/* * builtin-stat.c * * Builtin stat command: Give a precise performance counters summary * overview about any workload, CPU or specific PID. * * Sample output: $ perf stat ~/hackbench 10 Time: 0.104 Performance counter stats for '/home/mingo/hackbench': 1255.538611 task clock ticks # 10.143 CPU utilization factor 54011 context switches # 0.043 M/sec 385 CPU migrations # 0.000 M/sec 17755 pagefaults # 0.014 M/sec 3808323185 CPU cycles # 3033.219 M/sec 1575111190 instructions # 1254.530 M/sec 17367895 cache references # 13.833 M/sec 7674421 cache misses # 6.112 M/sec Wall-clock time elapsed: 123.786620 msecs * * Copyright (C) 2008, Red Hat Inc, Ingo Molnar * * Improvements and fixes by: * * Arjan van de Ven * Yanmin Zhang * Wu Fengguang * Mike Galbraith * Paul Mackerras * Jaswinder Singh Rajput * * Released under the GPL v2. (and only v2, not any later version) */ #include "perf.h" #include "builtin.h" #include "util/util.h" #include "util/parse-options.h" #include "util/parse-events.h" #include "util/event.h" #include "util/evlist.h" #include "util/evsel.h" #include "util/debug.h" #include "util/color.h" #include "util/header.h" #include "util/cpumap.h" #include "util/thread.h" #include "util/thread_map.h" #include #include #include #define DEFAULT_SEPARATOR " " static struct perf_event_attr default_attrs[] = { { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_TASK_CLOCK }, { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES }, { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CPU_MIGRATIONS }, { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_PAGE_FAULTS }, { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES }, { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_STALLED_CYCLES }, { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_INSTRUCTIONS }, { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS }, { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_MISSES }, }; struct perf_evlist *evsel_list; static bool system_wide = false; static int run_idx = 0; static int run_count = 1; static bool no_inherit = false; static bool scale = true; static bool no_aggr = false; static pid_t target_pid = -1; static pid_t target_tid = -1; static pid_t child_pid = -1; static bool null_run = false; static bool big_num = true; static int big_num_opt = -1; static const char *cpu_list; static const char *csv_sep = NULL; static bool csv_output = false; static volatile int done = 0; struct stats { double n, mean, M2; }; struct perf_stat { struct stats res_stats[3]; }; static int perf_evsel__alloc_stat_priv(struct perf_evsel *evsel) { evsel->priv = zalloc(sizeof(struct perf_stat)); return evsel->priv == NULL ? -ENOMEM : 0; } static void perf_evsel__free_stat_priv(struct perf_evsel *evsel) { free(evsel->priv); evsel->priv = NULL; } static void update_stats(struct stats *stats, u64 val) { double delta; stats->n++; delta = val - stats->mean; stats->mean += delta / stats->n; stats->M2 += delta*(val - stats->mean); } static double avg_stats(struct stats *stats) { return stats->mean; } /* * http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance * * (\Sum n_i^2) - ((\Sum n_i)^2)/n * s^2 = ------------------------------- * n - 1 * * http://en.wikipedia.org/wiki/Stddev * * The std dev of the mean is related to the std dev by: * * s * s_mean = ------- * sqrt(n) * */ static double stddev_stats(struct stats *stats) { double variance = stats->M2 / (stats->n - 1); double variance_mean = variance / stats->n; return sqrt(variance_mean); } struct stats runtime_nsecs_stats[MAX_NR_CPUS]; struct stats runtime_cycles_stats[MAX_NR_CPUS]; struct stats runtime_stalled_cycles_stats[MAX_NR_CPUS]; struct stats runtime_branches_stats[MAX_NR_CPUS]; struct stats runtime_cacherefs_stats[MAX_NR_CPUS]; struct stats walltime_nsecs_stats; static int create_perf_stat_counter(struct perf_evsel *evsel) { struct perf_event_attr *attr = &evsel->attr; if (scale) attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING; attr->inherit = !no_inherit; if (system_wide) return perf_evsel__open_per_cpu(evsel, evsel_list->cpus, false); if (target_pid == -1 && target_tid == -1) { attr->disabled = 1; attr->enable_on_exec = 1; } return perf_evsel__open_per_thread(evsel, evsel_list->threads, false); } /* * Does the counter have nsecs as a unit? */ static inline int nsec_counter(struct perf_evsel *evsel) { if (perf_evsel__match(evsel, SOFTWARE, SW_CPU_CLOCK) || perf_evsel__match(evsel, SOFTWARE, SW_TASK_CLOCK)) return 1; return 0; } /* * Update various tracking values we maintain to print * more semantic information such as miss/hit ratios, * instruction rates, etc: */ static void update_shadow_stats(struct perf_evsel *counter, u64 *count) { if (perf_evsel__match(counter, SOFTWARE, SW_TASK_CLOCK)) update_stats(&runtime_nsecs_stats[0], count[0]); else if (perf_evsel__match(counter, HARDWARE, HW_CPU_CYCLES)) update_stats(&runtime_cycles_stats[0], count[0]); else if (perf_evsel__match(counter, HARDWARE, HW_STALLED_CYCLES)) update_stats(&runtime_stalled_cycles_stats[0], count[0]); else if (perf_evsel__match(counter, HARDWARE, HW_BRANCH_INSTRUCTIONS)) update_stats(&runtime_branches_stats[0], count[0]); else if (perf_evsel__match(counter, HARDWARE, HW_CACHE_REFERENCES)) update_stats(&runtime_cacherefs_stats[0], count[0]); } /* * Read out the results of a single counter: * aggregate counts across CPUs in system-wide mode */ static int read_counter_aggr(struct perf_evsel *counter) { struct perf_stat *ps = counter->priv; u64 *count = counter->counts->aggr.values; int i; if (__perf_evsel__read(counter, evsel_list->cpus->nr, evsel_list->threads->nr, scale) < 0) return -1; for (i = 0; i < 3; i++) update_stats(&ps->res_stats[i], count[i]); if (verbose) { fprintf(stderr, "%s: %" PRIu64 " %" PRIu64 " %" PRIu64 "\n", event_name(counter), count[0], count[1], count[2]); } /* * Save the full runtime - to allow normalization during printout: */ update_shadow_stats(counter, count); return 0; } /* * Read out the results of a single counter: * do not aggregate counts across CPUs in system-wide mode */ static int read_counter(struct perf_evsel *counter) { u64 *count; int cpu; for (cpu = 0; cpu < evsel_list->cpus->nr; cpu++) { if (__perf_evsel__read_on_cpu(counter, cpu, 0, scale) < 0) return -1; count = counter->counts->cpu[cpu].values; update_shadow_stats(counter, count); } return 0; } static int run_perf_stat(int argc __used, const char **argv) { unsigned long long t0, t1; struct perf_evsel *counter; int status = 0; int child_ready_pipe[2], go_pipe[2]; const bool forks = (argc > 0); char buf; if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) { perror("failed to create pipes"); exit(1); } if (forks) { if ((child_pid = fork()) < 0) perror("failed to fork"); if (!child_pid) { close(child_ready_pipe[0]); close(go_pipe[1]); fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC); /* * Do a dummy execvp to get the PLT entry resolved, * so we avoid the resolver overhead on the real * execvp call. */ execvp("", (char **)argv); /* * Tell the parent we're ready to go */ close(child_ready_pipe[1]); /* * Wait until the parent tells us to go. */ if (read(go_pipe[0], &buf, 1) == -1) perror("unable to read pipe"); execvp(argv[0], (char **)argv); perror(argv[0]); exit(-1); } if (target_tid == -1 && target_pid == -1 && !system_wide) evsel_list->threads->map[0] = child_pid; /* * Wait for the child to be ready to exec. */ close(child_ready_pipe[1]); close(go_pipe[0]); if (read(child_ready_pipe[0], &buf, 1) == -1) perror("unable to read pipe"); close(child_ready_pipe[0]); } list_for_each_entry(counter, &evsel_list->entries, node) { if (create_perf_stat_counter(counter) < 0) { if (errno == -EPERM || errno == -EACCES) { error("You may not have permission to collect %sstats.\n" "\t Consider tweaking" " /proc/sys/kernel/perf_event_paranoid or running as root.", system_wide ? "system-wide " : ""); } else if (errno == ENOENT) { error("%s event is not supported. ", event_name(counter)); } else { error("open_counter returned with %d (%s). " "/bin/dmesg may provide additional information.\n", errno, strerror(errno)); } if (child_pid != -1) kill(child_pid, SIGTERM); die("Not all events could be opened.\n"); return -1; } } if (perf_evlist__set_filters(evsel_list)) { error("failed to set filter with %d (%s)\n", errno, strerror(errno)); return -1; } /* * Enable counters and exec the command: */ t0 = rdclock(); if (forks) { close(go_pipe[1]); wait(&status); } else { while(!done) sleep(1); } t1 = rdclock(); update_stats(&walltime_nsecs_stats, t1 - t0); if (no_aggr) { list_for_each_entry(counter, &evsel_list->entries, node) { read_counter(counter); perf_evsel__close_fd(counter, evsel_list->cpus->nr, 1); } } else { list_for_each_entry(counter, &evsel_list->entries, node) { read_counter_aggr(counter); perf_evsel__close_fd(counter, evsel_list->cpus->nr, evsel_list->threads->nr); } } return WEXITSTATUS(status); } static void print_noise_pct(double total, double avg) { double pct = 0.0; if (avg) pct = 100.0*total/avg; fprintf(stderr, " ( +-%6.2f%% )", pct); } static void print_noise(struct perf_evsel *evsel, double avg) { struct perf_stat *ps; if (run_count == 1) return; ps = evsel->priv; print_noise_pct(stddev_stats(&ps->res_stats[0]), avg); } static void nsec_printout(int cpu, struct perf_evsel *evsel, double avg) { double msecs = avg / 1e6; char cpustr[16] = { '\0', }; const char *fmt = csv_output ? "%s%.6f%s%s" : "%s%18.6f%s%-24s"; if (no_aggr) sprintf(cpustr, "CPU%*d%s", csv_output ? 0 : -4, evsel_list->cpus->map[cpu], csv_sep); fprintf(stderr, fmt, cpustr, msecs, csv_sep, event_name(evsel)); if (evsel->cgrp) fprintf(stderr, "%s%s", csv_sep, evsel->cgrp->name); if (csv_output) return; if (perf_evsel__match(evsel, SOFTWARE, SW_TASK_CLOCK)) fprintf(stderr, " # %8.3f CPUs utilized ", avg / avg_stats(&walltime_nsecs_stats)); } static void print_stalled_cycles(int cpu, struct perf_evsel *evsel __used, double avg) { double total, ratio = 0.0; const char *color; total = avg_stats(&runtime_cycles_stats[cpu]); if (total) ratio = avg / total * 100.0; color = PERF_COLOR_NORMAL; if (ratio > 75.0) color = PERF_COLOR_RED; else if (ratio > 50.0) color = PERF_COLOR_MAGENTA; else if (ratio > 25.0) color = PERF_COLOR_YELLOW; fprintf(stderr, " # "); color_fprintf(stderr, color, "%5.2f%%", ratio); fprintf(stderr, " of all cycles are idle "); } static void abs_printout(int cpu, struct perf_evsel *evsel, double avg) { double total, ratio = 0.0; char cpustr[16] = { '\0', }; const char *fmt; if (csv_output) fmt = "%s%.0f%s%s"; else if (big_num) fmt = "%s%'18.0f%s%-24s"; else fmt = "%s%18.0f%s%-24s"; if (no_aggr) sprintf(cpustr, "CPU%*d%s", csv_output ? 0 : -4, evsel_list->cpus->map[cpu], csv_sep); else cpu = 0; fprintf(stderr, fmt, cpustr, avg, csv_sep, event_name(evsel)); if (evsel->cgrp) fprintf(stderr, "%s%s", csv_sep, evsel->cgrp->name); if (csv_output) return; if (perf_evsel__match(evsel, HARDWARE, HW_INSTRUCTIONS)) { total = avg_stats(&runtime_cycles_stats[cpu]); if (total) ratio = avg / total; fprintf(stderr, " # %4.2f insns per cycle", ratio); total = avg_stats(&runtime_stalled_cycles_stats[cpu]); if (total && avg) { ratio = total / avg; fprintf(stderr, "\n # %4.2f stalled cycles per insn", ratio); } } else if (perf_evsel__match(evsel, HARDWARE, HW_BRANCH_MISSES) && runtime_branches_stats[cpu].n != 0) { total = avg_stats(&runtime_branches_stats[cpu]); if (total) ratio = avg * 100 / total; fprintf(stderr, " # %5.2f %% of all branches ", ratio); } else if (perf_evsel__match(evsel, HARDWARE, HW_CACHE_MISSES) && runtime_cacherefs_stats[cpu].n != 0) { total = avg_stats(&runtime_cacherefs_stats[cpu]); if (total) ratio = avg * 100 / total; fprintf(stderr, " # %8.3f %% of all cache refs ", ratio); } else if (perf_evsel__match(evsel, HARDWARE, HW_STALLED_CYCLES)) { print_stalled_cycles(cpu, evsel, avg); } else if (perf_evsel__match(evsel, HARDWARE, HW_CPU_CYCLES)) { total = avg_stats(&runtime_nsecs_stats[cpu]); if (total) ratio = 1.0 * avg / total; fprintf(stderr, " # %8.3f GHz ", ratio); } else if (runtime_nsecs_stats[cpu].n != 0) { total = avg_stats(&runtime_nsecs_stats[cpu]); if (total) ratio = 1000.0 * avg / total; fprintf(stderr, " # %8.3f M/sec ", ratio); } else { fprintf(stderr, " "); } } /* * Print out the results of a single counter: * aggregated counts in system-wide mode */ static void print_counter_aggr(struct perf_evsel *counter) { struct perf_stat *ps = counter->priv; double avg = avg_stats(&ps->res_stats[0]); int scaled = counter->counts->scaled; if (scaled == -1) { fprintf(stderr, "%*s%s%*s", csv_output ? 0 : 18, "", csv_sep, csv_output ? 0 : -24, event_name(counter)); if (counter->cgrp) fprintf(stderr, "%s%s", csv_sep, counter->cgrp->name); fputc('\n', stderr); return; } if (nsec_counter(counter)) nsec_printout(-1, counter, avg); else abs_printout(-1, counter, avg); if (csv_output) { fputc('\n', stderr); return; } print_noise(counter, avg); if (scaled) { double avg_enabled, avg_running; avg_enabled = avg_stats(&ps->res_stats[1]); avg_running = avg_stats(&ps->res_stats[2]); fprintf(stderr, " (scaled from %.2f%%)", 100 * avg_running / avg_enabled); } fprintf(stderr, "\n"); } /* * Print out the results of a single counter: * does not use aggregated count in system-wide */ static void print_counter(struct perf_evsel *counter) { u64 ena, run, val; int cpu; for (cpu = 0; cpu < evsel_list->cpus->nr; cpu++) { val = counter->counts->cpu[cpu].val; ena = counter->counts->cpu[cpu].ena; run = counter->counts->cpu[cpu].run; if (run == 0 || ena == 0) { fprintf(stderr, "CPU%*d%s%*s%s%*s", csv_output ? 0 : -4, evsel_list->cpus->map[cpu], csv_sep, csv_output ? 0 : 18, "", csv_sep, csv_output ? 0 : -24, event_name(counter)); if (counter->cgrp) fprintf(stderr, "%s%s", csv_sep, counter->cgrp->name); fputc('\n', stderr); continue; } if (nsec_counter(counter)) nsec_printout(cpu, counter, val); else abs_printout(cpu, counter, val); if (!csv_output) { print_noise(counter, 1.0); if (run != ena) { fprintf(stderr, " (scaled from %.2f%%)", 100.0 * run / ena); } } fputc('\n', stderr); } } static void print_stat(int argc, const char **argv) { struct perf_evsel *counter; int i; fflush(stdout); if (!csv_output) { fprintf(stderr, "\n"); fprintf(stderr, " Performance counter stats for "); if(target_pid == -1 && target_tid == -1) { fprintf(stderr, "\'%s", argv[0]); for (i = 1; i < argc; i++) fprintf(stderr, " %s", argv[i]); } else if (target_pid != -1) fprintf(stderr, "process id \'%d", target_pid); else fprintf(stderr, "thread id \'%d", target_tid); fprintf(stderr, "\'"); if (run_count > 1) fprintf(stderr, " (%d runs)", run_count); fprintf(stderr, ":\n\n"); } if (no_aggr) { list_for_each_entry(counter, &evsel_list->entries, node) print_counter(counter); } else { list_for_each_entry(counter, &evsel_list->entries, node) print_counter_aggr(counter); } if (!csv_output) { fprintf(stderr, "\n"); fprintf(stderr, " %18.9f seconds time elapsed", avg_stats(&walltime_nsecs_stats)/1e9); if (run_count > 1) { print_noise_pct(stddev_stats(&walltime_nsecs_stats), avg_stats(&walltime_nsecs_stats)); } fprintf(stderr, "\n\n"); } } static volatile int signr = -1; static void skip_signal(int signo) { if(child_pid == -1) done = 1; signr = signo; } static void sig_atexit(void) { if (child_pid != -1) kill(child_pid, SIGTERM); if (signr == -1) return; signal(signr, SIG_DFL); kill(getpid(), signr); } static const char * const stat_usage[] = { "perf stat [] []", NULL }; static int stat__set_big_num(const struct option *opt __used, const char *s __used, int unset) { big_num_opt = unset ? 0 : 1; return 0; } static const struct option options[] = { OPT_CALLBACK('e', "event", &evsel_list, "event", "event selector. use 'perf list' to list available events", parse_events), OPT_CALLBACK(0, "filter", &evsel_list, "filter", "event filter", parse_filter), OPT_BOOLEAN('i', "no-inherit", &no_inherit, "child tasks do not inherit counters"), OPT_INTEGER('p', "pid", &target_pid, "stat events on existing process id"), OPT_INTEGER('t', "tid", &target_tid, "stat events on existing thread id"), OPT_BOOLEAN('a', "all-cpus", &system_wide, "system-wide collection from all CPUs"), OPT_BOOLEAN('c', "scale", &scale, "scale/normalize counters"), OPT_INCR('v', "verbose", &verbose, "be more verbose (show counter open errors, etc)"), OPT_INTEGER('r', "repeat", &run_count, "repeat command and print average + stddev (max: 100)"), OPT_BOOLEAN('n', "null", &null_run, "null run - dont start any counters"), OPT_CALLBACK_NOOPT('B', "big-num", NULL, NULL, "print large numbers with thousands\' separators", stat__set_big_num), OPT_STRING('C', "cpu", &cpu_list, "cpu", "list of cpus to monitor in system-wide"), OPT_BOOLEAN('A', "no-aggr", &no_aggr, "disable CPU count aggregation"), OPT_STRING('x', "field-separator", &csv_sep, "separator", "print counts with custom separator"), OPT_CALLBACK('G', "cgroup", &evsel_list, "name", "monitor event in cgroup name only", parse_cgroups), OPT_END() }; int cmd_stat(int argc, const char **argv, const char *prefix __used) { struct perf_evsel *pos; int status = -ENOMEM; setlocale(LC_ALL, ""); evsel_list = perf_evlist__new(NULL, NULL); if (evsel_list == NULL) return -ENOMEM; argc = parse_options(argc, argv, options, stat_usage, PARSE_OPT_STOP_AT_NON_OPTION); if (csv_sep) csv_output = true; else csv_sep = DEFAULT_SEPARATOR; /* * let the spreadsheet do the pretty-printing */ if (csv_output) { /* User explicitely passed -B? */ if (big_num_opt == 1) { fprintf(stderr, "-B option not supported with -x\n"); usage_with_options(stat_usage, options); } else /* Nope, so disable big number formatting */ big_num = false; } else if (big_num_opt == 0) /* User passed --no-big-num */ big_num = false; if (!argc && target_pid == -1 && target_tid == -1) usage_with_options(stat_usage, options); if (run_count <= 0) usage_with_options(stat_usage, options); /* no_aggr, cgroup are for system-wide only */ if ((no_aggr || nr_cgroups) && !system_wide) { fprintf(stderr, "both cgroup and no-aggregation " "modes only available in system-wide mode\n"); usage_with_options(stat_usage, options); } /* Set attrs and nr_counters if no event is selected and !null_run */ if (!null_run && !evsel_list->nr_entries) { size_t c; for (c = 0; c < ARRAY_SIZE(default_attrs); ++c) { pos = perf_evsel__new(&default_attrs[c], c); if (pos == NULL) goto out; perf_evlist__add(evsel_list, pos); } } if (target_pid != -1) target_tid = target_pid; evsel_list->threads = thread_map__new(target_pid, target_tid); if (evsel_list->threads == NULL) { pr_err("Problems finding threads of monitor\n"); usage_with_options(stat_usage, options); } if (system_wide) evsel_list->cpus = cpu_map__new(cpu_list); else evsel_list->cpus = cpu_map__dummy_new(); if (evsel_list->cpus == NULL) { perror("failed to parse CPUs map"); usage_with_options(stat_usage, options); return -1; } list_for_each_entry(pos, &evsel_list->entries, node) { if (perf_evsel__alloc_stat_priv(pos) < 0 || perf_evsel__alloc_counts(pos, evsel_list->cpus->nr) < 0 || perf_evsel__alloc_fd(pos, evsel_list->cpus->nr, evsel_list->threads->nr) < 0) goto out_free_fd; } /* * We dont want to block the signals - that would cause * child tasks to inherit that and Ctrl-C would not work. * What we want is for Ctrl-C to work in the exec()-ed * task, but being ignored by perf stat itself: */ atexit(sig_atexit); signal(SIGINT, skip_signal); signal(SIGALRM, skip_signal); signal(SIGABRT, skip_signal); status = 0; for (run_idx = 0; run_idx < run_count; run_idx++) { if (run_count != 1 && verbose) fprintf(stderr, "[ perf stat: executing run #%d ... ]\n", run_idx + 1); status = run_perf_stat(argc, argv); } if (status != -1) print_stat(argc, argv); out_free_fd: list_for_each_entry(pos, &evsel_list->entries, node) perf_evsel__free_stat_priv(pos); perf_evlist__delete_maps(evsel_list); out: perf_evlist__delete(evsel_list); return status; }