Fixed a small threading issue introduced by r6933 causing savestates to always freeze, thanks to artart78 for pinpointing the issue.

Properly pause the core when saving/loading savestates, previously we used PowerPC::Pause() and Start() which only update the state but doesn't properly set m_StepEvent and caused random hangs.
Fixed hang when creating a savestate while the game was paused or in Frame Advance mode, now the thing works (just remember to press play duh).

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@6992 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/Core/Src/Core.cpp

@@ -163,7 +163,7 @@ bool isRunning()
 
 bool IsRunningInCurrentThread()
 {
-	return isRunning() && ((cpuThread.joinable()) || cpuThread.get_id() == std::this_thread::get_id());
+	return isRunning() && ((!cpuThread.joinable()) || cpuThread.get_id() == std::this_thread::get_id());
 }
 
 // This is called from the GUI thread. See the booting call schedule in

Source/Core/Core/Src/CoreTiming.cpp

@@ -68,7 +68,7 @@ u64 fakeDecStartTicks;
 u64 fakeTBStartValue;
 u64 fakeTBStartTicks;
 
-Common::CriticalSection externalEventSection;
+static Common::CriticalSection externalEventSection;
 
 void (*advanceCallback)(int cyclesExecuted) = NULL;
 

Source/Core/Core/Src/State.cpp

@@ -27,7 +27,7 @@
 #include "HW/Wiimote.h"
 #include "HW/DSP.h"
 #include "HW/HW.h"
-#include "PowerPC/PowerPC.h"
+#include "HW/CPU.h"
 #include "PowerPC/JitCommon/JitBase.h"
 
 #include "PluginManager.h"
@@ -93,6 +93,7 @@ void DoState(PointerWrap &p)
 
 	if (Core::g_CoreStartupParameter.bWii)
 		Wiimote::DoState(p.GetPPtr(), p.GetMode());
+
 	PowerPC::DoState(p);
 	HW::DoState(p);
 	CoreTiming::DoState(p);
@@ -170,6 +171,9 @@ void CompressAndDumpState(saveStruct* saveArg)
 
 	delete saveArg;
 
+	// For easy debugging
+	Common::SetCurrentThreadName("SaveState thread");
+
 	// Moving to last overwritten save-state
 	if (File::Exists(cur_filename.c_str()))
 	{
@@ -233,8 +237,8 @@ void CompressAndDumpState(saveStruct* saveArg)
 
 void SaveStateCallback(u64 userdata, int cyclesLate)
 {
-	// Stop the clock while we save the state
-	PowerPC::Pause();
+	// Pause the core while we save the state
+	CCPU::EnableStepping(true);
 
 	// Wait for the other threaded sub-systems to stop too
 	SLEEP(100);
@@ -264,16 +268,16 @@ void SaveStateCallback(u64 userdata, int cyclesLate)
 
 	saveThread = std::thread(CompressAndDumpState, saveData);
 
-	// Resume the clock
-	PowerPC::Start();
+	// Resume the core and disable stepping
+	CCPU::EnableStepping(false);
 }
 
 void LoadStateCallback(u64 userdata, int cyclesLate)
 {
 	bool bCompressedState;
 
-	// Stop the clock while we load the state
-	PowerPC::Pause();
+	// Stop the core while we load the state
+	CCPU::EnableStepping(true);
 
 	// Wait for the other threaded sub-systems to stop too
 	SLEEP(100);
@@ -295,7 +299,7 @@ void LoadStateCallback(u64 userdata, int cyclesLate)
 	{
 		Core::DisplayMessage("State not found", 2000);
 		// Resume the clock
-		PowerPC::Start();
+		CCPU::EnableStepping(false);
 		return;
 	}
 
@@ -314,7 +318,7 @@ void LoadStateCallback(u64 userdata, int cyclesLate)
 
 		fclose(f);
 		// Resume the clock
-		PowerPC::Start();
+		CCPU::EnableStepping(false);
 		return;
 	}
 
@@ -330,7 +334,7 @@ void LoadStateCallback(u64 userdata, int cyclesLate)
 		{
 			PanicAlertT("Error allocating buffer");
 			// Resume the clock
-			PowerPC::Start();
+			CCPU::EnableStepping(false);
 			return;
 		}
 		while (true)
@@ -351,7 +355,7 @@ void LoadStateCallback(u64 userdata, int cyclesLate)
 				fclose(f);
 				delete[] buffer;
 				// Resume the clock
-				PowerPC::Start();
+				CCPU::EnableStepping(false);
 				return;
 			}
 	
@@ -388,7 +392,7 @@ void LoadStateCallback(u64 userdata, int cyclesLate)
 	state_op_in_progress = false;
 
 	// Resume the clock
-	PowerPC::Start();
+	CCPU::EnableStepping(false);
 }
 
 void VerifyStateCallback(u64 userdata, int cyclesLate)

Source/Core/VideoCommon/Src/Fifo.cpp

@@ -34,7 +34,6 @@ namespace
 static volatile bool fifoStateRun = false;
 static volatile bool EmuRunning = false;
 static u8 *videoBuffer;
-static Common::EventEx fifo_run_event;
 // STATE_TO_SAVE
 static int size = 0;
 }  // namespace
@@ -55,14 +54,12 @@ void Fifo_DoState(PointerWrap &p)
 void Fifo_Init()
 {
     videoBuffer = (u8*)AllocateMemoryPages(FIFO_SIZE);
-	fifo_run_event.Init();
 	fifoStateRun = false;
 }
 
 void Fifo_Shutdown()
 {
 	if (fifoStateRun) PanicAlert("Fifo shutting down while active");
-	fifo_run_event.Shutdown();
     FreeMemoryPages(videoBuffer, FIFO_SIZE);
 }
 
@@ -89,6 +86,7 @@ void Fifo_SetRendering(bool enabled)
 void Fifo_ExitLoop()
 {
 	Fifo_ExitLoopNonBlocking();
+	EmuRunning = true;
 }
 
 // May be executed from any thread, even the graphics thread.
@@ -100,14 +98,12 @@ void Fifo_ExitLoopNonBlocking()
 	CommandProcessor::SetFifoIdleFromVideoPlugin();
 	// Terminate GPU thread loop
 	fifoStateRun = false;
-	fifo_run_event.Set();
+	EmuRunning = true;
 }
 
 void Fifo_RunLoop(bool run)
 {
 	EmuRunning = run;
-	if (run)
-		fifo_run_event.Set();
 }
 
 // Description: Fifo_EnterLoop() sends data through this function.
@@ -164,8 +160,8 @@ void Fifo_EnterLoop(const SVideoInitialize &video_initialize)
 
 			if (!fifoStateRun) break;
 
-			
 			CommandProcessor::FifoCriticalEnter();
+
 			// Create pointer to video data and send it to the VideoPlugin
 			u32 readPtr = _fifo.CPReadPointer;
 			u8 *uData = video_initialize.pGetMemoryPointer(readPtr);
@@ -191,22 +187,28 @@ void Fifo_EnterLoop(const SVideoInitialize &video_initialize)
 			CommandProcessor::SetStatus();
 
 			CommandProcessor::FifoCriticalLeave();
-
-			// Those two are pretty important and must be called in the FIFO Loop.
-			// If we don't, s_swapRequested (OGL only) or s_efbAccessRequested won't be set to false
+		
+			// This call is pretty important in DualCore mode and must be called in the FIFO Loop.
+			// If we don't, s_swapRequested or s_efbAccessRequested won't be set to false
 			// leading the CPU thread to wait in Video_BeginField or Video_AccessEFB thus slowing things down.
-			
-			VideoFifo_CheckAsyncRequest();
-									
+			VideoFifo_CheckAsyncRequest();					
 		}
 
 		CommandProcessor::isFifoBusy = false;
-		
 		CommandProcessor::SetFifoIdleFromVideoPlugin();
+
 		if (EmuRunning)
 			Common::YieldCPU();
 		else
-			fifo_run_event.MsgWait();
+		{
+			// While the emu is paused, we still handle async request such as Savestates then sleep.
+			while (!EmuRunning)
+			{
+				video_initialize.pPeekMessages();
+				VideoFifo_CheckAsyncRequest();
+				Common::SleepCurrentThread(10);
+			}
+		}
 	}
 }
 

Source/Core/VideoCommon/Src/MainBase.cpp

@@ -170,7 +170,8 @@ static volatile struct
 	int mode;
 } s_doStateArgs;
 
-// Run from the GPU thread on X11, CPU thread on the rest
+// Depending on the threading mode (DC/SC) this can be called 
+// from either the GPU thread or the CPU thread
 static void check_DoState() {
 	if (Common::AtomicLoadAcquire(s_doStateRequested))
 	{
@@ -194,7 +195,7 @@ static void check_DoState() {
 	}
 }
 
-// Run from the CPU thread
+// Run from the GUI thread
 void DoState(unsigned char **ptr, int mode)
 {
 	s_doStateArgs.ptr = ptr;
@@ -207,7 +208,7 @@ void DoState(unsigned char **ptr, int mode)
 			Common::YieldCPU();
 	}
 	else
-	check_DoState();
+		check_DoState();
 }
 
 void VideoFifo_CheckAsyncRequest()