xref: /linux-6.15/tools/perf/tests/task-exit.c (revision 7728fa0c)
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  * perf_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 int test__task_exit(struct test *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 
58 	signal(SIGCHLD, sig_handler);
59 
60 	evlist = perf_evlist__new_default();
61 	if (evlist == NULL) {
62 		pr_debug("perf_evlist__new_default\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 	 * perf_evlist__prepare_workload we'll fill in the only thread
70 	 * we're monitoring, the one forked there.
71 	 */
72 	cpus = perf_cpu_map__dummy_new();
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_free_maps;
78 	}
79 
80 	perf_evlist__set_maps(&evlist->core, cpus, threads);
81 
82 	cpus	= NULL;
83 	threads = NULL;
84 
85 	err = perf_evlist__prepare_workload(evlist, &target, argv, false,
86 					    workload_exec_failed_signal);
87 	if (err < 0) {
88 		pr_debug("Couldn't run the workload!\n");
89 		goto out_delete_evlist;
90 	}
91 
92 	evsel = evlist__first(evlist);
93 	evsel->core.attr.task = 1;
94 #ifdef __s390x__
95 	evsel->core.attr.sample_freq = 1000000;
96 #else
97 	evsel->core.attr.sample_freq = 1;
98 #endif
99 	evsel->core.attr.inherit = 0;
100 	evsel->core.attr.watermark = 0;
101 	evsel->core.attr.wakeup_events = 1;
102 	evsel->core.attr.exclude_kernel = 1;
103 
104 	err = evlist__open(evlist);
105 	if (err < 0) {
106 		pr_debug("Couldn't open the evlist: %s\n",
107 			 str_error_r(-err, sbuf, sizeof(sbuf)));
108 		goto out_delete_evlist;
109 	}
110 
111 	if (evlist__mmap(evlist, 128) < 0) {
112 		pr_debug("failed to mmap events: %d (%s)\n", errno,
113 			 str_error_r(errno, sbuf, sizeof(sbuf)));
114 		goto out_delete_evlist;
115 	}
116 
117 	perf_evlist__start_workload(evlist);
118 
119 retry:
120 	md = &evlist->mmap[0];
121 	if (perf_mmap__read_init(md) < 0)
122 		goto out_init;
123 
124 	while ((event = perf_mmap__read_event(md)) != NULL) {
125 		if (event->header.type == PERF_RECORD_EXIT)
126 			nr_exit++;
127 
128 		perf_mmap__consume(&md->core);
129 	}
130 	perf_mmap__read_done(md);
131 
132 out_init:
133 	if (!exited || !nr_exit) {
134 		evlist__poll(evlist, -1);
135 		goto retry;
136 	}
137 
138 	if (nr_exit != 1) {
139 		pr_debug("received %d EXIT records\n", nr_exit);
140 		err = -1;
141 	}
142 
143 out_free_maps:
144 	perf_cpu_map__put(cpus);
145 	perf_thread_map__put(threads);
146 out_delete_evlist:
147 	evlist__delete(evlist);
148 	return err;
149 }
150