xref: /openbmc/linux/tools/perf/tests/task-exit.c (revision b9df3997)
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 
16 static int exited;
17 static int nr_exit;
18 
19 static void sig_handler(int sig __maybe_unused)
20 {
21 	exited = 1;
22 }
23 
24 /*
25  * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
26  * we asked by setting its exec_error to this handler.
27  */
28 static void workload_exec_failed_signal(int signo __maybe_unused,
29 					siginfo_t *info __maybe_unused,
30 					void *ucontext __maybe_unused)
31 {
32 	exited	= 1;
33 	nr_exit = -1;
34 }
35 
36 /*
37  * This test will start a workload that does nothing then it checks
38  * if the number of exit event reported by the kernel is 1 or not
39  * in order to check the kernel returns correct number of event.
40  */
41 int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused)
42 {
43 	int err = -1;
44 	union perf_event *event;
45 	struct evsel *evsel;
46 	struct evlist *evlist;
47 	struct target target = {
48 		.uid		= UINT_MAX,
49 		.uses_mmap	= true,
50 	};
51 	const char *argv[] = { "true", NULL };
52 	char sbuf[STRERR_BUFSIZE];
53 	struct perf_cpu_map *cpus;
54 	struct perf_thread_map *threads;
55 	struct mmap *md;
56 
57 	signal(SIGCHLD, sig_handler);
58 
59 	evlist = perf_evlist__new_default();
60 	if (evlist == NULL) {
61 		pr_debug("perf_evlist__new_default\n");
62 		return -1;
63 	}
64 
65 	/*
66 	 * Create maps of threads and cpus to monitor. In this case
67 	 * we start with all threads and cpus (-1, -1) but then in
68 	 * perf_evlist__prepare_workload we'll fill in the only thread
69 	 * we're monitoring, the one forked there.
70 	 */
71 	cpus = perf_cpu_map__dummy_new();
72 	threads = thread_map__new_by_tid(-1);
73 	if (!cpus || !threads) {
74 		err = -ENOMEM;
75 		pr_debug("Not enough memory to create thread/cpu maps\n");
76 		goto out_free_maps;
77 	}
78 
79 	perf_evlist__set_maps(&evlist->core, cpus, threads);
80 
81 	cpus	= NULL;
82 	threads = NULL;
83 
84 	err = perf_evlist__prepare_workload(evlist, &target, argv, false,
85 					    workload_exec_failed_signal);
86 	if (err < 0) {
87 		pr_debug("Couldn't run the workload!\n");
88 		goto out_delete_evlist;
89 	}
90 
91 	evsel = evlist__first(evlist);
92 	evsel->core.attr.task = 1;
93 #ifdef __s390x__
94 	evsel->core.attr.sample_freq = 1000000;
95 #else
96 	evsel->core.attr.sample_freq = 1;
97 #endif
98 	evsel->core.attr.inherit = 0;
99 	evsel->core.attr.watermark = 0;
100 	evsel->core.attr.wakeup_events = 1;
101 	evsel->core.attr.exclude_kernel = 1;
102 
103 	err = evlist__open(evlist);
104 	if (err < 0) {
105 		pr_debug("Couldn't open the evlist: %s\n",
106 			 str_error_r(-err, sbuf, sizeof(sbuf)));
107 		goto out_delete_evlist;
108 	}
109 
110 	if (evlist__mmap(evlist, 128) < 0) {
111 		pr_debug("failed to mmap events: %d (%s)\n", errno,
112 			 str_error_r(errno, sbuf, sizeof(sbuf)));
113 		goto out_delete_evlist;
114 	}
115 
116 	perf_evlist__start_workload(evlist);
117 
118 retry:
119 	md = &evlist->mmap[0];
120 	if (perf_mmap__read_init(md) < 0)
121 		goto out_init;
122 
123 	while ((event = perf_mmap__read_event(md)) != NULL) {
124 		if (event->header.type == PERF_RECORD_EXIT)
125 			nr_exit++;
126 
127 		perf_mmap__consume(md);
128 	}
129 	perf_mmap__read_done(md);
130 
131 out_init:
132 	if (!exited || !nr_exit) {
133 		evlist__poll(evlist, -1);
134 		goto retry;
135 	}
136 
137 	if (nr_exit != 1) {
138 		pr_debug("received %d EXIT records\n", nr_exit);
139 		err = -1;
140 	}
141 
142 out_free_maps:
143 	perf_cpu_map__put(cpus);
144 	perf_thread_map__put(threads);
145 out_delete_evlist:
146 	evlist__delete(evlist);
147 	return err;
148 }
149