LXR linux/tools/perf/tests/openat-syscall.c

   1#include "thread_map.h"
   2#include "evsel.h"
   3#include "debug.h"
   4#include "tests.h"
   5
   6int test__openat_syscall_event(void)
   7{
   8        int err = -1, fd;
   9        struct perf_evsel *evsel;
  10        unsigned int nr_openat_calls = 111, i;
  11        struct thread_map *threads = thread_map__new(-1, getpid(), UINT_MAX);
  12        char sbuf[STRERR_BUFSIZE];
  13
  14        if (threads == NULL) {
  15                pr_debug("thread_map__new\n");
  16                return -1;
  17        }
  18
  19        evsel = perf_evsel__newtp("syscalls", "sys_enter_openat");
  20        if (evsel == NULL) {
  21                if (tracefs_configured())
  22                        pr_debug("is tracefs mounted on /sys/kernel/tracing?\n");
  23                else if (debugfs_configured())
  24                        pr_debug("is debugfs mounted on /sys/kernel/debug?\n");
  25                else
  26                        pr_debug("Neither tracefs or debugfs is enabled in this kernel\n");
  27                goto out_thread_map_delete;
  28        }
  29
  30        if (perf_evsel__open_per_thread(evsel, threads) < 0) {
  31                pr_debug("failed to open counter: %s, "
  32                         "tweak /proc/sys/kernel/perf_event_paranoid?\n",
  33                         strerror_r(errno, sbuf, sizeof(sbuf)));
  34                goto out_evsel_delete;
  35        }
  36
  37        for (i = 0; i < nr_openat_calls; ++i) {
  38                fd = openat(0, "/etc/passwd", O_RDONLY);
  39                close(fd);
  40        }
  41
  42        if (perf_evsel__read_on_cpu(evsel, 0, 0) < 0) {
  43                pr_debug("perf_evsel__read_on_cpu\n");
  44                goto out_close_fd;
  45        }
  46
  47        if (perf_counts(evsel->counts, 0, 0)->val != nr_openat_calls) {
  48                pr_debug("perf_evsel__read_on_cpu: expected to intercept %d calls, got %" PRIu64 "\n",
  49                         nr_openat_calls, perf_counts(evsel->counts, 0, 0)->val);
  50                goto out_close_fd;
  51        }
  52
  53        err = 0;
  54out_close_fd:
  55        perf_evsel__close_fd(evsel, 1, threads->nr);
  56out_evsel_delete:
  57        perf_evsel__delete(evsel);
  58out_thread_map_delete:
  59        thread_map__put(threads);
  60        return err;
  61}
  62