Method try_acquire

benchmarks/tbb/queuing_mutex.cpp:62–83

A method to acquire queuing_mutex if it is free

//! A method to acquire queuing_mutex if it is free
bool queuing_mutex::scoped_lock::try_acquire( queuing_mutex& m )
{
    __TBB_ASSERT( !this->mutex, "scoped_lock is already holding a mutex");

    // Must set all fields before the fetch_and_store, because once the
    // fetch_and_store executes, *this becomes accessible to other threads.
    next  = NULL;
    going = 0;

    // The CAS must have release semantics, because we are
    // "sending" the fields initialized above to other processors.
    if( m.q_tail.compare_and_swap<tbb::release>(this, NULL) )
        return false;

    // Force acquire so that user's critical section receives correct values
    // from processor that was previously in the user's critical section.
    // try_acquire should always have acquire semantic, even if failed.
    __TBB_load_with_acquire(going);
    mutex = &m;
    ITT_NOTIFY(sync_acquired, mutex);
    return true;
}

//! A method to release queuing_mutex lock
void queuing_mutex::scoped_lock::release( )