compiler-rt/test/tsan/signal_sync2.cpp

   1 // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
   2 // UNSUPPORTED: darwin
   3 // Fails episodically on powerpc bots:
   4 // https://lab.llvm.org/buildbot/#/builders/121/builds/13391
   5 // UNSUPPORTED: target=powerpc64{{.*}}
   6 #include "test.h"
   7 #include <errno.h>
   8 #include <signal.h>
   9 #include <sys/time.h>
  10 #include <sys/types.h>
  11
  12 // Test synchronization in signal handled within IgnoreSync region.
  13
  14 const int kSignalCount = 500;
  15
  16 __thread int process_signals;
  17 int signals_handled;
  18 int done;
  19 int ready[kSignalCount];
  20 long long data[kSignalCount];
  21
  22 static void handler(int sig) {
  23   if (!__atomic_load_n(&process_signals, __ATOMIC_RELAXED))
  24     return;
  25   int pos = signals_handled++;
  26   if (pos >= kSignalCount)
  27     return;
  28   data[pos] = pos;
  29   __atomic_store_n(&ready[pos], 1, __ATOMIC_RELEASE);
  30 }
  31
  32 static void* thr(void *p) {
  33   AnnotateIgnoreSyncBegin(__FILE__, __LINE__);
  34   __atomic_store_n(&process_signals, 1, __ATOMIC_RELAXED);
  35   while (!__atomic_load_n(&done, __ATOMIC_RELAXED)) {
  36   }
  37   AnnotateIgnoreSyncEnd(__FILE__, __LINE__);
  38   return 0;
  39 }
  40
  41 int main() {
  42   struct sigaction act = {};
  43   act.sa_handler = handler;
  44   if (sigaction(SIGPROF, &act, 0)) {
  45     perror("sigaction");
  46     exit(1);
  47   }
  48   itimerval t;
  49   t.it_value.tv_sec = 0;
  50   t.it_value.tv_usec = 10;
  51   t.it_interval = t.it_value;
  52   if (setitimer(ITIMER_PROF, &t, 0)) {
  53     perror("setitimer");
  54     exit(1);
  55   }
  56
  57   pthread_t th;
  58   pthread_create(&th, 0, thr, 0);
  59   for (int pos = 0; pos < kSignalCount; pos++) {
  60     while (__atomic_load_n(&ready[pos], __ATOMIC_ACQUIRE) == 0) {
  61     }
  62     if (data[pos] != pos) {
  63       printf("at pos %d, expect %d, got %lld\n", pos, pos, data[pos]);
  64       exit(1);
  65     }
  66   }
  67   __atomic_store_n(&done, 1, __ATOMIC_RELAXED);
  68   pthread_join(th, 0);
  69   fprintf(stderr, "DONE\n");
  70   return 0;
  71 }
  72
  73 // CHECK-NOT: WARNING: ThreadSanitizer:
  74 // CHECK: DONE