tools/perf/tests/keep-tracking.c

   1 #include <sys/types.h>
   2 #include <unistd.h>
   3 #include <sys/prctl.h>
   4
   5 #include "parse-events.h"
   6 #include "evlist.h"
   7 #include "evsel.h"
   8 #include "thread_map.h"
   9 #include "cpumap.h"
  10 #include "tests.h"
  11
  12 #define CHECK__(x) {                            \
  13         while ((x) < 0) {                       \
  14                 pr_debug(#x " failed!\n");      \
  15                 goto out_err;                   \
  16         }                                       \
  17 }
  18
  19 #define CHECK_NOT_NULL__(x) {                   \
  20         while ((x) == NULL) {                   \
  21                 pr_debug(#x " failed!\n");      \
  22                 goto out_err;                   \
  23         }                                       \
  24 }
  25
  26 static int find_comm(struct perf_evlist *evlist, const char *comm)
  27 {
  28         union perf_event *event;
  29         int i, found;
  30
  31         found = 0;
  32         for (i = 0; i < evlist->nr_mmaps; i++) {
  33                 while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
  34                         if (event->header.type == PERF_RECORD_COMM &&
  35                             (pid_t)event->comm.pid == getpid() &&
  36                             (pid_t)event->comm.tid == getpid() &&
  37                             strcmp(event->comm.comm, comm) == 0)
  38                                 found += 1;
  39                 }
  40         }
  41         return found;
  42 }
  43
  44 /**
  45  * test__keep_tracking - test using a dummy software event to keep tracking.
  46  *
  47  * This function implements a test that checks that tracking events continue
  48  * when an event is disabled but a dummy software event is not disabled.  If the
  49  * test passes %0 is returned, otherwise %-1 is returned.
  50  */
  51 int test__keep_tracking(void)
  52 {
  53         struct perf_record_opts opts = {
  54                 .mmap_pages          = UINT_MAX,
  55                 .user_freq           = UINT_MAX,
  56                 .user_interval       = ULLONG_MAX,
  57                 .freq                = 4000,
  58                 .target              = {
  59                         .uses_mmap   = true,
  60                 },
  61         };
  62         struct thread_map *threads = NULL;
  63         struct cpu_map *cpus = NULL;
  64         struct perf_evlist *evlist = NULL;
  65         struct perf_evsel *evsel = NULL;
  66         int found, err = -1;
  67         const char *comm;
  68
  69         threads = thread_map__new(-1, getpid(), UINT_MAX);
  70         CHECK_NOT_NULL__(threads);
  71
  72         cpus = cpu_map__new(NULL);
  73         CHECK_NOT_NULL__(cpus);
  74
  75         evlist = perf_evlist__new();
  76         CHECK_NOT_NULL__(evlist);
  77
  78         perf_evlist__set_maps(evlist, cpus, threads);
  79
  80         CHECK__(parse_events(evlist, "dummy:u"));
  81         CHECK__(parse_events(evlist, "cycles:u"));
  82
  83         perf_evlist__config(evlist, &opts);
  84
  85         evsel = perf_evlist__first(evlist);
  86
  87         evsel->attr.comm = 1;
  88         evsel->attr.disabled = 1;
  89         evsel->attr.enable_on_exec = 0;
  90
  91         if (perf_evlist__open(evlist) < 0) {
  92                 fprintf(stderr, " (not supported)");
  93                 err = 0;
  94                 goto out_err;
  95         }
  96
  97         CHECK__(perf_evlist__mmap(evlist, UINT_MAX, false));
  98
  99         /*
 100          * First, test that a 'comm' event can be found when the event is
 101          * enabled.
 102          */
 103
 104         perf_evlist__enable(evlist);
 105
 106         comm = "Test COMM 1";
 107         CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0));
 108
 109         perf_evlist__disable(evlist);
 110
 111         found = find_comm(evlist, comm);
 112         if (found != 1) {
 113                 pr_debug("First time, failed to find tracking event.\n");
 114                 goto out_err;
 115         }
 116
 117         /*
 118          * Secondly, test that a 'comm' event can be found when the event is
 119          * disabled with the dummy event still enabled.
 120          */
 121
 122         perf_evlist__enable(evlist);
 123
 124         evsel = perf_evlist__last(evlist);
 125
 126         CHECK__(perf_evlist__disable_event(evlist, evsel));
 127
 128         comm = "Test COMM 2";
 129         CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0));
 130
 131         perf_evlist__disable(evlist);
 132
 133         found = find_comm(evlist, comm);
 134         if (found != 1) {
 135                 pr_debug("Seconf time, failed to find tracking event.\n");
 136                 goto out_err;
 137         }
 138
 139         err = 0;
 140
 141 out_err:
 142         if (evlist) {
 143                 perf_evlist__disable(evlist);
 144                 perf_evlist__munmap(evlist);
 145                 perf_evlist__close(evlist);
 146                 perf_evlist__delete(evlist);
 147         }
 148         if (cpus)
 149                 cpu_map__delete(cpus);
 150         if (threads)
 151                 thread_map__delete(threads);
 152
 153         return err;
 154 }