Status ModuleShutdown(volatile ModuleInitState* initState, void (*shutdown)())
{
for(;;)
{
if(cpu_CAS(initState, INITIALIZED, BUSY))
{
shutdown();
*initState = UNINITIALIZED;
COMPILER_FENCE;
return INFO::OK;
}
const ModuleInitState latchedInitState = *initState;
if(latchedInitState == INITIALIZED || latchedInitState == BUSY)
{
cpu_Pause();
continue;
}
if(latchedInitState == UNINITIALIZED)
return INFO::SKIPPED;
ENSURE(latchedInitState < 0);
return (Status)latchedInitState;
}
}
// NB: callers should skip this if *idxDeleterOut != 0 (avoids the overhead
// of an unnecessary indirect function call)
void RegisterUniqueRangeDeleter(UniqueRangeDeleter deleter, volatile IdxDeleter* idxDeleterOut)
{
ENSURE(deleter);
if(!cpu_CAS(idxDeleterOut, idxDeleterNone, -1)) // not the first call for this deleter
{
// wait until an index has been assigned
while(*idxDeleterOut <= 0)
cpu_Pause();
return;
}
const IdxDeleter idxDeleter = cpu_AtomicAdd(&numDeleters, 1);
ENSURE(idxDeleter < (IdxDeleter)ARRAY_SIZE(deleters));
deleters[idxDeleter] = deleter;
COMPILER_FENCE;
*idxDeleterOut = idxDeleter;
}
Status ModuleInit(volatile ModuleInitState* initState, Status (*init)())
{
for(;;)
{
if(cpu_CAS(initState, UNINITIALIZED, BUSY))
{
Status ret = init();
*initState = (ret == INFO::OK)? INITIALIZED : ret;
COMPILER_FENCE;
return ret;
}
const ModuleInitState latchedInitState = *initState;
if(latchedInitState == UNINITIALIZED || latchedInitState == BUSY)
{
cpu_Pause();
continue;
}
ENSURE(latchedInitState == INITIALIZED || latchedInitState < 0);
return (Status)latchedInitState;
}
}
