replicant-frameworks_native/include/gui/BufferQueue.h
Daniel Lam 9abe1ebc95 Fixed disconnect bug in SurfaceTexture
BufferQueue's disconnect could race with updateTexImage
where invalid buffers could be released.  Additionally
fixed similar bug with setBufferCount.  Tests were added
to stress the disconnect mechanism.

Change-Id: I9afa4c64f3e025984e8a9e8d924852a71d044716
2012-04-02 14:55:01 -07:00

484 lines
20 KiB
C++

/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_GUI_BUFFERQUEUE_H
#define ANDROID_GUI_BUFFERQUEUE_H
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <gui/IGraphicBufferAlloc.h>
#include <gui/ISurfaceTexture.h>
#include <ui/GraphicBuffer.h>
#include <utils/String8.h>
#include <utils/Vector.h>
#include <utils/threads.h>
namespace android {
// ----------------------------------------------------------------------------
class BufferQueue : public BnSurfaceTexture {
public:
enum { MIN_UNDEQUEUED_BUFFERS = 2 };
enum {
MIN_ASYNC_BUFFER_SLOTS = MIN_UNDEQUEUED_BUFFERS + 1,
MIN_SYNC_BUFFER_SLOTS = MIN_UNDEQUEUED_BUFFERS
};
enum { NUM_BUFFER_SLOTS = 32 };
enum { NO_CONNECTED_API = 0 };
enum { INVALID_BUFFER_SLOT = -1 };
enum { STALE_BUFFER_SLOT = 1 };
// ConsumerListener is the interface through which the BufferQueue notifies
// the consumer of events that the consumer may wish to react to. Because
// the consumer will generally have a mutex that is locked during calls from
// teh consumer to the BufferQueue, these calls from the BufferQueue to the
// consumer *MUST* be called only when the BufferQueue mutex is NOT locked.
struct ConsumerListener : public virtual RefBase {
// onFrameAvailable is called from queueBuffer each time an additional
// frame becomes available for consumption. This means that frames that
// are queued while in asynchronous mode only trigger the callback if no
// previous frames are pending. Frames queued while in synchronous mode
// always trigger the callback.
//
// This is called without any lock held and can be called concurrently
// by multiple threads.
virtual void onFrameAvailable() = 0;
// onBuffersReleased is called to notify the buffer consumer that the
// BufferQueue has released its references to one or more GraphicBuffers
// contained in its slots. The buffer consumer should then call
// BufferQueue::getReleasedBuffers to retrieve the list of buffers
//
// This is called without any lock held and can be called concurrently
// by multiple threads.
virtual void onBuffersReleased() = 0;
};
// ProxyConsumerListener is a ConsumerListener implementation that keeps a weak
// reference to the actual consumer object. It forwards all calls to that
// consumer object so long as it exists.
//
// This class exists to avoid having a circular reference between the
// BufferQueue object and the consumer object. The reason this can't be a weak
// reference in the BufferQueue class is because we're planning to expose the
// consumer side of a BufferQueue as a binder interface, which doesn't support
// weak references.
class ProxyConsumerListener : public BufferQueue::ConsumerListener {
public:
ProxyConsumerListener(const wp<BufferQueue::ConsumerListener>& consumerListener);
virtual ~ProxyConsumerListener();
virtual void onFrameAvailable();
virtual void onBuffersReleased();
private:
// mConsumerListener is a weak reference to the ConsumerListener. This is
// the raison d'etre of ProxyConsumerListener.
wp<BufferQueue::ConsumerListener> mConsumerListener;
};
// BufferQueue manages a pool of gralloc memory slots to be used
// by producers and consumers.
// allowSynchronousMode specifies whether or not synchronous mode can be
// enabled.
BufferQueue(bool allowSynchronousMode = true);
virtual ~BufferQueue();
virtual int query(int what, int* value);
// setBufferCount updates the number of available buffer slots. After
// calling this all buffer slots are both unallocated and owned by the
// BufferQueue object (i.e. they are not owned by the client).
virtual status_t setBufferCount(int bufferCount);
virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf);
// dequeueBuffer gets the next buffer slot index for the client to use. If a
// buffer slot is available then that slot index is written to the location
// pointed to by the buf argument and a status of OK is returned. If no
// slot is available then a status of -EBUSY is returned and buf is
// unmodified.
// The width and height parameters must be no greater than the minimum of
// GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv).
// An error due to invalid dimensions might not be reported until
// updateTexImage() is called.
virtual status_t dequeueBuffer(int *buf, uint32_t width, uint32_t height,
uint32_t format, uint32_t usage);
// queueBuffer returns a filled buffer to the BufferQueue. In addition, a
// timestamp must be provided for the buffer. The timestamp is in
// nanoseconds, and must be monotonically increasing. Its other semantics
// (zero point, etc) are client-dependent and should be documented by the
// client.
virtual status_t queueBuffer(int buf, int64_t timestamp,
const Rect& crop, int scalingMode, uint32_t transform,
uint32_t* outWidth, uint32_t* outHeight, uint32_t* outTransform);
virtual void cancelBuffer(int buf);
// setSynchronousMode set whether dequeueBuffer is synchronous or
// asynchronous. In synchronous mode, dequeueBuffer blocks until
// a buffer is available, the currently bound buffer can be dequeued and
// queued buffers will be retired in order.
// The default mode is asynchronous.
virtual status_t setSynchronousMode(bool enabled);
// connect attempts to connect a producer client API to the BufferQueue.
// This must be called before any other ISurfaceTexture methods are called
// except for getAllocator.
//
// This method will fail if the connect was previously called on the
// BufferQueue and no corresponding disconnect call was made.
virtual status_t connect(int api,
uint32_t* outWidth, uint32_t* outHeight, uint32_t* outTransform);
// disconnect attempts to disconnect a producer client API from the
// BufferQueue. Calling this method will cause any subsequent calls to other
// ISurfaceTexture methods to fail except for getAllocator and connect.
// Successfully calling connect after this will allow the other methods to
// succeed again.
//
// This method will fail if the the BufferQueue is not currently
// connected to the specified client API.
virtual status_t disconnect(int api);
// dump our state in a String
virtual void dump(String8& result) const;
virtual void dump(String8& result, const char* prefix, char* buffer, size_t SIZE) const;
// public facing structure for BufferSlot
struct BufferItem {
BufferItem()
:
mTransform(0),
mScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
mTimestamp(0),
mFrameNumber(0),
mBuf(INVALID_BUFFER_SLOT) {
mCrop.makeInvalid();
}
// mGraphicBuffer points to the buffer allocated for this slot or is NULL
// if no buffer has been allocated.
sp<GraphicBuffer> mGraphicBuffer;
// mCrop is the current crop rectangle for this buffer slot.
Rect mCrop;
// mTransform is the current transform flags for this buffer slot.
uint32_t mTransform;
// mScalingMode is the current scaling mode for this buffer slot.
uint32_t mScalingMode;
// mTimestamp is the current timestamp for this buffer slot. This gets
// to set by queueBuffer each time this slot is queued.
int64_t mTimestamp;
// mFrameNumber is the number of the queued frame for this slot.
uint64_t mFrameNumber;
// buf is the slot index of this buffer
int mBuf;
};
// The following public functions is the consumer facing interface
// acquireBuffer attempts to acquire ownership of the next pending buffer in
// the BufferQueue. If no buffer is pending then it returns -EINVAL. If a
// buffer is successfully acquired, the information about the buffer is
// returned in BufferItem. If the buffer returned had previously been
// acquired then the BufferItem::mGraphicBuffer field of buffer is set to
// NULL and it is assumed that the consumer still holds a reference to the
// buffer.
status_t acquireBuffer(BufferItem *buffer);
// releaseBuffer releases a buffer slot from the consumer back to the
// BufferQueue pending a fence sync.
//
// Note that the dependencies on EGL will be removed once we switch to using
// the Android HW Sync HAL.
status_t releaseBuffer(int buf, EGLDisplay display, EGLSyncKHR fence);
// consumerConnect connects a consumer to the BufferQueue. Only one
// consumer may be connected, and when that consumer disconnects the
// BufferQueue is placed into the "abandoned" state, causing most
// interactions with the BufferQueue by the producer to fail.
status_t consumerConnect(const sp<ConsumerListener>& consumer);
// consumerDisconnect disconnects a consumer from the BufferQueue. All
// buffers will be freed and the BufferQueue is placed in the "abandoned"
// state, causing most interactions with the BufferQueue by the producer to
// fail.
status_t consumerDisconnect();
// getReleasedBuffers sets the value pointed to by slotMask to a bit mask
// indicating which buffer slots the have been released by the BufferQueue
// but have not yet been released by the consumer.
status_t getReleasedBuffers(uint32_t* slotMask);
// setDefaultBufferSize is used to set the size of buffers returned by
// requestBuffers when a with and height of zero is requested.
status_t setDefaultBufferSize(uint32_t w, uint32_t h);
// setBufferCountServer set the buffer count. If the client has requested
// a buffer count using setBufferCount, the server-buffer count will
// take effect once the client sets the count back to zero.
status_t setBufferCountServer(int bufferCount);
// isSynchronousMode returns whether the SurfaceTexture is currently in
// synchronous mode.
bool isSynchronousMode() const;
// setConsumerName sets the name used in logging
void setConsumerName(const String8& name);
// setDefaultBufferFormat allows the BufferQueue to create
// GraphicBuffers of a defaultFormat if no format is specified
// in dequeueBuffer
status_t setDefaultBufferFormat(uint32_t defaultFormat);
// setConsumerUsageBits will turn on additional usage bits for dequeueBuffer
status_t setConsumerUsageBits(uint32_t usage);
// setTransformHint bakes in rotation to buffers so overlays can be used
status_t setTransformHint(uint32_t hint);
private:
// freeBufferLocked frees the resources (both GraphicBuffer and EGLImage)
// for the given slot.
void freeBufferLocked(int index);
// freeAllBuffersLocked frees the resources (both GraphicBuffer and
// EGLImage) for all slots.
void freeAllBuffersLocked();
// freeAllBuffersExceptHeadLocked frees the resources (both GraphicBuffer
// and EGLImage) for all slots except the head of mQueue
void freeAllBuffersExceptHeadLocked();
// drainQueueLocked drains the buffer queue if we're in synchronous mode
// returns immediately otherwise. It returns NO_INIT if the BufferQueue
// became abandoned or disconnected during this call.
status_t drainQueueLocked();
// drainQueueAndFreeBuffersLocked drains the buffer queue if we're in
// synchronous mode and free all buffers. In asynchronous mode, all buffers
// are freed except the current buffer.
status_t drainQueueAndFreeBuffersLocked();
status_t setBufferCountServerLocked(int bufferCount);
struct BufferSlot {
BufferSlot()
: mEglDisplay(EGL_NO_DISPLAY),
mBufferState(BufferSlot::FREE),
mRequestBufferCalled(false),
mTransform(0),
mScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
mTimestamp(0),
mFrameNumber(0),
mFence(EGL_NO_SYNC_KHR),
mAcquireCalled(false),
mNeedsCleanupOnRelease(false) {
mCrop.makeInvalid();
}
// mGraphicBuffer points to the buffer allocated for this slot or is NULL
// if no buffer has been allocated.
sp<GraphicBuffer> mGraphicBuffer;
// mEglDisplay is the EGLDisplay used to create mEglImage.
EGLDisplay mEglDisplay;
// BufferState represents the different states in which a buffer slot
// can be.
enum BufferState {
// FREE indicates that the buffer is not currently being used and
// will not be used in the future until it gets dequeued and
// subsequently queued by the client.
// aka "owned by BufferQueue, ready to be dequeued"
FREE = 0,
// DEQUEUED indicates that the buffer has been dequeued by the
// client, but has not yet been queued or canceled. The buffer is
// considered 'owned' by the client, and the server should not use
// it for anything.
//
// Note that when in synchronous-mode (mSynchronousMode == true),
// the buffer that's currently attached to the texture may be
// dequeued by the client. That means that the current buffer can
// be in either the DEQUEUED or QUEUED state. In asynchronous mode,
// however, the current buffer is always in the QUEUED state.
// aka "owned by producer, ready to be queued"
DEQUEUED = 1,
// QUEUED indicates that the buffer has been queued by the client,
// and has not since been made available for the client to dequeue.
// Attaching the buffer to the texture does NOT transition the
// buffer away from the QUEUED state. However, in Synchronous mode
// the current buffer may be dequeued by the client under some
// circumstances. See the note about the current buffer in the
// documentation for DEQUEUED.
// aka "owned by BufferQueue, ready to be acquired"
QUEUED = 2,
// aka "owned by consumer, ready to be released"
ACQUIRED = 3
};
// mBufferState is the current state of this buffer slot.
BufferState mBufferState;
// mRequestBufferCalled is used for validating that the client did
// call requestBuffer() when told to do so. Technically this is not
// needed but useful for debugging and catching client bugs.
bool mRequestBufferCalled;
// mCrop is the current crop rectangle for this buffer slot.
Rect mCrop;
// mTransform is the current transform flags for this buffer slot.
uint32_t mTransform;
// mScalingMode is the current scaling mode for this buffer slot.
uint32_t mScalingMode;
// mTimestamp is the current timestamp for this buffer slot. This gets
// to set by queueBuffer each time this slot is queued.
int64_t mTimestamp;
// mFrameNumber is the number of the queued frame for this slot.
uint64_t mFrameNumber;
// mFence is the EGL sync object that must signal before the buffer
// associated with this buffer slot may be dequeued. It is initialized
// to EGL_NO_SYNC_KHR when the buffer is created and (optionally, based
// on a compile-time option) set to a new sync object in updateTexImage.
EGLSyncKHR mFence;
// Indicates whether this buffer has been seen by a consumer yet
bool mAcquireCalled;
// Indicates whether this buffer needs to be cleaned up by consumer
bool mNeedsCleanupOnRelease;
};
// mSlots is the array of buffer slots that must be mirrored on the client
// side. This allows buffer ownership to be transferred between the client
// and server without sending a GraphicBuffer over binder. The entire array
// is initialized to NULL at construction time, and buffers are allocated
// for a slot when requestBuffer is called with that slot's index.
BufferSlot mSlots[NUM_BUFFER_SLOTS];
// mDefaultWidth holds the default width of allocated buffers. It is used
// in requestBuffers() if a width and height of zero is specified.
uint32_t mDefaultWidth;
// mDefaultHeight holds the default height of allocated buffers. It is used
// in requestBuffers() if a width and height of zero is specified.
uint32_t mDefaultHeight;
// mPixelFormat holds the pixel format of allocated buffers. It is used
// in requestBuffers() if a format of zero is specified.
uint32_t mPixelFormat;
// mBufferCount is the number of buffer slots that the client and server
// must maintain. It defaults to MIN_ASYNC_BUFFER_SLOTS and can be changed
// by calling setBufferCount or setBufferCountServer
int mBufferCount;
// mClientBufferCount is the number of buffer slots requested by the client.
// The default is zero, which means the client doesn't care how many buffers
// there is.
int mClientBufferCount;
// mServerBufferCount buffer count requested by the server-side
int mServerBufferCount;
// mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to
// allocate new GraphicBuffer objects.
sp<IGraphicBufferAlloc> mGraphicBufferAlloc;
// mConsumerListener is used to notify the connected consumer of
// asynchronous events that it may wish to react to. It is initially set
// to NULL and is written by consumerConnect and consumerDisconnect.
sp<ConsumerListener> mConsumerListener;
// mSynchronousMode whether we're in synchronous mode or not
bool mSynchronousMode;
// mAllowSynchronousMode whether we allow synchronous mode or not
const bool mAllowSynchronousMode;
// mConnectedApi indicates the API that is currently connected to this
// BufferQueue. It defaults to NO_CONNECTED_API (= 0), and gets updated
// by the connect and disconnect methods.
int mConnectedApi;
// mDequeueCondition condition used for dequeueBuffer in synchronous mode
mutable Condition mDequeueCondition;
// mQueue is a FIFO of queued buffers used in synchronous mode
typedef Vector<int> Fifo;
Fifo mQueue;
// mAbandoned indicates that the BufferQueue will no longer be used to
// consume images buffers pushed to it using the ISurfaceTexture interface.
// It is initialized to false, and set to true in the abandon method. A
// BufferQueue that has been abandoned will return the NO_INIT error from
// all ISurfaceTexture methods capable of returning an error.
bool mAbandoned;
// mName is a string used to identify the BufferQueue in log messages.
// It is set by the setName method.
String8 mConsumerName;
// mMutex is the mutex used to prevent concurrent access to the member
// variables of BufferQueue objects. It must be locked whenever the
// member variables are accessed.
mutable Mutex mMutex;
// mFrameCounter is the free running counter, incremented for every buffer queued
// with the surface Texture.
uint64_t mFrameCounter;
// mBufferHasBeenQueued is true once a buffer has been queued. It is reset
// by changing the buffer count.
bool mBufferHasBeenQueued;
// mDefaultBufferFormat can be set so it will override
// the buffer format when it isn't specified in dequeueBuffer
uint32_t mDefaultBufferFormat;
// mConsumerUsageBits contains flags the consumer wants for GraphicBuffers
uint32_t mConsumerUsageBits;
// mTransformHint is used to optimize for screen rotations
uint32_t mTransformHint;
};
// ----------------------------------------------------------------------------
}; // namespace android
#endif // ANDROID_GUI_BUFFERQUEUE_H