Camera: Avoid dequeue too many buffers from buffer queue
The PreviewFrameSpacer could defer 1 or 2 buffers to reduce jitter.
And we update the handout buffer count at the time of queuing to
the preview frame spacer, not at the time of queuing to the buffer
queue.
This results in accounting mismatch where the framework could allow
the HAL to dequeue more buffers than supported.
The fix is to track the framework cached buffer count in addition to the
handout buffer count.
Test: Camera CTS, vendor testing, observe logcat with GoogleCamera
Bug: 242674531
Change-Id: I579ae7465b59f5bd9e12dfda332998b401793eb4
diff --git a/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp b/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp
index add1483..f594f84 100644
--- a/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp
+++ b/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp
@@ -41,8 +41,10 @@
physicalCameraId, sensorPixelModesUsed, setId, isMultiResolution,
dynamicRangeProfile, streamUseCase, deviceTimeBaseIsRealtime, timestampBase),
mTotalBufferCount(0),
+ mMaxCachedBufferCount(0),
mHandoutTotalBufferCount(0),
mHandoutOutputBufferCount(0),
+ mCachedOutputBufferCount(0),
mFrameCount(0),
mLastTimestamp(0) {
@@ -95,8 +97,8 @@
lines.appendFormat(" Timestamp base: %d\n", getTimestampBase());
lines.appendFormat(" Frames produced: %d, last timestamp: %" PRId64 " ns\n",
mFrameCount, mLastTimestamp);
- lines.appendFormat(" Total buffers: %zu, currently dequeued: %zu\n",
- mTotalBufferCount, mHandoutTotalBufferCount);
+ lines.appendFormat(" Total buffers: %zu, currently dequeued: %zu, currently cached: %zu\n",
+ mTotalBufferCount, mHandoutTotalBufferCount, mCachedOutputBufferCount);
write(fd, lines.string(), lines.size());
Camera3Stream::dump(fd, args);
@@ -135,6 +137,14 @@
return (mHandoutTotalBufferCount - mHandoutOutputBufferCount);
}
+size_t Camera3IOStreamBase::getCachedOutputBufferCountLocked() const {
+ return mCachedOutputBufferCount;
+}
+
+size_t Camera3IOStreamBase::getMaxCachedOutputBuffersLocked() const {
+ return mMaxCachedBufferCount;
+}
+
status_t Camera3IOStreamBase::disconnectLocked() {
switch (mState) {
case STATE_IN_RECONFIG:
diff --git a/services/camera/libcameraservice/device3/Camera3IOStreamBase.h b/services/camera/libcameraservice/device3/Camera3IOStreamBase.h
index f389d53..ca1f238 100644
--- a/services/camera/libcameraservice/device3/Camera3IOStreamBase.h
+++ b/services/camera/libcameraservice/device3/Camera3IOStreamBase.h
@@ -56,11 +56,18 @@
int getMaxTotalBuffers() const { return mTotalBufferCount; }
protected:
size_t mTotalBufferCount;
+ // The maximum number of cached buffers allowed for this stream
+ size_t mMaxCachedBufferCount;
+
// sum of input and output buffers that are currently acquired by HAL
size_t mHandoutTotalBufferCount;
// number of output buffers that are currently acquired by HAL. This will be
// Redundant when camera3 streams are no longer bidirectional streams.
size_t mHandoutOutputBufferCount;
+ // number of cached output buffers that are currently queued in the camera
+ // server but not yet queued to the buffer queue.
+ size_t mCachedOutputBufferCount;
+
uint32_t mFrameCount;
// Last received output buffer's timestamp
nsecs_t mLastTimestamp;
@@ -97,6 +104,9 @@
virtual size_t getHandoutInputBufferCountLocked();
+ virtual size_t getCachedOutputBufferCountLocked() const;
+ virtual size_t getMaxCachedOutputBuffersLocked() const;
+
virtual status_t getEndpointUsage(uint64_t *usage) const = 0;
status_t getBufferPreconditionCheckLocked() const;
diff --git a/services/camera/libcameraservice/device3/Camera3OutputStream.cpp b/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
index 50314cc..8b3cf44 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
+++ b/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
@@ -419,6 +419,7 @@
mLock.unlock();
ANativeWindowBuffer *anwBuffer = container_of(buffer.buffer, ANativeWindowBuffer, handle);
+ bool bufferDeferred = false;
/**
* Return buffer back to ANativeWindow
*/
@@ -478,6 +479,7 @@
__FUNCTION__, mId, strerror(-res), res);
return res;
}
+ bufferDeferred = true;
} else {
nsecs_t presentTime = mSyncToDisplay ?
syncTimestampToDisplayLocked(captureTime) : captureTime;
@@ -501,6 +503,10 @@
}
mLock.lock();
+ if (bufferDeferred) {
+ mCachedOutputBufferCount++;
+ }
+
// Once a valid buffer has been returned to the queue, can no longer
// dequeue all buffers for preallocation.
if (buffer.status != CAMERA_BUFFER_STATUS_ERROR) {
@@ -696,10 +702,15 @@
!isVideoStream());
if (forceChoreographer || defaultToChoreographer) {
mSyncToDisplay = true;
+ // For choreographer synced stream, extra buffers aren't kept by
+ // camera service. So no need to update mMaxCachedBufferCount.
mTotalBufferCount += kDisplaySyncExtraBuffer;
} else if (defaultToSpacer) {
mPreviewFrameSpacer = new PreviewFrameSpacer(this, mConsumer);
- mTotalBufferCount ++;
+ // For preview frame spacer, the extra buffer is kept by camera
+ // service. So update mMaxCachedBufferCount.
+ mMaxCachedBufferCount = 1;
+ mTotalBufferCount += mMaxCachedBufferCount;
res = mPreviewFrameSpacer->run(String8::format("PreviewSpacer-%d", mId).string());
if (res != OK) {
ALOGE("%s: Unable to start preview spacer", __FUNCTION__);
@@ -968,6 +979,14 @@
return true;
}
+void Camera3OutputStream::onCachedBufferQueued() {
+ Mutex::Autolock l(mLock);
+ mCachedOutputBufferCount--;
+ // Signal whoever is waiting for the buffer to be returned to the buffer
+ // queue.
+ mOutputBufferReturnedSignal.signal();
+}
+
status_t Camera3OutputStream::disconnectLocked() {
status_t res;
diff --git a/services/camera/libcameraservice/device3/Camera3OutputStream.h b/services/camera/libcameraservice/device3/Camera3OutputStream.h
index 1b4739c..741bca2 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputStream.h
+++ b/services/camera/libcameraservice/device3/Camera3OutputStream.h
@@ -259,6 +259,7 @@
void setImageDumpMask(int mask) { mImageDumpMask = mask; }
bool shouldLogError(status_t res);
+ void onCachedBufferQueued();
protected:
Camera3OutputStream(int id, camera_stream_type_t type,
diff --git a/services/camera/libcameraservice/device3/Camera3Stream.cpp b/services/camera/libcameraservice/device3/Camera3Stream.cpp
index 7ad6649..88be9ff 100644
--- a/services/camera/libcameraservice/device3/Camera3Stream.cpp
+++ b/services/camera/libcameraservice/device3/Camera3Stream.cpp
@@ -665,11 +665,19 @@
}
}
- // Wait for new buffer returned back if we are running into the limit.
+ // Wait for new buffer returned back if we are running into the limit. There
+ // are 2 limits:
+ // 1. The number of HAL buffers is greater than max_buffers
+ // 2. The number of HAL buffers + cached buffers is greater than max_buffers
+ // + maxCachedBuffers
size_t numOutstandingBuffers = getHandoutOutputBufferCountLocked();
- if (numOutstandingBuffers == camera_stream::max_buffers) {
- ALOGV("%s: Already dequeued max output buffers (%d), wait for next returned one.",
- __FUNCTION__, camera_stream::max_buffers);
+ size_t numCachedBuffers = getCachedOutputBufferCountLocked();
+ size_t maxNumCachedBuffers = getMaxCachedOutputBuffersLocked();
+ while (numOutstandingBuffers == camera_stream::max_buffers ||
+ numOutstandingBuffers + numCachedBuffers ==
+ camera_stream::max_buffers + maxNumCachedBuffers) {
+ ALOGV("%s: Already dequeued max output buffers (%d(+%zu)), wait for next returned one.",
+ __FUNCTION__, camera_stream::max_buffers, maxNumCachedBuffers);
nsecs_t waitStart = systemTime(SYSTEM_TIME_MONOTONIC);
if (waitBufferTimeout < kWaitForBufferDuration) {
waitBufferTimeout = kWaitForBufferDuration;
@@ -687,12 +695,16 @@
}
size_t updatedNumOutstandingBuffers = getHandoutOutputBufferCountLocked();
- if (updatedNumOutstandingBuffers >= numOutstandingBuffers) {
- ALOGE("%s: outsanding buffer count goes from %zu to %zu, "
+ size_t updatedNumCachedBuffers = getCachedOutputBufferCountLocked();
+ if (updatedNumOutstandingBuffers >= numOutstandingBuffers &&
+ updatedNumCachedBuffers == numCachedBuffers) {
+ ALOGE("%s: outstanding buffer count goes from %zu to %zu, "
"getBuffer(s) call must not run in parallel!", __FUNCTION__,
numOutstandingBuffers, updatedNumOutstandingBuffers);
return INVALID_OPERATION;
}
+ numOutstandingBuffers = updatedNumOutstandingBuffers;
+ numCachedBuffers = updatedNumCachedBuffers;
}
res = getBufferLocked(buffer, surface_ids);
@@ -1057,11 +1069,20 @@
}
size_t numOutstandingBuffers = getHandoutOutputBufferCountLocked();
- // Wait for new buffer returned back if we are running into the limit.
- while (numOutstandingBuffers + numBuffersRequested > camera_stream::max_buffers) {
- ALOGV("%s: Already dequeued %zu output buffers and requesting %zu (max is %d), waiting.",
- __FUNCTION__, numOutstandingBuffers, numBuffersRequested,
- camera_stream::max_buffers);
+ size_t numCachedBuffers = getCachedOutputBufferCountLocked();
+ size_t maxNumCachedBuffers = getMaxCachedOutputBuffersLocked();
+ // Wait for new buffer returned back if we are running into the limit. There
+ // are 2 limits:
+ // 1. The number of HAL buffers is greater than max_buffers
+ // 2. The number of HAL buffers + cached buffers is greater than max_buffers
+ // + maxCachedBuffers
+ while (numOutstandingBuffers + numBuffersRequested > camera_stream::max_buffers ||
+ numOutstandingBuffers + numCachedBuffers + numBuffersRequested >
+ camera_stream::max_buffers + maxNumCachedBuffers) {
+ ALOGV("%s: Already dequeued %zu(+%zu) output buffers and requesting %zu "
+ "(max is %d(+%zu)), waiting.", __FUNCTION__, numOutstandingBuffers,
+ numCachedBuffers, numBuffersRequested, camera_stream::max_buffers,
+ maxNumCachedBuffers);
nsecs_t waitStart = systemTime(SYSTEM_TIME_MONOTONIC);
if (waitBufferTimeout < kWaitForBufferDuration) {
waitBufferTimeout = kWaitForBufferDuration;
@@ -1078,13 +1099,16 @@
return res;
}
size_t updatedNumOutstandingBuffers = getHandoutOutputBufferCountLocked();
- if (updatedNumOutstandingBuffers >= numOutstandingBuffers) {
- ALOGE("%s: outsanding buffer count goes from %zu to %zu, "
+ size_t updatedNumCachedBuffers = getCachedOutputBufferCountLocked();
+ if (updatedNumOutstandingBuffers >= numOutstandingBuffers &&
+ updatedNumCachedBuffers == numCachedBuffers) {
+ ALOGE("%s: outstanding buffer count goes from %zu to %zu, "
"getBuffer(s) call must not run in parallel!", __FUNCTION__,
numOutstandingBuffers, updatedNumOutstandingBuffers);
return INVALID_OPERATION;
}
numOutstandingBuffers = updatedNumOutstandingBuffers;
+ numCachedBuffers = updatedNumCachedBuffers;
}
res = getBuffersLocked(buffers);
diff --git a/services/camera/libcameraservice/device3/Camera3Stream.h b/services/camera/libcameraservice/device3/Camera3Stream.h
index d429e6c..214618a 100644
--- a/services/camera/libcameraservice/device3/Camera3Stream.h
+++ b/services/camera/libcameraservice/device3/Camera3Stream.h
@@ -558,6 +558,10 @@
// Get handout input buffer count.
virtual size_t getHandoutInputBufferCountLocked() = 0;
+ // Get cached output buffer count.
+ virtual size_t getCachedOutputBufferCountLocked() const = 0;
+ virtual size_t getMaxCachedOutputBuffersLocked() const = 0;
+
// Get the usage flags for the other endpoint, or return
// INVALID_OPERATION if they cannot be obtained.
virtual status_t getEndpointUsage(uint64_t *usage) const = 0;
@@ -576,6 +580,8 @@
uint64_t mUsage;
+ Condition mOutputBufferReturnedSignal;
+
private:
// Previously configured stream properties (post HAL override)
uint64_t mOldUsage;
@@ -583,7 +589,6 @@
int mOldFormat;
android_dataspace mOldDataSpace;
- Condition mOutputBufferReturnedSignal;
Condition mInputBufferReturnedSignal;
static const nsecs_t kWaitForBufferDuration = 3000000000LL; // 3000 ms
diff --git a/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp b/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp
index 0439501..67f42b4 100644
--- a/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp
+++ b/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp
@@ -122,6 +122,7 @@
}
}
+ parent->onCachedBufferQueued();
mLastCameraPresentTime = currentTime;
mLastCameraReadoutTime = bufferHolder.readoutTimestamp;
}