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 
12 static int libperf_print(enum libperf_print_level level,
13                          const char *fmt, va_list ap)
14 {
15 	return vfprintf(stderr, fmt, ap);
16 }
17 
18 union u64_swap {
19 	__u64 val64;
20 	__u32 val32[2];
21 };
22 
23 int 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(NULL);
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 
114 out_evlist:
115 	perf_evlist__delete(evlist);
116 out_cpus:
117 	perf_cpu_map__put(cpus);
118 	return err;
119 }
120