1 files changed, 111 insertions, 0 deletions
diff --git a/src/rocksdb/util/repeatable_thread_test.cc b/src/rocksdb/util/repeatable_thread_test.cc
new file mode 100644
index 000000000..0b3e95464
--- /dev/null
+++ b/src/rocksdb/util/repeatable_thread_test.cc
@@ -0,0 +1,111 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#include "util/repeatable_thread.h"
+
+#include <atomic>
+#include <memory>
+
+#include "db/db_test_util.h"
+#include "test_util/mock_time_env.h"
+#include "test_util/sync_point.h"
+#include "test_util/testharness.h"
+
+class RepeatableThreadTest : public testing::Test {
+ public:
+  RepeatableThreadTest()
+      : mock_clock_(std::make_shared<ROCKSDB_NAMESPACE::MockSystemClock>(
+            ROCKSDB_NAMESPACE::SystemClock::Default())) {}
+
+ protected:
+  std::shared_ptr<ROCKSDB_NAMESPACE::MockSystemClock> mock_clock_;
+};
+
+TEST_F(RepeatableThreadTest, TimedTest) {
+  constexpr uint64_t kSecond = 1000000;  // 1s = 1000000us
+  constexpr int kIteration = 3;
+  const auto& clock = ROCKSDB_NAMESPACE::SystemClock::Default();
+  ROCKSDB_NAMESPACE::port::Mutex mutex;
+  ROCKSDB_NAMESPACE::port::CondVar test_cv(&mutex);
+  int count = 0;
+  uint64_t prev_time = clock->NowMicros();
+  ROCKSDB_NAMESPACE::RepeatableThread thread(
+      [&] {
+        ROCKSDB_NAMESPACE::MutexLock l(&mutex);
+        count++;
+        uint64_t now = clock->NowMicros();
+        assert(count == 1 || prev_time + 1 * kSecond <= now);
+        prev_time = now;
+        if (count >= kIteration) {
+          test_cv.SignalAll();
+        }
+      },
+      "rt_test", clock.get(), 1 * kSecond);
+  // Wait for execution finish.
+  {
+    ROCKSDB_NAMESPACE::MutexLock l(&mutex);
+    while (count < kIteration) {
+      test_cv.Wait();
+    }
+  }
+
+  // Test cancel
+  thread.cancel();
+}
+
+TEST_F(RepeatableThreadTest, MockEnvTest) {
+  constexpr uint64_t kSecond = 1000000;  // 1s = 1000000us
+  constexpr int kIteration = 3;
+  mock_clock_->SetCurrentTime(0);  // in seconds
+  std::atomic<int> count{0};
+
+#if defined(OS_MACOSX) && !defined(NDEBUG)
+  ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
+  ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
+  ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
+      "InstrumentedCondVar::TimedWaitInternal", [&](void* arg) {
+        // Obtain the current (real) time in seconds and add 1000 extra seconds
+        // to ensure that RepeatableThread::wait invokes TimedWait with a time
+        // greater than (real) current time. This is to prevent the TimedWait
+        // function from returning immediately without sleeping and releasing
+        // the mutex on certain platforms, e.g. OS X. If TimedWait returns
+        // immediately, the mutex will not be released, and
+        // RepeatableThread::TEST_WaitForRun never has a chance to execute the
+        // callback which, in this case, updates the result returned by
+        // mock_clock->NowMicros. Consequently, RepeatableThread::wait cannot
+        // break out of the loop, causing test to hang. The extra 1000 seconds
+        // is a best-effort approach because there seems no reliable and
+        // deterministic way to provide the aforementioned guarantee. By the
+        // time RepeatableThread::wait is called, it is no guarantee that the
+        // delay + mock_clock->NowMicros will be greater than the current real
+        // time. However, 1000 seconds should be sufficient in most cases.
+        uint64_t time_us = *reinterpret_cast<uint64_t*>(arg);
+        if (time_us < mock_clock_->RealNowMicros()) {
+          *reinterpret_cast<uint64_t*>(arg) =
+              mock_clock_->RealNowMicros() + 1000;
+        }
+      });
+  ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
+#endif  // OS_MACOSX && !NDEBUG
+
+  ROCKSDB_NAMESPACE::RepeatableThread thread(
+      [&] { count++; }, "rt_test", mock_clock_.get(), 1 * kSecond, 1 * kSecond);
+  for (int i = 1; i <= kIteration; i++) {
+    // Bump current time
+    thread.TEST_WaitForRun([&] { mock_clock_->SetCurrentTime(i); });
+  }
+  // Test function should be exectued exactly kIteraion times.
+  ASSERT_EQ(kIteration, count.load());
+
+  // Test cancel
+  thread.cancel();
+}
+
+int main(int argc, char** argv) {
+  ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
+  ::testing::InitGoogleTest(&argc, argv);
+
+  return RUN_ALL_TESTS();
+}