diff --git a/services/surfaceflinger/DispSync.cpp b/services/surfaceflinger/DispSync.cpp
index 7acbd11..37dc27d 100644
--- a/services/surfaceflinger/DispSync.cpp
+++ b/services/surfaceflinger/DispSync.cpp
@@ -222,7 +222,13 @@
                 // Pretend that the last time this event was handled at the same frame but with the
                 // new offset to allow for a seamless offset change without double-firing or
                 // skipping.
-                listener.mLastEventTime -= (oldPhase - phase);
+                nsecs_t diff = oldPhase - phase;
+                if (diff > mPeriod / 2) {
+                    diff -= mPeriod;
+                } else if (diff < -mPeriod / 2) {
+                    diff += mPeriod;
+                }
+                listener.mLastEventTime -= diff;
                 mCond.signal();
                 return NO_ERROR;
             }
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 2a2be83..e39e623 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -332,11 +332,26 @@
     auto listSize = property_get_int32("debug.sf.max_igbp_list_size", int32_t(defaultListSize));
     mMaxGraphicBufferProducerListSize = (listSize > 0) ? size_t(listSize) : defaultListSize;
 
-    property_get("debug.sf.early_phase_offset_ns", value, "0");
-    const int earlyWakeupOffsetOffsetNs = atoi(value);
-    ALOGI_IF(earlyWakeupOffsetOffsetNs != 0, "Enabling separate early offset");
-    mVsyncModulator.setPhaseOffsets(sfVsyncPhaseOffsetNs - earlyWakeupOffsetOffsetNs,
-            sfVsyncPhaseOffsetNs);
+    property_get("debug.sf.early_phase_offset_ns", value, "-1");
+    const int earlySfOffsetNs = atoi(value);
+
+    property_get("debug.sf.early_gl_phase_offset_ns", value, "-1");
+    const int earlyGlSfOffsetNs = atoi(value);
+
+    property_get("debug.sf.early_app_phase_offset_ns", value, "-1");
+    const int earlyAppOffsetNs = atoi(value);
+
+    property_get("debug.sf.early_gl_app_phase_offset_ns", value, "-1");
+    const int earlyGlAppOffsetNs = atoi(value);
+
+    const VSyncModulator::Offsets earlyOffsets =
+            {earlySfOffsetNs != -1 ? earlySfOffsetNs : sfVsyncPhaseOffsetNs,
+            earlyAppOffsetNs != -1 ? earlyAppOffsetNs : vsyncPhaseOffsetNs};
+    const VSyncModulator::Offsets earlyGlOffsets =
+            {earlyGlSfOffsetNs != -1 ? earlyGlSfOffsetNs : sfVsyncPhaseOffsetNs,
+            earlyGlAppOffsetNs != -1 ? earlyGlAppOffsetNs : vsyncPhaseOffsetNs};
+    mVsyncModulator.setPhaseOffsets(earlyOffsets, earlyGlOffsets,
+            {sfVsyncPhaseOffsetNs, vsyncPhaseOffsetNs});
 
     // We should be reading 'persist.sys.sf.color_saturation' here
     // but since /data may be encrypted, we need to wait until after vold
@@ -651,7 +666,7 @@
                                                 },
                                                 "sfEventThread");
     mEventQueue->setEventThread(mSFEventThread.get());
-    mVsyncModulator.setEventThread(mSFEventThread.get());
+    mVsyncModulator.setEventThreads(mSFEventThread.get(), mEventThread.get());
 
     // Get a RenderEngine for the given display / config (can't fail)
     getBE().mRenderEngine =
@@ -4168,15 +4183,27 @@
     result.append("DispSync configuration:\n");
     colorizer.reset(result);
 
+    const auto [sfEarlyOffset, appEarlyOffset] = mVsyncModulator.getEarlyOffsets();
+    const auto [sfEarlyGlOffset, appEarlyGlOffset] = mVsyncModulator.getEarlyGlOffsets();
     if (const auto displayId = DisplayDevice::DISPLAY_PRIMARY;
         getHwComposer().isConnected(displayId)) {
         const auto activeConfig = getHwComposer().getActiveConfig(displayId);
-        result.appendFormat("Display %d: app phase %" PRId64 " ns, sf phase %" PRId64
-                            " ns, early sf phase %" PRId64 " ns, present offset %" PRId64
-                            " ns (refresh %" PRId64 " ns)",
-                            displayId, vsyncPhaseOffsetNs, sfVsyncPhaseOffsetNs,
-                            mVsyncModulator.getEarlyPhaseOffset(), dispSyncPresentTimeOffset,
-                            activeConfig->getVsyncPeriod());
+        result.appendFormat("Display %d: "
+                "app phase %" PRId64 " ns, "
+                "sf phase %" PRId64 " ns, "
+                "early app phase %" PRId64 " ns, "
+                "early sf phase %" PRId64 " ns, "
+                "early app gl phase %" PRId64 " ns, "
+                "early sf gl phase %" PRId64 " ns, "
+                "present offset %" PRId64 " ns (refresh %" PRId64 " ns)",
+                displayId,
+                vsyncPhaseOffsetNs,
+                sfVsyncPhaseOffsetNs,
+                appEarlyOffset,
+                sfEarlyOffset,
+                appEarlyGlOffset,
+                sfEarlyOffset,
+                dispSyncPresentTimeOffset, activeConfig->getVsyncPeriod());
     }
     result.append("\n");
 
diff --git a/services/surfaceflinger/VSyncModulator.h b/services/surfaceflinger/VSyncModulator.h
index d526313..e071a59 100644
--- a/services/surfaceflinger/VSyncModulator.h
+++ b/services/surfaceflinger/VSyncModulator.h
@@ -36,6 +36,11 @@
 
 public:
 
+    struct Offsets {
+        nsecs_t sf;
+        nsecs_t app;
+    };
+
     enum TransactionStart {
         EARLY,
         NORMAL
@@ -43,21 +48,32 @@
 
     // Sets the phase offsets
     //
-    // early: the phase offset when waking up early. May be the same as late, in which case we don't
-    //        shift offsets.
-    // late: the regular sf phase offset.
-    void setPhaseOffsets(nsecs_t early, nsecs_t late) {
-        mEarlyPhaseOffset = early;
-        mLatePhaseOffset = late;
-        mPhaseOffset = late;
+    // sfEarly: The phase offset when waking up SF early, which happens when marking a transaction
+    //          as early. May be the same as late, in which case we don't shift offsets.
+    // sfEarlyGl: Like sfEarly, but only if we used GL composition. If we use both GL composition
+    //            and the transaction was marked as early, we'll use sfEarly.
+    // sfLate: The regular SF vsync phase offset.
+    // appEarly: Like sfEarly, but for the app-vsync
+    // appEarlyGl: Like sfEarlyGl, but for the app-vsync.
+    // appLate: The regular app vsync phase offset.
+    void setPhaseOffsets(Offsets early, Offsets earlyGl, Offsets late) {
+        mEarlyOffsets = early;
+        mEarlyGlOffsets = earlyGl;
+        mLateOffsets = late;
+        mOffsets = late;
     }
 
-    nsecs_t getEarlyPhaseOffset() const {
-        return mEarlyPhaseOffset;
+    Offsets getEarlyOffsets() const {
+        return mEarlyOffsets;
     }
 
-    void setEventThread(EventThread* eventThread) {
-        mEventThread = eventThread;
+    Offsets getEarlyGlOffsets() const {
+        return mEarlyGlOffsets;
+    }
+
+    void setEventThreads(EventThread* sfEventThread, EventThread* appEventThread) {
+        mSfEventThread = sfEventThread;
+        mAppEventThread = appEventThread;
     }
 
     void setTransactionStart(TransactionStart transactionStart) {
@@ -71,63 +87,70 @@
             return;
         }
         mTransactionStart = transactionStart;
-        updatePhaseOffsets();
+        updateOffsets();
     }
 
     void onTransactionHandled() {
         if (mTransactionStart == TransactionStart::NORMAL) return;
         mTransactionStart = TransactionStart::NORMAL;
-        updatePhaseOffsets();
+        updateOffsets();
     }
 
     void onRefreshed(bool usedRenderEngine) {
-        bool updatePhaseOffsetsNeeded = false;
+        bool updateOffsetsNeeded = false;
         if (mRemainingEarlyFrameCount > 0) {
             mRemainingEarlyFrameCount--;
-            updatePhaseOffsetsNeeded = true;
+            updateOffsetsNeeded = true;
         }
         if (usedRenderEngine != mLastFrameUsedRenderEngine) {
             mLastFrameUsedRenderEngine = usedRenderEngine;
-            updatePhaseOffsetsNeeded = true;
+            updateOffsetsNeeded = true;
         }
-        if (updatePhaseOffsetsNeeded) {
-            updatePhaseOffsets();
+        if (updateOffsetsNeeded) {
+            updateOffsets();
         }
     }
 
 private:
 
-    void updatePhaseOffsets() {
+    void updateOffsets() {
+        const Offsets desired = getOffsets();
+        const Offsets current = mOffsets;
 
-        // Do not change phase offsets if disabled.
-        if (mEarlyPhaseOffset == mLatePhaseOffset) return;
+        bool changed = false;
+        if (desired.sf != current.sf) {
+            mSfEventThread->setPhaseOffset(desired.sf);
+            changed = true;
+        }
+        if (desired.app != current.app) {
+            mAppEventThread->setPhaseOffset(desired.app);
+            changed = true;
+        }
 
-        if (shouldUseEarlyOffset()) {
-            if (mPhaseOffset != mEarlyPhaseOffset) {
-                if (mEventThread) {
-                    mEventThread->setPhaseOffset(mEarlyPhaseOffset);
-                }
-                mPhaseOffset = mEarlyPhaseOffset;
-            }
-        } else {
-            if (mPhaseOffset != mLatePhaseOffset) {
-                if (mEventThread) {
-                    mEventThread->setPhaseOffset(mLatePhaseOffset);
-                }
-                mPhaseOffset = mLatePhaseOffset;
-            }
+        if (changed) {
+            mOffsets = desired;
         }
     }
 
-    bool shouldUseEarlyOffset() {
-        return mTransactionStart == TransactionStart::EARLY || mLastFrameUsedRenderEngine
-                || mRemainingEarlyFrameCount > 0;
+    Offsets getOffsets() {
+        if (mTransactionStart == TransactionStart::EARLY || mRemainingEarlyFrameCount > 0) {
+            return mEarlyOffsets;
+        } else if (mLastFrameUsedRenderEngine) {
+            return mEarlyGlOffsets;
+        } else {
+            return mLateOffsets;
+        }
     }
 
-    nsecs_t mLatePhaseOffset = 0;
-    nsecs_t mEarlyPhaseOffset = 0;
-    EventThread* mEventThread = nullptr;
-    std::atomic<nsecs_t> mPhaseOffset = 0;
+    Offsets mLateOffsets;
+    Offsets mEarlyOffsets;
+    Offsets mEarlyGlOffsets;
+
+    EventThread* mSfEventThread = nullptr;
+    EventThread* mAppEventThread = nullptr;
+
+    std::atomic<Offsets> mOffsets;
+
     std::atomic<TransactionStart> mTransactionStart = TransactionStart::NORMAL;
     std::atomic<bool> mLastFrameUsedRenderEngine = false;
     std::atomic<int> mRemainingEarlyFrameCount = 0;