kernel/tools/perf/tests/openat-syscall.c

   1 #include <api/fs/tracing_path.h>
   2 #include <linux/err.h>
   3 #include "thread_map.h"
   4 #include "evsel.h"
   5 #include "debug.h"
   6 #include "tests.h"
   7
   8 int test__openat_syscall_event(void)
   9 {
  10         int err = -1, fd;
  11         struct perf_evsel *evsel;
  12         unsigned int nr_openat_calls = 111, i;
  13         struct thread_map *threads = thread_map__new(-1, getpid(), UINT_MAX);
  14         char sbuf[STRERR_BUFSIZE];
  15         char errbuf[BUFSIZ];
  16
  17         if (threads == NULL) {
  18                 pr_debug("thread_map__new\n");
  19                 return -1;
  20         }
  21
  22         evsel = perf_evsel__newtp("syscalls", "sys_enter_openat");
  23         if (IS_ERR(evsel)) {
  24                 tracing_path__strerror_open_tp(errno, errbuf, sizeof(errbuf), "syscalls", "sys_enter_openat");
  25                 pr_debug("%s\n", errbuf);
  26                 goto out_thread_map_delete;
  27         }
  28
  29         if (perf_evsel__open_per_thread(evsel, threads) < 0) {
  30                 pr_debug("failed to open counter: %s, "
  31                          "tweak /proc/sys/kernel/perf_event_paranoid?\n",
  32                          strerror_r(errno, sbuf, sizeof(sbuf)));
  33                 goto out_evsel_delete;
  34         }
  35
  36         for (i = 0; i < nr_openat_calls; ++i) {
  37                 fd = openat(0, "/etc/passwd", O_RDONLY);
  38                 close(fd);
  39         }
  40
  41         if (perf_evsel__read_on_cpu(evsel, 0, 0) < 0) {
  42                 pr_debug("perf_evsel__read_on_cpu\n");
  43                 goto out_close_fd;
  44         }
  45
  46         if (perf_counts(evsel->counts, 0, 0)->val != nr_openat_calls) {
  47                 pr_debug("perf_evsel__read_on_cpu: expected to intercept %d calls, got %" PRIu64 "\n",
  48                          nr_openat_calls, perf_counts(evsel->counts, 0, 0)->val);
  49                 goto out_close_fd;
  50         }
  51
  52         err = 0;
  53 out_close_fd:
  54         perf_evsel__close_fd(evsel, 1, threads->nr);
  55 out_evsel_delete:
  56         perf_evsel__delete(evsel);
  57 out_thread_map_delete:
  58         thread_map__put(threads);
  59         return err;
  60 }