multithreading - 如何在不输入的情况下测试临界区是否被锁定？或者，如何等到 critsec 被另一个线程拥有？

Question

出于开发目的，我正在努力强制某些死锁场景持续重现。在这样做时，能够让一个线程等待一个关键部分被另一个线程锁定，然后强制它阻塞，这将很有帮助。

所以，我想要这样的东西:

void TryToWaitForBlock(CriticalSection& cs, DWORD ms)
{
    // wait until this CS is blocked, then return
}

...

void someFunction()
{
    // ...
    TryToWaitForBlock(cs, 5000);// this will give much more time for the crit sec to block by other threads, increasing the chance that the next call will block.
    EnterCriticalSection(cs);// normally this /very/ rarely blocks. When it does, it deadlocks.
    // ...
}

TryEnterCriticalSection 会是完美的，但是因为它实际上会进入临界区，所以不可用。是否有类似的功能可以进行测试，但不尝试输入它？

Answer 1

bool TryToWaitForBlock( CRITICAL_SECTION& cs, DWORD ms ) 
{
    LARGE_INTEGER freq;
    QueryPerformanceFrequency( &freq );

    LARGE_INTEGER now;
    QueryPerformanceCounter( &now );

    LARGE_INTEGER waitTill;
    waitTill.QuadPart = static_cast<LONGLONG>(now.QuadPart + freq.QuadPart * (ms / 1000.0));

    while( now.QuadPart < waitTill.QuadPart ) {
        if( NULL != static_cast<volatile HANDLE&>(cs.OwningThread) ) {
            return true;
        }

        QueryPerformanceCounter( &now );
    }

    return false;
}