1 // SPDX-License-Identifier: GPL-2.0-only
9 #include <linux/perf_event.h>
10 #include <linux/bpf.h>
13 #include <sys/syscall.h>
14 #include <sys/ioctl.h>
21 #include "trace_helpers.h"
25 static __u64 time_get_ns(void)
29 clock_gettime(CLOCK_MONOTONIC, &ts);
30 return ts.tv_sec * 1000000000ull + ts.tv_nsec;
33 static __u64 start_time;
35 #define MAX_CNT 100000ll
37 static int print_bpf_output(void *data, int size)
45 if (e->cookie != 0x12345678) {
46 printf("BUG pid %llx cookie %llx sized %d\n",
47 e->pid, e->cookie, size);
48 return LIBBPF_PERF_EVENT_ERROR;
54 printf("recv %lld events per sec\n",
55 MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
56 return LIBBPF_PERF_EVENT_DONE;
59 return LIBBPF_PERF_EVENT_CONT;
62 static void test_bpf_perf_event(void)
64 struct perf_event_attr attr = {
65 .sample_type = PERF_SAMPLE_RAW,
66 .type = PERF_TYPE_SOFTWARE,
67 .config = PERF_COUNT_SW_BPF_OUTPUT,
71 pmu_fd = sys_perf_event_open(&attr, -1/*pid*/, 0/*cpu*/, -1/*group_fd*/, 0);
74 assert(bpf_map_update_elem(map_fd[0], &key, &pmu_fd, BPF_ANY) == 0);
75 ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
78 int main(int argc, char **argv)
84 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
86 if (load_bpf_file(filename)) {
87 printf("%s", bpf_log_buf);
91 test_bpf_perf_event();
93 if (perf_event_mmap(pmu_fd) < 0)
96 f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r");
99 start_time = time_get_ns();
100 ret = perf_event_poller(pmu_fd, print_bpf_output);