gecko-dev/xpcom/tests/gtest/TestRWLock.cpp

84 строки
2.3 KiB
C++

/* -*- 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/RWLock.h"
#include "gtest/gtest.h"
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("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_TRUE(NS_SUCCEEDED(rv));
}
EXPECT_EQ(data, (sOuterIterations / sWriteLockIteration) * sNumThreads);
}