tools/perf/tests/task-exit.c

   1 #include "evlist.h"
   2 #include "evsel.h"
   3 #include "thread_map.h"
   4 #include "cpumap.h"
   5 #include "tests.h"
   6
   7 #include <errno.h>
   8 #include <signal.h>
   9
  10 static int exited;
  11 static int nr_exit;
  12
  13 static void sig_handler(int sig __maybe_unused)
  14 {
  15         exited = 1;
  16 }
  17
  18 /*
  19  * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
  20  * we asked by setting its exec_error to this handler.
  21  */
  22 static void workload_exec_failed_signal(int signo __maybe_unused,
  23                                         siginfo_t *info __maybe_unused,
  24                                         void *ucontext __maybe_unused)
  25 {
  26         exited  = 1;
  27         nr_exit = -1;
  28 }
  29
  30 /*
  31  * This test will start a workload that does nothing then it checks
  32  * if the number of exit event reported by the kernel is 1 or not
  33  * in order to check the kernel returns correct number of event.
  34  */
  35 int test__task_exit(int subtest __maybe_unused)
  36 {
  37         int err = -1;
  38         union perf_event *event;
  39         struct perf_evsel *evsel;
  40         struct perf_evlist *evlist;
  41         struct target target = {
  42                 .uid            = UINT_MAX,
  43                 .uses_mmap      = true,
  44         };
  45         const char *argv[] = { "true", NULL };
  46         char sbuf[STRERR_BUFSIZE];
  47         struct cpu_map *cpus;
  48         struct thread_map *threads;
  49
  50         signal(SIGCHLD, sig_handler);
  51
  52         evlist = perf_evlist__new_default();
  53         if (evlist == NULL) {
  54                 pr_debug("perf_evlist__new_default\n");
  55                 return -1;
  56         }
  57
  58         /*
  59          * Create maps of threads and cpus to monitor. In this case
  60          * we start with all threads and cpus (-1, -1) but then in
  61          * perf_evlist__prepare_workload we'll fill in the only thread
  62          * we're monitoring, the one forked there.
  63          */
  64         cpus = cpu_map__dummy_new();
  65         threads = thread_map__new_by_tid(-1);
  66         if (!cpus || !threads) {
  67                 err = -ENOMEM;
  68                 pr_debug("Not enough memory to create thread/cpu maps\n");
  69                 goto out_free_maps;
  70         }
  71
  72         perf_evlist__set_maps(evlist, cpus, threads);
  73
  74         cpus    = NULL;
  75         threads = NULL;
  76
  77         err = perf_evlist__prepare_workload(evlist, &target, argv, false,
  78                                             workload_exec_failed_signal);
  79         if (err < 0) {
  80                 pr_debug("Couldn't run the workload!\n");
  81                 goto out_delete_evlist;
  82         }
  83
  84         evsel = perf_evlist__first(evlist);
  85         evsel->attr.task = 1;
  86         evsel->attr.sample_freq = 0;
  87         evsel->attr.inherit = 0;
  88         evsel->attr.watermark = 0;
  89         evsel->attr.wakeup_events = 1;
  90         evsel->attr.exclude_kernel = 1;
  91
  92         err = perf_evlist__open(evlist);
  93         if (err < 0) {
  94                 pr_debug("Couldn't open the evlist: %s\n",
  95                          str_error_r(-err, sbuf, sizeof(sbuf)));
  96                 goto out_delete_evlist;
  97         }
  98
  99         if (perf_evlist__mmap(evlist, 128, true) < 0) {
 100                 pr_debug("failed to mmap events: %d (%s)\n", errno,
 101                          str_error_r(errno, sbuf, sizeof(sbuf)));
 102                 goto out_delete_evlist;
 103         }
 104
 105         perf_evlist__start_workload(evlist);
 106
 107 retry:
 108         while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
 109                 if (event->header.type == PERF_RECORD_EXIT)
 110                         nr_exit++;
 111
 112                 perf_evlist__mmap_consume(evlist, 0);
 113         }
 114
 115         if (!exited || !nr_exit) {
 116                 perf_evlist__poll(evlist, -1);
 117                 goto retry;
 118         }
 119
 120         if (nr_exit != 1) {
 121                 pr_debug("received %d EXIT records\n", nr_exit);
 122                 err = -1;
 123         }
 124
 125 out_free_maps:
 126         cpu_map__put(cpus);
 127         thread_map__put(threads);
 128 out_delete_evlist:
 129         perf_evlist__delete(evlist);
 130         return err;
 131 }