tools/perf/tests/task-exit.c

   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 }