scheduler: Allow calling UpdatePriority() for disabled CPU

src/system/kernel/scheduler/scheduler.cpp

@@ -501,10 +501,9 @@ reschedule(int32 nextState)
 	nextThread->state = B_THREAD_RUNNING;
 
 	// update CPU heap
-	if (!gCPU[thisCPU].disabled) {
-		SpinLocker coreLocker(core->fCPULock);
-		cpu->UpdatePriority(nextThreadData->GetEffectivePriority());
-	}
+	SpinLocker coreLocker(core->fCPULock);
+	cpu->UpdatePriority(nextThreadData->GetEffectivePriority());
+	coreLocker.Unlock();
 
 	// track kernel time (user time is tracked in thread_at_kernel_entry())
 	update_thread_times(oldThread, nextThread);
@@ -637,8 +636,6 @@ scheduler_set_cpu_enabled(int32 cpuID, bool enabled)
 
 	InterruptsBigSchedulerLocker _;
 
-	gCPU[cpuID].disabled = !enabled;
-
 	gCurrentMode->set_cpu_enabled(cpuID, enabled);
 
 	CPUEntry* cpu = &gCPUEntries[cpuID];
@@ -654,6 +651,8 @@ scheduler_set_cpu_enabled(int32 cpuID, bool enabled)
 		core->fCPUCount--;
 	}
 
+	gCPU[cpuID].disabled = !enabled;
+
 	if (core->fCPUCount == 0) {
 		// core has been disabled
 		ASSERT(!enabled);

src/system/kernel/scheduler/scheduler_cpu.cpp

@@ -53,6 +53,9 @@ CPUEntry::CPUEntry()
 void
 CPUEntry::UpdatePriority(int32 priority)
 {
+	if (gCPU[fCPUNumber].disabled)
+		return;
+
 	int32 corePriority = CPUPriorityHeap::GetKey(fCore->fCPUHeap.PeekMaximum());
 	fCore->fCPUHeap.ModifyKey(this, priority);