xref: /openbmc/linux/samples/bpf/tracex6_user.c (revision 8730046c)
1 #include <stdio.h>
2 #include <unistd.h>
3 #include <stdlib.h>
4 #include <stdbool.h>
5 #include <string.h>
6 #include <fcntl.h>
7 #include <poll.h>
8 #include <sys/ioctl.h>
9 #include <linux/perf_event.h>
10 #include <linux/bpf.h>
11 #include "libbpf.h"
12 #include "bpf_load.h"
13 #include "perf-sys.h"
14 
15 #define SAMPLE_PERIOD  0x7fffffffffffffffULL
16 
17 static void test_bpf_perf_event(void)
18 {
19 	int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
20 	int *pmu_fd = malloc(nr_cpus * sizeof(int));
21 	int status, i;
22 
23 	struct perf_event_attr attr_insn_pmu = {
24 		.freq = 0,
25 		.sample_period = SAMPLE_PERIOD,
26 		.inherit = 0,
27 		.type = PERF_TYPE_HARDWARE,
28 		.read_format = 0,
29 		.sample_type = 0,
30 		.config = 0,/* PMU: cycles */
31 	};
32 
33 	for (i = 0; i < nr_cpus; i++) {
34 		pmu_fd[i] = sys_perf_event_open(&attr_insn_pmu, -1/*pid*/, i/*cpu*/, -1/*group_fd*/, 0);
35 		if (pmu_fd[i] < 0) {
36 			printf("event syscall failed\n");
37 			goto exit;
38 		}
39 
40 		bpf_map_update_elem(map_fd[0], &i, &pmu_fd[i], BPF_ANY);
41 		ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE, 0);
42 	}
43 
44 	status = system("ls > /dev/null");
45 	if (status)
46 		goto exit;
47 	status = system("sleep 2");
48 	if (status)
49 		goto exit;
50 
51 exit:
52 	for (i = 0; i < nr_cpus; i++)
53 		close(pmu_fd[i]);
54 	close(map_fd[0]);
55 	free(pmu_fd);
56 }
57 
58 int main(int argc, char **argv)
59 {
60 	char filename[256];
61 
62 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
63 
64 	if (load_bpf_file(filename)) {
65 		printf("%s", bpf_log_buf);
66 		return 1;
67 	}
68 
69 	test_bpf_perf_event();
70 	read_trace_pipe();
71 
72 	return 0;
73 }
74