LXR linux/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
   8int 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;
  53out_close_fd:
  54        perf_evsel__close_fd(evsel, 1, threads->nr);
  55out_evsel_delete:
  56        perf_evsel__delete(evsel);
  57out_thread_map_delete:
  58        thread_map__put(threads);
  59        return err;
  60}
  61