Io: Change async thread priority if running.

Really thought I'd already done this, must've made a mistake...
Fixes #12400.

Core/HLE/HLEHelperThread.cpp

@@ -87,6 +87,10 @@ bool HLEHelperThread::Stopped() {
 	return KernelIsThreadDormant(id_);
 }
 
+void HLEHelperThread::ChangePriority(u32 prio) {
+	KernelChangeThreadPriority(id_, prio);
+}
+
 void HLEHelperThread::Forget() {
 	id_ = 0;
 	entry_ = 0;

Core/HLE/HLEHelperThread.h

@@ -32,6 +32,7 @@ public:
 	void Start(u32 a0, u32 a1);
 	void Terminate();
 	bool Stopped();
+	void ChangePriority(u32 prio);
 
 	// For savestates.
 	void Forget();

Core/HLE/sceIo.cpp

@@ -1973,6 +1973,10 @@ static int sceIoChangeAsyncPriority(int id, int priority) {
 		return hleLogError(SCEIO, error, "bad file descriptor");
 	}
 
+	if (asyncThreads[id] && !asyncThreads[id]->Stopped()) {
+		asyncThreads[id]->ChangePriority(priority);
+	}
+
 	asyncParams[id].priority = priority;
 	return hleLogSuccessI(SCEIO, 0);
 }

Core/HLE/sceKernelThread.cpp

@@ -2418,6 +2418,28 @@ int sceKernelChangeCurrentThreadAttr(u32 clearAttr, u32 setAttr) {
 	return hleLogSuccessI(SCEKERNEL, 0);
 }
 
+// Assumes validated parameters.
+bool KernelChangeThreadPriority(SceUID threadID, int priority) {
+	u32 error;
+	Thread *thread = kernelObjects.Get<Thread>(threadID, error);
+	if (thread) {
+		int old = thread->nt.currentPriority;
+		threadReadyQueue.remove(old, threadID);
+
+		thread->nt.currentPriority = priority;
+		threadReadyQueue.prepare(thread->nt.currentPriority);
+		if (thread->isRunning()) {
+			thread->nt.status = (thread->nt.status & ~THREADSTATUS_RUNNING) | THREADSTATUS_READY;
+		}
+		if (thread->isReady()) {
+			threadReadyQueue.push_back(thread->nt.currentPriority, threadID);
+		}
+		return true;
+	} else {
+		return false;
+	}
+}
+
 int sceKernelChangeThreadPriority(SceUID threadID, int priority) {
 	if (threadID == 0) {
 		threadID = __KernelGetCurThread();
@@ -2444,17 +2466,7 @@ int sceKernelChangeThreadPriority(SceUID threadID, int priority) {
 			return hleLogError(SCEKERNEL, SCE_KERNEL_ERROR_ILLEGAL_PRIORITY, "bogus priority");
 		}
 
-		int old = thread->nt.currentPriority;
+		KernelChangeThreadPriority(threadID, priority);
-		threadReadyQueue.remove(old, threadID);
-
-		thread->nt.currentPriority = priority;
-		threadReadyQueue.prepare(thread->nt.currentPriority);
-		if (thread->isRunning()) {
-			thread->nt.status = (thread->nt.status & ~THREADSTATUS_RUNNING) | THREADSTATUS_READY;
-		}
-		if (thread->isReady()) {
-			threadReadyQueue.push_back(thread->nt.currentPriority, threadID);
-		}
 
 		hleEatCycles(450);
 		hleReSchedule("change thread priority");

Core/HLE/sceKernelThread.h

@@ -162,6 +162,7 @@ KernelObject *__KernelCallbackObject();
 void __KernelScheduleWakeup(int threadnumber, s64 usFromNow);
 SceUID __KernelGetCurThread();
 int KernelCurThreadPriority();
+bool KernelChangeThreadPriority(SceUID threadID, int priority);
 u32 __KernelGetCurThreadStack();
 u32 __KernelGetCurThreadStackStart();
 const char *__KernelGetThreadName(SceUID threadID);