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/*
* Copyright (C) 2015 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// On Mac, you can build this like so:
// clang++ -o LockSpeedTest Source/WTF/benchmarks/LockSpeedTest.cpp -O3 -W -ISource/WTF -LWebKitBuild/Release -lWTF -framework Foundation -licucore -std=c++11
#include "config.h"
#include <unistd.h>
#include <wtf/CurrentTime.h>
#include <wtf/Lock.h>
#include <wtf/StdLibExtras.h>
#include <wtf/Threading.h>
#include <wtf/ThreadingPrimitives.h>
#include <wtf/WordLock.h>
namespace {
// This is the old WTF::SpinLock class, included here so that we can still compare our new locks to a
// spinlock baseline.
class SpinLock {
public:
SpinLock()
{
m_lock.store(0, std::memory_order_relaxed);
}
void lock()
{
while (!m_lock.compareExchangeWeak(0, 1, std::memory_order_acquire))
std::this_thread::yield();
}
void unlock()
{
m_lock.store(0, std::memory_order_release);
}
bool isLocked() const
{
return m_lock.load(std::memory_order_acquire);
}
private:
Atomic<unsigned> m_lock;
};
unsigned numThreadGroups;
unsigned numThreadsPerGroup;
unsigned workPerCriticalSection;
unsigned numNoiseThreads;
unsigned numIterations;
NO_RETURN void usage()
{
printf("Usage: LockSpeedTest spinlock|wordlock|lock|mutex|all <num thread groups> <num threads per group> <work per critical section> <num noise threads> <num iterations>\n");
exit(1);
}
template<typename LockType>
void runBenchmark(const char* name)
{
std::unique_ptr<LockType[]> locks = std::make_unique<LockType[]>(numThreadGroups);
std::unique_ptr<double[]> words = std::make_unique<double[]>(numThreadGroups);
std::unique_ptr<ThreadIdentifier[]> threads = std::make_unique<ThreadIdentifier[]>(numThreadGroups * numThreadsPerGroup);
std::unique_ptr<ThreadIdentifier[]> noiseThreads = std::make_unique<ThreadIdentifier[]>(numNoiseThreads);
std::unique_ptr<double[]> noiseCounts = std::make_unique<double[]>(numNoiseThreads);
volatile bool shouldStop = false;
for (unsigned threadIndex = numNoiseThreads; threadIndex--;) {
noiseCounts[threadIndex] = 0;
noiseThreads[threadIndex] = createThread(
"Noise Thread",
[&shouldStop, &noiseCounts, threadIndex] () {
while (!shouldStop)
noiseCounts[threadIndex]++;
});
}
double before = monotonicallyIncreasingTimeMS();
for (unsigned threadGroupIndex = numThreadGroups; threadGroupIndex--;) {
words[threadGroupIndex] = 0;
for (unsigned threadIndex = numThreadsPerGroup; threadIndex--;) {
threads[threadGroupIndex * numThreadsPerGroup + threadIndex] = createThread(
"Benchmark thread",
[threadGroupIndex, &locks, &words] () {
for (unsigned i = numIterations; i--;) {
locks[threadGroupIndex].lock();
for (unsigned j = workPerCriticalSection; j--;) {
words[threadGroupIndex]++;
words[threadGroupIndex] *= 1.01;
}
locks[threadGroupIndex].unlock();
}
});
}
}
for (unsigned threadIndex = numThreadGroups * numThreadsPerGroup; threadIndex--;)
waitForThreadCompletion(threads[threadIndex]);
shouldStop = true;
double noiseCount = 0;
for (unsigned threadIndex = numNoiseThreads; threadIndex--;) {
waitForThreadCompletion(noiseThreads[threadIndex]);
noiseCount += noiseCounts[threadIndex];
}
double after = monotonicallyIncreasingTimeMS();
printf("%s: %.3lf ms, %.0lf noise.\n", name, after - before, noiseCount);
}
} // anonymous namespace
int main(int argc, char** argv)
{
WTF::initializeThreading();
if (argc != 7
|| sscanf(argv[2], "%u", &numThreadGroups) != 1
|| sscanf(argv[3], "%u", &numThreadsPerGroup) != 1
|| sscanf(argv[4], "%u", &workPerCriticalSection) != 1
|| sscanf(argv[5], "%u", &numNoiseThreads) != 1
|| sscanf(argv[6], "%u", &numIterations) != 1)
usage();
bool didRun = false;
if (!strcmp(argv[1], "spinlock") || !strcmp(argv[1], "all")) {
runBenchmark<SpinLock>("SpinLock");
didRun = true;
}
if (!strcmp(argv[1], "wordlock") || !strcmp(argv[1], "all")) {
runBenchmark<WordLock>("WTF WordLock");
didRun = true;
}
if (!strcmp(argv[1], "lock") || !strcmp(argv[1], "all")) {
runBenchmark<Lock>("WTF Lock");
didRun = true;
}
if (!strcmp(argv[1], "mutex") || !strcmp(argv[1], "all")) {
runBenchmark<Mutex>("Platform Mutex");
didRun = true;
}
if (!didRun)
usage();
return 0;
}
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