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/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);