nextWakeupTime should be the soonest possible time

When updating nextWakeupTime, it should always be set to the minimum of
the current value and the new value. This variable tracks when we are
going to wake up next. If we already made a decision earlier that we
need to wake up soon, the subsequent code should not change that
decision by postponing the wakeup.

Bug: 211379801
Test: TEST=inputflinger_tests; m $TEST && $ANDROID_HOST_OUT/nativetest64/$TEST/$TEST
Change-Id: Ib8771f7b27047d7aa98acd68db6d214d4c364b89

2 files changed, 17 insertions, 23 deletions

diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp
index ab815ea3ed..162a7bd6c5 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.cpp
+++ b/services/inputflinger/dispatcher/InputDispatcher.cpp
@@ -835,7 +835,7 @@ void InputDispatcher::dispatchOnce() {
         // Run a dispatch loop if there are no pending commands.
         // The dispatch loop might enqueue commands to run afterwards.
         if (!haveCommandsLocked()) {
-            dispatchOnceInnerLocked(&nextWakeupTime);
+            dispatchOnceInnerLocked(/*byref*/ nextWakeupTime);
         }
 
         // Run all pending commands if there are any.
@@ -942,7 +942,7 @@ std::chrono::nanoseconds InputDispatcher::getDispatchingTimeoutLocked(
     return DEFAULT_INPUT_DISPATCHING_TIMEOUT;
 }
 
-void InputDispatcher::dispatchOnceInnerLocked(nsecs_t* nextWakeupTime) {
+void InputDispatcher::dispatchOnceInnerLocked(nsecs_t& nextWakeupTime) {
     nsecs_t currentTime = now();
 
     // Reset the key repeat timer whenever normal dispatch is suspended while the
@@ -966,9 +966,7 @@ void InputDispatcher::dispatchOnceInnerLocked(nsecs_t* nextWakeupTime) {
     bool isAppSwitchDue;
     if (!REMOVE_APP_SWITCH_DROPS) {
         isAppSwitchDue = mAppSwitchDueTime <= currentTime;
-        if (mAppSwitchDueTime < *nextWakeupTime) {
-            *nextWakeupTime = mAppSwitchDueTime;
-        }
+        nextWakeupTime = std::min(nextWakeupTime, mAppSwitchDueTime);
     }
 
     // Ready to start a new event.
@@ -989,9 +987,7 @@ void InputDispatcher::dispatchOnceInnerLocked(nsecs_t* nextWakeupTime) {
                 if (currentTime >= mKeyRepeatState.nextRepeatTime) {
                     mPendingEvent = synthesizeKeyRepeatLocked(currentTime);
                 } else {
-                    if (mKeyRepeatState.nextRepeatTime < *nextWakeupTime) {
-                        *nextWakeupTime = mKeyRepeatState.nextRepeatTime;
-                    }
+                    nextWakeupTime = std::min(nextWakeupTime, mKeyRepeatState.nextRepeatTime);
                 }
             }
 
@@ -1157,7 +1153,7 @@ void InputDispatcher::dispatchOnceInnerLocked(nsecs_t* nextWakeupTime) {
         mLastDropReason = dropReason;
 
         releasePendingEventLocked();
-        *nextWakeupTime = LLONG_MIN; // force next poll to wake up immediately
+        nextWakeupTime = LLONG_MIN; // force next poll to wake up immediately
     }
 }
 
@@ -1749,7 +1745,7 @@ std::vector<InputTarget> InputDispatcher::getInputTargetsFromWindowHandlesLocked
 }
 
 bool InputDispatcher::dispatchKeyLocked(nsecs_t currentTime, std::shared_ptr<const KeyEntry> entry,
-                                        DropReason* dropReason, nsecs_t* nextWakeupTime) {
+                                        DropReason* dropReason, nsecs_t& nextWakeupTime) {
     // Preprocessing.
     if (!entry->dispatchInProgress) {
         if (entry->repeatCount == 0 && entry->action == AKEY_EVENT_ACTION_DOWN &&
@@ -1800,9 +1796,7 @@ bool InputDispatcher::dispatchKeyLocked(nsecs_t currentTime, std::shared_ptr<con
     // Handle case where the policy asked us to try again later last time.
     if (entry->interceptKeyResult == KeyEntry::InterceptKeyResult::TRY_AGAIN_LATER) {
         if (currentTime < entry->interceptKeyWakeupTime) {
-            if (entry->interceptKeyWakeupTime < *nextWakeupTime) {
-                *nextWakeupTime = entry->interceptKeyWakeupTime;
-            }
+            nextWakeupTime = std::min(nextWakeupTime, entry->interceptKeyWakeupTime);
             return false; // wait until next wakeup
         }
         entry->interceptKeyResult = KeyEntry::InterceptKeyResult::UNKNOWN;
@@ -1882,7 +1876,7 @@ void InputDispatcher::logOutboundKeyDetails(const char* prefix, const KeyEntry&
 
 void InputDispatcher::dispatchSensorLocked(nsecs_t currentTime,
                                            const std::shared_ptr<const SensorEntry>& entry,
-                                           DropReason* dropReason, nsecs_t* nextWakeupTime) {
+                                           DropReason* dropReason, nsecs_t& nextWakeupTime) {
     if (DEBUG_OUTBOUND_EVENT_DETAILS) {
         ALOGD("notifySensorEvent eventTime=%" PRId64 ", hwTimestamp=%" PRId64 ", deviceId=%d, "
               "source=0x%x, sensorType=%s",
@@ -1922,7 +1916,7 @@ bool InputDispatcher::flushSensor(int deviceId, InputDeviceSensorType sensorType
 
 bool InputDispatcher::dispatchMotionLocked(nsecs_t currentTime,
                                            std::shared_ptr<const MotionEntry> entry,
-                                           DropReason* dropReason, nsecs_t* nextWakeupTime) {
+                                           DropReason* dropReason, nsecs_t& nextWakeupTime) {
     ATRACE_CALL();
     // Preprocessing.
     if (!entry->dispatchInProgress) {
@@ -2167,7 +2161,7 @@ bool InputDispatcher::shouldWaitToSendKeyLocked(nsecs_t currentTime,
 }
 
 sp<WindowInfoHandle> InputDispatcher::findFocusedWindowTargetLocked(
-        nsecs_t currentTime, const EventEntry& entry, nsecs_t* nextWakeupTime,
+        nsecs_t currentTime, const EventEntry& entry, nsecs_t& nextWakeupTime,
         InputEventInjectionResult& outInjectionResult) {
     outInjectionResult = InputEventInjectionResult::FAILED; // Default result
 
@@ -2206,7 +2200,7 @@ sp<WindowInfoHandle> InputDispatcher::findFocusedWindowTargetLocked(
             ALOGW("Waiting because no window has focus but %s may eventually add a "
                   "window when it finishes starting up. Will wait for %" PRId64 "ms",
                   mAwaitedFocusedApplication->getName().c_str(), millis(timeout));
-            *nextWakeupTime = *mNoFocusedWindowTimeoutTime;
+            nextWakeupTime = std::min(nextWakeupTime, *mNoFocusedWindowTimeoutTime);
             outInjectionResult = InputEventInjectionResult::PENDING;
             return nullptr;
         } else if (currentTime > *mNoFocusedWindowTimeoutTime) {
@@ -2251,7 +2245,7 @@ sp<WindowInfoHandle> InputDispatcher::findFocusedWindowTargetLocked(
     // prior input events.
     if (entry.type == EventEntry::Type::KEY) {
         if (shouldWaitToSendKeyLocked(currentTime, focusedWindowHandle->getName().c_str())) {
-            *nextWakeupTime = *mKeyIsWaitingForEventsTimeout;
+            nextWakeupTime = std::min(nextWakeupTime, *mKeyIsWaitingForEventsTimeout);
             outInjectionResult = InputEventInjectionResult::PENDING;
             return nullptr;
         }
diff --git a/services/inputflinger/dispatcher/InputDispatcher.h b/services/inputflinger/dispatcher/InputDispatcher.h
index 010dbb28e4..3567288f1d 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.h
+++ b/services/inputflinger/dispatcher/InputDispatcher.h
@@ -209,7 +209,7 @@ private:
     // This method should only be called on the input dispatcher's own thread.
     void dispatchOnce();
 
-    void dispatchOnceInnerLocked(nsecs_t* nextWakeupTime) REQUIRES(mLock);
+    void dispatchOnceInnerLocked(nsecs_t& nextWakeupTime) REQUIRES(mLock);
 
     // Enqueues an inbound event.  Returns true if mLooper->wake() should be called.
     bool enqueueInboundEventLocked(std::unique_ptr<EventEntry> entry) REQUIRES(mLock);
@@ -435,9 +435,9 @@ private:
     bool dispatchDeviceResetLocked(nsecs_t currentTime, const DeviceResetEntry& entry)
             REQUIRES(mLock);
     bool dispatchKeyLocked(nsecs_t currentTime, std::shared_ptr<const KeyEntry> entry,
-                           DropReason* dropReason, nsecs_t* nextWakeupTime) REQUIRES(mLock);
+                           DropReason* dropReason, nsecs_t& nextWakeupTime) REQUIRES(mLock);
     bool dispatchMotionLocked(nsecs_t currentTime, std::shared_ptr<const MotionEntry> entry,
-                              DropReason* dropReason, nsecs_t* nextWakeupTime) REQUIRES(mLock);
+                              DropReason* dropReason, nsecs_t& nextWakeupTime) REQUIRES(mLock);
     void dispatchFocusLocked(nsecs_t currentTime, std::shared_ptr<const FocusEntry> entry)
             REQUIRES(mLock);
     void dispatchPointerCaptureChangedLocked(
@@ -449,7 +449,7 @@ private:
     void dispatchEventLocked(nsecs_t currentTime, std::shared_ptr<const EventEntry> entry,
                              const std::vector<InputTarget>& inputTargets) REQUIRES(mLock);
     void dispatchSensorLocked(nsecs_t currentTime, const std::shared_ptr<const SensorEntry>& entry,
-                              DropReason* dropReason, nsecs_t* nextWakeupTime) REQUIRES(mLock);
+                              DropReason* dropReason, nsecs_t& nextWakeupTime) REQUIRES(mLock);
     void dispatchDragLocked(nsecs_t currentTime, std::shared_ptr<const DragEntry> entry)
             REQUIRES(mLock);
     void logOutboundKeyDetails(const char* prefix, const KeyEntry& entry);
@@ -521,7 +521,7 @@ private:
 
     int32_t getTargetDisplayId(const EventEntry& entry);
     sp<android::gui::WindowInfoHandle> findFocusedWindowTargetLocked(
-            nsecs_t currentTime, const EventEntry& entry, nsecs_t* nextWakeupTime,
+            nsecs_t currentTime, const EventEntry& entry, nsecs_t& nextWakeupTime,
             android::os::InputEventInjectionResult& outInjectionResult) REQUIRES(mLock);
     std::vector<InputTarget> findTouchedWindowTargetsLocked(
             nsecs_t currentTime, const MotionEntry& entry,