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audio: Don't trust audio drivers to drain pending audio.

This tends to be a frequent spot where drivers hang, and the waits were
often unreliable in any case.

Instead, our audio thread now alerts the driver that we're done streaming audio
(which currently XAudio2 uses to alert the system not to warn about the
impending underflow) and then SDL_Delay()'s for a duration that's reasonable
to drain the DMA buffers before closing the device.
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icculus committed Oct 7, 2016
1 parent 551cdc8 commit f6a280ab7f24cb40f41f78b71d1968a26bdcb2ed
@@ -191,11 +191,6 @@ SDL_AudioGetDeviceBuf_Default(_THIS)
return NULL;
}

static void
SDL_AudioWaitDone_Default(_THIS)
{ /* no-op. */
}

static int
SDL_AudioCaptureFromDevice_Default(_THIS, void *buffer, int buflen)
{
@@ -207,6 +202,11 @@ SDL_AudioFlushCapture_Default(_THIS)
{ /* no-op. */
}

static void
SDL_AudioPrepareToClose_Default(_THIS)
{ /* no-op. */
}

static void
SDL_AudioCloseDevice_Default(_THIS)
{ /* no-op. */
@@ -292,9 +292,9 @@ finish_audio_entry_points_init(void)
FILL_STUB(PlayDevice);
FILL_STUB(GetPendingBytes);
FILL_STUB(GetDeviceBuf);
FILL_STUB(WaitDone);
FILL_STUB(CaptureFromDevice);
FILL_STUB(FlushCapture);
FILL_STUB(PrepareToClose);
FILL_STUB(CloseDevice);
FILL_STUB(LockDevice);
FILL_STUB(UnlockDevice);
@@ -715,6 +715,9 @@ SDL_FinalizeAudioDevice(SDL_AudioDevice *device)
return;
}

SDL_AtomicSet(&device->shutdown, 1); /* just in case. */
SDL_AtomicSet(&device->enabled, 0);

/* lock/unlock here so we don't race if the audio thread saw the shutdown
var without locking, and the thread that requested shutdown is now
trying to unlock the mutex while we destroy it. Threading is hard. */
@@ -811,9 +814,10 @@ SDL_RunAudio(void *devicep)
}
}

current_audio.impl.PrepareToClose(device);

/* Wait for the audio to drain. */
/* !!! FIXME: can we rename this WaitDrain? */
current_audio.impl.WaitDone(device);
SDL_Delay(((device->spec.samples * 1000) / device->spec.freq) * 2);

SDL_FinalizeAudioDevice(device);

@@ -1153,7 +1157,7 @@ close_audio_device(SDL_AudioDevice * device)

if (!device->iscapture) {
const SDL_AudioSpec *spec = &device->spec;
delay = ((spec.samples * 1000) / spec.freq) * 2;
delay = ((spec->samples * 1000) / spec->freq) * 2;
}

/* Lock to make sure an audio callback doesn't fire after we return.
@@ -79,9 +79,9 @@ typedef struct SDL_AudioDriverImpl
void (*PlayDevice) (_THIS);
int (*GetPendingBytes) (_THIS);
Uint8 *(*GetDeviceBuf) (_THIS);
void (*WaitDone) (_THIS);
int (*CaptureFromDevice) (_THIS, void *buffer, int buflen);
void (*FlushCapture) (_THIS);
void (*PrepareToClose) (_THIS); /**< Called between run and draining wait for playback devices */
void (*CloseDevice) (_THIS);
void (*LockDevice) (_THIS);
void (*UnlockDevice) (_THIS);
@@ -185,13 +185,6 @@ ARTS_PlayDevice(_THIS)
#endif
}

static void
ARTS_WaitDone(_THIS)
{
/* !!! FIXME: camp here until buffer drains... SDL_Delay(???); */
}


static Uint8 *
ARTS_GetDeviceBuf(_THIS)
{
@@ -356,7 +349,6 @@ ARTS_Init(SDL_AudioDriverImpl * impl)
impl->WaitDevice = ARTS_WaitDevice;
impl->GetDeviceBuf = ARTS_GetDeviceBuf;
impl->CloseDevice = ARTS_CloseDevice;
impl->WaitDone = ARTS_WaitDone;
impl->Deinitialize = ARTS_Deinitialize;
impl->OnlyHasDefaultOutputDevice = 1;

@@ -307,22 +307,6 @@ DSOUND_GetDeviceBuf(_THIS)
return (this->hidden->locked_buf);
}

static void
DSOUND_WaitDone(_THIS)
{
Uint8 *stream = DSOUND_GetDeviceBuf(this);

/* Wait for the playing chunk to finish */
if (stream != NULL) {
SDL_memset(stream, this->spec.silence, this->spec.size);
DSOUND_PlayDevice(this);
}
DSOUND_WaitDevice(this);

/* Stop the looping sound buffer */
IDirectSoundBuffer_Stop(this->hidden->mixbuf);
}

static int
DSOUND_CaptureFromDevice(_THIS, void *buffer, int buflen)
{
@@ -600,7 +584,6 @@ DSOUND_Init(SDL_AudioDriverImpl * impl)
impl->OpenDevice = DSOUND_OpenDevice;
impl->PlayDevice = DSOUND_PlayDevice;
impl->WaitDevice = DSOUND_WaitDevice;
impl->WaitDone = DSOUND_WaitDone;
impl->GetDeviceBuf = DSOUND_GetDeviceBuf;
impl->CaptureFromDevice = DSOUND_CaptureFromDevice;
impl->FlushCapture = DSOUND_FlushCapture;
@@ -151,13 +151,6 @@ SDL_FS_PlayDevice(_THIS)
#endif
}

static void
SDL_FS_WaitDone(_THIS)
{
this->hidden->stream->Wait(this->hidden->stream,
this->hidden->mixsamples * FUSION_BUFFERS);
}


static Uint8 *
SDL_FS_GetDeviceBuf(_THIS)
@@ -319,7 +312,6 @@ SDL_FS_Init(SDL_AudioDriverImpl * impl)
impl->WaitDevice = SDL_FS_WaitDevice;
impl->GetDeviceBuf = SDL_FS_GetDeviceBuf;
impl->CloseDevice = SDL_FS_CloseDevice;
impl->WaitDone = SDL_FS_WaitDone;
impl->Deinitialize = SDL_FS_Deinitialize;
impl->OnlyHasDefaultOutputDevice = 1;

@@ -152,7 +152,6 @@ PSPAUDIO_Init(SDL_AudioDriverImpl * impl)
impl->PlayDevice = PSPAUDIO_PlayDevice;
impl->WaitDevice = PSPAUDIO_WaitDevice;
impl->GetDeviceBuf = PSPAUDIO_GetDeviceBuf;
impl->WaitDone = PSPAUDIO_WaitDevice;
impl->CloseDevice = PSPAUDIO_CloseDevice;
impl->ThreadInit = PSPAUDIO_ThreadInit;

@@ -368,28 +368,6 @@ PULSEAUDIO_PlayDevice(_THIS)
}
}

static void
PULSEAUDIO_WaitDone(_THIS)
{
if (SDL_AtomicGet(&this->enabled)) {
struct SDL_PrivateAudioData *h = this->hidden;
pa_operation *o = PULSEAUDIO_pa_stream_drain(h->stream, stream_operation_complete_no_op, NULL);
if (o) {
while (PULSEAUDIO_pa_operation_get_state(o) != PA_OPERATION_DONE) {
if (PULSEAUDIO_pa_context_get_state(h->context) != PA_CONTEXT_READY ||
PULSEAUDIO_pa_stream_get_state(h->stream) != PA_STREAM_READY ||
PULSEAUDIO_pa_mainloop_iterate(h->mainloop, 1, NULL) < 0) {
PULSEAUDIO_pa_operation_cancel(o);
break;
}
}
PULSEAUDIO_pa_operation_unref(o);
}
}
}



static Uint8 *
PULSEAUDIO_GetDeviceBuf(_THIS)
{
@@ -776,7 +754,6 @@ PULSEAUDIO_Init(SDL_AudioDriverImpl * impl)
impl->WaitDevice = PULSEAUDIO_WaitDevice;
impl->GetDeviceBuf = PULSEAUDIO_GetDeviceBuf;
impl->CloseDevice = PULSEAUDIO_CloseDevice;
impl->WaitDone = PULSEAUDIO_WaitDone;
impl->Deinitialize = PULSEAUDIO_Deinitialize;
impl->CaptureFromDevice = PULSEAUDIO_CaptureFromDevice;
impl->FlushCapture = PULSEAUDIO_FlushCapture;
@@ -708,24 +708,6 @@ QSA_DetectDevices(void)
}
}

static void
QSA_WaitDone(_THIS)
{
if (!this->hidden->iscapture) {
if (this->hidden->audio_handle != NULL) {
/* Wait till last fragment is played and stop channel */
snd_pcm_plugin_flush(this->hidden->audio_handle,
SND_PCM_CHANNEL_PLAYBACK);
}
} else {
if (this->hidden->audio_handle != NULL) {
/* Discard all unread data and stop channel */
snd_pcm_plugin_flush(this->hidden->audio_handle,
SND_PCM_CHANNEL_CAPTURE);
}
}
}

static void
QSA_Deinitialize(void)
{
@@ -759,7 +741,6 @@ QSA_Init(SDL_AudioDriverImpl * impl)
impl->PlayDevice = QSA_PlayDevice;
impl->GetDeviceBuf = QSA_GetDeviceBuf;
impl->CloseDevice = QSA_CloseDevice;
impl->WaitDone = QSA_WaitDone;
impl->Deinitialize = QSA_Deinitialize;
impl->LockDevice = NULL;
impl->UnlockDevice = NULL;
@@ -170,16 +170,11 @@ SNDIO_GetDeviceBuf(_THIS)
return this->hidden->mixbuf;
}

static void
SNDIO_WaitDone(_THIS)
{
SNDIO_sio_stop(this->hidden->dev);
}

static void
SNDIO_CloseDevice(_THIS)
{
if ( this->hidden->dev != NULL ) {
SNDIO_sio_stop(this->hidden->dev);
SNDIO_sio_close(this->hidden->dev);
}
SDL_free(this->hidden->mixbuf);
@@ -304,7 +299,6 @@ SNDIO_Init(SDL_AudioDriverImpl * impl)
impl->WaitDevice = SNDIO_WaitDevice;
impl->PlayDevice = SNDIO_PlayDevice;
impl->GetDeviceBuf = SNDIO_GetDeviceBuf;
impl->WaitDone = SNDIO_WaitDone;
impl->CloseDevice = SNDIO_CloseDevice;
impl->Deinitialize = SNDIO_Deinitialize;
impl->OnlyHasDefaultOutputDevice = 1; /* !!! FIXME: sndio can handle multiple devices. */
@@ -135,24 +135,6 @@ WINMM_PlayDevice(_THIS)
this->hidden->next_buffer = (this->hidden->next_buffer + 1) % NUM_BUFFERS;
}

static void
WINMM_WaitDone(_THIS)
{
int i, left;

do {
left = NUM_BUFFERS;
for (i = 0; i < NUM_BUFFERS; ++i) {
if (this->hidden->wavebuf[i].dwFlags & WHDR_DONE) {
--left;
}
}
if (left > 0) {
SDL_Delay(100);
}
} while (left > 0);
}

static int
WINMM_CaptureFromDevice(_THIS, void *buffer, int buflen)
{
@@ -422,7 +404,6 @@ WINMM_Init(SDL_AudioDriverImpl * impl)
impl->OpenDevice = WINMM_OpenDevice;
impl->PlayDevice = WINMM_PlayDevice;
impl->WaitDevice = WINMM_WaitDevice;
impl->WaitDone = WINMM_WaitDone;
impl->GetDeviceBuf = WINMM_GetDeviceBuf;
impl->CaptureFromDevice = WINMM_CaptureFromDevice;
impl->FlushCapture = WINMM_FlushCapture;
@@ -232,28 +232,14 @@ XAUDIO2_WaitDevice(_THIS)
}

static void
XAUDIO2_WaitDone(_THIS)
XAUDIO2_PrepareToClose(_THIS)
{
IXAudio2SourceVoice *source = this->hidden->source;
XAUDIO2_VOICE_STATE state;
SDL_assert(!SDL_AtomicGet(&this->enabled)); /* flag that stops playing. */
IXAudio2SourceVoice_Discontinuity(source);
#if SDL_XAUDIO2_WIN8
IXAudio2SourceVoice_GetState(source, &state, XAUDIO2_VOICE_NOSAMPLESPLAYED);
#else
IXAudio2SourceVoice_GetState(source, &state);
#endif
while (state.BuffersQueued > 0) {
SDL_SemWait(this->hidden->semaphore);
#if SDL_XAUDIO2_WIN8
IXAudio2SourceVoice_GetState(source, &state, XAUDIO2_VOICE_NOSAMPLESPLAYED);
#else
IXAudio2SourceVoice_GetState(source, &state);
#endif
if (source) {
IXAudio2SourceVoice_Discontinuity(source);
}
}


static void
XAUDIO2_CloseDevice(_THIS)
{
@@ -489,7 +475,7 @@ XAUDIO2_Init(SDL_AudioDriverImpl * impl)
impl->OpenDevice = XAUDIO2_OpenDevice;
impl->PlayDevice = XAUDIO2_PlayDevice;
impl->WaitDevice = XAUDIO2_WaitDevice;
impl->WaitDone = XAUDIO2_WaitDone;
impl->PrepareToClose = XAUDIO2_PrepareToClose;
impl->GetDeviceBuf = XAUDIO2_GetDeviceBuf;
impl->CloseDevice = XAUDIO2_CloseDevice;
impl->Deinitialize = XAUDIO2_Deinitialize;

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