 	/*
237 	 *As for guest kernel when processing subcommand record&report,
238 	 *we arrange module mmap prior to guest kernel mmap and trigger
239 	 *a preload dso because default guest module symbols are loaded
240 	 *from guest kallsyms instead of /lib/modules/XXX/XXX. This
241 	 *method is used to avoid symbol missing when the first addr is
242 	 *in module instead of in guest kernel.
243 	 */
244 	err = perf_event__synthesize_modules(tool, process_synthesized_event,
245 					     machine);
246 	if (err < 0)
247 		pr_err("Couldn't record guest kernel [%d]'s reference"
248 		       " relocation symbol.\n", machine->pid);
249 
250 	/*
251 	 * We use _stext for guest kernel because guest kernel's /proc/kallsyms
252 	 * have no _text sometimes.
253 	 */
254 	err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
255 						 machine);
256 	if (err < 0)
257 		pr_err("Couldn't record guest kernel [%d]'s reference"
258 		       " relocation symbol.\n", machine->pid);
259 }
260 
261 static struct perf_event_header finished_round_event = {
262 	.size = sizeof(struct perf_event_header),
263 	.type = PERF_RECORD_FINISHED_ROUND,
264 };
265 
266 static int record__mmap_read_all(struct record *rec)
267 {
268 	u64 bytes_written = rec->bytes_written;
269 	int i;
270 	int rc = 0;
271 
272 	for (i = 0; i < rec->evlist->nr_mmaps; i++) {
273 		if (rec->evlist->mmap[i].base) {
274 			if (record__mmap_read(rec, i) != 0) {
275 				rc = -1;
276 				goto out;
277 			}
278 		}
279 	}
280 
281 	/*
282 	 * Mark the round finished in case we wrote
283 	 * at least one event.
284 	 */
285 	if (bytes_written != rec->bytes_written)
286 		rc = record__write(rec, &finished_round_event, sizeof(finished_round_event));
287 
288 out:
289 	return rc;
290 }
291 
292 static void record__init_features(struct record *rec)
293 {
294 	struct perf_session *session = rec->session;
295 	int feat;
296 
297 	for (feat = HEADER_FIRST_FEATURE; feat < HEADER_LAST_FEATURE; feat++)
298 		perf_header__set_feat(&session->header, feat);
299 
300 	if (rec->no_buildid)
301 		perf_header__clear_feat(&session->header, HEADER_BUILD_ID);
302 
303 	if (!have_tracepoints(&rec->evlist->entries))
304 		perf_header__clear_feat(&session->header, HEADER_TRACING_DATA);
305 
306 	if (!rec->opts.branch_stack)
307 		perf_header__clear_feat(&session->header, HEADER_BRANCH_STACK);
308 }
309 
310 static volatile int workload_exec_errno;
311 
312 /*
313  * perf_evlist__prepare_workload will send a SIGUSR1
314  * if the fork fails, since we asked by setting its
315  * want_signal to true.
316  */
317 static void workload_exec_failed_signal(int signo __maybe_unused,
318 					siginfo_t *info,
319 					void *ucontext __maybe_unused)
320 {
321 	workload_exec_errno = info->si_value.sival_int;
322 	done = 1;
323 	child_finished = 1;
324 }
325 
326 static int __cmd_record(struct record *rec, int argc, const char **argv)
327 {
328 	int err;
329 	int status = 0;
330 	unsigned long waking = 0;
331 	const bool forks = argc > 0;
332 	struct machine *machine;
333 	struct perf_tool *tool = &rec->tool;
334 	struct record_opts *opts = &rec->opts;
335 	struct perf_data_file *file = &rec->file;
336 	struct perf_session *session;
337 	bool disabled = false, draining = false;
338 	int fd;
339 
340 	rec->progname = argv[0];
341 
342 	atexit(record__sig_exit);
343 	signal(SIGCHLD, sig_handler);
344 	signal(SIGINT, sig_handler);
345 	signal(SIGTERM, sig_handler);
346 
347 	session = perf_session__new(file, false, tool);
348 	if (session == NULL) {
349 		pr_err("Perf session creation failed.\n");
350 		return -1;
351 	}
352 
353 	fd = perf_data_file__fd(file);
354 	rec->session = session;
355 
356 	record__init_features(rec);
357 
358 	if (forks) {
359 		err = perf_evlist__prepare_workload(rec->evlist, &opts->target,
360 						    argv, file->is_pipe,
361 						    workload_exec_failed_signal);
362 		if (err < 0) {
363 			pr_err("Couldn't run the workload!\n");
364 			status = err;
365 			goto out_delete_session;
366 		}
367 	}
368 
369 	if (record__open(rec) != 0) {
370 		err = -1;
371 		goto out_child;
372 	}
373 
374 	if (!rec->evlist->nr_groups)
375 		perf_header__clear_feat(&session->header, HEADER_GROUP_DESC);
376 
377 	if (file->is_pipe) {
378 		err = perf_header__write_pipe(fd);
379 		if (err < 0)
380 			goto out_child;
381 	} else {
382 		err = perf_session__write_header(session, rec->evlist, fd, false);
383 		if (err < 0)
384 			goto out_child;
385 	}
386 
387 	if (!rec->no_buildid
388 	    && !perf_header__has_feat(&session->header, HEADER_BUILD_ID)) {
389 		pr_err("Couldn't generate buildids. "
390 		       "Use --no-buildid to profile anyway.\n");
391 		err = -1;
392 		goto out_child;
393 	}
394 
395 	machine = &session->machines.host;
396 
397 	if (file->is_pipe) {
398 		err = perf_event__synthesize_attrs(tool, session,
399 						   process_synthesized_event);
400 		if (err < 0) {
401 			pr_err("Couldn't synthesize attrs.\n");
402 			goto out_child;
403 		}
404 
405 		if (have_tracepoints(&rec->evlist->entries)) {
406 			/*
407 			 * FIXME err <= 0 here actually means that
408 			 * there were no tracepoints so its not really
409 			 * an error, just that we don't need to
410 			 * synthesize anything.  We really have to
411 			 * return this more properly and also
412 			 * propagate errors that now are calling die()
413 			 */
414 			err = perf_event__synthesize_tracing_data(tool,	fd, rec->evlist,
415 								  process_synthesized_event);
416 			if (err <= 0) {
417 				pr_err("Couldn't record tracing data.\n");
418 				goto out_child;
419 			}
420 			rec->bytes_written += err;
421 		}
422 	}
423 
424 	err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
425 						 machine);
426 	if (err < 0)
427 		pr_err("Couldn't record kernel reference relocation symbol\n"
428 		       "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
429 		       "Check /proc/kallsyms permission or run as root.\n");
430 
431 	err = perf_event__synthesize_modules(tool, process_synthesized_event,
432 					     machine);
433 	if (err < 0)
434 		pr_err("Couldn't record kernel module information.\n"
435 		       "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
436 		       "Check /proc/modules permission or run as root.\n");
437 
438 	if (perf_guest) {
439 		machines__process_guests(&session->machines,
440 					 perf_event__synthesize_guest_os, tool);
441 	}
442 
443 	err = __machine__synthesize_threads(machine, tool, &opts->target, rec->evlist->threads,
444 					    process_synthesized_event, opts->sample_address);
445 	if (err != 0)
446 		goto out_child;
447 
448 	if (rec->realtime_prio) {
449 		struct sched_param param;
450 
451 		param.sched_priority = rec->realtime_prio;
452 		if (sched_setscheduler(0, SCHED_FIFO, &param)) {
453 			pr_err("Could not set realtime priority.\n");
454 			err = -1;
455 			goto out_child;
456 		}
457 	}
458 
459 	/*
460 	 * When perf is starting the traced process, all the events
461 	 * (apart from group members) have enable_on_exec=1 set,
462 	 * so don't spoil it by prematurely enabling them.
463 	 */
464 	if (!target__none(&opts->target) && !opts->initial_delay)
465 		perf_evlist__enable(rec->evlist);
466 
467 	/*
468 	 * Let the child rip
469 	 */
470 	if (forks)
471 		perf_evlist__start_workload(rec->evlist);
472 
473 	if (opts->initial_delay) {
474 		usleep(opts->initial_delay * 1000);
475 		perf_evlist__enable(rec->evlist);
476 	}
477 
478 	for (;;) {
479 		int hits = rec->samples;
480 
481 		if (record__mmap_read_all(rec) < 0) {
482 			err = -1;
483 			goto out_child;
484 		}
485 
486 		if (hits == rec->samples) {
487 			if (done || draining)
488 				break;
489 			err = perf_evlist__poll(rec->evlist, -1);
490 			/*
491 			 * Propagate error, only if there's any. Ignore positive
492 			 * number of returned events and interrupt error.
493 			 */
494 			if (err > 0 || (err < 0 && errno == EINTR))
495 				err = 0;
496 			waking++;
497 
498 			if (perf_evlist__filter_pollfd(rec->evlist, POLLERR | POLLHUP) == 0)
499 				draining = true;
500 		}
501 
502 		/*
503 		 * When perf is starting the traced process, at the end events
504 		 * die with the process and we wait for that. Thus no need to
505 		 * disable events in this case.
506 		 */
507 		if (done && !disabled && !target__none(&opts->target)) {
508 			perf_evlist__disable(rec->evlist);
509 			disabled = true;
510 		}
511 	}
512 
513 	if (forks && workload_exec_errno) {
514 		char msg[STRERR_BUFSIZE];
515 		const char *emsg = strerror_r(workload_exec_errno, msg, sizeof(msg));
516 		pr_err("Workload failed: %s\n", emsg);
517 		err = -1;
518 		goto out_child;
519 	}
520 
521 	if (!quiet)
522 		fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
523 
524 out_child:
525 	if (forks) {
526 		int exit_status;
527 
528 		if (!child_finished)
529 			kill(rec->evlist->workload.pid, SIGTERM);
530 
531 		wait(&exit_status);
532 
533 		if (err < 0)
534 			status = err;
535 		else if (WIFEXITED(exit_status))
536 			status = WEXITSTATUS(exit_status);
537 		else if (WIFSIGNALED(exit_status))
538 			signr = WTERMSIG(exit_status);
539 	} else
540 		status = err;
541 
542 	/* this will be recalculated during process_buildids() */
543 	rec->samples = 0;
544 
545 	if (!err && !file->is_pipe) {
546 		rec->session->header.data_size += rec->bytes_written;
547 
548 		if (!rec->no_buildid)
549 			process_buildids(rec);
550 		perf_session__write_header(rec->session, rec->evlist, fd, true);
551 	}
552 
553 	if (!err && !quiet) {
554 		char samples[128];
555 
556 		if (rec->samples)
557 			scnprintf(samples, sizeof(samples),
558 				  " (%" PRIu64 " samples)", rec->samples);
559 		else
560 			samples[0] = '\0';
561 
562 		fprintf(stderr,	"[ perf record: Captured and wrote %.3f MB %s%s ]\n",
563 			perf_data_file__size(file) / 1024.0 / 1024.0,
564 			file->path, samples);
565 	}
566 
567 out_delete_session:
568 	perf_session__delete(session);
569 	return status;
570 }
571 
572 #define BRANCH_OPT(n, m) \
573 	{ .name = n, .mode = (m) }
574 
575 #define BRANCH_END { .name = NULL }
576 
577 struct branch_mode {
578 	const char *name;
579 	int mode;
580 };
581 
582 static const struct branch_mode branch_modes[] = {
583 	BRANCH_OPT("u", PERF_SAMPLE_BRANCH_USER),
584 	BRANCH_OPT("k", PERF_SAMPLE_BRANCH_KERNEL),
585 	BRANCH_OPT("hv", PERF_SAMPLE_BRANCH_HV),
586 	BRANCH_OPT("any", PERF_SAMPLE_BRANCH_ANY),
587 	BRANCH_OPT("any_call", PERF_SAMPLE_BRANCH_ANY_CALL),
588 	BRANCH_OPT("any_ret", PERF_SAMPLE_BRANCH_ANY_RETURN),
589 	BRANCH_OPT("ind_call", PERF_SAMPLE_BRANCH_IND_CALL),
590 	BRANCH_OPT("abort_tx", PERF_SAMPLE_BRANCH_ABORT_TX),
591 	BRANCH_OPT("in_tx", PERF_SAMPLE_BRANCH_IN_TX),
592 	BRANCH_OPT("no_tx", PERF_SAMPLE_BRANCH_NO_TX),
593 	BRANCH_OPT("cond", PERF_SAMPLE_BRANCH_COND),
594 	BRANCH_END
595 };
596 
597 static int
598 parse_branch_stack(const struct option *opt, const char *str, int unset)
599 {
600 #define ONLY_PLM \
601 	(PERF_SAMPLE_BRANCH_USER	|\
602 	 PERF_SAMPLE_BRANCH_KERNEL	|\
603 	 PERF_SAMPLE_BRANCH_HV)
604 
605 	uint64_t *mode = (uint64_t *)opt->value;
606 	const struct branch_mode *br;
607 	char *s, *os = NULL, *p;
608 	int ret = -1;
609 
610 	if (unset)
611 		return 0;
612 
613 	/*
614 	 * cannot set it twice, -b + --branch-filter for instance
615 	 */
616 	if (*mode)
617 		return -1;
618 
619 	/* str may be NULL in case no arg is passed to -b */
620 	if (str) {
621 		/* because str is read-only */
622 		s = os = strdup(str);
623 		if (!s)
624 			return -1;
625 
626 		for (;;) {
627 			p = strchr(s, ',');
628 			if (p)
629 				*p = '\0';
630 
631 			for (br = branch_modes; br->name; br++) {
632 				if (!strcasecmp(s, br->name))
633 					break;
634 			}
635 			if (!br->name) {
636 				ui__warning("unknown branch filter %s,"
637 					    " check man page\n", s);
638 				goto error;
639 			}
640 
641 			*mode |= br->mode;
642 
643 			if (!p)
644 				break;
645 
646 			s = p + 1;
647 		}
648 	}
649 	ret = 0;
650 
651 	/* default to any branch */
652 	if ((*mode & ~ONLY_PLM) == 0) {
653 		*mode = PERF_SAMPLE_BRANCH_ANY;
654 	}
655 error:
656 	free(os);
657 	return ret;
658 }
659 
660 static void callchain_debug(void)
661 {
662 	static const char *str[CALLCHAIN_MAX] = { "NONE", "FP", "DWARF", "LBR" };
663 
664 	pr_debug("callchain: type %s\n", str[callchain_param.record_mode]);
665 
666 	if (callchain_param.record_mode == CALLCHAIN_DWARF)
667 		pr_debug("callchain: stack dump size %d\n",
668 			 callchain_param.dump_size);
669 }
670 
671 int record_parse_callchain_opt(const struct option *opt __maybe_unused,
672 			       const char *arg,
673 			       int unset)
674 {
675 	int ret;
676 
677 	callchain_param.enabled = !unset;
678 
679 	/* --no-call-graph */
680 	if (unset) {
681 		callchain_param.record_mode = CALLCHAIN_NONE;
682 		pr_debug("callchain: disabled\n");
683 		return 0;
684 	}
685 
686 	ret = parse_callchain_record_opt(arg);
687 	if (!ret)
688 		callchain_debug();
689 
690 	return ret;
691 }
692 
693 int record_callchain_opt(const struct option *opt __maybe_unused,
694 			 const char *arg __maybe_unused,
695 			 int unset __maybe_unused)
696 {
697 	callchain_param.enabled = true;
698 
699 	if (callchain_param.record_mode == CALLCHAIN_NONE)
700 		callchain_param.record_mode = CALLCHAIN_FP;
701 
702 	callchain_debug();
703 	return 0;
704 }
705 
706 static int perf_record_config(const char *var, const char *value, void *cb)
707 {
708 	if (!strcmp(var, "record.call-graph"))
709 		var = "call-graph.record-mode"; /* fall-through */
710 
711 	return perf_default_config(var, value, cb);
712 }
713 
714 struct clockid_map {
715 	const char *name;
716 	int clockid;
717 };
718 
719 #define CLOCKID_MAP(n, c)	\
720 	{ .name = n, .clockid = (c), }
721 
722 #define CLOCKID_END	{ .name = NULL, }
723 
724 
725 /*
726  * Add the missing ones, we need to build on many distros...
727  */
728 #ifndef CLOCK_MONOTONIC_RAW
729 #define CLOCK_MONOTONIC_RAW 4
730 #endif
731 #ifndef CLOCK_BOOTTIME
732 #define CLOCK_BOOTTIME 7
733 #endif
734 #ifndef CLOCK_TAI
735 #define CLOCK_TAI 11
736 #endif
737 
738 static const struct clockid_map clockids[] = {
739 	/* available for all events, NMI safe */
740 	CLOCKID_MAP("monotonic", CLOCK_MONOTONIC),
741 	CLOCKID_MAP("monotonic_raw", CLOCK_MONOTONIC_RAW),
742 
743 	/* available for some events */
744 	CLOCKID_MAP("realtime", CLOCK_REALTIME),
745 	CLOCKID_MAP("boottime", CLOCK_BOOTTIME),
746 	CLOCKID_MAP("tai", CLOCK_TAI),
747 
748 	/* available for the lazy */
749 	CLOCKID_MAP("mono", CLOCK_MONOTONIC),
750 	CLOCKID_MAP("raw", CLOCK_MONOTONIC_RAW),
751 	CLOCKID_MAP("real", CLOCK_REALTIME),
752 	CLOCKID_MAP("boot", CLOCK_BOOTTIME),
753 
754 	CLOCKID_END,
755 };
756 
757 static int parse_clockid(const struct option *opt, const char *str, int unset)
758 {
759 	struct record_opts *opts = (struct record_opts *)opt->value;
760 	const struct clockid_map *cm;
761 	const char *ostr = str;
762 
763 	if (unset) {
764 		opts->use_clockid = 0;
765 		return 0;
766 	}
767 
768 	/* no arg passed */
769 	if (!str)
770 		return 0;
771 
772 	/* no setting it twice */
773 	if (opts->use_clockid)
774 		return -1;
775 
776 	opts->use_clockid = true;
777 
778 	/* if its a number, we're done */
779 	if (sscanf(str, "%d", &opts->clockid) == 1)
780 		return 0;
781 
782 	/* allow a "CLOCK_" prefix to the name */
783 	if (!strncasecmp(str, "CLOCK_", 6))
784 		str += 6;
785 
786 	for (cm = clockids; cm->name; cm++) {
787 		if (!strcasecmp(str, cm->name)) {
788 			opts->clockid = cm->clockid;
789 			return 0;
790 		}
791 	}
792 
793 	opts->use_clockid = false;
794 	ui__warning("unknown clockid %s, check man page\n", ostr);
795 	return -1;
796 }
797 
798 static const char * const __record_usage[] = {
799 	"perf record [<options>] [<command>]",
800 	"perf record [<options>] -- <command> [<options>]",
801 	NULL
802 };
803 const char * const *record_usage = __record_usage;
804 
805 /*
806  * XXX Ideally would be local to cmd_record() and passed to a record__new
807  * because we need to have access to it in record__exit, that is called
808  * after cmd_record() exits, but since record_options need to be accessible to
809  * builtin-script, leave it here.
810  *
811  * At least we don't ouch it in all the other functions here directly.
812  *
813  * Just say no to tons of global variables, sigh.
814  */
815 static struct record record = {
816 	.opts = {
817 		.sample_time	     = true,
818 		.mmap_pages	     = UINT_MAX,
819 		.user_freq	     = UINT_MAX,
820 		.user_interval	     = ULLONG_MAX,
821 		.freq		     = 4000,
822 		.target		     = {
823 			.uses_mmap   = true,
824 			.default_per_cpu = true,
825 		},
826 	},
827 	.tool = {
828 		.sample		= process_sample_event,
829 		.fork		= perf_event__process_fork,
830 		.comm		= perf_event__process_comm,
831 		.mmap		= perf_event__process_mmap,
832 		.mmap2		= perf_event__process_mmap2,
833 	},
834 };
835 
836 #define CALLCHAIN_HELP "setup and enables call-graph (stack chain/backtrace) recording: "
837 
838 #ifdef HAVE_DWARF_UNWIND_SUPPORT
839 const char record_callchain_help[] = CALLCHAIN_HELP "fp dwarf lbr";
840 #else
841 const char record_callchain_help[] = CALLCHAIN_HELP "fp lbr";
842 #endif
843 
844 /*
845  * XXX Will stay a global variable till we fix builtin-script.c to stop messing
846  * with it and switch to use the library functions in perf_evlist that came
847  * from builtin-record.c, i.e. use record_opts,
848  * perf_evlist__prepare_workload, etc instead of fork+exec'in 'perf record',
849  * using pipes, etc.
850  */
851 struct option __record_options[] = {
852 	OPT_CALLBACK('e', "event", &record.evlist, "event",
853 		     "event selector. use 'perf list' to list available events",
854 		     parse_events_option),
855 	OPT_CALLBACK(0, "filter", &record.evlist, "filter",
856 		     "event filter", parse_filter),
857 	OPT_STRING('p', "pid", &record.opts.target.pid, "pid",
858 		    "record events on existing process id"),
859 	OPT_STRING('t', "tid", &record.opts.target.tid, "tid",
860 		    "record events on existing thread id"),
861 	OPT_INTEGER('r', "realtime", &record.realtime_prio,
862 		    "collect data with this RT SCHED_FIFO priority"),
863 	OPT_BOOLEAN(0, "no-buffering", &record.opts.no_buffering,
864 		    "collect data without buffering"),
865 	OPT_BOOLEAN('R', "raw-samples", &record.opts.raw_samples,
866 		    "collect raw sample records from all opened counters"),
867 	OPT_BOOLEAN('a', "all-cpus", &record.opts.target.system_wide,
868 			    "system-wide collection from all CPUs"),
869 	OPT_STRING('C', "cpu", &record.opts.target.cpu_list, "cpu",
870 		    "list of cpus to monitor"),
871 	OPT_U64('c', "count", &record.opts.user_interval, "event period to sample"),
872 	OPT_STRING('o', "output", &record.file.path, "file",
873 		    "output file name"),
874 	OPT_BOOLEAN_SET('i', "no-inherit", &record.opts.no_inherit,
875 			&record.opts.no_inherit_set,
876 			"child tasks do not inherit counters"),
877 	OPT_UINTEGER('F', "freq", &record.opts.user_freq, "profile at this frequency"),
878 	OPT_CALLBACK('m', "mmap-pages", &record.opts.mmap_pages, "pages",
879 		     "number of mmap data pages",
880 		     perf_evlist__parse_mmap_pages),
881 	OPT_BOOLEAN(0, "group", &record.opts.group,
882 		    "put the counters into a counter group"),
883 	OPT_CALLBACK_NOOPT('g', NULL, &record.opts,
884 			   NULL, "enables call-graph recording" ,
885 			   &record_callchain_opt),
886 	OPT_CALLBACK(0, "call-graph", &record.opts,
887 		     "mode[,dump_size]", record_callchain_help,
888 		     &record_parse_callchain_opt),
889 	OPT_INCR('v', "verbose", &verbose,
890 		    "be more verbose (show counter open errors, etc)"),
891 	OPT_BOOLEAN('q', "quiet", &quiet, "don't print any message"),
892 	OPT_BOOLEAN('s', "stat", &record.opts.inherit_stat,
893 		    "per thread counts"),
894 	OPT_BOOLEAN('d', "data", &record.opts.sample_address,
895 		    "Sample addresses"),
896 	OPT_BOOLEAN('T', "timestamp", &record.opts.sample_time, "Sample timestamps"),
897 	OPT_BOOLEAN('P', "period", &record.opts.period, "Sample period"),
898 	OPT_BOOLEAN('n', "no-samples", &record.opts.no_samples,
899 		    "don't sample"),
900 	OPT_BOOLEAN('N', "no-buildid-cache", &record.no_buildid_cache,
901 		    "do not update the buildid cache"),
902 	OPT_BOOLEAN('B', "no-buildid", &record.no_buildid,
903 		    "do not collect buildids in perf.data"),
904 	OPT_CALLBACK('G', "cgroup", &record.evlist, "name",
905 		     "monitor event in cgroup name only",
906 		     parse_cgroups),
907 	OPT_UINTEGER('D', "delay", &record.opts.initial_delay,
908 		  "ms to wait before starting measurement after program start"),
909 	OPT_STRING('u', "uid", &record.opts.target.uid_str, "user",
910 		   "user to profile"),
911 
912 	OPT_CALLBACK_NOOPT('b', "branch-any", &record.opts.branch_stack,
913 		     "branch any", "sample any taken branches",
914 		     parse_branch_stack),
915 
916 	OPT_CALLBACK('j', "branch-filter", &record.opts.branch_stack,
917 		     "branch filter mask", "branch stack filter modes",
918 		     parse_branch_stack),
919 	OPT_BOOLEAN('W', "weight", &record.opts.sample_weight,
920 		    "sample by weight (on special events only)"),
921 	OPT_BOOLEAN(0, "transaction", &record.opts.sample_transaction,
922 		    "sample transaction flags (special events only)"),
923 	OPT_BOOLEAN(0, "per-thread", &record.opts.target.per_thread,
924 		    "use per-thread mmaps"),
925 	OPT_BOOLEAN('I', "intr-regs", &record.opts.sample_intr_regs,
926 		    "Sample machine registers on interrupt"),
927 	OPT_BOOLEAN(0, "running-time", &record.opts.running_time,
928 		    "Record running/enabled time of read (:S) events"),
929 	OPT_CALLBACK('k', "clockid", &record.opts,
930 	"clockid", "clockid to use for events, see clock_gettime()",
931 	parse_clockid),
932 	OPT_END()
933 };
934 
935 struct option *record_options = __record_options;
936 
937 int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
938 {
939 	int err = -ENOMEM;
940 	struct record *rec = &record;
941 	char errbuf[BUFSIZ];
942 
943 	rec->evlist = perf_evlist__new();
944 	if (rec->evlist == NULL)
945 		return -ENOMEM;
946 
947 	perf_config(perf_record_config, rec);
948 
949 	argc = parse_options(argc, argv, record_options, record_usage,
950 			    PARSE_OPT_STOP_AT_NON_OPTION);
951 	if (!argc && target__none(&rec->opts.target))
952 		usage_with_options(record_usage, record_options);
953 
954 	if (nr_cgroups && !rec->opts.target.system_wide) {
955 		ui__error("cgroup monitoring only available in"
956 			  " system-wide mode\n");
957 		usage_with_options(record_usage, record_options);
958 	}
959 
960 	symbol__init(NULL);
961 
962 	if (symbol_conf.kptr_restrict)
963 		pr_warning(
964 "WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted,\n"
965 "check /proc/sys/kernel/kptr_restrict.\n\n"
966 "Samples in kernel functions may not be resolved if a suitable vmlinux\n"
967 "file is not found in the buildid cache or in the vmlinux path.\n\n"
968 "Samples in kernel modules won't be resolved at all.\n\n"
969 "If some relocation was applied (e.g. kexec) symbols may be misresolved\n"
970 "even with a suitable vmlinux or kallsyms file.\n\n");
971 
972 	if (rec->no_buildid_cache || rec->no_buildid)
973 		disable_buildid_cache();
974 
975 	if (rec->evlist->nr_entries == 0 &&
976 	    perf_evlist__add_default(rec->evlist) < 0) {
977 		pr_err("Not enough memory for event selector list\n");
978 		goto out_symbol_exit;
979 	}
980 
981 	if (rec->opts.target.tid && !rec->opts.no_inherit_set)
982 		rec->opts.no_inherit = true;
983 
984 	err = target__validate(&rec->opts.target);
985 	if (err) {
986 		target__strerror(&rec->opts.target, err, errbuf, BUFSIZ);
987 		ui__warning("%s", errbuf);
988 	}
989 
990 	err = target__parse_uid(&rec->opts.target);
991 	if (err) {
992 		int saved_errno = errno;
993 
994 		target__strerror(&rec->opts.target, err, errbuf, BUFSIZ);
995 		ui__error("%s", errbuf);
996 
997 		err = -saved_errno;
998 		goto out_symbol_exit;
999 	}
1000 
1001 	err = -ENOMEM;
1002 	if (perf_evlist__create_maps(rec->evlist, &rec->opts.target) < 0)
1003 		usage_with_options(record_usage, record_options);
1004 
1005 	if (record_opts__config(&rec->opts)) {
1006 		err = -EINVAL;
1007 		goto out_symbol_exit;
1008 	}
1009 
1010 	err = __cmd_record(&record, argc, argv);
1011 out_symbol_exit:
1012 	perf_evlist__delete(rec->evlist);
1013 	symbol__exit();
1014 	return err;
1015 }
1016