tests/kqueue_close.c

   1 #include <unistd.h>
   2 #include <pthread.h>
   3 #include <errno.h>
   4
   5 #include <sys/event.h>
   6
   7 #include <darwintest.h>
   8
   9 T_GLOBAL_META(T_META_RUN_CONCURRENTLY(true));
  10
  11 /*
  12  * <rdar://problem/30231213> close() of kqueue FD races with kqueue_scan park
  13  *
  14  * When close concurrent with poll goes wrong, the close hangs
  15  * and the kevent never gets any more events.
  16  */
  17
  18 /* Both events should fire at about the same time */
  19 static uint32_t timeout_ms = 10;
  20
  21 static void *
  22 poll_kqueue(void *arg)
  23 {
  24         int fd = (int)arg;
  25
  26         struct kevent kev = {
  27                 .filter = EVFILT_TIMER,
  28                 .flags  = EV_ADD,
  29                 .data   = timeout_ms,
  30         };
  31
  32         int rv = kevent(fd, &kev, 1, NULL, 0, NULL);
  33
  34         if (rv == -1 && errno == EBADF) {
  35                 /* The close may race with this thread spawning */
  36                 T_LOG("kqueue already closed?");
  37                 return NULL;
  38         } else {
  39                 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "kevent");
  40         }
  41
  42         while ((rv = kevent(fd, NULL, 0, &kev, 1, NULL)) == 1) {
  43                 T_LOG("poll\n");
  44         }
  45
  46         if (rv != -1 || errno != EBADF) {
  47                 T_ASSERT_POSIX_SUCCESS(rv, "fd should be closed");
  48         }
  49
  50         return NULL;
  51 }
  52
  53 static void
  54 run_test()
  55 {
  56         int fd = kqueue();
  57         T_QUIET; T_ASSERT_POSIX_SUCCESS(fd, "kqueue");
  58
  59         pthread_t thread;
  60         int rv = pthread_create(&thread, NULL, poll_kqueue,
  61             (void *)(uintptr_t)fd);
  62         T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pthread_create");
  63
  64         usleep(timeout_ms * 1000);
  65
  66         rv = close(fd);
  67         T_ASSERT_POSIX_SUCCESS(rv, "close");
  68
  69         rv = pthread_join(thread, NULL);
  70         T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pthread_join");
  71 }
  72
  73 T_DECL(kqueue_close_race, "Races kqueue close with kqueue process",
  74     T_META_LTEPHASE(LTE_POSTINIT), T_META_TIMEOUT(5))
  75 {
  76         for (uint32_t i = 1; i < 100; i++) {
  77                 run_test();
  78         }
  79 }