Commit | Line | Data |
---|---|---|
abaff32a IM |
1 | /* |
2 | * perf record: Record the profile of a workload (or a CPU, or a PID) into | |
3 | * the perf.data output file - for later analysis via perf report. | |
4 | */ | |
1a482f38 | 5 | #include "perf.h" |
16f762a2 | 6 | #include "builtin.h" |
6eda5838 | 7 | #include "util/util.h" |
0e9b20b8 | 8 | #include "util/parse-options.h" |
8ad8db37 | 9 | #include "util/parse-events.h" |
a0055ae2 | 10 | #include "util/string.h" |
6eda5838 | 11 | |
97124d5e | 12 | #include <unistd.h> |
de9ac07b | 13 | #include <sched.h> |
de9ac07b | 14 | |
0e9b20b8 IM |
15 | #define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1) |
16 | #define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask)) | |
1a853e36 | 17 | |
de9ac07b PZ |
18 | static int default_interval = 100000; |
19 | static int event_count[MAX_COUNTERS]; | |
8ad8db37 | 20 | |
de9ac07b | 21 | static int fd[MAX_NR_CPUS][MAX_COUNTERS]; |
3cf165fc | 22 | static int nr_cpus = 0; |
de9ac07b | 23 | static unsigned int page_size; |
3cf165fc | 24 | static unsigned int mmap_pages = 128; |
de9ac07b | 25 | static int output; |
23ac9cbe | 26 | static const char *output_name = "perf.data"; |
de9ac07b | 27 | static int group = 0; |
16c8a109 PZ |
28 | static unsigned int realtime_prio = 0; |
29 | static int system_wide = 0; | |
1a853e36 | 30 | static pid_t target_pid = -1; |
16c8a109 | 31 | static int inherit = 1; |
97124d5e | 32 | static int force = 0; |
abaff32a | 33 | static int append_file = 0; |
de9ac07b PZ |
34 | |
35 | const unsigned int default_count[] = { | |
36 | 1000000, | |
37 | 1000000, | |
38 | 10000, | |
39 | 10000, | |
40 | 1000000, | |
41 | 10000, | |
42 | }; | |
43 | ||
de9ac07b PZ |
44 | struct mmap_data { |
45 | int counter; | |
46 | void *base; | |
47 | unsigned int mask; | |
48 | unsigned int prev; | |
49 | }; | |
50 | ||
51 | static unsigned int mmap_read_head(struct mmap_data *md) | |
52 | { | |
53 | struct perf_counter_mmap_page *pc = md->base; | |
54 | int head; | |
55 | ||
56 | head = pc->data_head; | |
57 | rmb(); | |
58 | ||
59 | return head; | |
60 | } | |
61 | ||
62 | static long events; | |
63 | static struct timeval last_read, this_read; | |
64 | ||
65 | static void mmap_read(struct mmap_data *md) | |
66 | { | |
67 | unsigned int head = mmap_read_head(md); | |
68 | unsigned int old = md->prev; | |
69 | unsigned char *data = md->base + page_size; | |
70 | unsigned long size; | |
71 | void *buf; | |
72 | int diff; | |
73 | ||
74 | gettimeofday(&this_read, NULL); | |
75 | ||
76 | /* | |
77 | * If we're further behind than half the buffer, there's a chance | |
78 | * the writer will bite our tail and screw up the events under us. | |
79 | * | |
80 | * If we somehow ended up ahead of the head, we got messed up. | |
81 | * | |
82 | * In either case, truncate and restart at head. | |
83 | */ | |
84 | diff = head - old; | |
85 | if (diff > md->mask / 2 || diff < 0) { | |
86 | struct timeval iv; | |
87 | unsigned long msecs; | |
88 | ||
89 | timersub(&this_read, &last_read, &iv); | |
90 | msecs = iv.tv_sec*1000 + iv.tv_usec/1000; | |
91 | ||
92 | fprintf(stderr, "WARNING: failed to keep up with mmap data." | |
93 | " Last read %lu msecs ago.\n", msecs); | |
94 | ||
95 | /* | |
96 | * head points to a known good entry, start there. | |
97 | */ | |
98 | old = head; | |
99 | } | |
100 | ||
101 | last_read = this_read; | |
102 | ||
103 | if (old != head) | |
104 | events++; | |
105 | ||
106 | size = head - old; | |
107 | ||
108 | if ((old & md->mask) + size != (head & md->mask)) { | |
109 | buf = &data[old & md->mask]; | |
110 | size = md->mask + 1 - (old & md->mask); | |
111 | old += size; | |
112 | while (size) { | |
113 | int ret = write(output, buf, size); | |
114 | if (ret < 0) { | |
115 | perror("failed to write"); | |
116 | exit(-1); | |
117 | } | |
118 | size -= ret; | |
119 | buf += ret; | |
120 | } | |
121 | } | |
122 | ||
123 | buf = &data[old & md->mask]; | |
124 | size = head - old; | |
125 | old += size; | |
126 | while (size) { | |
127 | int ret = write(output, buf, size); | |
128 | if (ret < 0) { | |
129 | perror("failed to write"); | |
130 | exit(-1); | |
131 | } | |
132 | size -= ret; | |
133 | buf += ret; | |
134 | } | |
135 | ||
136 | md->prev = old; | |
137 | } | |
138 | ||
139 | static volatile int done = 0; | |
140 | ||
16c8a109 | 141 | static void sig_handler(int sig) |
de9ac07b | 142 | { |
16c8a109 | 143 | done = 1; |
de9ac07b PZ |
144 | } |
145 | ||
16c8a109 PZ |
146 | static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS]; |
147 | static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS]; | |
148 | ||
149 | static int nr_poll; | |
150 | static int nr_cpu; | |
151 | ||
1a853e36 | 152 | struct mmap_event { |
16f762a2 IM |
153 | struct perf_event_header header; |
154 | __u32 pid; | |
155 | __u32 tid; | |
156 | __u64 start; | |
157 | __u64 len; | |
158 | __u64 pgoff; | |
159 | char filename[PATH_MAX]; | |
1a853e36 | 160 | }; |
16f762a2 | 161 | |
1a853e36 | 162 | struct comm_event { |
16f762a2 IM |
163 | struct perf_event_header header; |
164 | __u32 pid; | |
165 | __u32 tid; | |
166 | char comm[16]; | |
1a853e36 ACM |
167 | }; |
168 | ||
f70e87d7 | 169 | static void pid_synthesize_comm_event(pid_t pid, int full) |
1a853e36 | 170 | { |
16f762a2 | 171 | struct comm_event comm_ev; |
1a853e36 ACM |
172 | char filename[PATH_MAX]; |
173 | char bf[BUFSIZ]; | |
a0055ae2 | 174 | int fd, ret; |
1a853e36 | 175 | size_t size; |
a0055ae2 | 176 | char *field, *sep; |
f70e87d7 PZ |
177 | DIR *tasks; |
178 | struct dirent dirent, *next; | |
1a853e36 ACM |
179 | |
180 | snprintf(filename, sizeof(filename), "/proc/%d/stat", pid); | |
181 | ||
182 | fd = open(filename, O_RDONLY); | |
183 | if (fd < 0) { | |
184 | fprintf(stderr, "couldn't open %s\n", filename); | |
185 | exit(EXIT_FAILURE); | |
186 | } | |
187 | if (read(fd, bf, sizeof(bf)) < 0) { | |
188 | fprintf(stderr, "couldn't read %s\n", filename); | |
189 | exit(EXIT_FAILURE); | |
190 | } | |
191 | close(fd); | |
192 | ||
a0055ae2 | 193 | /* 9027 (cat) R 6747 9027 6747 34816 9027 ... */ |
1a853e36 | 194 | memset(&comm_ev, 0, sizeof(comm_ev)); |
a0055ae2 ACM |
195 | field = strchr(bf, '('); |
196 | if (field == NULL) | |
197 | goto out_failure; | |
198 | sep = strchr(++field, ')'); | |
199 | if (sep == NULL) | |
200 | goto out_failure; | |
201 | size = sep - field; | |
202 | memcpy(comm_ev.comm, field, size++); | |
f70e87d7 PZ |
203 | |
204 | comm_ev.pid = pid; | |
1a853e36 | 205 | comm_ev.header.type = PERF_EVENT_COMM; |
1a853e36 ACM |
206 | size = ALIGN(size, sizeof(uint64_t)); |
207 | comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size); | |
16f762a2 | 208 | |
f70e87d7 PZ |
209 | if (!full) { |
210 | comm_ev.tid = pid; | |
211 | ||
212 | ret = write(output, &comm_ev, comm_ev.header.size); | |
213 | if (ret < 0) { | |
214 | perror("failed to write"); | |
215 | exit(-1); | |
216 | } | |
217 | return; | |
218 | } | |
219 | ||
220 | snprintf(filename, sizeof(filename), "/proc/%d/task", pid); | |
221 | ||
222 | tasks = opendir(filename); | |
223 | while (!readdir_r(tasks, &dirent, &next) && next) { | |
224 | char *end; | |
225 | pid = strtol(dirent.d_name, &end, 10); | |
226 | if (*end) | |
227 | continue; | |
228 | ||
229 | comm_ev.tid = pid; | |
230 | ||
231 | ret = write(output, &comm_ev, comm_ev.header.size); | |
232 | if (ret < 0) { | |
233 | perror("failed to write"); | |
234 | exit(-1); | |
235 | } | |
1a853e36 | 236 | } |
f70e87d7 PZ |
237 | closedir(tasks); |
238 | return; | |
239 | ||
a0055ae2 ACM |
240 | out_failure: |
241 | fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n", | |
242 | filename); | |
243 | exit(EXIT_FAILURE); | |
1a853e36 ACM |
244 | } |
245 | ||
f70e87d7 | 246 | static void pid_synthesize_mmap_events(pid_t pid) |
1a853e36 ACM |
247 | { |
248 | char filename[PATH_MAX]; | |
249 | FILE *fp; | |
250 | ||
251 | snprintf(filename, sizeof(filename), "/proc/%d/maps", pid); | |
252 | ||
253 | fp = fopen(filename, "r"); | |
254 | if (fp == NULL) { | |
255 | fprintf(stderr, "couldn't open %s\n", filename); | |
256 | exit(EXIT_FAILURE); | |
257 | } | |
258 | while (1) { | |
a0055ae2 | 259 | char bf[BUFSIZ], *pbf = bf; |
1a853e36 ACM |
260 | struct mmap_event mmap_ev = { |
261 | .header.type = PERF_EVENT_MMAP, | |
262 | }; | |
a0055ae2 | 263 | int n; |
1a853e36 ACM |
264 | size_t size; |
265 | if (fgets(bf, sizeof(bf), fp) == NULL) | |
266 | break; | |
267 | ||
268 | /* 00400000-0040c000 r-xp 00000000 fd:01 41038 /bin/cat */ | |
a0055ae2 ACM |
269 | n = hex2u64(pbf, &mmap_ev.start); |
270 | if (n < 0) | |
271 | continue; | |
272 | pbf += n + 1; | |
273 | n = hex2u64(pbf, &mmap_ev.len); | |
274 | if (n < 0) | |
275 | continue; | |
276 | pbf += n + 3; | |
277 | if (*pbf == 'x') { /* vm_exec */ | |
1a853e36 ACM |
278 | char *execname = strrchr(bf, ' '); |
279 | ||
280 | if (execname == NULL || execname[1] != '/') | |
281 | continue; | |
282 | ||
283 | execname += 1; | |
284 | size = strlen(execname); | |
285 | execname[size - 1] = '\0'; /* Remove \n */ | |
286 | memcpy(mmap_ev.filename, execname, size); | |
287 | size = ALIGN(size, sizeof(uint64_t)); | |
288 | mmap_ev.len -= mmap_ev.start; | |
289 | mmap_ev.header.size = (sizeof(mmap_ev) - | |
290 | (sizeof(mmap_ev.filename) - size)); | |
f70e87d7 | 291 | mmap_ev.pid = pid; |
1a853e36 ACM |
292 | mmap_ev.tid = pid; |
293 | ||
294 | if (write(output, &mmap_ev, mmap_ev.header.size) < 0) { | |
295 | perror("failed to write"); | |
296 | exit(-1); | |
297 | } | |
298 | } | |
299 | } | |
300 | ||
301 | fclose(fp); | |
302 | } | |
303 | ||
f70e87d7 PZ |
304 | static void synthesize_events(void) |
305 | { | |
306 | DIR *proc; | |
307 | struct dirent dirent, *next; | |
308 | ||
309 | proc = opendir("/proc"); | |
310 | ||
311 | while (!readdir_r(proc, &dirent, &next) && next) { | |
312 | char *end; | |
313 | pid_t pid; | |
314 | ||
315 | pid = strtol(dirent.d_name, &end, 10); | |
316 | if (*end) /* only interested in proper numerical dirents */ | |
317 | continue; | |
318 | ||
319 | pid_synthesize_comm_event(pid, 1); | |
320 | pid_synthesize_mmap_events(pid); | |
321 | } | |
322 | ||
323 | closedir(proc); | |
324 | } | |
325 | ||
1a853e36 | 326 | static void open_counters(int cpu, pid_t pid) |
de9ac07b | 327 | { |
c70975bc | 328 | struct perf_counter_attr attr; |
16c8a109 PZ |
329 | int counter, group_fd; |
330 | int track = 1; | |
16c8a109 | 331 | |
1a853e36 | 332 | if (pid > 0) { |
f70e87d7 PZ |
333 | pid_synthesize_comm_event(pid, 0); |
334 | pid_synthesize_mmap_events(pid); | |
1a853e36 | 335 | } |
16c8a109 PZ |
336 | |
337 | group_fd = -1; | |
338 | for (counter = 0; counter < nr_counters; counter++) { | |
339 | ||
c70975bc PZ |
340 | memset(&attr, 0, sizeof(attr)); |
341 | attr.config = event_id[counter]; | |
342 | attr.sample_period = event_count[counter]; | |
343 | attr.sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID; | |
344 | attr.mmap = track; | |
345 | attr.comm = track; | |
346 | attr.inherit = (cpu < 0) && inherit; | |
16c8a109 PZ |
347 | |
348 | track = 0; // only the first counter needs these | |
349 | ||
350 | fd[nr_cpu][counter] = | |
c70975bc | 351 | sys_perf_counter_open(&attr, pid, cpu, group_fd, 0); |
16c8a109 PZ |
352 | |
353 | if (fd[nr_cpu][counter] < 0) { | |
354 | int err = errno; | |
355 | printf("kerneltop error: syscall returned with %d (%s)\n", | |
356 | fd[nr_cpu][counter], strerror(err)); | |
357 | if (err == EPERM) | |
358 | printf("Are you root?\n"); | |
359 | exit(-1); | |
360 | } | |
361 | assert(fd[nr_cpu][counter] >= 0); | |
362 | fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK); | |
363 | ||
364 | /* | |
365 | * First counter acts as the group leader: | |
366 | */ | |
367 | if (group && group_fd == -1) | |
368 | group_fd = fd[nr_cpu][counter]; | |
369 | ||
370 | event_array[nr_poll].fd = fd[nr_cpu][counter]; | |
371 | event_array[nr_poll].events = POLLIN; | |
372 | nr_poll++; | |
373 | ||
374 | mmap_array[nr_cpu][counter].counter = counter; | |
375 | mmap_array[nr_cpu][counter].prev = 0; | |
376 | mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1; | |
377 | mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size, | |
378 | PROT_READ, MAP_SHARED, fd[nr_cpu][counter], 0); | |
379 | if (mmap_array[nr_cpu][counter].base == MAP_FAILED) { | |
380 | printf("kerneltop error: failed to mmap with %d (%s)\n", | |
381 | errno, strerror(errno)); | |
382 | exit(-1); | |
383 | } | |
384 | } | |
385 | nr_cpu++; | |
386 | } | |
387 | ||
0e9b20b8 | 388 | static int __cmd_record(int argc, const char **argv) |
16c8a109 PZ |
389 | { |
390 | int i, counter; | |
abaff32a | 391 | struct stat st; |
de9ac07b | 392 | pid_t pid; |
abaff32a | 393 | int flags; |
de9ac07b PZ |
394 | int ret; |
395 | ||
396 | page_size = sysconf(_SC_PAGE_SIZE); | |
de9ac07b PZ |
397 | nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); |
398 | assert(nr_cpus <= MAX_NR_CPUS); | |
399 | assert(nr_cpus >= 0); | |
400 | ||
abaff32a IM |
401 | if (!stat(output_name, &st) && !force && !append_file) { |
402 | fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n", | |
97124d5e PZ |
403 | output_name); |
404 | exit(-1); | |
405 | } | |
406 | ||
abaff32a IM |
407 | flags = O_CREAT|O_RDWR; |
408 | if (append_file) | |
409 | flags |= O_APPEND; | |
410 | else | |
411 | flags |= O_TRUNC; | |
412 | ||
413 | output = open(output_name, flags, S_IRUSR|S_IWUSR); | |
de9ac07b PZ |
414 | if (output < 0) { |
415 | perror("failed to create output file"); | |
416 | exit(-1); | |
417 | } | |
418 | ||
1a853e36 ACM |
419 | if (!system_wide) { |
420 | open_counters(-1, target_pid != -1 ? target_pid : 0); | |
421 | } else for (i = 0; i < nr_cpus; i++) | |
422 | open_counters(i, target_pid); | |
de9ac07b | 423 | |
16c8a109 PZ |
424 | signal(SIGCHLD, sig_handler); |
425 | signal(SIGINT, sig_handler); | |
de9ac07b | 426 | |
ef65b2a0 | 427 | if (target_pid == -1 && argc) { |
1a853e36 ACM |
428 | pid = fork(); |
429 | if (pid < 0) | |
430 | perror("failed to fork"); | |
de9ac07b | 431 | |
1a853e36 | 432 | if (!pid) { |
0e9b20b8 | 433 | if (execvp(argv[0], (char **)argv)) { |
1a853e36 ACM |
434 | perror(argv[0]); |
435 | exit(-1); | |
436 | } | |
de9ac07b PZ |
437 | } |
438 | } | |
439 | ||
440 | if (realtime_prio) { | |
441 | struct sched_param param; | |
442 | ||
443 | param.sched_priority = realtime_prio; | |
444 | if (sched_setscheduler(0, SCHED_FIFO, ¶m)) { | |
445 | printf("Could not set realtime priority.\n"); | |
446 | exit(-1); | |
447 | } | |
448 | } | |
449 | ||
f70e87d7 PZ |
450 | if (system_wide) |
451 | synthesize_events(); | |
de9ac07b PZ |
452 | |
453 | while (!done) { | |
454 | int hits = events; | |
455 | ||
16c8a109 | 456 | for (i = 0; i < nr_cpu; i++) { |
de9ac07b PZ |
457 | for (counter = 0; counter < nr_counters; counter++) |
458 | mmap_read(&mmap_array[i][counter]); | |
459 | } | |
460 | ||
461 | if (hits == events) | |
462 | ret = poll(event_array, nr_poll, 100); | |
463 | } | |
464 | ||
465 | return 0; | |
466 | } | |
0e9b20b8 | 467 | |
0e9b20b8 | 468 | static const char * const record_usage[] = { |
9e096753 MG |
469 | "perf record [<options>] [<command>]", |
470 | "perf record [<options>] -- <command> [<options>]", | |
0e9b20b8 IM |
471 | NULL |
472 | }; | |
473 | ||
8ad8db37 IM |
474 | static char events_help_msg[EVENTS_HELP_MAX]; |
475 | ||
5242519b | 476 | static const struct option options[] = { |
0e9b20b8 | 477 | OPT_CALLBACK('e', "event", NULL, "event", |
8ad8db37 | 478 | events_help_msg, parse_events), |
0e9b20b8 IM |
479 | OPT_INTEGER('p', "pid", &target_pid, |
480 | "record events on existing pid"), | |
481 | OPT_INTEGER('r', "realtime", &realtime_prio, | |
482 | "collect data with this RT SCHED_FIFO priority"), | |
483 | OPT_BOOLEAN('a', "all-cpus", &system_wide, | |
484 | "system-wide collection from all CPUs"), | |
abaff32a IM |
485 | OPT_BOOLEAN('A', "append", &append_file, |
486 | "append to the output file to do incremental profiling"), | |
97124d5e PZ |
487 | OPT_BOOLEAN('f', "force", &force, |
488 | "overwrite existing data file"), | |
abaff32a IM |
489 | OPT_INTEGER('c', "count", &default_interval, |
490 | "event period to sample"), | |
491 | OPT_STRING('o', "output", &output_name, "file", | |
492 | "output file name"), | |
493 | OPT_BOOLEAN('i', "inherit", &inherit, | |
494 | "child tasks inherit counters"), | |
495 | OPT_INTEGER('m', "mmap-pages", &mmap_pages, | |
496 | "number of mmap data pages"), | |
0e9b20b8 IM |
497 | OPT_END() |
498 | }; | |
499 | ||
500 | int cmd_record(int argc, const char **argv, const char *prefix) | |
501 | { | |
502 | int counter; | |
503 | ||
8ad8db37 | 504 | create_events_help(events_help_msg); |
0e9b20b8 IM |
505 | |
506 | argc = parse_options(argc, argv, options, record_usage, 0); | |
ef65b2a0 | 507 | if (!argc && target_pid == -1 && !system_wide) |
0e9b20b8 IM |
508 | usage_with_options(record_usage, options); |
509 | ||
510 | if (!nr_counters) { | |
511 | nr_counters = 1; | |
512 | event_id[0] = 0; | |
513 | } | |
514 | ||
515 | for (counter = 0; counter < nr_counters; counter++) { | |
516 | if (event_count[counter]) | |
517 | continue; | |
518 | ||
519 | event_count[counter] = default_interval; | |
520 | } | |
521 | ||
522 | return __cmd_record(argc, argv); | |
523 | } |