compiler-rt/test/tsan/must_deadlock.cpp

   1 // Test that the deadlock detector can find a deadlock that actually happened.
   2 // Currently we will fail to report such a deadlock because we check for
   3 // cycles in lock-order graph after pthread_mutex_lock.
   4
   5 // RUN: %clangxx_tsan %s -o %t
   6 // RUN: not %run %t 2>&1 | FileCheck %s
   7 // XFAIL: *
   8 #include <pthread.h>
   9 #include <stdio.h>
  10 #include <unistd.h>
  11
  12 pthread_mutex_t mu1, mu2;
  13 pthread_barrier_t barrier;
  14
  15 void *Thread(void *p) {
  16   // mu2 => mu1
  17   pthread_mutex_lock(&mu2);
  18   pthread_barrier_wait(&barrier);
  19   pthread_mutex_lock(&mu1);
  20   // CHECK: ThreadSanitizer: lock-order-inversion (potential deadlock)
  21   pthread_mutex_unlock(&mu1);
  22   pthread_mutex_unlock(&mu2);
  23   return p;
  24 }
  25
  26 int main() {
  27   pthread_mutex_init(&mu1, NULL);
  28   pthread_mutex_init(&mu2, NULL);
  29   pthread_barrier_init(&barrier, 0, 2);
  30
  31   fprintf(stderr, "This test is going to deadlock and die in 3 seconds\n");
  32   alarm(3);
  33
  34   pthread_t t;
  35   pthread_create(&t, 0, Thread, 0);
  36
  37   // mu1 => mu2
  38   pthread_mutex_lock(&mu1);
  39   pthread_barrier_wait(&barrier);
  40   pthread_mutex_lock(&mu2);
  41   pthread_mutex_unlock(&mu2);
  42   pthread_mutex_unlock(&mu1);
  43
  44   pthread_join(t, 0);
  45
  46   pthread_mutex_destroy(&mu1);
  47   pthread_mutex_destroy(&mu2);
  48   pthread_barrier_destroy(&barrier);
  49   fprintf(stderr, "FAILED\n");
  50 }