1 /* This program is free software; you can redistribute it and/or
2 * modify it under the terms of version 2 of the GNU General Public
3 * License as published by the Free Software Foundation.
12 #include <linux/perf_event.h>
13 #include <linux/bpf.h>
16 #include <sys/syscall.h>
17 #include <sys/ioctl.h>
24 #include "trace_helpers.h"
28 static __u64 time_get_ns(void)
32 clock_gettime(CLOCK_MONOTONIC, &ts);
33 return ts.tv_sec * 1000000000ull + ts.tv_nsec;
36 static __u64 start_time;
38 #define MAX_CNT 100000ll
40 static int print_bpf_output(void *data, int size)
48 if (e->cookie != 0x12345678) {
49 printf("BUG pid %llx cookie %llx sized %d\n",
50 e->pid, e->cookie, size);
51 return LIBBPF_PERF_EVENT_ERROR;
57 printf("recv %lld events per sec\n",
58 MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
59 return LIBBPF_PERF_EVENT_DONE;
62 return LIBBPF_PERF_EVENT_CONT;
65 static void test_bpf_perf_event(void)
67 struct perf_event_attr attr = {
68 .sample_type = PERF_SAMPLE_RAW,
69 .type = PERF_TYPE_SOFTWARE,
70 .config = PERF_COUNT_SW_BPF_OUTPUT,
74 pmu_fd = sys_perf_event_open(&attr, -1/*pid*/, 0/*cpu*/, -1/*group_fd*/, 0);
77 assert(bpf_map_update_elem(map_fd[0], &key, &pmu_fd, BPF_ANY) == 0);
78 ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
81 int main(int argc, char **argv)
87 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
89 if (load_bpf_file(filename)) {
90 printf("%s", bpf_log_buf);
94 test_bpf_perf_event();
96 if (perf_event_mmap(pmu_fd) < 0)
99 f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r");
102 start_time = time_get_ns();
103 ret = perf_event_poller(pmu_fd, print_bpf_output);