Fix race in multiops txn stress test (#12847)

Summary:
`MultiOpsTxnsStressListener::OnCompactionCompleted()` access `db_` and can be called while db_ is being destroyed in ~StressTest(). This causes TSAN to complain about data race. This PR fixes this issue by calling db_->Close() first to stop all background work. Also moved the cleanup out of StressTest destructor to avoid race between the listener and  ~StressTest().

Pull Request resolved: #12847

Test Plan: monitor crash test failure.

Reviewed By: hx235

Differential Revision: D59492691

Pulled By: cbi42

fbshipit-source-id: afcbab084cc9ac0904d6b04809b0888498ca8e66

db_stress_tool/db_stress_test_base.cc

@@ -103,12 +103,16 @@ StressTest::StressTest()
   }
 }
 
-StressTest::~StressTest() {
+void StressTest::CleanUp() {
   for (auto cf : column_families_) {
     delete cf;
   }
   column_families_.clear();
+  if (db_) {
+    db_->Close();
+  }
   delete db_;
+  db_ = nullptr;
 
   for (auto* cf : cmp_cfhs_) {
     delete cf;

db_stress_tool/db_stress_test_base.h

@@ -27,7 +27,7 @@ class StressTest {
  public:
   StressTest();
 
-  virtual ~StressTest();
+  virtual ~StressTest() {}
 
   std::shared_ptr<Cache> NewCache(size_t capacity, int32_t num_shard_bits);
 
@@ -49,6 +49,8 @@ class StressTest {
            FLAGS_manual_wal_flush_one_in > 0;
   }
 
+  void CleanUp();
+
  protected:
   static int GetMinInjectedErrorCount(int error_count_1, int error_count_2) {
     if (error_count_1 > 0 && error_count_2 > 0) {

db_stress_tool/db_stress_tool.cc

@@ -362,11 +362,11 @@ int db_stress_tool(int argc, char** argv) {
   // Initialize the Zipfian pre-calculated array
   InitializeHotKeyGenerator(FLAGS_hot_key_alpha);
   shared.reset(new SharedState(db_stress_env, stress.get()));
-  if (RunStressTest(shared.get())) {
-    return 0;
-  } else {
-    return 1;
-  }
+  bool run_stress_test = RunStressTest(shared.get());
+  // Close DB in CleanUp() before destructor to prevent race between destructor
+  // and operations in listener callbacks (e.g. MultiOpsTxnsStressListener).
+  stress->CleanUp();
+  return run_stress_test ? 0 : 1;
 }
 
 }  // namespace ROCKSDB_NAMESPACE