SF: add HWVsync state to dumpsys

Log debugging information about whether HWVsync callbacks
where enabled with HWC.

Bug: 201605862
Test: adb logcat -s SurfaceFlinger
Change-Id: Iaa13a92d37fcfea1328a6e91b17372c3737ffff6
diff --git a/services/surfaceflinger/DisplayHardware/Hal.h b/services/surfaceflinger/DisplayHardware/Hal.h
index bb2888e..02d0658 100644
--- a/services/surfaceflinger/DisplayHardware/Hal.h
+++ b/services/surfaceflinger/DisplayHardware/Hal.h
@@ -166,4 +166,15 @@
     }
 }
 
+inline std::string to_string(hardware::graphics::composer::hal::Vsync vsync) {
+    switch (vsync) {
+        case hardware::graphics::composer::hal::Vsync::ENABLE:
+            return "Enable";
+        case hardware::graphics::composer::hal::Vsync::DISABLE:
+            return "Disable";
+        default:
+            return "Unknown";
+    }
+}
+
 } // namespace android
diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index 1a5f0f4..1989d57 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -324,6 +324,7 @@
         thread = mConnections[handle].thread.get();
     }
     thread->onScreenAcquired();
+    mScreenAcquired = true;
 }
 
 void Scheduler::onScreenReleased(ConnectionHandle handle) {
@@ -334,6 +335,7 @@
         thread = mConnections[handle].thread.get();
     }
     thread->onScreenReleased();
+    mScreenAcquired = false;
 }
 
 void Scheduler::onFrameRateOverridesChanged(ConnectionHandle handle, PhysicalDisplayId displayId) {
@@ -760,6 +762,13 @@
         }
         StringAppendF(&result, "}\n");
     }
+
+    {
+        std::lock_guard lock(mHWVsyncLock);
+        StringAppendF(&result,
+                      "mScreenAcquired=%d mPrimaryHWVsyncEnabled=%d mHWVsyncAvailable=%d\n",
+                      mScreenAcquired.load(), mPrimaryHWVsyncEnabled, mHWVsyncAvailable);
+    }
 }
 
 void Scheduler::dumpVsync(std::string& s) const {
diff --git a/services/surfaceflinger/Scheduler/Scheduler.h b/services/surfaceflinger/Scheduler/Scheduler.h
index 2f97328..ee519f3 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.h
+++ b/services/surfaceflinger/Scheduler/Scheduler.h
@@ -282,7 +282,7 @@
     InjectVSyncSource* mVSyncInjector = nullptr;
     ConnectionHandle mInjectorConnectionHandle;
 
-    std::mutex mHWVsyncLock;
+    mutable std::mutex mHWVsyncLock;
     bool mPrimaryHWVsyncEnabled GUARDED_BY(mHWVsyncLock) = false;
     bool mHWVsyncAvailable GUARDED_BY(mHWVsyncLock) = false;
 
@@ -345,6 +345,9 @@
             GUARDED_BY(mFrameRateOverridesLock);
     scheduler::RefreshRateConfigs::UidToFrameRateOverride mFrameRateOverridesFromBackdoor
             GUARDED_BY(mFrameRateOverridesLock);
+
+    // Keeps track of whether the screen is acquired for debug
+    std::atomic<bool> mScreenAcquired = false;
 };
 
 } // namespace android
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 82bd398..39d4d2a 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -1824,7 +1824,7 @@
 
         if (const auto display = getDefaultDisplayDeviceLocked();
             display && display->isPoweredOn()) {
-            getHwComposer().setVsyncEnabled(display->getPhysicalId(), mHWCVsyncPendingState);
+            setHWCVsyncEnabled(display->getPhysicalId(), mHWCVsyncPendingState);
         }
     }));
 }
@@ -4585,6 +4585,12 @@
         return;
     }
 
+    const auto activeDisplay = getDisplayDeviceLocked(mActiveDisplayToken);
+    if (activeDisplay != display && display->isInternal() && activeDisplay &&
+        activeDisplay->isPoweredOn()) {
+        ALOGW("Trying to change power mode on non active display while the active display is ON");
+    }
+
     display->setPowerMode(mode);
 
     if (mInterceptor->isEnabled()) {
@@ -4592,7 +4598,7 @@
     }
     const auto vsyncPeriod = display->refreshRateConfigs().getCurrentRefreshRate().getVsyncPeriod();
     if (currentMode == hal::PowerMode::OFF) {
-        const auto activeDisplay = getDisplayDeviceLocked(mActiveDisplayToken);
+        // Turn on the display
         if (display->isInternal() && (!activeDisplay || !activeDisplay->isPoweredOn())) {
             onActiveDisplayChangedLocked(display);
         }
@@ -4606,7 +4612,7 @@
         }
         getHwComposer().setPowerMode(displayId, mode);
         if (display->isInternal() && mode != hal::PowerMode::DOZE_SUSPEND) {
-            getHwComposer().setVsyncEnabled(displayId, mHWCVsyncPendingState);
+            setHWCVsyncEnabled(displayId, mHWCVsyncPendingState);
             mScheduler->onScreenAcquired(mAppConnectionHandle);
             mScheduler->resyncToHardwareVsync(true, vsyncPeriod);
         }
@@ -4628,7 +4634,7 @@
         }
 
         // Make sure HWVsync is disabled before turning off the display
-        getHwComposer().setVsyncEnabled(displayId, hal::Vsync::DISABLE);
+        setHWCVsyncEnabled(displayId, hal::Vsync::DISABLE);
 
         getHwComposer().setPowerMode(displayId, mode);
         mVisibleRegionsDirty = true;
@@ -4831,6 +4837,8 @@
 
     mScheduler->dump(mAppConnectionHandle, result);
     mScheduler->dumpVsync(result);
+    StringAppendF(&result, "mHWCVsyncPendingState=%s mLastHWCVsyncState=%s\n",
+                  to_string(mHWCVsyncPendingState).c_str(), to_string(mLastHWCVsyncState).c_str());
 }
 
 void SurfaceFlinger::dumpPlannerInfo(const DumpArgs& args, std::string& result) const {
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index dba2bd6..9e2e216 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -1064,6 +1064,11 @@
      */
     nsecs_t getVsyncPeriodFromHWC() const REQUIRES(mStateLock);
 
+    void setHWCVsyncEnabled(PhysicalDisplayId id, hal::Vsync enabled) {
+        mLastHWCVsyncState = enabled;
+        getHwComposer().setVsyncEnabled(id, enabled);
+    }
+
     // Sets the refresh rate by switching active configs, if they are available for
     // the desired refresh rate.
     void changeRefreshRateLocked(const RefreshRate&, Scheduler::ModeEvent) REQUIRES(mStateLock);
@@ -1422,6 +1427,7 @@
     std::atomic<nsecs_t> mExpectedPresentTime = 0;
     nsecs_t mScheduledPresentTime = 0;
     hal::Vsync mHWCVsyncPendingState = hal::Vsync::DISABLE;
+    hal::Vsync mLastHWCVsyncState = hal::Vsync::DISABLE;
 
     // below flags are set by main thread only
     bool mSetActiveModePending = false;