| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License. |
| |
| #include "kudu/util/countdown_latch.h" |
| |
| #include <functional> |
| #include <memory> |
| #include <thread> |
| |
| #include <gtest/gtest.h> |
| |
| #include "kudu/util/monotime.h" |
| #include "kudu/util/test_macros.h" |
| #include "kudu/util/threadpool.h" |
| |
| using std::thread; |
| using std::unique_ptr; |
| |
| namespace kudu { |
| |
| static void DecrementLatch(CountDownLatch* latch, int amount) { |
| if (amount == 1) { |
| latch->CountDown(); |
| return; |
| } |
| latch->CountDown(amount); |
| } |
| |
| // Tests that we can decrement the latch by arbitrary amounts, as well |
| // as 1 by one. |
| TEST(TestCountDownLatch, TestLatch) { |
| unique_ptr<ThreadPool> pool; |
| ASSERT_OK(ThreadPoolBuilder("cdl-test").set_max_threads(1).Build(&pool)); |
| |
| CountDownLatch latch(1000); |
| |
| // Decrement the count by 1 in another thread, this should not fire the |
| // latch. |
| ASSERT_OK(pool->Submit([&latch]() { DecrementLatch(&latch, 1); })); |
| ASSERT_FALSE(latch.WaitFor(MonoDelta::FromMilliseconds(200))); |
| ASSERT_EQ(999, latch.count()); |
| |
| // Now decrement by 1000 this should decrement to 0 and fire the latch |
| // (even though 1000 is one more than the current count). |
| ASSERT_OK(pool->Submit([&latch]() { DecrementLatch(&latch, 1000); })); |
| latch.Wait(); |
| ASSERT_EQ(0, latch.count()); |
| } |
| |
| // Test that resetting to zero while there are waiters lets the waiters |
| // continue. |
| TEST(TestCountDownLatch, TestResetToZero) { |
| CountDownLatch cdl(100); |
| thread t([&]() { cdl.Wait(); }); |
| |
| // Sleep for a bit until it's likely the other thread is waiting on the latch. |
| SleepFor(MonoDelta::FromMilliseconds(10)); |
| cdl.Reset(0); |
| t.join(); |
| } |
| |
| } // namespace kudu |