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
17static int exited;
18static int nr_exit;
19
20static 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 */
29static 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 */
42static 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__new_any_cpu();
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
117retry:
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
130out_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
148out_delete_evlist:
149 perf_cpu_map__put(cpus);
150 perf_thread_map__put(threads);
151 evlist__delete(evlist);
152 return err;
153}
154
155DEFINE_SUITE("Number of exit events of a simple workload", task_exit);
156

source code of linux/tools/perf/tests/task-exit.c