static
void RunBasicTest()
{
int value;
SDL_SpinLock lock = 0;
SDL_atomic_t v;
SDL_bool tfret = SDL_FALSE;
printf("\nspin lock---------------------------------------\n\n");
SDL_AtomicLock(&lock);
printf("AtomicLock lock=%d\n", lock);
SDL_AtomicUnlock(&lock);
printf("AtomicUnlock lock=%d\n", lock);
printf("\natomic -----------------------------------------\n\n");
SDL_AtomicSet(&v, 0);
tfret = SDL_AtomicSet(&v, 10) == 0;
printf("AtomicSet(10) tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
tfret = SDL_AtomicAdd(&v, 10) == 10;
printf("AtomicAdd(10) tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
SDL_AtomicSet(&v, 0);
SDL_AtomicIncRef(&v);
tfret = (SDL_AtomicGet(&v) == 1);
printf("AtomicIncRef() tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
SDL_AtomicIncRef(&v);
tfret = (SDL_AtomicGet(&v) == 2);
printf("AtomicIncRef() tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
tfret = (SDL_AtomicDecRef(&v) == SDL_FALSE);
printf("AtomicDecRef() tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
tfret = (SDL_AtomicDecRef(&v) == SDL_TRUE);
printf("AtomicDecRef() tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
SDL_AtomicSet(&v, 10);
tfret = (SDL_AtomicCAS(&v, 0, 20) == SDL_FALSE);
printf("AtomicCAS() tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
value = SDL_AtomicGet(&v);
tfret = (SDL_AtomicCAS(&v, value, 20) == SDL_TRUE);
printf("AtomicCAS() tfret=%s val=%d\n", tf(tfret), SDL_AtomicGet(&v));
}
void jrq_Write( JobRingQueue* queue, Job* jobby )
{
// TODO: Test to see if we're writing over the tail, and if we are then fail
bool writeSuccess = false;
while( !writeSuccess ) {
int idx = queue->head.value;
if( SDL_AtomicCAS( &( queue->head ), idx, ( idx + 1 ) % queue->size ) ) {
queue->ringBuffer[idx] = (*jobby);
writeSuccess = true;
}
}
}
static SDL_bool DequeueEvent_LockFree(SDL_EventQueue *queue, SDL_Event *event)
{
SDL_EventQueueEntry *entry;
unsigned queue_pos;
unsigned entry_seq;
int delta;
SDL_bool status;
#ifdef TEST_SPINLOCK_FIFO
/* This is a gate so an external thread can lock the queue */
SDL_AtomicLock(&queue->lock);
SDL_assert(SDL_AtomicGet(&queue->watcher) == 0);
SDL_AtomicIncRef(&queue->rwcount);
SDL_AtomicUnlock(&queue->lock);
#endif
queue_pos = (unsigned)SDL_AtomicGet(&queue->dequeue_pos);
for ( ; ; ) {
entry = &queue->entries[queue_pos & WRAP_MASK];
entry_seq = (unsigned)SDL_AtomicGet(&entry->sequence);
delta = (int)(entry_seq - (queue_pos + 1));
if (delta == 0) {
/* The entry and the queue position match, try to increment the queue position */
if (SDL_AtomicCAS(&queue->dequeue_pos, (int)queue_pos, (int)(queue_pos+1))) {
/* We own the object, fill it! */
*event = entry->event;
SDL_AtomicSet(&entry->sequence, (int)(queue_pos+MAX_ENTRIES));
status = SDL_TRUE;
break;
}
} else if (delta < 0) {
/* We ran into an old queue entry, which means we've hit empty */
status = SDL_FALSE;
break;
} else {
/* We ran into a new queue entry, get the new queue position */
queue_pos = (unsigned)SDL_AtomicGet(&queue->dequeue_pos);
}
}
#ifdef TEST_SPINLOCK_FIFO
SDL_AtomicDecRef(&queue->rwcount);
#endif
return status;
}
// do the next job available in the ring buffer, returns if anything was actually done
bool jrq_ProcessNext( JobRingQueue* queue )
{
int idx = queue->tail.value;
if( idx != queue->head.value ) {
if( SDL_AtomicCAS( &( queue->tail ), idx, ( idx + 1 ) % queue->size ) ) {
SDL_AtomicAdd( &( queue->busy ), 1 );
if( queue->ringBuffer[idx].process != NULL ) queue->ringBuffer[idx].process( queue->ringBuffer[idx].data );
queue->ringBuffer[idx].process = NULL; // invalidate the job
SDL_AtomicAdd( &( queue->busy ), -1 );
return true;
}
}
return false;
}
internal bool32
SDLDoNextWorkQueueEntry(platform_work_queue *Queue) {
bool32 WeShouldSleep = false;
int OriginalNextEntryToRead = Queue->NextEntryToRead.value;
int NewNextEntryToRead = (OriginalNextEntryToRead + 1) % ArrayCount(Queue->Entries);
if (OriginalNextEntryToRead != Queue->NextEntryToWrite.value) {
if (SDL_AtomicCAS(&Queue->NextEntryToRead, OriginalNextEntryToRead, NewNextEntryToRead)) {
platform_work_queue_entry Entry = Queue->Entries[OriginalNextEntryToRead];
Entry.Callback(Queue, Entry.Data);
SDL_AtomicIncRef(&Queue->CompletionCount);
}
} else {
WeShouldSleep = true;
}
return WeShouldSleep;
}
void
SDL_TimerQuit(void)
{
SDL_TimerData *data = &SDL_timer_data;
SDL_Timer *timer;
SDL_TimerMap *entry;
if (SDL_AtomicCAS(&data->active, 1, 0)) { /* active? Move to inactive. */
/* Shutdown the timer thread */
if (data->thread) {
SDL_SemPost(data->sem);
SDL_WaitThread(data->thread, NULL);
data->thread = NULL;
}
SDL_DestroySemaphore(data->sem);
data->sem = NULL;
/* Clean up the timer entries */
while (data->timers) {
timer = data->timers;
data->timers = timer->next;
SDL_free(timer);
}
while (data->freelist) {
timer = data->freelist;
data->freelist = timer->next;
SDL_free(timer);
}
while (data->timermap) {
entry = data->timermap;
data->timermap = entry->next;
SDL_free(entry);
}
SDL_DestroyMutex(data->timermap_lock);
data->timermap_lock = NULL;
}
}
/*
* Sys_Atomic_CAS
*/
bool Sys_Atomic_CAS( volatile int *value, int oldval, int newval, qmutex_t *mutex )
{
return SDL_AtomicCAS( ( SDL_atomic_t * )value, newval, oldval ) == SDL_TRUE;
}
static
void RunEpicTest()
{
int b;
atomicValue v;
printf("\nepic test---------------------------------------\n\n");
printf("Size asserted to be >= 32-bit\n");
SDL_assert(sizeof(atomicValue)>=4);
printf("Check static initializer\n");
v=SDL_AtomicGet(&good);
SDL_assert(v==42);
SDL_assert(bad==42);
printf("Test negative values\n");
SDL_AtomicSet(&good, -5);
v=SDL_AtomicGet(&good);
SDL_assert(v==-5);
printf("Verify maximum value\n");
SDL_AtomicSet(&good, CountTo);
v=SDL_AtomicGet(&good);
SDL_assert(v==CountTo);
printf("Test compare and exchange\n");
b=SDL_AtomicCAS(&good, 500, 43);
SDL_assert(!b); /* no swap since CountTo!=500 */
v=SDL_AtomicGet(&good);
SDL_assert(v==CountTo); /* ensure no swap */
b=SDL_AtomicCAS(&good, CountTo, 44);
SDL_assert(!!b); /* will swap */
v=SDL_AtomicGet(&good);
SDL_assert(v==44);
printf("Test Add\n");
v=SDL_AtomicAdd(&good, 1);
SDL_assert(v==44);
v=SDL_AtomicGet(&good);
SDL_assert(v==45);
v=SDL_AtomicAdd(&good, 10);
SDL_assert(v==45);
v=SDL_AtomicGet(&good);
SDL_assert(v==55);
printf("Test Add (Negative values)\n");
v=SDL_AtomicAdd(&good, -20);
SDL_assert(v==55);
v=SDL_AtomicGet(&good);
SDL_assert(v==35);
v=SDL_AtomicAdd(&good, -50); /* crossing zero down */
SDL_assert(v==35);
v=SDL_AtomicGet(&good);
SDL_assert(v==-15);
v=SDL_AtomicAdd(&good, 30); /* crossing zero up */
SDL_assert(v==-15);
v=SDL_AtomicGet(&good);
SDL_assert(v==15);
printf("Reset before count down test\n");
SDL_AtomicSet(&good, CountTo);
v=SDL_AtomicGet(&good);
SDL_assert(v==CountTo);
bad=CountTo;
SDL_assert(bad==CountTo);
printf("Counting down from %d, Expect %d remaining\n",CountTo,Expect);
runAdder();
v=SDL_AtomicGet(&good);
printf("Atomic %d Non-Atomic %d\n",v,bad);
SDL_assert(v==Expect);
SDL_assert(bad!=Expect);
}