ywkaras commented on code in PR #9394: URL: https://github.com/apache/trafficserver/pull/9394#discussion_r1112470722
########## src/tscpp/util/unit_tests/test_Bravo.cc: ########## @@ -0,0 +1,192 @@ +/** @file + + Unit tests for BRAVO + + @section license License + + 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 "catch.hpp" +#include "tscpp/util/Bravo.h" + +#include <chrono> +#include <mutex> +#include <shared_mutex> +#include <thread> + +using namespace std::chrono_literals; + +TEST_CASE("BRAVO - simple check with try-lock", "[libts][BRAVO]") +{ + SECTION("reader-reader") + { + ts::bravo::shared_mutex mutex; + ts::bravo::shared_lock<ts::bravo::shared_mutex> lock(mutex); + CHECK(lock.owns_lock() == true); + + std::thread t{[](ts::bravo::shared_mutex &mutex) { + ts::bravo::Token token{0}; + CHECK(mutex.try_lock_shared(token) == true); + mutex.unlock_shared(token); + }, + std::ref(mutex)}; + + t.join(); + } + + SECTION("reader-writer") + { + ts::bravo::shared_mutex mutex; + ts::bravo::shared_lock<ts::bravo::shared_mutex> lock(mutex); + CHECK(lock.owns_lock() == true); + + std::thread t{[](ts::bravo::shared_mutex &mutex) { CHECK(mutex.try_lock() == false); }, std::ref(mutex)}; + + t.join(); + } + + SECTION("writer-reader") + { + ts::bravo::shared_mutex mutex; + std::lock_guard<ts::bravo::shared_mutex> lock(mutex); + + std::thread t{[](ts::bravo::shared_mutex &mutex) { + ts::bravo::Token token{0}; + CHECK(mutex.try_lock_shared(token) == false); + CHECK(token == 0); + }, + std::ref(mutex)}; + + t.join(); + } + + SECTION("writer-writer") + { + ts::bravo::shared_mutex mutex; + std::lock_guard<ts::bravo::shared_mutex> lock(mutex); + + std::thread t{[](ts::bravo::shared_mutex &mutex) { CHECK(mutex.try_lock() == false); }, std::ref(mutex)}; + + t.join(); + } +} + +TEST_CASE("BRAVO - check with race", "[libts][BRAVO]") +{ + SECTION("reader-reader") + { + ts::bravo::shared_mutex mutex; + int i = 0; + + std::thread t1{[&](ts::bravo::shared_mutex &mutex) { + ts::bravo::shared_lock<ts::bravo::shared_mutex> lock(mutex); + CHECK(lock.owns_lock() == true); + ++i; + }, + std::ref(mutex)}; + + std::thread t2{[&](ts::bravo::shared_mutex &mutex) { + ts::bravo::shared_lock<ts::bravo::shared_mutex> lock(mutex); + CHECK(lock.owns_lock() == true); + ++i; + }, + std::ref(mutex)}; + + t1.join(); + t2.join(); + + CHECK(i == 2); Review Comment: Hmm why take a shared lock to write? Seems like `i` could end up being 1 not 2. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
