xref: /openbmc/linux/tools/perf/tests/task-exit.c (revision e553d2a5)
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 "cpumap.h"
8 #include "tests.h"
9 
10 #include <errno.h>
11 #include <signal.h>
12 #include <linux/string.h>
13 #include <perf/evlist.h>
14 
15 static int exited;
16 static int nr_exit;
17 
18 static void sig_handler(int sig __maybe_unused)
19 {
20 	exited = 1;
21 }
22 
23 /*
24  * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
25  * we asked by setting its exec_error to this handler.
26  */
27 static void workload_exec_failed_signal(int signo __maybe_unused,
28 					siginfo_t *info __maybe_unused,
29 					void *ucontext __maybe_unused)
30 {
31 	exited	= 1;
32 	nr_exit = -1;
33 }
34 
35 /*
36  * This test will start a workload that does nothing then it checks
37  * if the number of exit event reported by the kernel is 1 or not
38  * in order to check the kernel returns correct number of event.
39  */
40 int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused)
41 {
42 	int err = -1;
43 	union perf_event *event;
44 	struct evsel *evsel;
45 	struct evlist *evlist;
46 	struct target target = {
47 		.uid		= UINT_MAX,
48 		.uses_mmap	= true,
49 	};
50 	const char *argv[] = { "true", NULL };
51 	char sbuf[STRERR_BUFSIZE];
52 	struct perf_cpu_map *cpus;
53 	struct perf_thread_map *threads;
54 	struct perf_mmap *md;
55 
56 	signal(SIGCHLD, sig_handler);
57 
58 	evlist = perf_evlist__new_default();
59 	if (evlist == NULL) {
60 		pr_debug("perf_evlist__new_default\n");
61 		return -1;
62 	}
63 
64 	/*
65 	 * Create maps of threads and cpus to monitor. In this case
66 	 * we start with all threads and cpus (-1, -1) but then in
67 	 * perf_evlist__prepare_workload we'll fill in the only thread
68 	 * we're monitoring, the one forked there.
69 	 */
70 	cpus = perf_cpu_map__dummy_new();
71 	threads = thread_map__new_by_tid(-1);
72 	if (!cpus || !threads) {
73 		err = -ENOMEM;
74 		pr_debug("Not enough memory to create thread/cpu maps\n");
75 		goto out_free_maps;
76 	}
77 
78 	perf_evlist__set_maps(&evlist->core, cpus, threads);
79 
80 	cpus	= NULL;
81 	threads = NULL;
82 
83 	err = perf_evlist__prepare_workload(evlist, &target, argv, false,
84 					    workload_exec_failed_signal);
85 	if (err < 0) {
86 		pr_debug("Couldn't run the workload!\n");
87 		goto out_delete_evlist;
88 	}
89 
90 	evsel = perf_evlist__first(evlist);
91 	evsel->core.attr.task = 1;
92 #ifdef __s390x__
93 	evsel->core.attr.sample_freq = 1000000;
94 #else
95 	evsel->core.attr.sample_freq = 1;
96 #endif
97 	evsel->core.attr.inherit = 0;
98 	evsel->core.attr.watermark = 0;
99 	evsel->core.attr.wakeup_events = 1;
100 	evsel->core.attr.exclude_kernel = 1;
101 
102 	err = evlist__open(evlist);
103 	if (err < 0) {
104 		pr_debug("Couldn't open the evlist: %s\n",
105 			 str_error_r(-err, sbuf, sizeof(sbuf)));
106 		goto out_delete_evlist;
107 	}
108 
109 	if (perf_evlist__mmap(evlist, 128) < 0) {
110 		pr_debug("failed to mmap events: %d (%s)\n", errno,
111 			 str_error_r(errno, sbuf, sizeof(sbuf)));
112 		goto out_delete_evlist;
113 	}
114 
115 	perf_evlist__start_workload(evlist);
116 
117 retry:
118 	md = &evlist->mmap[0];
119 	if (perf_mmap__read_init(md) < 0)
120 		goto out_init;
121 
122 	while ((event = perf_mmap__read_event(md)) != NULL) {
123 		if (event->header.type == PERF_RECORD_EXIT)
124 			nr_exit++;
125 
126 		perf_mmap__consume(md);
127 	}
128 	perf_mmap__read_done(md);
129 
130 out_init:
131 	if (!exited || !nr_exit) {
132 		perf_evlist__poll(evlist, -1);
133 		goto retry;
134 	}
135 
136 	if (nr_exit != 1) {
137 		pr_debug("received %d EXIT records\n", nr_exit);
138 		err = -1;
139 	}
140 
141 out_free_maps:
142 	perf_cpu_map__put(cpus);
143 	perf_thread_map__put(threads);
144 out_delete_evlist:
145 	evlist__delete(evlist);
146 	return err;
147 }
148