tsan: remove sleeps from tests

Even sleep(1) lead to episodical flakes on some machines.
Use an invisible by tsan barrier to enforce required execution order instead.
This makes the tests deterministic and faster.

llvm-svn: 226659

1 files changed, 19 insertions, 11 deletions

diff --git a/compiler-rt/test/tsan/load_shared_lib.cc b/compiler-rt/test/tsan/load_shared_lib.cc
index a27dc1cc6ff..b7934b82df7 100644
--- a/compiler-rt/test/tsan/load_shared_lib.cc
+++ b/compiler-rt/test/tsan/load_shared_lib.cc
@@ -7,35 +7,39 @@
 
 #ifdef BUILD_SO
 
-#include <stddef.h>
-#include <unistd.h>
+#include "test.h"
 
 int GLOB_SHARED = 0;
 
 extern "C"
+void init_so() {
+  barrier_init(&barrier, 2);
+}
+
+extern "C"
 void *write_from_so(void *unused) {
-  if (unused)
-    sleep(1);
+  if (unused == 0)
+    barrier_wait(&barrier);
   GLOB_SHARED++;
+  if (unused != 0)
+    barrier_wait(&barrier);
   return NULL;
 }
 
 #else  // BUILD_SO
 
+#include "test.h"
 #include <dlfcn.h>
-#include <pthread.h>
-#include <stdio.h>
-#include <stddef.h>
-#include <unistd.h>
-
 #include <string>
 
 int GLOB = 0;
 
 void *write_glob(void *unused) {
-  if (unused)
-    sleep(1);
+  if (unused == 0)
+    barrier_wait(&barrier);
   GLOB++;
+  if (unused != 0)
+    barrier_wait(&barrier);
   return NULL;
 }
 
@@ -48,6 +52,7 @@ void race_two_threads(void *(*access_callback)(void *unused)) {
 }
 
 int main(int argc, char *argv[]) {
+  barrier_init(&barrier, 2);
   std::string path = std::string(argv[0]) + std::string("-so.so");
   race_two_threads(write_glob);
   // CHECK: write_glob
@@ -56,6 +61,9 @@ int main(int argc, char *argv[]) {
     printf("error in dlopen(): %s\n", dlerror());
     return 1;
   }
+  void (*init_so)();
+  *(void **)&init_so = dlsym(lib, "init_so");
+  init_so();
   void *(*write_from_so)(void *unused);
   *(void **)&write_from_so = dlsym(lib, "write_from_so");
   race_two_threads(write_from_so);