Merge pull request #1869 from cpeterso/master

rt: lock_and_signal fixes
This commit is contained in:
Brian Anderson 2012-02-19 23:42:38 -08:00
commit 657ef8ef60
1 changed files with 18 additions and 1 deletions

View File

@ -19,7 +19,18 @@ lock_and_signal::lock_and_signal()
: _holding_thread(INVALID_THREAD)
{
_event = CreateEvent(NULL, FALSE, FALSE, NULL);
InitializeCriticalSection(&_cs);
// If a CRITICAL_SECTION is not initialized with a spin count, it will
// default to 0, even on multi-processor systems. MSDN suggests using
// 4000. On single-processor systems, the spin count parameter is ignored
// and the critical section's spin count defaults to 0.
const DWORD SPIN_COUNT = 4000;
CHECKED(!InitializeCriticalSectionAndSpinCount(&_cs, SPIN_COUNT));
// TODO? Consider checking GetProcAddress("InitializeCriticalSectionEx")
// so Windows >= Vista we can use CRITICAL_SECTION_NO_DEBUG_INFO to avoid
// allocating CRITICAL_SECTION debug info that is never released. See:
// http://stackoverflow.com/questions/804848/critical-sections-leaking-memory-on-vista-win2008#889853
}
#else
@ -32,8 +43,10 @@ lock_and_signal::lock_and_signal()
#endif
lock_and_signal::~lock_and_signal() {
assert(_holding_thread == INVALID_THREAD);
#if defined(__WIN32__)
CloseHandle(_event);
DeleteCriticalSection(&_cs);
#else
CHECKED(pthread_cond_destroy(&_cond));
CHECKED(pthread_mutex_destroy(&_mutex));
@ -41,6 +54,7 @@ lock_and_signal::~lock_and_signal() {
}
void lock_and_signal::lock() {
assert(!lock_held_by_current_thread());
#if defined(__WIN32__)
EnterCriticalSection(&_cs);
_holding_thread = GetCurrentThreadId();
@ -51,6 +65,7 @@ void lock_and_signal::lock() {
}
void lock_and_signal::unlock() {
assert(lock_held_by_current_thread());
_holding_thread = INVALID_THREAD;
#if defined(__WIN32__)
LeaveCriticalSection(&_cs);
@ -69,9 +84,11 @@ void lock_and_signal::wait() {
LeaveCriticalSection(&_cs);
WaitForSingleObject(_event, INFINITE);
EnterCriticalSection(&_cs);
assert(_holding_thread == INVALID_THREAD);
_holding_thread = GetCurrentThreadId();
#else
CHECKED(pthread_cond_wait(&_cond, &_mutex));
assert(_holding_thread == INVALID_THREAD);
_holding_thread = pthread_self();
#endif
}