brintos

brintos / linux-shallow public Read only

0
0
Text · 2.3 KiB · bc142f0 Raw
120 lines · c
1#include <linux/perf_event.h>2#include <perf/evlist.h>3#include <perf/evsel.h>4#include <perf/cpumap.h>5#include <perf/threadmap.h>6#include <perf/mmap.h>7#include <perf/core.h>8#include <perf/event.h>9#include <stdio.h>10#include <unistd.h>11 12static int libperf_print(enum libperf_print_level level,13                         const char *fmt, va_list ap)14{15	return vfprintf(stderr, fmt, ap);16}17 18union u64_swap {19	__u64 val64;20	__u32 val32[2];21};22 23int main(int argc, char **argv)24{25	struct perf_evlist *evlist;26	struct perf_evsel *evsel;27	struct perf_mmap *map;28	struct perf_cpu_map *cpus;29	struct perf_event_attr attr = {30		.type        = PERF_TYPE_HARDWARE,31		.config      = PERF_COUNT_HW_CPU_CYCLES,32		.disabled    = 1,33		.freq        = 1,34		.sample_freq = 10,35		.sample_type = PERF_SAMPLE_IP|PERF_SAMPLE_TID|PERF_SAMPLE_CPU|PERF_SAMPLE_PERIOD,36	};37	int err = -1;38	union perf_event *event;39 40	libperf_init(libperf_print);41 42	cpus = perf_cpu_map__new_online_cpus();43	if (!cpus) {44		fprintf(stderr, "failed to create cpus\n");45		return -1;46	}47 48	evlist = perf_evlist__new();49	if (!evlist) {50		fprintf(stderr, "failed to create evlist\n");51		goto out_cpus;52	}53 54	evsel = perf_evsel__new(&attr);55	if (!evsel) {56		fprintf(stderr, "failed to create cycles\n");57		goto out_cpus;58	}59 60	perf_evlist__add(evlist, evsel);61 62	perf_evlist__set_maps(evlist, cpus, NULL);63 64	err = perf_evlist__open(evlist);65	if (err) {66		fprintf(stderr, "failed to open evlist\n");67		goto out_evlist;68	}69 70	err = perf_evlist__mmap(evlist, 4);71	if (err) {72		fprintf(stderr, "failed to mmap evlist\n");73		goto out_evlist;74	}75 76	perf_evlist__enable(evlist);77	sleep(3);78	perf_evlist__disable(evlist);79 80	perf_evlist__for_each_mmap(evlist, map, false) {81		if (perf_mmap__read_init(map) < 0)82			continue;83 84		while ((event = perf_mmap__read_event(map)) != NULL) {85			int cpu, pid, tid;86			__u64 ip, period, *array;87			union u64_swap u;88 89			array = event->sample.array;90 91			ip = *array;92			array++;93 94			u.val64 = *array;95			pid = u.val32[0];96			tid = u.val32[1];97			array++;98 99			u.val64 = *array;100			cpu = u.val32[0];101			array++;102 103			period = *array;104 105			fprintf(stdout, "cpu %3d, pid %6d, tid %6d, ip %20llx, period %20llu\n",106				cpu, pid, tid, ip, period);107 108			perf_mmap__consume(map);109		}110 111		perf_mmap__read_done(map);112	}113 114out_evlist:115	perf_evlist__delete(evlist);116out_cpus:117	perf_cpu_map__put(cpus);118	return err;119}120