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7
8#include "builtin.h"
9
10#include "perf.h"
11
12#include "util/util.h"
13#include "util/parse-options.h"
14#include "util/parse-events.h"
15#include "util/string.h"
16
17#include "util/header.h"
18#include "util/event.h"
19#include "util/debug.h"
20#include "util/trace-event.h"
21
22#include <unistd.h>
23#include <sched.h>
24
25#define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1)
26#define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask))
27
28static int fd[MAX_NR_CPUS][MAX_COUNTERS];
29
30static long default_interval = 100000;
31
32static int nr_cpus = 0;
33static unsigned int page_size;
34static unsigned int mmap_pages = 128;
35static int freq = 0;
36static int output;
37static const char *output_name = "perf.data";
38static int group = 0;
39static unsigned int realtime_prio = 0;
40static int raw_samples = 0;
41static int system_wide = 0;
42static int profile_cpu = -1;
43static pid_t target_pid = -1;
44static pid_t child_pid = -1;
45static int inherit = 1;
46static int force = 0;
47static int append_file = 0;
48static int call_graph = 0;
49static int inherit_stat = 0;
50static int no_samples = 0;
51static int sample_address = 0;
52static int multiplex = 0;
53static int multiplex_fd = -1;
54
55static long samples;
56static struct timeval last_read;
57static struct timeval this_read;
58
59static u64 bytes_written;
60
61static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
62
63static int nr_poll;
64static int nr_cpu;
65
66static int file_new = 1;
67
68struct perf_header *header;
69
70struct mmap_data {
71 int counter;
72 void *base;
73 unsigned int mask;
74 unsigned int prev;
75};
76
77static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
78
79static unsigned long mmap_read_head(struct mmap_data *md)
80{
81 struct perf_event_mmap_page *pc = md->base;
82 long head;
83
84 head = pc->data_head;
85 rmb();
86
87 return head;
88}
89
90static void mmap_write_tail(struct mmap_data *md, unsigned long tail)
91{
92 struct perf_event_mmap_page *pc = md->base;
93
94
95
96
97
98 pc->data_tail = tail;
99}
100
101static void write_output(void *buf, size_t size)
102{
103 while (size) {
104 int ret = write(output, buf, size);
105
106 if (ret < 0)
107 die("failed to write");
108
109 size -= ret;
110 buf += ret;
111
112 bytes_written += ret;
113 }
114}
115
116static void mmap_read(struct mmap_data *md)
117{
118 unsigned int head = mmap_read_head(md);
119 unsigned int old = md->prev;
120 unsigned char *data = md->base + page_size;
121 unsigned long size;
122 void *buf;
123 int diff;
124
125 gettimeofday(&this_read, NULL);
126
127
128
129
130
131
132
133
134
135 diff = head - old;
136 if (diff < 0) {
137 struct timeval iv;
138 unsigned long msecs;
139
140 timersub(&this_read, &last_read, &iv);
141 msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
142
143 fprintf(stderr, "WARNING: failed to keep up with mmap data."
144 " Last read %lu msecs ago.\n", msecs);
145
146
147
148
149 old = head;
150 }
151
152 last_read = this_read;
153
154 if (old != head)
155 samples++;
156
157 size = head - old;
158
159 if ((old & md->mask) + size != (head & md->mask)) {
160 buf = &data[old & md->mask];
161 size = md->mask + 1 - (old & md->mask);
162 old += size;
163
164 write_output(buf, size);
165 }
166
167 buf = &data[old & md->mask];
168 size = head - old;
169 old += size;
170
171 write_output(buf, size);
172
173 md->prev = old;
174 mmap_write_tail(md, old);
175}
176
177static volatile int done = 0;
178static volatile int signr = -1;
179
180static void sig_handler(int sig)
181{
182 done = 1;
183 signr = sig;
184}
185
186static void sig_atexit(void)
187{
188 if (child_pid != -1)
189 kill(child_pid, SIGTERM);
190
191 if (signr == -1)
192 return;
193
194 signal(signr, SIG_DFL);
195 kill(getpid(), signr);
196}
197
198static pid_t pid_synthesize_comm_event(pid_t pid, int full)
199{
200 struct comm_event comm_ev;
201 char filename[PATH_MAX];
202 char bf[BUFSIZ];
203 FILE *fp;
204 size_t size = 0;
205 DIR *tasks;
206 struct dirent dirent, *next;
207 pid_t tgid = 0;
208
209 snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
210
211 fp = fopen(filename, "r");
212 if (fp == NULL) {
213
214
215
216 if (verbose)
217 fprintf(stderr, "couldn't open %s\n", filename);
218 return 0;
219 }
220
221 memset(&comm_ev, 0, sizeof(comm_ev));
222 while (!comm_ev.comm[0] || !comm_ev.pid) {
223 if (fgets(bf, sizeof(bf), fp) == NULL)
224 goto out_failure;
225
226 if (memcmp(bf, "Name:", 5) == 0) {
227 char *name = bf + 5;
228 while (*name && isspace(*name))
229 ++name;
230 size = strlen(name) - 1;
231 memcpy(comm_ev.comm, name, size++);
232 } else if (memcmp(bf, "Tgid:", 5) == 0) {
233 char *tgids = bf + 5;
234 while (*tgids && isspace(*tgids))
235 ++tgids;
236 tgid = comm_ev.pid = atoi(tgids);
237 }
238 }
239
240 comm_ev.header.type = PERF_RECORD_COMM;
241 size = ALIGN(size, sizeof(u64));
242 comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
243
244 if (!full) {
245 comm_ev.tid = pid;
246
247 write_output(&comm_ev, comm_ev.header.size);
248 goto out_fclose;
249 }
250
251 snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
252
253 tasks = opendir(filename);
254 while (!readdir_r(tasks, &dirent, &next) && next) {
255 char *end;
256 pid = strtol(dirent.d_name, &end, 10);
257 if (*end)
258 continue;
259
260 comm_ev.tid = pid;
261
262 write_output(&comm_ev, comm_ev.header.size);
263 }
264 closedir(tasks);
265
266out_fclose:
267 fclose(fp);
268 return tgid;
269
270out_failure:
271 fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
272 filename);
273 exit(EXIT_FAILURE);
274}
275
276static void pid_synthesize_mmap_samples(pid_t pid, pid_t tgid)
277{
278 char filename[PATH_MAX];
279 FILE *fp;
280
281 snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);
282
283 fp = fopen(filename, "r");
284 if (fp == NULL) {
285
286
287
288 if (verbose)
289 fprintf(stderr, "couldn't open %s\n", filename);
290 return;
291 }
292 while (1) {
293 char bf[BUFSIZ], *pbf = bf;
294 struct mmap_event mmap_ev = {
295 .header = { .type = PERF_RECORD_MMAP },
296 };
297 int n;
298 size_t size;
299 if (fgets(bf, sizeof(bf), fp) == NULL)
300 break;
301
302
303 n = hex2u64(pbf, &mmap_ev.start);
304 if (n < 0)
305 continue;
306 pbf += n + 1;
307 n = hex2u64(pbf, &mmap_ev.len);
308 if (n < 0)
309 continue;
310 pbf += n + 3;
311 if (*pbf == 'x') {
312 char *execname = strchr(bf, '/');
313
314
315 if (execname == NULL)
316 execname = strstr(bf, "[vdso]");
317
318 if (execname == NULL)
319 continue;
320
321 size = strlen(execname);
322 execname[size - 1] = '\0';
323 memcpy(mmap_ev.filename, execname, size);
324 size = ALIGN(size, sizeof(u64));
325 mmap_ev.len -= mmap_ev.start;
326 mmap_ev.header.size = (sizeof(mmap_ev) -
327 (sizeof(mmap_ev.filename) - size));
328 mmap_ev.pid = tgid;
329 mmap_ev.tid = pid;
330
331 write_output(&mmap_ev, mmap_ev.header.size);
332 }
333 }
334
335 fclose(fp);
336}
337
338static void synthesize_all(void)
339{
340 DIR *proc;
341 struct dirent dirent, *next;
342
343 proc = opendir("/proc");
344
345 while (!readdir_r(proc, &dirent, &next) && next) {
346 char *end;
347 pid_t pid, tgid;
348
349 pid = strtol(dirent.d_name, &end, 10);
350 if (*end)
351 continue;
352
353 tgid = pid_synthesize_comm_event(pid, 1);
354 pid_synthesize_mmap_samples(pid, tgid);
355 }
356
357 closedir(proc);
358}
359
360static int group_fd;
361
362static struct perf_header_attr *get_header_attr(struct perf_event_attr *a, int nr)
363{
364 struct perf_header_attr *h_attr;
365
366 if (nr < header->attrs) {
367 h_attr = header->attr[nr];
368 } else {
369 h_attr = perf_header_attr__new(a);
370 perf_header__add_attr(header, h_attr);
371 }
372
373 return h_attr;
374}
375
376static void create_counter(int counter, int cpu, pid_t pid)
377{
378 struct perf_event_attr *attr = attrs + counter;
379 struct perf_header_attr *h_attr;
380 int track = !counter;
381 struct {
382 u64 count;
383 u64 time_enabled;
384 u64 time_running;
385 u64 id;
386 } read_data;
387
388 attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
389 PERF_FORMAT_TOTAL_TIME_RUNNING |
390 PERF_FORMAT_ID;
391
392 attr->sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
393
394 if (freq) {
395 attr->sample_type |= PERF_SAMPLE_PERIOD;
396 attr->freq = 1;
397 attr->sample_freq = freq;
398 }
399
400 if (no_samples)
401 attr->sample_freq = 0;
402
403 if (inherit_stat)
404 attr->inherit_stat = 1;
405
406 if (sample_address)
407 attr->sample_type |= PERF_SAMPLE_ADDR;
408
409 if (call_graph)
410 attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
411
412 if (raw_samples) {
413 attr->sample_type |= PERF_SAMPLE_TIME;
414 attr->sample_type |= PERF_SAMPLE_RAW;
415 attr->sample_type |= PERF_SAMPLE_CPU;
416 }
417
418 attr->mmap = track;
419 attr->comm = track;
420 attr->inherit = (cpu < 0) && inherit;
421 attr->disabled = 1;
422
423try_again:
424 fd[nr_cpu][counter] = sys_perf_event_open(attr, pid, cpu, group_fd, 0);
425
426 if (fd[nr_cpu][counter] < 0) {
427 int err = errno;
428
429 if (err == EPERM || err == EACCES)
430 die("Permission error - are you root?\n");
431 else if (err == ENODEV && profile_cpu != -1)
432 die("No such device - did you specify an out-of-range profile CPU?\n");
433
434
435
436
437
438
439 if (attr->type == PERF_TYPE_HARDWARE
440 && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
441
442 if (verbose)
443 warning(" ... trying to fall back to cpu-clock-ticks\n");
444 attr->type = PERF_TYPE_SOFTWARE;
445 attr->config = PERF_COUNT_SW_CPU_CLOCK;
446 goto try_again;
447 }
448 printf("\n");
449 error("perfcounter syscall returned with %d (%s)\n",
450 fd[nr_cpu][counter], strerror(err));
451 die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
452 exit(-1);
453 }
454
455 h_attr = get_header_attr(attr, counter);
456
457 if (!file_new) {
458 if (memcmp(&h_attr->attr, attr, sizeof(*attr))) {
459 fprintf(stderr, "incompatible append\n");
460 exit(-1);
461 }
462 }
463
464 if (read(fd[nr_cpu][counter], &read_data, sizeof(read_data)) == -1) {
465 perror("Unable to read perf file descriptor\n");
466 exit(-1);
467 }
468
469 perf_header_attr__add_id(h_attr, read_data.id);
470
471 assert(fd[nr_cpu][counter] >= 0);
472 fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
473
474
475
476
477 if (group && group_fd == -1)
478 group_fd = fd[nr_cpu][counter];
479 if (multiplex && multiplex_fd == -1)
480 multiplex_fd = fd[nr_cpu][counter];
481
482 if (multiplex && fd[nr_cpu][counter] != multiplex_fd) {
483 int ret;
484
485 ret = ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_SET_OUTPUT, multiplex_fd);
486 assert(ret != -1);
487 } else {
488 event_array[nr_poll].fd = fd[nr_cpu][counter];
489 event_array[nr_poll].events = POLLIN;
490 nr_poll++;
491
492 mmap_array[nr_cpu][counter].counter = counter;
493 mmap_array[nr_cpu][counter].prev = 0;
494 mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
495 mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
496 PROT_READ|PROT_WRITE, MAP_SHARED, fd[nr_cpu][counter], 0);
497 if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
498 error("failed to mmap with %d (%s)\n", errno, strerror(errno));
499 exit(-1);
500 }
501 }
502
503 ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_ENABLE);
504}
505
506static void open_counters(int cpu, pid_t pid)
507{
508 int counter;
509
510 group_fd = -1;
511 for (counter = 0; counter < nr_counters; counter++)
512 create_counter(counter, cpu, pid);
513
514 nr_cpu++;
515}
516
517static void atexit_header(void)
518{
519 header->data_size += bytes_written;
520
521 perf_header__write(header, output);
522}
523
524static int __cmd_record(int argc, const char **argv)
525{
526 int i, counter;
527 struct stat st;
528 pid_t pid = 0;
529 int flags;
530 int ret;
531 unsigned long waking = 0;
532
533 page_size = sysconf(_SC_PAGE_SIZE);
534 nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
535 assert(nr_cpus <= MAX_NR_CPUS);
536 assert(nr_cpus >= 0);
537
538 atexit(sig_atexit);
539 signal(SIGCHLD, sig_handler);
540 signal(SIGINT, sig_handler);
541
542 if (!stat(output_name, &st) && st.st_size) {
543 if (!force && !append_file) {
544 fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
545 output_name);
546 exit(-1);
547 }
548 } else {
549 append_file = 0;
550 }
551
552 flags = O_CREAT|O_RDWR;
553 if (append_file)
554 file_new = 0;
555 else
556 flags |= O_TRUNC;
557
558 output = open(output_name, flags, S_IRUSR|S_IWUSR);
559 if (output < 0) {
560 perror("failed to create output file");
561 exit(-1);
562 }
563
564 if (!file_new)
565 header = perf_header__read(output);
566 else
567 header = perf_header__new();
568
569
570 if (raw_samples) {
571 read_tracing_data(attrs, nr_counters);
572 } else {
573 for (i = 0; i < nr_counters; i++) {
574 if (attrs[i].sample_type & PERF_SAMPLE_RAW) {
575 read_tracing_data(attrs, nr_counters);
576 break;
577 }
578 }
579 }
580 atexit(atexit_header);
581
582 if (!system_wide) {
583 pid = target_pid;
584 if (pid == -1)
585 pid = getpid();
586
587 open_counters(profile_cpu, pid);
588 } else {
589 if (profile_cpu != -1) {
590 open_counters(profile_cpu, target_pid);
591 } else {
592 for (i = 0; i < nr_cpus; i++)
593 open_counters(i, target_pid);
594 }
595 }
596
597 if (file_new)
598 perf_header__write(header, output);
599
600 if (!system_wide) {
601 pid_t tgid = pid_synthesize_comm_event(pid, 0);
602 pid_synthesize_mmap_samples(pid, tgid);
603 } else
604 synthesize_all();
605
606 if (target_pid == -1 && argc) {
607 pid = fork();
608 if (pid < 0)
609 perror("failed to fork");
610
611 if (!pid) {
612 if (execvp(argv[0], (char **)argv)) {
613 perror(argv[0]);
614 exit(-1);
615 }
616 }
617
618 child_pid = pid;
619 }
620
621 if (realtime_prio) {
622 struct sched_param param;
623
624 param.sched_priority = realtime_prio;
625 if (sched_setscheduler(0, SCHED_FIFO, ¶m)) {
626 printf("Could not set realtime priority.\n");
627 exit(-1);
628 }
629 }
630
631 for (;;) {
632 int hits = samples;
633
634 for (i = 0; i < nr_cpu; i++) {
635 for (counter = 0; counter < nr_counters; counter++) {
636 if (mmap_array[i][counter].base)
637 mmap_read(&mmap_array[i][counter]);
638 }
639 }
640
641 if (hits == samples) {
642 if (done)
643 break;
644 ret = poll(event_array, nr_poll, -1);
645 waking++;
646 }
647
648 if (done) {
649 for (i = 0; i < nr_cpu; i++) {
650 for (counter = 0; counter < nr_counters; counter++)
651 ioctl(fd[i][counter], PERF_EVENT_IOC_DISABLE);
652 }
653 }
654 }
655
656 fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
657
658
659
660
661 fprintf(stderr,
662 "[ perf record: Captured and wrote %.3f MB %s (~%lld samples) ]\n",
663 (double)bytes_written / 1024.0 / 1024.0,
664 output_name,
665 bytes_written / 24);
666
667 return 0;
668}
669
670static const char * const record_usage[] = {
671 "perf record [<options>] [<command>]",
672 "perf record [<options>] -- <command> [<options>]",
673 NULL
674};
675
676static const struct option options[] = {
677 OPT_CALLBACK('e', "event", NULL, "event",
678 "event selector. use 'perf list' to list available events",
679 parse_events),
680 OPT_INTEGER('p', "pid", &target_pid,
681 "record events on existing pid"),
682 OPT_INTEGER('r', "realtime", &realtime_prio,
683 "collect data with this RT SCHED_FIFO priority"),
684 OPT_BOOLEAN('R', "raw-samples", &raw_samples,
685 "collect raw sample records from all opened counters"),
686 OPT_BOOLEAN('a', "all-cpus", &system_wide,
687 "system-wide collection from all CPUs"),
688 OPT_BOOLEAN('A', "append", &append_file,
689 "append to the output file to do incremental profiling"),
690 OPT_INTEGER('C', "profile_cpu", &profile_cpu,
691 "CPU to profile on"),
692 OPT_BOOLEAN('f', "force", &force,
693 "overwrite existing data file"),
694 OPT_LONG('c', "count", &default_interval,
695 "event period to sample"),
696 OPT_STRING('o', "output", &output_name, "file",
697 "output file name"),
698 OPT_BOOLEAN('i', "inherit", &inherit,
699 "child tasks inherit counters"),
700 OPT_INTEGER('F', "freq", &freq,
701 "profile at this frequency"),
702 OPT_INTEGER('m', "mmap-pages", &mmap_pages,
703 "number of mmap data pages"),
704 OPT_BOOLEAN('g', "call-graph", &call_graph,
705 "do call-graph (stack chain/backtrace) recording"),
706 OPT_BOOLEAN('v', "verbose", &verbose,
707 "be more verbose (show counter open errors, etc)"),
708 OPT_BOOLEAN('s', "stat", &inherit_stat,
709 "per thread counts"),
710 OPT_BOOLEAN('d', "data", &sample_address,
711 "Sample addresses"),
712 OPT_BOOLEAN('n', "no-samples", &no_samples,
713 "don't sample"),
714 OPT_BOOLEAN('M', "multiplex", &multiplex,
715 "multiplex counter output in a single channel"),
716 OPT_END()
717};
718
719int cmd_record(int argc, const char **argv, const char *prefix __used)
720{
721 int counter;
722
723 argc = parse_options(argc, argv, options, record_usage,
724 PARSE_OPT_STOP_AT_NON_OPTION);
725 if (!argc && target_pid == -1 && !system_wide)
726 usage_with_options(record_usage, options);
727
728 if (!nr_counters) {
729 nr_counters = 1;
730 attrs[0].type = PERF_TYPE_HARDWARE;
731 attrs[0].config = PERF_COUNT_HW_CPU_CYCLES;
732 }
733
734 for (counter = 0; counter < nr_counters; counter++) {
735 if (attrs[counter].sample_period)
736 continue;
737
738 attrs[counter].sample_period = default_interval;
739 }
740
741 return __cmd_record(argc, argv);
742}
743
