Source/wtf/SpinLockTest.cpp

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#include "config.h"
#include "wtf/SpinLock.h"

#include "wtf/Threading.h"
#include <gtest/gtest.h>

namespace {

static const size_t bufferSize = 16;

static int lock = 0;

static void fillBuffer(volatile char* buffer, char fillPattern)
{
    for (int i = 0; i < bufferSize; ++i)
        buffer[i] = fillPattern;
}

static void changeAndCheckBuffer(volatile char* buffer)
{
    fillBuffer(buffer, '\0');
    int total = 0;
    for (int i = 0; i < bufferSize; ++i)
        total += buffer[i];

    EXPECT_EQ(0, total);

    // This will mess with the other thread's calculation if we accidentally get
    // concurrency.
    fillBuffer(buffer, '!');
}

static void threadMain(void* arg)
{
    volatile char* buffer = reinterpret_cast<volatile char*>(arg);
    for (int i = 0; i < 500000; ++i) {
        spinLockLock(&lock);
        changeAndCheckBuffer(buffer);
        spinLockUnlock(&lock);
    }
}

TEST(WTF_SpinLock, Torture)
{
    char sharedBuffer[bufferSize];

    ThreadIdentifier thread1 = createThread(threadMain, sharedBuffer, "thread1");
    ThreadIdentifier thread2 = createThread(threadMain, sharedBuffer, "thread2");
    EXPECT_NE(0, thread1);
    EXPECT_NE(0, thread2);

    int ret = waitForThreadCompletion(thread1);
    EXPECT_EQ(0, ret);
    ret = waitForThreadCompletion(thread2);
    EXPECT_EQ(0, ret);
}

} // namespace