tsan: add a stress test

[dvyukov]

Summary

The stress test does various assorted things
(memory accesses, function calls, atomic operations,
thread creation/join, intercepted libc calls)
in multiple threads just to stress various parts
of the runtime.

[melver]

compiler-rt/test/tsan/stress.cpp

18

Probably better if stop is volatile to not leave this to chance, assuming you don't want this to be atomic in case it could introduce unwanted effects.

Or add a compiler barrier.

[dvyukov]

made stop volatile

[dvyukov]

FTR, I've sent https://reviews.llvm.org/D110423 to fix MacOS buildbots.

compiler-rt/test/tsan/stress.cpp

+// RUN: %clangxx_tsan -O1 %s -o %t && %env_tsan_opts="flush_memory_ms=1 flush_symbolizer_ms=1 memory_limit_mb=1" %run %t 2>&1 | FileCheck %s
+#include "test.h"
+#include <fcntl.h>
+#include <string.h>
+
+volatile long stop;
+long atomic, read_only;
+int fds[2];
+
+__attribute__((noinline)) void *SecondaryThread(void *x) {
+  __atomic_fetch_add(&atomic, 1, __ATOMIC_ACQ_REL);
+  return NULL;
+}
+
+void *Thread(void *x) {
+  const int me = (long)x;
+  volatile long sink = 0;
+  while (!stop) {
+    // If me == 0, we do all of the following,
+    // otherwise only 1 type of action.
+    if (me == 0 || me == 1) {
+      // just read the stop variable
+    }
+    if (me == 0 || me == 2) {
+      __atomic_store_n(&atomic, 1, __ATOMIC_RELEASE);
+    }
+    if (me == 0 || me == 3) {
+      sink += __atomic_fetch_add(&atomic, 1, __ATOMIC_ACQ_REL);
+    }
+    if (me == 0 || me == 4) {
+      SecondaryThread(NULL);
+    }
+    if (me == 0 || me == 5) {
+      write(fds[1], fds, 1);
+    }
+    if (me == 0 || me == 6) {
+      char buf[2];
+      read(fds[0], &buf, sizeof(buf));
+    }
+    if (me == 0 || me == 7) {
+      pthread_t th;
+      pthread_create(&th, NULL, SecondaryThread, NULL);
+      pthread_join(th, NULL);
+    }
+    if (me == 0 || me == 8) {
+      long buf;
+      memcpy(&buf, &read_only, sizeof(buf));
+      sink += buf;
+    }
+    // If you add more actions, update kActions in main.
+  }
+  return NULL;
+}
+
+int main() {
+  ANNOTATE_BENIGN_RACE(stop);
+  if (pipe2(fds, O_NONBLOCK))
+    exit((perror("pipe2"), 1));
+  const int kActions = 9;
+  const int kMultiplier = 4;
+  pthread_t t[kActions * kMultiplier];
+  for (int i = 0; i < kActions * kMultiplier; i++)
+    pthread_create(&t[i], NULL, Thread, (void *)(long)(i % kActions));
+  sleep(5);
+  stop = 1;
+  for (int i = 0; i < kActions * kMultiplier; i++)
+    pthread_join(t[i], NULL);
+  fprintf(stderr, "DONE\n");
+  return 0;
+}
+
+// CHECK-NOT: ThreadSanitizer:
+// CHECK: DONE
+// CHECK-NOT: ThreadSanitizer:

compiler-rt/test/tsan/test.h

 void AnnotateIgnoreWritesEnd(const char *f, int l);
 
 void AnnotateIgnoreSyncBegin(const char *f, int l);
 void AnnotateIgnoreSyncEnd(const char *f, int l);
 
 void AnnotateHappensBefore(const char *f, int l, void *addr);
 void AnnotateHappensAfter(const char *f, int l, void *addr);
 
-void AnnotateBenignRaceSized(const char *f, int l, void *mem, unsigned int size, const char *desc);
-void WTFAnnotateBenignRaceSized(const char *f, int l, void *mem, unsigned int size, const char *desc);
+void AnnotateBenignRaceSized(const char *f, int l, const volatile void *mem,
+                             unsigned int size, const char *desc);
+void WTFAnnotateBenignRaceSized(const char *f, int l, const volatile void *mem,
+                                unsigned int size, const char *desc);
 
 #ifdef __cplusplus
 }
 #endif
 
 #define ANNOTATE_RWLOCK_CREATE(m) \
     AnnotateRWLockCreate(__FILE__, __LINE__, m)
 #define ANNOTATE_RWLOCK_CREATE_STATIC(m) \