/* This function checks the emulated CPU - GPU distance and may wake up the GPU,
* or block the CPU if required. It should be called by the CPU thread regularly.
* @ticks The gone emulated CPU time.
* @return A good time to call WaitForGpuThread() next.
*/
static int WaitForGpuThread(int ticks)
{
const SConfig& param = SConfig::GetInstance();
int old = s_sync_ticks.fetch_add(ticks);
int now = old + ticks;
// GPU is idle, so stop polling.
if (old >= 0 && s_gpu_mainloop.IsDone())
return -1;
// Wakeup GPU
if (old < param.iSyncGpuMinDistance && now >= param.iSyncGpuMinDistance)
RunGpu();
// If the GPU is still sleeping, wait for a longer time
if (now < param.iSyncGpuMinDistance)
return GPU_TIME_SLOT_SIZE + param.iSyncGpuMinDistance - now;
// Wait for GPU
if (now >= param.iSyncGpuMaxDistance)
s_sync_wakeup_event.Wait();
return GPU_TIME_SLOT_SIZE;
}
int Fifo_Update(int ticks)
{
const SConfig& param = SConfig::GetInstance();
if (ticks == 0)
{
FlushGpu();
return param.iSyncGpuMaxDistance;
}
// GPU is sleeping, so no need for synchronization
if (s_gpu_mainloop.IsDone() || g_use_deterministic_gpu_thread)
{
if (s_sync_ticks.load() < 0)
{
int old = s_sync_ticks.fetch_add(ticks);
if (old < param.iSyncGpuMinDistance && old + ticks >= param.iSyncGpuMinDistance)
RunGpu();
}
return param.iSyncGpuMaxDistance;
}
int old = s_sync_ticks.fetch_add(ticks);
if (old < param.iSyncGpuMinDistance && old + ticks >= param.iSyncGpuMinDistance)
RunGpu();
if (s_sync_ticks.load() >= param.iSyncGpuMaxDistance)
{
while (s_sync_ticks.load() > 0)
{
s_sync_wakeup_event.Wait();
}
}
return param.iSyncGpuMaxDistance - s_sync_ticks.load();
}