xref: /openbmc/linux/tools/perf/tests/task-exit.c (revision 86e281fc)
1 // SPDX-License-Identifier: GPL-2.0
2 #include "debug.h"
3 #include "evlist.h"
4 #include "evsel.h"
5 #include "target.h"
6 #include "thread_map.h"
7 #include "tests.h"
8 #include "util/mmap.h"
9 
10 #include <errno.h>
11 #include <signal.h>
12 #include <linux/string.h>
13 #include <perf/cpumap.h>
14 #include <perf/evlist.h>
15 #include <perf/mmap.h>
16 
17 static int exited;
18 static int nr_exit;
19 
20 static void sig_handler(int sig __maybe_unused)
21 {
22 	exited = 1;
23 }
24 
25 /*
26  * evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
27  * we asked by setting its exec_error to this handler.
28  */
29 static void workload_exec_failed_signal(int signo __maybe_unused,
30 					siginfo_t *info __maybe_unused,
31 					void *ucontext __maybe_unused)
32 {
33 	exited	= 1;
34 	nr_exit = -1;
35 }
36 
37 /*
38  * This test will start a workload that does nothing then it checks
39  * if the number of exit event reported by the kernel is 1 or not
40  * in order to check the kernel returns correct number of event.
41  */
42 static int test__task_exit(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
43 {
44 	int err = -1;
45 	union perf_event *event;
46 	struct evsel *evsel;
47 	struct evlist *evlist;
48 	struct target target = {
49 		.uid		= UINT_MAX,
50 		.uses_mmap	= true,
51 	};
52 	const char *argv[] = { "true", NULL };
53 	char sbuf[STRERR_BUFSIZE];
54 	struct perf_cpu_map *cpus;
55 	struct perf_thread_map *threads;
56 	struct mmap *md;
57 	int retry_count = 0;
58 
59 	signal(SIGCHLD, sig_handler);
60 
61 	evlist = evlist__new_dummy();
62 	if (evlist == NULL) {
63 		pr_debug("evlist__new_dummy\n");
64 		return -1;
65 	}
66 
67 	/*
68 	 * Create maps of threads and cpus to monitor. In this case
69 	 * we start with all threads and cpus (-1, -1) but then in
70 	 * evlist__prepare_workload we'll fill in the only thread
71 	 * we're monitoring, the one forked there.
72 	 */
73 	cpus = perf_cpu_map__dummy_new();
74 	threads = thread_map__new_by_tid(-1);
75 	if (!cpus || !threads) {
76 		err = -ENOMEM;
77 		pr_debug("Not enough memory to create thread/cpu maps\n");
78 		goto out_delete_evlist;
79 	}
80 
81 	perf_evlist__set_maps(&evlist->core, cpus, threads);
82 
83 	err = evlist__prepare_workload(evlist, &target, argv, false, workload_exec_failed_signal);
84 	if (err < 0) {
85 		pr_debug("Couldn't run the workload!\n");
86 		goto out_delete_evlist;
87 	}
88 
89 	evsel = evlist__first(evlist);
90 	evsel->core.attr.task = 1;
91 #ifdef __s390x__
92 	evsel->core.attr.sample_freq = 1000000;
93 #else
94 	evsel->core.attr.sample_freq = 1;
95 #endif
96 	evsel->core.attr.inherit = 0;
97 	evsel->core.attr.watermark = 0;
98 	evsel->core.attr.wakeup_events = 1;
99 	evsel->core.attr.exclude_kernel = 1;
100 
101 	err = evlist__open(evlist);
102 	if (err < 0) {
103 		pr_debug("Couldn't open the evlist: %s\n",
104 			 str_error_r(-err, sbuf, sizeof(sbuf)));
105 		goto out_delete_evlist;
106 	}
107 
108 	if (evlist__mmap(evlist, 128) < 0) {
109 		pr_debug("failed to mmap events: %d (%s)\n", errno,
110 			 str_error_r(errno, sbuf, sizeof(sbuf)));
111 		err = -1;
112 		goto out_delete_evlist;
113 	}
114 
115 	evlist__start_workload(evlist);
116 
117 retry:
118 	md = &evlist->mmap[0];
119 	if (perf_mmap__read_init(&md->core) < 0)
120 		goto out_init;
121 
122 	while ((event = perf_mmap__read_event(&md->core)) != NULL) {
123 		if (event->header.type == PERF_RECORD_EXIT)
124 			nr_exit++;
125 
126 		perf_mmap__consume(&md->core);
127 	}
128 	perf_mmap__read_done(&md->core);
129 
130 out_init:
131 	if (!exited || !nr_exit) {
132 		evlist__poll(evlist, -1);
133 
134 		if (retry_count++ > 1000) {
135 			pr_debug("Failed after retrying 1000 times\n");
136 			err = -1;
137 			goto out_delete_evlist;
138 		}
139 
140 		goto retry;
141 	}
142 
143 	if (nr_exit != 1) {
144 		pr_debug("received %d EXIT records\n", nr_exit);
145 		err = -1;
146 	}
147 
148 out_delete_evlist:
149 	perf_cpu_map__put(cpus);
150 	perf_thread_map__put(threads);
151 	evlist__delete(evlist);
152 	return err;
153 }
154 
155 DEFINE_SUITE("Number of exit events of a simple workload", task_exit);
156