Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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 .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 int retry_count = 0;
57
58 signal(SIGCHLD, sig_handler);
59
60 evlist = evlist__new_dummy();
61 if (evlist == NULL) {
62 pr_debug("evlist__new_dummy\n");
63 return -1;
64 }
65
66 /*
67 * Create maps of threads and cpus to monitor. In this case
68 * we start with all threads and cpus (-1, -1) but then in
69 * evlist__prepare_workload we'll fill in the only thread
70 * we're monitoring, the one forked there.
71 */
72 cpus = perf_cpu_map__new_any_cpu();
73 threads = thread_map__new_by_tid(-1);
74 if (!cpus || !threads) {
75 err = -ENOMEM;
76 pr_debug("Not enough memory to create thread/cpu maps\n");
77 goto out_delete_evlist;
78 }
79
80 perf_evlist__set_maps(&evlist->core, cpus, threads);
81
82 err = evlist__prepare_workload(evlist, &target, argv, false, workload_exec_failed_signal);
83 if (err < 0) {
84 pr_debug("Couldn't run the workload!\n");
85 goto out_delete_evlist;
86 }
87
88 evsel = evlist__first(evlist);
89 evsel->core.attr.task = 1;
90#ifdef __s390x__
91 evsel->core.attr.sample_freq = 1000000;
92#else
93 evsel->core.attr.sample_freq = 1;
94#endif
95 evsel->core.attr.inherit = 0;
96 evsel->core.attr.watermark = 0;
97 evsel->core.attr.wakeup_events = 1;
98 evsel->core.attr.exclude_kernel = 1;
99
100 err = evlist__open(evlist);
101 if (err < 0) {
102 pr_debug("Couldn't open the evlist: %s\n",
103 str_error_r(-err, sbuf, sizeof(sbuf)));
104 goto out_delete_evlist;
105 }
106
107 if (evlist__mmap(evlist, 128) < 0) {
108 pr_debug("failed to mmap events: %d (%s)\n", errno,
109 str_error_r(errno, sbuf, sizeof(sbuf)));
110 err = -1;
111 goto out_delete_evlist;
112 }
113
114 evlist__start_workload(evlist);
115
116retry:
117 md = &evlist->mmap[0];
118 if (perf_mmap__read_init(&md->core) < 0)
119 goto out_init;
120
121 while ((event = perf_mmap__read_event(&md->core)) != NULL) {
122 if (event->header.type == PERF_RECORD_EXIT)
123 nr_exit++;
124
125 perf_mmap__consume(&md->core);
126 }
127 perf_mmap__read_done(&md->core);
128
129out_init:
130 if (!exited || !nr_exit) {
131 evlist__poll(evlist, -1);
132
133 if (retry_count++ > 1000) {
134 pr_debug("Failed after retrying 1000 times\n");
135 err = -1;
136 goto out_delete_evlist;
137 }
138
139 goto retry;
140 }
141
142 if (nr_exit != 1) {
143 pr_debug("received %d EXIT records\n", nr_exit);
144 err = -1;
145 }
146
147out_delete_evlist:
148 perf_cpu_map__put(cpus);
149 perf_thread_map__put(threads);
150 evlist__delete(evlist);
151 return err;
152}
153
154struct test_case tests__task_exit[] = {
155 TEST_CASE_EXCLUSIVE("Number of exit events of a simple workload", task_exit),
156 { .name = NULL, }
157};
158struct test_suite suite__task_exit = {
159 .desc = "Number of exit events of a simple workload",
160 .test_cases = tests__task_exit,
161};