xref: /linux/tools/perf/tests/task-exit.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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 
47 	signal(SIGCHLD, sig_handler);
48 
49 	evlist = perf_evlist__new_default();
50 	if (evlist == NULL) {
51 		pr_debug("perf_evlist__new_default\n");
52 		return -1;
53 	}
54 
55 	/*
56 	 * Create maps of threads and cpus to monitor. In this case
57 	 * we start with all threads and cpus (-1, -1) but then in
58 	 * perf_evlist__prepare_workload we'll fill in the only thread
59 	 * we're monitoring, the one forked there.
60 	 */
61 	evlist->cpus = cpu_map__dummy_new();
62 	evlist->threads = thread_map__new_by_tid(-1);
63 	if (!evlist->cpus || !evlist->threads) {
64 		err = -ENOMEM;
65 		pr_debug("Not enough memory to create thread/cpu maps\n");
66 		goto out_delete_evlist;
67 	}
68 
69 	err = perf_evlist__prepare_workload(evlist, &target, argv, false,
70 					    workload_exec_failed_signal);
71 	if (err < 0) {
72 		pr_debug("Couldn't run the workload!\n");
73 		goto out_delete_evlist;
74 	}
75 
76 	evsel = perf_evlist__first(evlist);
77 	evsel->attr.task = 1;
78 	evsel->attr.sample_freq = 0;
79 	evsel->attr.inherit = 0;
80 	evsel->attr.watermark = 0;
81 	evsel->attr.wakeup_events = 1;
82 	evsel->attr.exclude_kernel = 1;
83 
84 	err = perf_evlist__open(evlist);
85 	if (err < 0) {
86 		pr_debug("Couldn't open the evlist: %s\n",
87 			 strerror_r(-err, sbuf, sizeof(sbuf)));
88 		goto out_delete_evlist;
89 	}
90 
91 	if (perf_evlist__mmap(evlist, 128, true) < 0) {
92 		pr_debug("failed to mmap events: %d (%s)\n", errno,
93 			 strerror_r(errno, sbuf, sizeof(sbuf)));
94 		goto out_delete_evlist;
95 	}
96 
97 	perf_evlist__start_workload(evlist);
98 
99 retry:
100 	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
101 		if (event->header.type == PERF_RECORD_EXIT)
102 			nr_exit++;
103 
104 		perf_evlist__mmap_consume(evlist, 0);
105 	}
106 
107 	if (!exited || !nr_exit) {
108 		perf_evlist__poll(evlist, -1);
109 		goto retry;
110 	}
111 
112 	if (nr_exit != 1) {
113 		pr_debug("received %d EXIT records\n", nr_exit);
114 		err = -1;
115 	}
116 
117 out_delete_evlist:
118 	perf_evlist__delete(evlist);
119 	return err;
120 }
121