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#include <private/dvr/consumer_buffer.h>
using android::pdx::LocalChannelHandle;
using android::pdx::LocalHandle;
using android::pdx::Status;
namespace android {
namespace dvr {
ConsumerBuffer::ConsumerBuffer(LocalChannelHandle channel)
: BASE(std::move(channel)) {
const int ret = ImportBuffer();
if (ret < 0) {
ALOGE("ConsumerBuffer::ConsumerBuffer: Failed to import buffer: %s",
strerror(-ret));
Close(ret);
}
}
std::unique_ptr<ConsumerBuffer> ConsumerBuffer::Import(
LocalChannelHandle channel) {
ATRACE_NAME("ConsumerBuffer::Import");
ALOGD_IF(TRACE, "ConsumerBuffer::Import: channel=%d", channel.value());
return ConsumerBuffer::Create(std::move(channel));
}
std::unique_ptr<ConsumerBuffer> ConsumerBuffer::Import(
Status<LocalChannelHandle> status) {
return Import(status ? status.take()
: LocalChannelHandle{nullptr, -status.error()});
}
int ConsumerBuffer::LocalAcquire(DvrNativeBufferMetadata* out_meta,
LocalHandle* out_fence) {
if (!out_meta)
return -EINVAL;
// The buffer can be acquired iff the buffer state for this client is posted.
uint32_t current_buffer_state =
buffer_state_->load(std::memory_order_acquire);
if (!BufferHubDefs::isClientPosted(current_buffer_state,
client_state_mask())) {
ALOGE(
"%s: Failed to acquire the buffer. The buffer is not posted, id=%d "
"state=%" PRIx32 " client_state_mask=%" PRIx32 ".",
__FUNCTION__, id(), current_buffer_state, client_state_mask());
return -EBUSY;
}
// Change the buffer state for this consumer from posted to acquired.
uint32_t updated_buffer_state = current_buffer_state ^ client_state_mask();
while (!buffer_state_->compare_exchange_weak(
current_buffer_state, updated_buffer_state, std::memory_order_acq_rel,
std::memory_order_acquire)) {
if (!BufferHubDefs::isClientPosted(current_buffer_state,
client_state_mask())) {
ALOGE(
"%s: Failed to acquire the buffer. The buffer is no longer posted, "
"id=%d state=%" PRIx32 " client_state_mask=%" PRIx32 ".",
__FUNCTION__, id(), current_buffer_state, client_state_mask());
return -EBUSY;
}
// The failure of compare_exchange_weak updates current_buffer_state.
updated_buffer_state = current_buffer_state ^ client_state_mask();
}
// Copy the canonical metadata.
void* metadata_ptr = reinterpret_cast<void*>(&metadata_header_->metadata);
memcpy(out_meta, metadata_ptr, sizeof(DvrNativeBufferMetadata));
// Fill in the user_metadata_ptr in address space of the local process.
if (out_meta->user_metadata_size) {
out_meta->user_metadata_ptr =
reinterpret_cast<uint64_t>(user_metadata_ptr_);
} else {
out_meta->user_metadata_ptr = 0;
}
uint32_t fence_state = fence_state_->load(std::memory_order_acquire);
// If there is an acquire fence from producer, we need to return it.
// The producer state bit mask is kFirstClientBitMask for now.
if (fence_state & BufferHubDefs::kFirstClientBitMask) {
*out_fence = shared_acquire_fence_.Duplicate();
}
return 0;
}
int ConsumerBuffer::Acquire(LocalHandle* ready_fence) {
return Acquire(ready_fence, nullptr, 0);
}
int ConsumerBuffer::Acquire(LocalHandle* ready_fence, void* meta,
size_t user_metadata_size) {
ATRACE_NAME("ConsumerBuffer::Acquire");
if (const int error = CheckMetadata(user_metadata_size))
return error;
DvrNativeBufferMetadata canonical_meta;
if (const int error = LocalAcquire(&canonical_meta, ready_fence))
return error;
if (meta && user_metadata_size) {
void* metadata_src =
reinterpret_cast<void*>(canonical_meta.user_metadata_ptr);
if (metadata_src) {
memcpy(meta, metadata_src, user_metadata_size);
} else {
ALOGW("ConsumerBuffer::Acquire: no user-defined metadata.");
}
}
auto status = InvokeRemoteMethod<BufferHubRPC::ConsumerAcquire>();
if (!status)
return -status.error();
return 0;
}
int ConsumerBuffer::AcquireAsync(DvrNativeBufferMetadata* out_meta,
LocalHandle* out_fence) {
ATRACE_NAME("ConsumerBuffer::AcquireAsync");
if (const int error = LocalAcquire(out_meta, out_fence))
return error;
auto status = SendImpulse(BufferHubRPC::ConsumerAcquire::Opcode);
if (!status)
return -status.error();
return 0;
}
int ConsumerBuffer::LocalRelease(const DvrNativeBufferMetadata* meta,
const LocalHandle& release_fence) {
if (const int error = CheckMetadata(meta->user_metadata_size))
return error;
// Set the buffer state of this client to released if it is not already in
// released state.
uint32_t current_buffer_state =
buffer_state_->load(std::memory_order_acquire);
if (BufferHubDefs::isClientReleased(current_buffer_state,
client_state_mask())) {
return 0;
}
uint32_t updated_buffer_state = current_buffer_state & (~client_state_mask());
while (!buffer_state_->compare_exchange_weak(
current_buffer_state, updated_buffer_state, std::memory_order_acq_rel,
std::memory_order_acquire)) {
// The failure of compare_exchange_weak updates current_buffer_state.
updated_buffer_state = current_buffer_state & (~client_state_mask());
}
// On release, only the user requested metadata is copied back into the shared
// memory for metadata. Since there are multiple consumers, it doesn't make
// sense to send the canonical metadata back to the producer. However, one of
// the consumer can still choose to write up to user_metadata_size bytes of
// data into user_metadata_ptr.
if (meta->user_metadata_ptr && meta->user_metadata_size) {
void* metadata_src = reinterpret_cast<void*>(meta->user_metadata_ptr);
memcpy(user_metadata_ptr_, metadata_src, meta->user_metadata_size);
}
// Send out the release fence through the shared epoll fd. Note that during
// releasing the producer is not expected to be polling on the fence.
if (const int error = UpdateSharedFence(release_fence, shared_release_fence_))
return error;
return 0;
}
int ConsumerBuffer::Release(const LocalHandle& release_fence) {
ATRACE_NAME("ConsumerBuffer::Release");
DvrNativeBufferMetadata meta;
if (const int error = LocalRelease(&meta, release_fence))
return error;
return ReturnStatusOrError(InvokeRemoteMethod<BufferHubRPC::ConsumerRelease>(
BorrowedFence(release_fence.Borrow())));
}
int ConsumerBuffer::ReleaseAsync() {
DvrNativeBufferMetadata meta;
return ReleaseAsync(&meta, LocalHandle());
}
int ConsumerBuffer::ReleaseAsync(const DvrNativeBufferMetadata* meta,
const LocalHandle& release_fence) {
ATRACE_NAME("ConsumerBuffer::ReleaseAsync");
if (const int error = LocalRelease(meta, release_fence))
return error;
return ReturnStatusOrError(
SendImpulse(BufferHubRPC::ConsumerRelease::Opcode));
}
int ConsumerBuffer::Discard() { return Release(LocalHandle()); }
} // namespace dvr
} // namespace android
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