perf_counter: Provide a way to enable counters on exec
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / tools / perf / builtin-stat.c
blob2e03524a1de0a863c85be35553b66415ab502569
1 /*
2 * builtin-stat.c
4 * Builtin stat command: Give a precise performance counters summary
5 * overview about any workload, CPU or specific PID.
7 * Sample output:
9 $ perf stat ~/hackbench 10
10 Time: 0.104
12 Performance counter stats for '/home/mingo/hackbench':
14 1255.538611 task clock ticks # 10.143 CPU utilization factor
15 54011 context switches # 0.043 M/sec
16 385 CPU migrations # 0.000 M/sec
17 17755 pagefaults # 0.014 M/sec
18 3808323185 CPU cycles # 3033.219 M/sec
19 1575111190 instructions # 1254.530 M/sec
20 17367895 cache references # 13.833 M/sec
21 7674421 cache misses # 6.112 M/sec
23 Wall-clock time elapsed: 123.786620 msecs
26 * Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
28 * Improvements and fixes by:
30 * Arjan van de Ven <arjan@linux.intel.com>
31 * Yanmin Zhang <yanmin.zhang@intel.com>
32 * Wu Fengguang <fengguang.wu@intel.com>
33 * Mike Galbraith <efault@gmx.de>
34 * Paul Mackerras <paulus@samba.org>
35 * Jaswinder Singh Rajput <jaswinder@kernel.org>
37 * Released under the GPL v2. (and only v2, not any later version)
40 #include "perf.h"
41 #include "builtin.h"
42 #include "util/util.h"
43 #include "util/parse-options.h"
44 #include "util/parse-events.h"
46 #include <sys/prctl.h>
47 #include <math.h>
49 static struct perf_counter_attr default_attrs[] = {
51 { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_TASK_CLOCK },
52 { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES},
53 { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CPU_MIGRATIONS },
54 { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_PAGE_FAULTS },
56 { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES },
57 { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_INSTRUCTIONS },
58 { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CACHE_REFERENCES},
59 { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CACHE_MISSES },
63 #define MAX_RUN 100
65 static int system_wide = 0;
66 static int verbose = 0;
67 static int nr_cpus = 0;
68 static int run_idx = 0;
70 static int run_count = 1;
71 static int inherit = 1;
72 static int scale = 1;
73 static int target_pid = -1;
74 static int null_run = 0;
76 static int fd[MAX_NR_CPUS][MAX_COUNTERS];
78 static u64 runtime_nsecs[MAX_RUN];
79 static u64 walltime_nsecs[MAX_RUN];
80 static u64 runtime_cycles[MAX_RUN];
82 static u64 event_res[MAX_RUN][MAX_COUNTERS][3];
83 static u64 event_scaled[MAX_RUN][MAX_COUNTERS];
85 static u64 event_res_avg[MAX_COUNTERS][3];
86 static u64 event_res_noise[MAX_COUNTERS][3];
88 static u64 event_scaled_avg[MAX_COUNTERS];
90 static u64 runtime_nsecs_avg;
91 static u64 runtime_nsecs_noise;
93 static u64 walltime_nsecs_avg;
94 static u64 walltime_nsecs_noise;
96 static u64 runtime_cycles_avg;
97 static u64 runtime_cycles_noise;
99 #define ERR_PERF_OPEN \
100 "Error: counter %d, sys_perf_counter_open() syscall returned with %d (%s)\n"
102 static void create_perf_stat_counter(int counter, int pid)
104 struct perf_counter_attr *attr = attrs + counter;
106 if (scale)
107 attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
108 PERF_FORMAT_TOTAL_TIME_RUNNING;
110 if (system_wide) {
111 int cpu;
112 for (cpu = 0; cpu < nr_cpus; cpu++) {
113 fd[cpu][counter] = sys_perf_counter_open(attr, -1, cpu, -1, 0);
114 if (fd[cpu][counter] < 0 && verbose)
115 fprintf(stderr, ERR_PERF_OPEN, counter,
116 fd[cpu][counter], strerror(errno));
118 } else {
119 attr->inherit = inherit;
120 attr->disabled = 1;
121 attr->enable_on_exec = 1;
123 fd[0][counter] = sys_perf_counter_open(attr, pid, -1, -1, 0);
124 if (fd[0][counter] < 0 && verbose)
125 fprintf(stderr, ERR_PERF_OPEN, counter,
126 fd[0][counter], strerror(errno));
131 * Does the counter have nsecs as a unit?
133 static inline int nsec_counter(int counter)
135 if (attrs[counter].type != PERF_TYPE_SOFTWARE)
136 return 0;
138 if (attrs[counter].config == PERF_COUNT_SW_CPU_CLOCK)
139 return 1;
141 if (attrs[counter].config == PERF_COUNT_SW_TASK_CLOCK)
142 return 1;
144 return 0;
148 * Read out the results of a single counter:
150 static void read_counter(int counter)
152 u64 *count, single_count[3];
153 ssize_t res;
154 int cpu, nv;
155 int scaled;
157 count = event_res[run_idx][counter];
159 count[0] = count[1] = count[2] = 0;
161 nv = scale ? 3 : 1;
162 for (cpu = 0; cpu < nr_cpus; cpu++) {
163 if (fd[cpu][counter] < 0)
164 continue;
166 res = read(fd[cpu][counter], single_count, nv * sizeof(u64));
167 assert(res == nv * sizeof(u64));
168 close(fd[cpu][counter]);
169 fd[cpu][counter] = -1;
171 count[0] += single_count[0];
172 if (scale) {
173 count[1] += single_count[1];
174 count[2] += single_count[2];
178 scaled = 0;
179 if (scale) {
180 if (count[2] == 0) {
181 event_scaled[run_idx][counter] = -1;
182 count[0] = 0;
183 return;
186 if (count[2] < count[1]) {
187 event_scaled[run_idx][counter] = 1;
188 count[0] = (unsigned long long)
189 ((double)count[0] * count[1] / count[2] + 0.5);
193 * Save the full runtime - to allow normalization during printout:
195 if (attrs[counter].type == PERF_TYPE_SOFTWARE &&
196 attrs[counter].config == PERF_COUNT_SW_TASK_CLOCK)
197 runtime_nsecs[run_idx] = count[0];
198 if (attrs[counter].type == PERF_TYPE_HARDWARE &&
199 attrs[counter].config == PERF_COUNT_HW_CPU_CYCLES)
200 runtime_cycles[run_idx] = count[0];
203 static int run_perf_stat(int argc, const char **argv)
205 unsigned long long t0, t1;
206 int status = 0;
207 int counter;
208 int pid;
209 int child_ready_pipe[2], go_pipe[2];
210 char buf;
212 if (!system_wide)
213 nr_cpus = 1;
215 if (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0) {
216 perror("failed to create pipes");
217 exit(1);
220 if ((pid = fork()) < 0)
221 perror("failed to fork");
223 if (!pid) {
224 close(child_ready_pipe[0]);
225 close(go_pipe[1]);
226 fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
229 * Do a dummy execvp to get the PLT entry resolved,
230 * so we avoid the resolver overhead on the real
231 * execvp call.
233 execvp("", (char **)argv);
236 * Tell the parent we're ready to go
238 close(child_ready_pipe[1]);
241 * Wait until the parent tells us to go.
243 read(go_pipe[0], &buf, 1);
245 execvp(argv[0], (char **)argv);
247 perror(argv[0]);
248 exit(-1);
252 * Wait for the child to be ready to exec.
254 close(child_ready_pipe[1]);
255 close(go_pipe[0]);
256 read(child_ready_pipe[0], &buf, 1);
257 close(child_ready_pipe[0]);
259 for (counter = 0; counter < nr_counters; counter++)
260 create_perf_stat_counter(counter, pid);
263 * Enable counters and exec the command:
265 t0 = rdclock();
267 close(go_pipe[1]);
268 wait(&status);
270 t1 = rdclock();
272 walltime_nsecs[run_idx] = t1 - t0;
274 for (counter = 0; counter < nr_counters; counter++)
275 read_counter(counter);
277 return WEXITSTATUS(status);
280 static void print_noise(u64 *count, u64 *noise)
282 if (run_count > 1)
283 fprintf(stderr, " ( +- %7.3f%% )",
284 (double)noise[0]/(count[0]+1)*100.0);
287 static void nsec_printout(int counter, u64 *count, u64 *noise)
289 double msecs = (double)count[0] / 1000000;
291 fprintf(stderr, " %14.6f %-24s", msecs, event_name(counter));
293 if (attrs[counter].type == PERF_TYPE_SOFTWARE &&
294 attrs[counter].config == PERF_COUNT_SW_TASK_CLOCK) {
296 if (walltime_nsecs_avg)
297 fprintf(stderr, " # %10.3f CPUs ",
298 (double)count[0] / (double)walltime_nsecs_avg);
300 print_noise(count, noise);
303 static void abs_printout(int counter, u64 *count, u64 *noise)
305 fprintf(stderr, " %14Ld %-24s", count[0], event_name(counter));
307 if (runtime_cycles_avg &&
308 attrs[counter].type == PERF_TYPE_HARDWARE &&
309 attrs[counter].config == PERF_COUNT_HW_INSTRUCTIONS) {
311 fprintf(stderr, " # %10.3f IPC ",
312 (double)count[0] / (double)runtime_cycles_avg);
313 } else {
314 if (runtime_nsecs_avg) {
315 fprintf(stderr, " # %10.3f M/sec",
316 (double)count[0]/runtime_nsecs_avg*1000.0);
319 print_noise(count, noise);
323 * Print out the results of a single counter:
325 static void print_counter(int counter)
327 u64 *count, *noise;
328 int scaled;
330 count = event_res_avg[counter];
331 noise = event_res_noise[counter];
332 scaled = event_scaled_avg[counter];
334 if (scaled == -1) {
335 fprintf(stderr, " %14s %-24s\n",
336 "<not counted>", event_name(counter));
337 return;
340 if (nsec_counter(counter))
341 nsec_printout(counter, count, noise);
342 else
343 abs_printout(counter, count, noise);
345 if (scaled)
346 fprintf(stderr, " (scaled from %.2f%%)",
347 (double) count[2] / count[1] * 100);
349 fprintf(stderr, "\n");
353 * normalize_noise noise values down to stddev:
355 static void normalize_noise(u64 *val)
357 double res;
359 res = (double)*val / (run_count * sqrt((double)run_count));
361 *val = (u64)res;
364 static void update_avg(const char *name, int idx, u64 *avg, u64 *val)
366 *avg += *val;
368 if (verbose > 1)
369 fprintf(stderr, "debug: %20s[%d]: %Ld\n", name, idx, *val);
372 * Calculate the averages and noises:
374 static void calc_avg(void)
376 int i, j;
378 if (verbose > 1)
379 fprintf(stderr, "\n");
381 for (i = 0; i < run_count; i++) {
382 update_avg("runtime", 0, &runtime_nsecs_avg, runtime_nsecs + i);
383 update_avg("walltime", 0, &walltime_nsecs_avg, walltime_nsecs + i);
384 update_avg("runtime_cycles", 0, &runtime_cycles_avg, runtime_cycles + i);
386 for (j = 0; j < nr_counters; j++) {
387 update_avg("counter/0", j,
388 event_res_avg[j]+0, event_res[i][j]+0);
389 update_avg("counter/1", j,
390 event_res_avg[j]+1, event_res[i][j]+1);
391 update_avg("counter/2", j,
392 event_res_avg[j]+2, event_res[i][j]+2);
393 if (event_scaled[i][j] != -1)
394 update_avg("scaled", j,
395 event_scaled_avg + j, event_scaled[i]+j);
396 else
397 event_scaled_avg[j] = -1;
400 runtime_nsecs_avg /= run_count;
401 walltime_nsecs_avg /= run_count;
402 runtime_cycles_avg /= run_count;
404 for (j = 0; j < nr_counters; j++) {
405 event_res_avg[j][0] /= run_count;
406 event_res_avg[j][1] /= run_count;
407 event_res_avg[j][2] /= run_count;
410 for (i = 0; i < run_count; i++) {
411 runtime_nsecs_noise +=
412 abs((s64)(runtime_nsecs[i] - runtime_nsecs_avg));
413 walltime_nsecs_noise +=
414 abs((s64)(walltime_nsecs[i] - walltime_nsecs_avg));
415 runtime_cycles_noise +=
416 abs((s64)(runtime_cycles[i] - runtime_cycles_avg));
418 for (j = 0; j < nr_counters; j++) {
419 event_res_noise[j][0] +=
420 abs((s64)(event_res[i][j][0] - event_res_avg[j][0]));
421 event_res_noise[j][1] +=
422 abs((s64)(event_res[i][j][1] - event_res_avg[j][1]));
423 event_res_noise[j][2] +=
424 abs((s64)(event_res[i][j][2] - event_res_avg[j][2]));
428 normalize_noise(&runtime_nsecs_noise);
429 normalize_noise(&walltime_nsecs_noise);
430 normalize_noise(&runtime_cycles_noise);
432 for (j = 0; j < nr_counters; j++) {
433 normalize_noise(&event_res_noise[j][0]);
434 normalize_noise(&event_res_noise[j][1]);
435 normalize_noise(&event_res_noise[j][2]);
439 static void print_stat(int argc, const char **argv)
441 int i, counter;
443 calc_avg();
445 fflush(stdout);
447 fprintf(stderr, "\n");
448 fprintf(stderr, " Performance counter stats for \'%s", argv[0]);
450 for (i = 1; i < argc; i++)
451 fprintf(stderr, " %s", argv[i]);
453 fprintf(stderr, "\'");
454 if (run_count > 1)
455 fprintf(stderr, " (%d runs)", run_count);
456 fprintf(stderr, ":\n\n");
458 for (counter = 0; counter < nr_counters; counter++)
459 print_counter(counter);
461 fprintf(stderr, "\n");
462 fprintf(stderr, " %14.9f seconds time elapsed",
463 (double)walltime_nsecs_avg/1e9);
464 if (run_count > 1) {
465 fprintf(stderr, " ( +- %7.3f%% )",
466 100.0*(double)walltime_nsecs_noise/(double)walltime_nsecs_avg);
468 fprintf(stderr, "\n\n");
471 static volatile int signr = -1;
473 static void skip_signal(int signo)
475 signr = signo;
478 static void sig_atexit(void)
480 if (signr == -1)
481 return;
483 signal(signr, SIG_DFL);
484 kill(getpid(), signr);
487 static const char * const stat_usage[] = {
488 "perf stat [<options>] <command>",
489 NULL
492 static const struct option options[] = {
493 OPT_CALLBACK('e', "event", NULL, "event",
494 "event selector. use 'perf list' to list available events",
495 parse_events),
496 OPT_BOOLEAN('i', "inherit", &inherit,
497 "child tasks inherit counters"),
498 OPT_INTEGER('p', "pid", &target_pid,
499 "stat events on existing pid"),
500 OPT_BOOLEAN('a', "all-cpus", &system_wide,
501 "system-wide collection from all CPUs"),
502 OPT_BOOLEAN('S', "scale", &scale,
503 "scale/normalize counters"),
504 OPT_BOOLEAN('v', "verbose", &verbose,
505 "be more verbose (show counter open errors, etc)"),
506 OPT_INTEGER('r', "repeat", &run_count,
507 "repeat command and print average + stddev (max: 100)"),
508 OPT_BOOLEAN('n', "null", &null_run,
509 "null run - dont start any counters"),
510 OPT_END()
513 int cmd_stat(int argc, const char **argv, const char *prefix)
515 int status;
517 argc = parse_options(argc, argv, options, stat_usage, 0);
518 if (!argc)
519 usage_with_options(stat_usage, options);
520 if (run_count <= 0 || run_count > MAX_RUN)
521 usage_with_options(stat_usage, options);
523 /* Set attrs and nr_counters if no event is selected and !null_run */
524 if (!null_run && !nr_counters) {
525 memcpy(attrs, default_attrs, sizeof(default_attrs));
526 nr_counters = ARRAY_SIZE(default_attrs);
529 nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
530 assert(nr_cpus <= MAX_NR_CPUS);
531 assert(nr_cpus >= 0);
534 * We dont want to block the signals - that would cause
535 * child tasks to inherit that and Ctrl-C would not work.
536 * What we want is for Ctrl-C to work in the exec()-ed
537 * task, but being ignored by perf stat itself:
539 atexit(sig_atexit);
540 signal(SIGINT, skip_signal);
541 signal(SIGALRM, skip_signal);
542 signal(SIGABRT, skip_signal);
544 status = 0;
545 for (run_idx = 0; run_idx < run_count; run_idx++) {
546 if (run_count != 1 && verbose)
547 fprintf(stderr, "[ perf stat: executing run #%d ... ]\n", run_idx + 1);
548 status = run_perf_stat(argc, argv);
551 print_stat(argc, argv);
553 return status;