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Diffstat (limited to 'xpcom/tests/gtest/TestRWLock.cpp')
| -rw-r--r-- | xpcom/tests/gtest/TestRWLock.cpp | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/xpcom/tests/gtest/TestRWLock.cpp b/xpcom/tests/gtest/TestRWLock.cpp new file mode 100644 index 0000000000..eee392f709 --- /dev/null +++ b/xpcom/tests/gtest/TestRWLock.cpp @@ -0,0 +1,214 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "nsThreadUtils.h" +#include "mozilla/Atomics.h" +#include "mozilla/gtest/MozAssertions.h" +#include "mozilla/RWLock.h" +#include "mozilla/SyncRunnable.h" +#include "nsIThread.h" +#include "gtest/gtest.h" + +using mozilla::AutoReadLock; +using mozilla::AutoTryReadLock; +using mozilla::AutoTryWriteLock; +using mozilla::AutoWriteLock; +using mozilla::RWLock; + +static const size_t sNumThreads = 4; +static const size_t sOuterIterations = 100; +static const size_t sInnerIterations = 100; +static const size_t sWriteLockIteration = 10; + +// Based on example code from _Programming with POSIX Threads_. Not an actual +// test of correctness, but more of a "does this work at all" sort of test. + +class RWLockRunnable : public mozilla::Runnable { + public: + RWLockRunnable(RWLock* aRWLock, mozilla::Atomic<size_t>* aSharedData) + : mozilla::Runnable("RWLockRunnable"), + mRWLock(aRWLock), + mSharedData(aSharedData) {} + + NS_DECL_NSIRUNNABLE + + private: + ~RWLockRunnable() = default; + + RWLock* mRWLock; + mozilla::Atomic<size_t>* mSharedData; +}; + +NS_IMETHODIMP +RWLockRunnable::Run() { + for (size_t i = 0; i < sOuterIterations; ++i) { + if (i % sWriteLockIteration == 0) { + mozilla::AutoWriteLock lock(*mRWLock); + + ++(*mSharedData); + } else { + mozilla::AutoReadLock lock(*mRWLock); + + // Loop and try to force other threads to run, but check that our + // shared data isn't being modified by them. + size_t initialValue = *mSharedData; + for (size_t j = 0; j < sInnerIterations; ++j) { + EXPECT_EQ(initialValue, *mSharedData); + + // This is a magic yield call. + PR_Sleep(PR_INTERVAL_NO_WAIT); + } + } + } + + return NS_OK; +} + +TEST(RWLock, SmokeTest) +{ + nsCOMPtr<nsIThread> threads[sNumThreads]; + RWLock rwlock MOZ_UNANNOTATED("test lock"); + mozilla::Atomic<size_t> data(0); + + for (size_t i = 0; i < sNumThreads; ++i) { + nsCOMPtr<nsIRunnable> event = new RWLockRunnable(&rwlock, &data); + NS_NewNamedThread("RWLockTester", getter_AddRefs(threads[i]), event); + } + + // Wait for all the threads to finish. + for (size_t i = 0; i < sNumThreads; ++i) { + nsresult rv = threads[i]->Shutdown(); + EXPECT_NS_SUCCEEDED(rv); + } + + EXPECT_EQ(data, (sOuterIterations / sWriteLockIteration) * sNumThreads); +} + +template <typename Function> +static std::invoke_result_t<Function> RunOnBackgroundThread( + Function&& aFunction) { + using Result = std::invoke_result_t<Function>; + nsCOMPtr<nsISerialEventTarget> thread; + MOZ_ALWAYS_SUCCEEDS(NS_CreateBackgroundTaskQueue( + "TestRWLock Background Thread", getter_AddRefs(thread))); + mozilla::Maybe<Result> tryResult; + RefPtr<nsIRunnable> runnable = + NS_NewRunnableFunction(__func__, [&] { tryResult.emplace(aFunction()); }); + MOZ_ALWAYS_SUCCEEDS( + mozilla::SyncRunnable::DispatchToThread(thread.get(), runnable)); + return *tryResult; +} + +TEST(RWLock, AutoTryReadLock) +{ + RWLock l1 MOZ_UNANNOTATED("autotryreadlock"); + { + AutoTryReadLock autol1(l1); + + EXPECT_TRUE(autol1); + + AutoTryReadLock autol2(l1); + EXPECT_TRUE(autol2); + + EXPECT_TRUE(RunOnBackgroundThread([&] { + AutoTryReadLock lock(l1); + return !!lock; + })); + + EXPECT_TRUE(autol1); + EXPECT_TRUE(autol2); + + { + RWLock l2 MOZ_UNANNOTATED("autotryreadlock2"); + AutoTryReadLock autol3(l2); + + EXPECT_TRUE(autol3); + } + + EXPECT_TRUE(autol1); + EXPECT_TRUE(autol2); + } + + { + AutoWriteLock autol4(l1); + MOZ_ASSERT(l1.LockedForWritingByCurrentThread()); + + AutoTryReadLock autol5(l1); + EXPECT_FALSE(autol5); + + EXPECT_FALSE(RunOnBackgroundThread([&] { + AutoTryReadLock lock(l1); + return !!lock; + })); + } + + AutoTryReadLock autol6(l1); + EXPECT_TRUE(autol6); + + EXPECT_TRUE(RunOnBackgroundThread([&] { + AutoTryReadLock lock(l1); + return !!lock; + })); +} + +TEST(RWLock, AutoTryWriteLock) +{ + RWLock l1 MOZ_UNANNOTATED("autotrywritelock"); + { + AutoTryWriteLock autol1(l1); + + EXPECT_TRUE(autol1); + + AutoTryReadLock autol2(l1); + EXPECT_FALSE(autol2); + + EXPECT_FALSE(RunOnBackgroundThread([&] { + AutoTryWriteLock lock(l1); + return !!lock; + })); + + EXPECT_TRUE(autol1); + EXPECT_FALSE(autol2); + + { + RWLock l2 MOZ_UNANNOTATED("autotrywritelock2"); + AutoTryWriteLock autol3(l2); + + EXPECT_TRUE(autol3); + } + + EXPECT_TRUE(autol1); + EXPECT_FALSE(autol2); + } + + { + AutoReadLock autol4(l1); + + AutoTryWriteLock autol5(l1); + EXPECT_FALSE(autol5); + + EXPECT_FALSE(RunOnBackgroundThread([&] { + AutoTryWriteLock lock(l1); + return !!lock; + })); + } + + { + AutoWriteLock autol6(l1); + MOZ_ASSERT(l1.LockedForWritingByCurrentThread()); + + AutoTryWriteLock autol7(l1); + EXPECT_FALSE(autol7); + + EXPECT_FALSE(RunOnBackgroundThread([&] { + AutoTryWriteLock lock(l1); + return !!lock; + })); + } + + AutoTryWriteLock autol8(l1); + EXPECT_TRUE(autol8); +} |