void ClientProxy::interrupt()
{
audio_track_cblk_t* cblk = mCblk;
if (!(android_atomic_or(CBLK_INTERRUPT, &cblk->mFlags) & CBLK_INTERRUPT)) {
(void) __futex_syscall3(&cblk->mFutex, mClientInServer ? FUTEX_WAKE_PRIVATE : FUTEX_WAKE,
1);
}
}
bool AudioTrackServerProxy::setStreamEndDone() {
bool old =
(android_atomic_or(CBLK_STREAM_END_DONE, &mCblk->mFlags) & CBLK_STREAM_END_DONE) != 0;
if (!old) {
(void) __futex_syscall3(&mCblk->mFutex, mClientInServer ? FUTEX_WAKE_PRIVATE : FUTEX_WAKE,
1);
}
return old;
}
void ClientProxy::binderDied()
{
audio_track_cblk_t* cblk = mCblk;
if (!(android_atomic_or(CBLK_INVALID, &cblk->mFlags) & CBLK_INVALID)) {
// it seems that a FUTEX_WAKE_PRIVATE will not wake a FUTEX_WAIT, even within same process
(void) __futex_syscall3(&cblk->mFutex, mClientInServer ? FUTEX_WAKE_PRIVATE : FUTEX_WAKE,
1);
}
}
void ServerProxy::releaseBuffer(Buffer* buffer)
{
LOG_ALWAYS_FATAL_IF(buffer == NULL);
size_t stepCount = buffer->mFrameCount;
if (stepCount == 0 || mIsShutdown) {
// prevent accidental re-use of buffer
buffer->mFrameCount = 0;
buffer->mRaw = NULL;
buffer->mNonContig = 0;
return;
}
LOG_ALWAYS_FATAL_IF(!(stepCount <= mUnreleased && mUnreleased <= mFrameCount));
mUnreleased -= stepCount;
audio_track_cblk_t* cblk = mCblk;
if (mIsOut) {
int32_t front = cblk->u.mStreaming.mFront;
android_atomic_release_store(stepCount + front, &cblk->u.mStreaming.mFront);
} else {
int32_t rear = cblk->u.mStreaming.mRear;
android_atomic_release_store(stepCount + rear, &cblk->u.mStreaming.mRear);
}
mCblk->mServer += stepCount;
size_t half = mFrameCount / 2;
if (half == 0) {
half = 1;
}
size_t minimum = cblk->mMinimum;
if (minimum == 0) {
minimum = mIsOut ? half : 1;
} else if (minimum > half) {
minimum = half;
}
// FIXME AudioRecord wakeup needs to be optimized; it currently wakes up client every time
if (!mIsOut || (mAvailToClient + stepCount >= minimum)) {
ALOGV("mAvailToClient=%u stepCount=%u minimum=%u", mAvailToClient, stepCount, minimum);
int32_t old = android_atomic_or(CBLK_FUTEX_WAKE, &cblk->mFutex);
if (!(old & CBLK_FUTEX_WAKE)) {
(void) __futex_syscall3(&cblk->mFutex,
mClientInServer ? FUTEX_WAKE_PRIVATE : FUTEX_WAKE, 1);
}
}
buffer->mFrameCount = 0;
buffer->mRaw = NULL;
buffer->mNonContig = 0;
}
int __futex_wake_ex(volatile void *ftx, int pshared, int val)
{
return __futex_syscall3(ftx, pshared ? FUTEX_WAKE : FUTEX_WAKE_PRIVATE, val);
}
status_t ServerProxy::obtainBuffer(Buffer* buffer, bool ackFlush)
{
LOG_ALWAYS_FATAL_IF(buffer == NULL || buffer->mFrameCount == 0);
if (mIsShutdown) {
goto no_init;
}
{
audio_track_cblk_t* cblk = mCblk;
// compute number of frames available to write (AudioTrack) or read (AudioRecord),
// or use previous cached value from framesReady(), with added barrier if it omits.
int32_t front;
int32_t rear;
// See notes on barriers at ClientProxy::obtainBuffer()
if (mIsOut) {
int32_t flush = cblk->u.mStreaming.mFlush;
rear = android_atomic_acquire_load(&cblk->u.mStreaming.mRear);
front = cblk->u.mStreaming.mFront;
if (flush != mFlush) {
mFlush = flush;
// effectively obtain then release whatever is in the buffer
android_atomic_release_store(rear, &cblk->u.mStreaming.mFront);
if (front != rear) {
int32_t old = android_atomic_or(CBLK_FUTEX_WAKE, &cblk->mFutex);
if (!(old & CBLK_FUTEX_WAKE)) {
(void) __futex_syscall3(&cblk->mFutex,
mClientInServer ? FUTEX_WAKE_PRIVATE : FUTEX_WAKE, 1);
}
}
front = rear;
}
} else {
front = android_atomic_acquire_load(&cblk->u.mStreaming.mFront);
rear = cblk->u.mStreaming.mRear;
}
ssize_t filled = rear - front;
// pipe should not already be overfull
if (!(0 <= filled && (size_t) filled <= mFrameCount)) {
ALOGE("Shared memory control block is corrupt (filled=%d); shutting down", filled);
mIsShutdown = true;
}
if (mIsShutdown) {
goto no_init;
}
// don't allow filling pipe beyond the nominal size
size_t availToServer;
if (mIsOut) {
availToServer = filled;
mAvailToClient = mFrameCount - filled;
} else {
availToServer = mFrameCount - filled;
mAvailToClient = filled;
}
// 'availToServer' may be non-contiguous, so return only the first contiguous chunk
size_t part1;
// Use modulo operator instead of and operator.
// x &= (y-1) returns the remainder if y is even
// Use modulo operator to generalize it for all values.
// This is needed for tunnel voip and tunnel encode usecases.
if (mIsOut) {
front %= mFrameCountP2;
part1 = mFrameCountP2 - front;
} else {
rear %= mFrameCountP2;
part1 = mFrameCountP2 - rear;
}
if (part1 > availToServer) {
part1 = availToServer;
}
size_t ask = buffer->mFrameCount;
if (part1 > ask) {
part1 = ask;
}
// is assignment redundant in some cases?
buffer->mFrameCount = part1;
buffer->mRaw = part1 > 0 ?
&((char *) mBuffers)[(mIsOut ? front : rear) * mFrameSize] : NULL;
buffer->mNonContig = availToServer - part1;
// After flush(), allow releaseBuffer() on a previously obtained buffer;
// see "Acknowledge any pending flush()" in audioflinger/Tracks.cpp.
if (!ackFlush) {
mUnreleased = part1;
}
return part1 > 0 ? NO_ERROR : WOULD_BLOCK;
}
no_init:
buffer->mFrameCount = 0;
buffer->mRaw = NULL;
buffer->mNonContig = 0;
mUnreleased = 0;
return NO_INIT;
}
