Copilot commented on code in PR #13439: URL: https://github.com/apache/trafficserver/pull/13439#discussion_r3691304632
########## src/iocore/eventsystem/unit_tests/test_Lock.cc: ########## @@ -0,0 +1,361 @@ +/** @file + + Catch2 unit tests for the Lock.h mutex acquisition macros. + + @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. + */ + +#define CATCH_CONFIG_THREAD_SAFE_ASSERTIONS +#include "inkevent_test_fixtures.h" + +using inkevent_test::AtomicFlag; +using inkevent_test::EventProcessorListener; + +CATCH_REGISTER_LISTENER(EventProcessorListener) + +namespace +{ + +class HoldOnEThread : public Continuation +{ +public: + HoldOnEThread(ProxyMutex *self_mutex, Ptr<ProxyMutex> &target) : Continuation(self_mutex), target_mutex(target) + { + SET_HANDLER(&HoldOnEThread::on_event); + } + + // In case of an exception in a thread that would have set release, we set + // it here in order to unfreeze any threads that may be waiting on done. + ~HoldOnEThread() + { + release.set(); + done.wait_until_set(); + } + + Ptr<ProxyMutex> target_mutex; + AtomicFlag held; + AtomicFlag release; + AtomicFlag done; + +private: + int + on_event(int /* event ATS_UNUSED */, void * /* data ATS_UNUSED */) + { + { + SCOPED_MUTEX_LOCK(guard, target_mutex, this_ethread()); + held.set(); + // Non-fatal so that done gets set. + CHECK(release.wait_until_set()); + } + done.set(); + return 0; + } +}; + +} // namespace + +TEST_CASE("MUTEX_TRY_LOCK on an unheld ProxyMutex constructs a guard whose is_locked() reports the successful acquisition", + "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + MUTEX_TRY_LOCK(guard, m, t); + + REQUIRE(guard.is_locked()); + REQUIRE(m->thread_holding == t); + REQUIRE(m->nthread_holding == 1); +} + +TEST_CASE("MUTEX_TRY_LOCK against a contended ProxyMutex constructs a guard whose is_locked() reports the failed acquisition", + "[inkevent][lock][multithread]") +{ + Ptr<ProxyMutex> contended{new_ProxyMutex()}; + Ptr<ProxyMutex> cont_self{new_ProxyMutex()}; + HoldOnEThread holder{cont_self.get(), contended}; + + REQUIRE(eventProcessor.schedule_imm(&holder, ET_CALL) != nullptr); + REQUIRE(holder.held.wait_until_set()); + + EThread *t = this_ethread(); + MUTEX_TRY_LOCK(guard, contended, t); + + REQUIRE_FALSE(guard.is_locked()); + + holder.release.set(); + REQUIRE(holder.done.wait_until_set()); +} + +TEST_CASE("MUTEX_TRY_LOCK by the holding thread is reentrant and returns a guard reporting is_locked() == true", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + MUTEX_TRY_LOCK(outer, m, t); + REQUIRE(outer.is_locked()); + REQUIRE(m->nthread_holding == 1); + + { + MUTEX_TRY_LOCK(inner, m, t); + REQUIRE(inner.is_locked()); + REQUIRE(m->nthread_holding == 2); + } + + REQUIRE(m->nthread_holding == 1); + REQUIRE(m->thread_holding == t); +} + +TEST_CASE("A MUTEX_TRY_LOCK guard releases the lock at scope exit, leaving the ProxyMutex unheld", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + { + MUTEX_TRY_LOCK(guard, m, t); + REQUIRE(guard.is_locked()); + } + + REQUIRE(m->nthread_holding == 0); + REQUIRE(m->thread_holding == nullptr); +} + +TEST_CASE("MUTEX_RELEASE on a MUTEX_TRY_LOCK guard releases the lock early and flips is_locked() to false", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + MUTEX_TRY_LOCK(guard, m, t); + REQUIRE(guard.is_locked()); + + MUTEX_RELEASE(guard); + + REQUIRE_FALSE(guard.is_locked()); + REQUIRE(m->nthread_holding == 0); + REQUIRE(m->thread_holding == nullptr); +} + +TEST_CASE("MUTEX_RELEASE invoked twice on the same MUTEX_TRY_LOCK guard is a no-op on the second call", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + MUTEX_TRY_LOCK(guard, m, t); + MUTEX_RELEASE(guard); + REQUIRE_FALSE(guard.is_locked()); + + MUTEX_RELEASE(guard); + + REQUIRE_FALSE(guard.is_locked()); + REQUIRE(m->nthread_holding == 0); +} + +TEST_CASE("SCOPED_MUTEX_LOCK on an unheld ProxyMutex acquires the lock during construction", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + SCOPED_MUTEX_LOCK(guard, m, t); + + REQUIRE(m->thread_holding == t); + REQUIRE(m->nthread_holding == 1); +} + +TEST_CASE("A SCOPED_MUTEX_LOCK guard releases the lock when its enclosing scope ends", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + { + SCOPED_MUTEX_LOCK(guard, m, t); + REQUIRE(m->nthread_holding == 1); + } + + REQUIRE(m->nthread_holding == 0); + REQUIRE(m->thread_holding == nullptr); +} + +TEST_CASE("SCOPED_MUTEX_LOCK is reentrant when the calling EThread already holds the lock", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + SCOPED_MUTEX_LOCK(outer, m, t); + REQUIRE(m->nthread_holding == 1); + + { + SCOPED_MUTEX_LOCK(inner, m, t); + REQUIRE(m->nthread_holding == 2); + REQUIRE(m->thread_holding == t); + } + + REQUIRE(m->nthread_holding == 1); + REQUIRE(m->thread_holding == t); +} + +TEST_CASE("MUTEX_RELEASE on a SCOPED_MUTEX_LOCK guard releases the lock early and renders the destructor a no-op", + "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + { + SCOPED_MUTEX_LOCK(guard, m, t); + MUTEX_RELEASE(guard); + + REQUIRE(m->nthread_holding == 0); + REQUIRE(m->thread_holding == nullptr); + } + + REQUIRE(m->nthread_holding == 0); + REQUIRE(m->thread_holding == nullptr); +} + +TEST_CASE("MUTEX_TAKE_LOCK acquires an unheld ProxyMutex and records the calling thread as its holder", "[inkevent][lock]") +{ + Ptr<ProxyMutex> m{new_ProxyMutex()}; + EThread *t = this_ethread(); + + MUTEX_TAKE_LOCK(m, t); + + REQUIRE(m->thread_holding == t); + REQUIRE(m->nthread_holding == 1); + + MUTEX_UNTAKE_LOCK(m, t); +} Review Comment: The test acquires a ProxyMutex via MUTEX_TAKE_LOCK but only unlocks it at the end of the test case. If any REQUIRE below the lock acquisition fails, stack unwinding will skip MUTEX_UNTAKE_LOCK and the ProxyMutex can be destroyed while its underlying ink_mutex is still locked (ProxyMutex::free() unconditionally calls ink_mutex_destroy), which is undefined behavior and can crash/hang the test runner. Add an RAII cleanup so the mutex is always released even when assertions throw. This issue also appears on line 248 of the same file. -- 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]
