xref: /openbmc/linux/tools/perf/tests/task-exit.c (revision bc05aa6e)
1 // SPDX-License-Identifier: GPL-2.0
2 #include "evlist.h"
3 #include "evsel.h"
4 #include "thread_map.h"
5 #include "cpumap.h"
6 #include "tests.h"
7 
8 #include <errno.h>
9 #include <signal.h>
10 
11 static int exited;
12 static int nr_exit;
13 
14 static void sig_handler(int sig __maybe_unused)
15 {
16 	exited = 1;
17 }
18 
19 /*
20  * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
21  * we asked by setting its exec_error to this handler.
22  */
23 static void workload_exec_failed_signal(int signo __maybe_unused,
24 					siginfo_t *info __maybe_unused,
25 					void *ucontext __maybe_unused)
26 {
27 	exited	= 1;
28 	nr_exit = -1;
29 }
30 
31 /*
32  * This test will start a workload that does nothing then it checks
33  * if the number of exit event reported by the kernel is 1 or not
34  * in order to check the kernel returns correct number of event.
35  */
36 int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused)
37 {
38 	int err = -1;
39 	union perf_event *event;
40 	struct perf_evsel *evsel;
41 	struct perf_evlist *evlist;
42 	struct target target = {
43 		.uid		= UINT_MAX,
44 		.uses_mmap	= true,
45 	};
46 	const char *argv[] = { "true", NULL };
47 	char sbuf[STRERR_BUFSIZE];
48 	struct cpu_map *cpus;
49 	struct thread_map *threads;
50 
51 	signal(SIGCHLD, sig_handler);
52 
53 	evlist = perf_evlist__new_default();
54 	if (evlist == NULL) {
55 		pr_debug("perf_evlist__new_default\n");
56 		return -1;
57 	}
58 
59 	/*
60 	 * Create maps of threads and cpus to monitor. In this case
61 	 * we start with all threads and cpus (-1, -1) but then in
62 	 * perf_evlist__prepare_workload we'll fill in the only thread
63 	 * we're monitoring, the one forked there.
64 	 */
65 	cpus = cpu_map__dummy_new();
66 	threads = thread_map__new_by_tid(-1);
67 	if (!cpus || !threads) {
68 		err = -ENOMEM;
69 		pr_debug("Not enough memory to create thread/cpu maps\n");
70 		goto out_free_maps;
71 	}
72 
73 	perf_evlist__set_maps(evlist, cpus, threads);
74 
75 	cpus	= NULL;
76 	threads = NULL;
77 
78 	err = perf_evlist__prepare_workload(evlist, &target, argv, false,
79 					    workload_exec_failed_signal);
80 	if (err < 0) {
81 		pr_debug("Couldn't run the workload!\n");
82 		goto out_delete_evlist;
83 	}
84 
85 	evsel = perf_evlist__first(evlist);
86 	evsel->attr.task = 1;
87 #ifdef __s390x__
88 	evsel->attr.sample_freq = 1000000;
89 #else
90 	evsel->attr.sample_freq = 1;
91 #endif
92 	evsel->attr.inherit = 0;
93 	evsel->attr.watermark = 0;
94 	evsel->attr.wakeup_events = 1;
95 	evsel->attr.exclude_kernel = 1;
96 
97 	err = perf_evlist__open(evlist);
98 	if (err < 0) {
99 		pr_debug("Couldn't open the evlist: %s\n",
100 			 str_error_r(-err, sbuf, sizeof(sbuf)));
101 		goto out_delete_evlist;
102 	}
103 
104 	if (perf_evlist__mmap(evlist, 128) < 0) {
105 		pr_debug("failed to mmap events: %d (%s)\n", errno,
106 			 str_error_r(errno, sbuf, sizeof(sbuf)));
107 		goto out_delete_evlist;
108 	}
109 
110 	perf_evlist__start_workload(evlist);
111 
112 retry:
113 	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
114 		if (event->header.type == PERF_RECORD_EXIT)
115 			nr_exit++;
116 
117 		perf_evlist__mmap_consume(evlist, 0);
118 	}
119 
120 	if (!exited || !nr_exit) {
121 		perf_evlist__poll(evlist, -1);
122 		goto retry;
123 	}
124 
125 	if (nr_exit != 1) {
126 		pr_debug("received %d EXIT records\n", nr_exit);
127 		err = -1;
128 	}
129 
130 out_free_maps:
131 	cpu_map__put(cpus);
132 	thread_map__put(threads);
133 out_delete_evlist:
134 	perf_evlist__delete(evlist);
135 	return err;
136 }
137