Merge #4627

4627: Try to improve macos perf r=Jupeyy a=def-

`@Jupeyy` didn't work, I thought maybe it's because it uses the E cores, not P cores.

## Checklist

- [ ] Tested the change ingame
- [ ] Provided screenshots if it is a visual change
- [ ] Tested in combination with possibly related configuration options
- [ ] Written a unit test if it works standalone, system.c especially
- [ ] Considered possible null pointers and out of bounds array indexing
- [ ] Changed no physics that affect existing maps
- [ ] Tested the change with [ASan+UBSan or valgrind's memcheck](https://github.com/ddnet/ddnet/#using-addresssanitizer--undefinedbehavioursanitizer-or-valgrinds-memcheck) (optional)


Co-authored-by: Dennis Felsing <dennis@felsin9.de>

other/bundle/client/Info.plist.in

@@ -22,5 +22,7 @@
 		<true/>
 		<key>NSPrefersDisplaySafeAreaCompatibilityMode</key>
 		<true/>
+		<key>NSQualityOfService</key>
+		<string>NSQualityOfServiceUserInteractive</string>
 	</dict>
 </plist>

src/base/system.cpp

@@ -772,7 +772,12 @@ void *thread_init(void (*threadfunc)(void *), void *u, const char *name)
 #if defined(CONF_FAMILY_UNIX)
 	{
 		pthread_t id;
-		int result = pthread_create(&id, NULL, thread_run, data);
+		pthread_attr_t attr;
+		pthread_attr_init(&attr);
+#if defined(CONF_PLATFORM_MACOS)
+		pthread_attr_set_qos_class_np(&attr, QOS_CLASS_USER_INTERACTIVE, 0);
+#endif
+		int result = pthread_create(&id, &attr, thread_run, data);
 		if(result != 0)
 		{
 			dbg_msg("thread", "creating %s thread failed: %d", name, result);

src/engine/client/backend_sdl.cpp

@@ -56,24 +56,25 @@ int putenv(const char *);
 
 // ------------ CGraphicsBackend_Threaded
 
-void CGraphicsBackend_Threaded::ThreadFunc()
+void CGraphicsBackend_Threaded::ThreadFunc(void *pUser)
 {
-	std::unique_lock<std::mutex> Lock(m_BufferSwapMutex);
+	auto *pSelf = (CGraphicsBackend_Threaded *)pUser;
+	std::unique_lock<std::mutex> Lock(pSelf->m_BufferSwapMutex);
 	// notify, that the thread started
-	m_BufferDoneCond.notify_all();
-	while(!m_Shutdown)
+	pSelf->m_BufferDoneCond.notify_all();
+	while(!pSelf->m_Shutdown)
 	{
-		m_BufferSwapCond.wait(Lock);
-		if(m_pBuffer)
+		pSelf->m_BufferSwapCond.wait(Lock);
+		if(pSelf->m_pBuffer)
 		{
 #ifdef CONF_PLATFORM_MACOS
 			CAutoreleasePool AutoreleasePool;
 #endif
-			m_pProcessor->RunBuffer(m_pBuffer);
+			pSelf->m_pProcessor->RunBuffer(pSelf->m_pBuffer);
 
-			m_pBuffer = nullptr;
-			m_BufferInProcess.store(false, std::memory_order_relaxed);
-			m_BufferDoneCond.notify_all();
+			pSelf->m_pBuffer = nullptr;
+			pSelf->m_BufferInProcess.store(false, std::memory_order_relaxed);
+			pSelf->m_BufferDoneCond.notify_all();
 		}
 #if defined(CONF_VIDEORECORDER)
 		if(IVideo::Current())
@@ -94,7 +95,7 @@ void CGraphicsBackend_Threaded::StartProcessor(ICommandProcessor *pProcessor)
 	m_Shutdown = false;
 	m_pProcessor = pProcessor;
 	std::unique_lock<std::mutex> Lock(m_BufferSwapMutex);
-	m_Thread = std::thread([&]() { ThreadFunc(); });
+	m_Thread = thread_init(ThreadFunc, this, "Graphics thread");
 	// wait for the thread to start
 	m_BufferDoneCond.wait(Lock);
 }
@@ -106,7 +107,7 @@ void CGraphicsBackend_Threaded::StopProcessor()
 		std::unique_lock<std::mutex> Lock(m_BufferSwapMutex);
 		m_BufferSwapCond.notify_all();
 	}
-	m_Thread.join();
+	thread_wait(m_Thread);
 }
 
 void CGraphicsBackend_Threaded::RunBuffer(CCommandBuffer *pBuffer)

src/engine/client/backend_sdl.h

@@ -73,9 +73,9 @@ private:
 	CCommandBuffer *m_pBuffer;
 	std::atomic_bool m_Shutdown;
 	std::atomic_bool m_BufferInProcess;
-	std::thread m_Thread;
+	void *m_Thread;
 
-	void ThreadFunc();
+	static void ThreadFunc(void *pUser);
 };
 
 // takes care of implementation independent operations