BufferQueue/SF: Add OccupancyTracker
Adds an OccupancyTracker to BufferQueue. This module keeps track of
how many buffers are in the queue over time, which, in combination
with various aggregation of these statistics, allows SurfaceFlinger
to report what fraction of the time a given layer was double- or
triple-buffered.
Change-Id: Ida6e967dc5483c00a633e9fe03998e420dd88502
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 633e956..8263994 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -42,6 +42,7 @@
#include <gui/ISurfaceComposer.h>
#include <gui/ISurfaceComposerClient.h>
+#include <gui/OccupancyTracker.h>
#include <hardware/hwcomposer_defs.h>
@@ -57,6 +58,9 @@
#include "DisplayHardware/HWComposer.h"
#include "Effects/Daltonizer.h"
+#include <map>
+#include <string>
+
namespace android {
// ---------------------------------------------------------------------------
@@ -432,6 +436,10 @@
void dumpStaticScreenStats(String8& result) const;
+ void recordBufferingStats(const char* layerName,
+ std::vector<OccupancyTracker::Segment>&& history);
+ void dumpBufferingStats(String8& result) const;
+
/* ------------------------------------------------------------------------
* Attributes
*/
@@ -526,6 +534,29 @@
nsecs_t mFrameBuckets[NUM_BUCKETS];
nsecs_t mTotalTime;
std::atomic<nsecs_t> mLastSwapTime;
+
+ // Double- vs. triple-buffering stats
+ struct BufferingStats {
+ BufferingStats()
+ : numSegments(0),
+ totalTime(0),
+ twoBufferTime(0),
+ doubleBufferedTime(0),
+ tripleBufferedTime(0) {}
+
+ size_t numSegments;
+ nsecs_t totalTime;
+
+ // "Two buffer" means that a third buffer was never used, whereas
+ // "double-buffered" means that on average the segment only used two
+ // buffers (though it may have used a third for some part of the
+ // segment)
+ nsecs_t twoBufferTime;
+ nsecs_t doubleBufferedTime;
+ nsecs_t tripleBufferedTime;
+ };
+ mutable Mutex mBufferingStatsMutex;
+ std::unordered_map<std::string, BufferingStats> mBufferingStats;
};
}; // namespace android