Move SF trace logging into a separate thread
SF trace logging currently happens on the main thread, which affects
performance. Move it to a separate thread to mitigate the overhead.
Use a lock to prevent the drawing state to be updated while it is being
dumped.
Also, allow the buffer size for SF traces to be configured. Current buffer
size is fixed to 100MB, which is unfeasible for phones with lower resources.
Created option 1029 to manually update the buffer size.
To trigger the option use:
- adb shell su root service call SurfaceFlinger 1029 i32 <SIZE>
This option trigger an "Invalid Argument" error if it receives a
negative value.
Finally, just log Winscope trace if visible regions are dirty. SF
currently logs all Winscope frames. It should log only if there is a
change to mitigate resource consumption.
Test: Flash a device. Start a trace. Run systrace. Record a trace. Check
if the `commitTransaction` trace happens in a separate SF thread and
doesn't block the critical path
Change-Id: Ie05ad5c025a185b28209bbc5d26655ba9ff9042b
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 96292a8..ea1901b 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -274,6 +274,7 @@
mDebugInTransaction(0),
mLastTransactionTime(0),
mForceFullDamage(false),
+ mTracing(*this),
mTimeStats(factory.createTimeStats()),
mRefreshStartTime(0),
mHasPoweredOff(false),
@@ -1671,7 +1672,6 @@
doComposition(display, repaintEverything);
}
- doTracing("handleRefresh");
logLayerStats();
postFrame();
@@ -1700,6 +1700,9 @@
if (mVisibleRegionsDirty) {
computeLayerBounds();
+ if (mTracingEnabled) {
+ mTracing.notify("visibleRegionsDirty");
+ }
}
for (auto& layer : mLayersPendingRefresh) {
@@ -1838,14 +1841,6 @@
prepareFrame(displayDevice);
}
-void SurfaceFlinger::doTracing(const char* where) {
- ATRACE_CALL();
- ATRACE_NAME(where);
- if (CC_UNLIKELY(mTracing.isEnabled())) {
- mTracing.traceLayers(where, dumpProtoInfo(LayerVector::StateSet::Drawing));
- }
-}
-
void SurfaceFlinger::logLayerStats() {
ATRACE_CALL();
if (CC_UNLIKELY(mLayerStats.isEnabled())) {
@@ -2920,18 +2915,39 @@
// we composite should be considered an animation as well.
mAnimCompositionPending = mAnimTransactionPending;
- mDrawingState = mCurrentState;
- // clear the "changed" flags in current state
- mCurrentState.colorMatrixChanged = false;
+ withTracingLock([&]() {
+ mDrawingState = mCurrentState;
+ // clear the "changed" flags in current state
+ mCurrentState.colorMatrixChanged = false;
- mDrawingState.traverseInZOrder([](Layer* layer) {
- layer->commitChildList();
+ mDrawingState.traverseInZOrder([](Layer* layer) { layer->commitChildList(); });
});
+
mTransactionPending = false;
mAnimTransactionPending = false;
mTransactionCV.broadcast();
}
+void SurfaceFlinger::withTracingLock(std::function<void()> lockedOperation) {
+ if (mTracingEnabledChanged) {
+ mTracingEnabled = mTracing.isEnabled();
+ mTracingEnabledChanged = false;
+ }
+
+ // Synchronize with Tracing thread
+ std::unique_lock<std::mutex> lock;
+ if (mTracingEnabled) {
+ lock = std::unique_lock<std::mutex>(mDrawingStateLock);
+ }
+
+ lockedOperation();
+
+ // Synchronize with Tracing thread
+ if (mTracingEnabled) {
+ lock.unlock();
+ }
+}
+
void SurfaceFlinger::computeVisibleRegions(const sp<const DisplayDevice>& displayDevice,
Region& outDirtyRegion, Region& outOpaqueRegion) {
ATRACE_CALL();
@@ -5080,13 +5096,24 @@
n = data.readInt32();
if (n) {
ALOGD("LayerTracing enabled");
+ Mutex::Autolock lock(mStateLock);
+ mTracingEnabledChanged = true;
mTracing.enable();
- doTracing("tracing.enable");
reply->writeInt32(NO_ERROR);
} else {
ALOGD("LayerTracing disabled");
- status_t err = mTracing.disable();
- reply->writeInt32(err);
+ bool writeFile = false;
+ {
+ Mutex::Autolock lock(mStateLock);
+ mTracingEnabledChanged = true;
+ writeFile = mTracing.disable();
+ }
+
+ if (writeFile) {
+ reply->writeInt32(mTracing.writeToFile());
+ } else {
+ reply->writeInt32(NO_ERROR);
+ }
}
return NO_ERROR;
}
@@ -5125,6 +5152,20 @@
reply->writeBool(getHwComposer().isUsingVrComposer());
return NO_ERROR;
}
+ // Set buffer size for SF tracing (value in KB)
+ case 1029: {
+ n = data.readInt32();
+ if (n <= 0 || n > MAX_TRACING_MEMORY) {
+ ALOGW("Invalid buffer size: %d KB", n);
+ reply->writeInt32(BAD_VALUE);
+ return BAD_VALUE;
+ }
+
+ ALOGD("Updating trace buffer to %d KB", n);
+ mTracing.setBufferSize(n * 1024);
+ reply->writeInt32(NO_ERROR);
+ return NO_ERROR;
+ }
// Is device color managed?
case 1030: {
reply->writeBool(useColorManagement);