UI: Remove locks in event dispatching

hrydgard · Nov 11, 2023 · 0c7b42b · 0c7b42b
1 parent e0c0cb9
commit 0c7b42b
Showing 1 changed file with 5 additions and 27 deletions.
diff --git a/Common/UI/Root.cpp b/Common/UI/Root.cpp
@@ -1,5 +1,3 @@
-#include <atomic>
-#include <mutex>
 #include <deque>
 
 #include "ppsspp_config.h"
@@ -12,14 +10,12 @@
 
 namespace UI {
 
-static std::mutex focusLock;
 static std::vector<int> focusMoves;
 extern bool focusForced;
 
 static View *focusedView;
 static bool focusMovementEnabled;
 bool focusForced;
-static std::mutex eventMutex_;
 
 static std::function<void(UISound, float)> soundCallback;
 static bool soundEnabled = true;
@@ -29,39 +25,27 @@ struct DispatchQueueItem {
 	EventParams params;
 };
 
-std::atomic<bool> hasDispatchQueue;
 std::deque<DispatchQueueItem> g_dispatchQueue;
 
 void EventTriggered(Event *e, EventParams params) {
 	DispatchQueueItem item{ e, params };
-
-	std::unique_lock<std::mutex> guard(eventMutex_);
-	// Set before adding so we lock and check the added value.
-	hasDispatchQueue = true;
 	g_dispatchQueue.push_front(item);
 }
 
 void DispatchEvents() {
-	while (hasDispatchQueue) {
+	while (!g_dispatchQueue.empty()) {
 		DispatchQueueItem item;
-		{
-			std::unique_lock<std::mutex> guard(eventMutex_);
-			if (g_dispatchQueue.empty())
-				break;
-			item = g_dispatchQueue.back();
-			g_dispatchQueue.pop_back();
-			hasDispatchQueue = !g_dispatchQueue.empty();
-		}
+		if (g_dispatchQueue.empty())
+			break;
+		item = g_dispatchQueue.back();
+		g_dispatchQueue.pop_back();
 		if (item.e) {
 			item.e->Dispatch(item.params);
 		}
 	}
 }
 
 void RemoveQueuedEventsByView(View *view) {
-	if (!hasDispatchQueue)
-		return;
-	std::unique_lock<std::mutex> guard(eventMutex_);
 	for (auto it = g_dispatchQueue.begin(); it != g_dispatchQueue.end(); ) {
 		if (it->params.v == view) {
 			it = g_dispatchQueue.erase(it);
@@ -72,9 +56,6 @@ void RemoveQueuedEventsByView(View *view) {
 }
 
 void RemoveQueuedEventsByEvent(Event *event) {
-	if (!hasDispatchQueue)
-		return;
-	std::unique_lock<std::mutex> guard(eventMutex_);
 	for (auto it = g_dispatchQueue.begin(); it != g_dispatchQueue.end(); ) {
 		if (it->e == event) {
 			it = g_dispatchQueue.erase(it);
@@ -214,7 +195,6 @@ static KeyEventResult KeyEventToFocusMoves(const KeyInput &key) {
 			hk.deviceId = key.deviceId;
 			hk.triggerTime = time_now_d() + repeatDelay;
 
-			std::lock_guard<std::mutex> lock(focusLock);
 			// Check if the key is already held. If it is, ignore it. This is to avoid
 			// multiple key repeat mechanisms colliding.
 			if (heldKeys.find(hk) != heldKeys.end()) {
@@ -381,7 +361,6 @@ static void ProcessHeldKeys(ViewGroup *root) {
 			key.flags = KEY_DOWN;
 			KeyEvent(key, root);
 
-			std::lock_guard<std::mutex> lock(focusLock);
 			focusMoves.push_back(key.keyCode);
 
 			// Cannot modify the current item when looping over a set, so let's do this instead.
@@ -404,7 +383,6 @@ void UpdateViewHierarchy(ViewGroup *root) {
 	}
 
 	if (focusMoves.size()) {
-		std::lock_guard<std::mutex> lock(focusLock);
 		EnableFocusMovement(true);
 		if (!GetFocusedView()) {
 			// Find a view to focus.