Add new mode for SCHED_FIFO on UI and RenderThreads.

Add a new mode, controlled by sys.use_fifo_ui property, that enables the
top app's UI and RenderThread to be SCHED_FIFO. This eliminates almost
all jank due to scheduling competition with non-UI critical
threads. This mode may not be suitable for all devices.

bug 24503801

Change-Id: I7b8a31830ad80f7efa00236928d5476998ed4e00

2 files changed, 5 insertions, 0 deletions

diff --git a/libs/hwui/renderthread/RenderProxy.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index 54af2829cf40..06a24b248bf6 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -514,6 +514,10 @@ void RenderProxy::setProcessStatsBuffer(int fd) {
     post(task);
 }
 
+int RenderProxy::getRenderThreadTid() {
+    return mRenderThread.getTid();
+}
+
 CREATE_BRIDGE3(addRenderNode, CanvasContext* context, RenderNode* node, bool placeFront) {
     args->context->addRenderNode(args->node, args->placeFront);
     return nullptr;
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index 898b31421aad..e31062c83734 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -115,6 +115,7 @@ public:
 
     ANDROID_API void setTextureAtlas(const sp<GraphicBuffer>& buffer, int64_t* map, size_t size);
     ANDROID_API void setProcessStatsBuffer(int fd);
+    ANDROID_API int getRenderThreadTid();
 
     ANDROID_API void serializeDisplayListTree();