commit f8734e014d3a5596be2edc6ee85dbda7589bb889
author Dominik Laskowski <domlaskowski@google.com> Fri Aug 26 09:06:59 2022 -0700
committer Dominik Laskowski <domlaskowski@google.com> Thu Sep 08 08:48:21 2022 -0700
tree fd30cadac81cfd364477ef0c9247fc8ea7b32dbf
parent f2595446af5d9bf2ca4b2e5bf07dfbbd842e61ec

SF: Enforce thread safety of active mode access

Provide two RefreshRateConfigs APIs for retrieving the active mode:
getActiveMode for access from the main thread (which does not need
to lock nor copy), and getActiveModePtr for other threads.

Bug: 241285191
Test: Build (-Wthread-safety)
Change-Id: If156d85861ec2d82a394ba181314a6ba3048974f

services/surfaceflinger/SurfaceFlinger.h

diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 2af17e7..f7684a0 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -648,22 +648,20 @@
     // Show spinner with refresh rate overlay
     bool mRefreshRateOverlaySpinner = false;
 
-    // Called on the main thread in response to initializeDisplays()
-    void onInitializeDisplays() REQUIRES(mStateLock);
     // Sets the desired active mode bit. It obtains the lock, and sets mDesiredActiveMode.
     void setDesiredActiveMode(const ActiveModeInfo& info) REQUIRES(mStateLock);
     status_t setActiveModeFromBackdoor(const sp<display::DisplayToken>&, DisplayModeId);
     // Sets the active mode and a new refresh rate in SF.
-    void updateInternalStateWithChangedMode() REQUIRES(mStateLock);
+    void updateInternalStateWithChangedMode() REQUIRES(mStateLock, kMainThreadContext);
     // Calls to setActiveMode on the main thread if there is a pending mode change
     // that needs to be applied.
-    void setActiveModeInHwcIfNeeded() REQUIRES(mStateLock);
+    void setActiveModeInHwcIfNeeded() REQUIRES(mStateLock, kMainThreadContext);
     void clearDesiredActiveModeState(const sp<DisplayDevice>&) REQUIRES(mStateLock);
     // Called when active mode is no longer is progress
     void desiredActiveModeChangeDone(const sp<DisplayDevice>&) REQUIRES(mStateLock);
     // Called on the main thread in response to setPowerMode()
     void setPowerModeInternal(const sp<DisplayDevice>& display, hal::PowerMode mode)
-            REQUIRES(mStateLock);
+            REQUIRES(mStateLock, kMainThreadContext);
 
     // Returns true if the display has a visible HDR layer in its layer stack.
     bool hasVisibleHdrLayer(const sp<DisplayDevice>& display) REQUIRES(mStateLock);
@@ -680,8 +678,9 @@
             const std::optional<scheduler::RefreshRateConfigs::Policy>& policy, bool overridePolicy)
             EXCLUDES(mStateLock);
 
-    void commitTransactions() EXCLUDES(mStateLock);
-    void commitTransactionsLocked(uint32_t transactionFlags) REQUIRES(mStateLock);
+    void commitTransactions() EXCLUDES(mStateLock) REQUIRES(kMainThreadContext);
+    void commitTransactionsLocked(uint32_t transactionFlags)
+            REQUIRES(mStateLock, kMainThreadContext);
     void doCommitTransactions() REQUIRES(mStateLock);
 
     // Returns whether a new buffer has been latched.
@@ -824,8 +823,10 @@
     /*
      * Display and layer stack management
      */
-    // called when starting, or restarting after system_server death
+
+    // Called during boot, and restart after system_server death.
     void initializeDisplays();
+    void onInitializeDisplays() REQUIRES(mStateLock, kMainThreadContext);
 
     bool isDisplayActiveLocked(const sp<const DisplayDevice>& display) const REQUIRES(mStateLock) {
         return display->getDisplayToken() == mActiveDisplayToken;
@@ -957,11 +958,12 @@
             const DisplayDeviceState& state,
             const sp<compositionengine::DisplaySurface>& displaySurface,
             const sp<IGraphicBufferProducer>& producer) REQUIRES(mStateLock);
-    void processDisplayChangesLocked() REQUIRES(mStateLock);
+    void processDisplayChangesLocked() REQUIRES(mStateLock, kMainThreadContext);
     void processDisplayRemoved(const wp<IBinder>& displayToken) REQUIRES(mStateLock);
     void processDisplayChanged(const wp<IBinder>& displayToken,
                                const DisplayDeviceState& currentState,
-                               const DisplayDeviceState& drawingState) REQUIRES(mStateLock);
+                               const DisplayDeviceState& drawingState)
+            REQUIRES(mStateLock, kMainThreadContext);
 
     void dispatchDisplayHotplugEvent(PhysicalDisplayId displayId, bool connected);
 
@@ -1022,7 +1024,8 @@
     VirtualDisplayId acquireVirtualDisplay(ui::Size, ui::PixelFormat) REQUIRES(mStateLock);
     void releaseVirtualDisplay(VirtualDisplayId);
 
-    void onActiveDisplayChangedLocked(const sp<DisplayDevice>& activeDisplay) REQUIRES(mStateLock);
+    void onActiveDisplayChangedLocked(const sp<DisplayDevice>& activeDisplay)
+            REQUIRES(mStateLock, kMainThreadContext);
 
     void onActiveDisplaySizeChanged(const sp<DisplayDevice>& activeDisplay);
 
@@ -1096,7 +1099,7 @@
     int getMaxAcquiredBufferCountForRefreshRate(Fps refreshRate) const;
 
     void updateInternalDisplayVsyncLocked(const sp<DisplayDevice>& activeDisplay)
-            REQUIRES(mStateLock);
+            REQUIRES(mStateLock, kMainThreadContext);
 
     bool isHdrLayer(Layer* layer) const;