Send HWUI load reset hint when Choreographer registers a callback

Send a load reset hint hint to DrawFrameTask through ThreadedRenderer
from ViewRootImpl whenever Choreographer registers a callback. This
allows the PowerHAL to allocate more resources for HWUI in response to
upcoming work, helping prevent frame drop.

Bug: b/243938267
Test: manual

Change-Id: Ie2cf809cf85530af04f4d0db3407853d4da03d62
diff --git a/libs/hwui/renderthread/DrawFrameTask.cpp b/libs/hwui/renderthread/DrawFrameTask.cpp
index dc7676c..cb30614 100644
--- a/libs/hwui/renderthread/DrawFrameTask.cpp
+++ b/libs/hwui/renderthread/DrawFrameTask.cpp
@@ -42,6 +42,7 @@
                                                       size_t, int64_t);
 typedef void (*APH_updateTargetWorkDuration)(APerformanceHintSession*, int64_t);
 typedef void (*APH_reportActualWorkDuration)(APerformanceHintSession*, int64_t);
+typedef void (*APH_sendHint)(APerformanceHintSession* session, int32_t);
 typedef void (*APH_closeSession)(APerformanceHintSession* session);
 
 bool gAPerformanceHintBindingInitialized = false;
@@ -49,6 +50,7 @@
 APH_createSession gAPH_createSessionFn = nullptr;
 APH_updateTargetWorkDuration gAPH_updateTargetWorkDurationFn = nullptr;
 APH_reportActualWorkDuration gAPH_reportActualWorkDurationFn = nullptr;
+APH_sendHint gAPH_sendHintFn = nullptr;
 APH_closeSession gAPH_closeSessionFn = nullptr;
 
 void ensureAPerformanceHintBindingInitialized() {
@@ -77,6 +79,10 @@
             gAPH_reportActualWorkDurationFn == nullptr,
             "Failed to find required symbol APerformanceHint_reportActualWorkDuration!");
 
+    gAPH_sendHintFn = (APH_sendHint)dlsym(handle_, "APerformanceHint_sendHint");
+    LOG_ALWAYS_FATAL_IF(gAPH_sendHintFn == nullptr,
+                        "Failed to find required symbol APerformanceHint_sendHint!");
+
     gAPH_closeSessionFn = (APH_closeSession)dlsym(handle_, "APerformanceHint_closeSession");
     LOG_ALWAYS_FATAL_IF(gAPH_closeSessionFn == nullptr,
                         "Failed to find required symbol APerformanceHint_closeSession!");
@@ -239,6 +245,16 @@
     mLastDequeueBufferDuration = dequeueBufferDuration;
 }
 
+void DrawFrameTask::sendLoadResetHint() {
+    if (!(Properties::useHintManager && Properties::isDrawingEnabled())) return;
+    if (!mHintSessionWrapper) mHintSessionWrapper.emplace(mUiThreadId, mRenderThreadId);
+    nsecs_t now = systemTime();
+    if (now - mLastFrameNotification > kResetHintTimeout) {
+        mHintSessionWrapper->sendHint(SessionHint::CPU_LOAD_RESET);
+    }
+    mLastFrameNotification = now;
+}
+
 bool DrawFrameTask::syncFrameState(TreeInfo& info) {
     ATRACE_CALL();
     int64_t vsync = mFrameInfo[static_cast<int>(FrameInfoIndex::Vsync)];
@@ -327,6 +343,12 @@
     }
 }
 
+void DrawFrameTask::HintSessionWrapper::sendHint(SessionHint hint) {
+    if (mHintSession && Properties::isDrawingEnabled()) {
+        gAPH_sendHintFn(mHintSession, static_cast<int>(hint));
+    }
+}
+
 } /* namespace renderthread */
 } /* namespace uirenderer */
 } /* namespace android */
diff --git a/libs/hwui/renderthread/DrawFrameTask.h b/libs/hwui/renderthread/DrawFrameTask.h
index d6fc292..7eae41c 100644
--- a/libs/hwui/renderthread/DrawFrameTask.h
+++ b/libs/hwui/renderthread/DrawFrameTask.h
@@ -28,6 +28,7 @@
 #include "../Rect.h"
 #include "../TreeInfo.h"
 #include "RenderTask.h"
+#include "utils/TimeUtils.h"
 
 namespace android {
 namespace uirenderer {
@@ -90,6 +91,8 @@
 
     void forceDrawNextFrame() { mForceDrawFrame = true; }
 
+    void sendLoadResetHint();
+
 private:
     class HintSessionWrapper {
     public:
@@ -98,6 +101,7 @@
 
         void updateTargetWorkDuration(long targetDurationNanos);
         void reportActualWorkDuration(long actualDurationNanos);
+        void sendHint(SessionHint hint);
 
     private:
         APerformanceHintSession* mHintSession = nullptr;
@@ -135,6 +139,9 @@
     nsecs_t mLastTargetWorkDuration = 0;
     std::optional<HintSessionWrapper> mHintSessionWrapper;
 
+    nsecs_t mLastFrameNotification = 0;
+    nsecs_t kResetHintTimeout = 100_ms;
+
     bool mForceDrawFrame = false;
 };
 
diff --git a/libs/hwui/renderthread/RenderProxy.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index 3324715..03a2bc9 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -236,6 +236,10 @@
     mRenderThread.queue().post([this]() { mContext->notifyFramePending(); });
 }
 
+void RenderProxy::notifyCallbackPending() {
+    mDrawFrameTask.sendLoadResetHint();
+}
+
 void RenderProxy::dumpProfileInfo(int fd, int dumpFlags) {
     mRenderThread.queue().runSync([&]() {
         std::lock_guard lock(mRenderThread.getJankDataMutex());
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index 2a99a73..a21faa8 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -109,6 +109,7 @@
     static int maxTextureSize();
     void stopDrawing();
     void notifyFramePending();
+    void notifyCallbackPending();
 
     void dumpProfileInfo(int fd, int dumpFlags);
     // Not exported, only used for testing