xref: /linux/tools/perf/tests/task-exit.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 #include "evlist.h"
2 #include "evsel.h"
3 #include "thread_map.h"
4 #include "cpumap.h"
5 #include "tests.h"
6 
7 #include <signal.h>
8 
9 static int exited;
10 static int nr_exit;
11 
12 static void sig_handler(int sig __maybe_unused)
13 {
14 	exited = 1;
15 }
16 
17 /*
18  * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
19  * we asked by setting its exec_error to this handler.
20  */
21 static void workload_exec_failed_signal(int signo __maybe_unused,
22 					siginfo_t *info __maybe_unused,
23 					void *ucontext __maybe_unused)
24 {
25 	exited	= 1;
26 	nr_exit = -1;
27 }
28 
29 /*
30  * This test will start a workload that does nothing then it checks
31  * if the number of exit event reported by the kernel is 1 or not
32  * in order to check the kernel returns correct number of event.
33  */
34 int test__task_exit(void)
35 {
36 	int err = -1;
37 	union perf_event *event;
38 	struct perf_evsel *evsel;
39 	struct perf_evlist *evlist;
40 	struct target target = {
41 		.uid		= UINT_MAX,
42 		.uses_mmap	= true,
43 	};
44 	const char *argv[] = { "true", NULL };
45 	char sbuf[STRERR_BUFSIZE];
46 	struct cpu_map *cpus;
47 	struct thread_map *threads;
48 
49 	signal(SIGCHLD, sig_handler);
50 
51 	evlist = perf_evlist__new_default();
52 	if (evlist == NULL) {
53 		pr_debug("perf_evlist__new_default\n");
54 		return -1;
55 	}
56 
57 	/*
58 	 * Create maps of threads and cpus to monitor. In this case
59 	 * we start with all threads and cpus (-1, -1) but then in
60 	 * perf_evlist__prepare_workload we'll fill in the only thread
61 	 * we're monitoring, the one forked there.
62 	 */
63 	cpus = cpu_map__dummy_new();
64 	threads = thread_map__new_by_tid(-1);
65 	if (!cpus || !threads) {
66 		err = -ENOMEM;
67 		pr_debug("Not enough memory to create thread/cpu maps\n");
68 		goto out_free_maps;
69 	}
70 
71 	perf_evlist__set_maps(evlist, cpus, threads);
72 
73 	cpus	= NULL;
74 	threads = NULL;
75 
76 	err = perf_evlist__prepare_workload(evlist, &target, argv, false,
77 					    workload_exec_failed_signal);
78 	if (err < 0) {
79 		pr_debug("Couldn't run the workload!\n");
80 		goto out_delete_evlist;
81 	}
82 
83 	evsel = perf_evlist__first(evlist);
84 	evsel->attr.task = 1;
85 	evsel->attr.sample_freq = 0;
86 	evsel->attr.inherit = 0;
87 	evsel->attr.watermark = 0;
88 	evsel->attr.wakeup_events = 1;
89 	evsel->attr.exclude_kernel = 1;
90 
91 	err = perf_evlist__open(evlist);
92 	if (err < 0) {
93 		pr_debug("Couldn't open the evlist: %s\n",
94 			 strerror_r(-err, sbuf, sizeof(sbuf)));
95 		goto out_delete_evlist;
96 	}
97 
98 	if (perf_evlist__mmap(evlist, 128, true) < 0) {
99 		pr_debug("failed to mmap events: %d (%s)\n", errno,
100 			 strerror_r(errno, sbuf, sizeof(sbuf)));
101 		goto out_delete_evlist;
102 	}
103 
104 	perf_evlist__start_workload(evlist);
105 
106 retry:
107 	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
108 		if (event->header.type == PERF_RECORD_EXIT)
109 			nr_exit++;
110 
111 		perf_evlist__mmap_consume(evlist, 0);
112 	}
113 
114 	if (!exited || !nr_exit) {
115 		perf_evlist__poll(evlist, -1);
116 		goto retry;
117 	}
118 
119 	if (nr_exit != 1) {
120 		pr_debug("received %d EXIT records\n", nr_exit);
121 		err = -1;
122 	}
123 
124 out_free_maps:
125 	cpu_map__put(cpus);
126 	thread_map__put(threads);
127 out_delete_evlist:
128 	perf_evlist__delete(evlist);
129 	return err;
130 }
131