From: John Hodge <tpg@portege.thepowersgang.com>
Date: Fri, 25 Sep 2009 02:13:28 +0000 (+0800)
Subject: Moved task selection to threads.c, fixed segfault in Proc_ChangeStacks
X-Git-Tag: rel0.06~524
X-Git-Url: https://git.ucc.asn.au/?a=commitdiff_plain;h=35e419b3110ef56ffdc3f16c1fc819874b888ba5;p=tpg%2Facess2.git

Moved task selection to threads.c, fixed segfault in Proc_ChangeStacks
---

diff --git a/Kernel/arch/x86/proc.c b/Kernel/arch/x86/proc.c
index 31eb0557..448eab27 100644
--- a/Kernel/arch/x86/proc.c
+++ b/Kernel/arch/x86/proc.c
@@ -27,6 +27,7 @@ extern int	giNumActiveThreads;
 extern tThread	*gActiveThreads;
 extern tThread	*gSleepingThreads;
 extern tThread	*gDeleteThreads;
+extern tThread	*Threads_GetNextToRun(int CPU);
 
 // === PROTOTYPES ===
 void	ArchThreads_Init();
@@ -174,7 +175,7 @@ void Proc_ChangeStack()
 		return;
 	}
 
-	curBase = gCurrentThread->KernelStack;
+	curBase = (Uint)&Kernel_Stack_Top;
 	
 	LOG("curBase = 0x%x, newBase = 0x%x", curBase, newBase);
 
@@ -292,58 +293,6 @@ int Proc_Clone(Uint *Err, Uint Flags)
 	return newThread->TID;
 }
 
-#if 0
-/**
- * \fn void Proc_SetSignalHandler(int Num, void *Handler)
- * \brief Sets the signal handler for a signal
- */
-void Proc_SetSignalHandler(int Num, void *Handler)
-{
-	if(Num < 0 || Num >= NSIG)	return;
-	
-	gCurrentThread->SignalHandlers[Num] = Handler;
-}
-
-/**
- * \fn void Proc_SendSignal(int TID, int Num)
- */
-void Proc_SendSignal(int TID, int Num)
-{
-	tThread	*thread = Proc_GetThread(TID);
-	void	*handler;
-	
-	if(!thread)	return ;
-	
-	handler = thread->SignalHandlers[Num];
-	
-	// Panic?
-	if(handler == SIG_ERR) {
-		Proc_Kill(TID);
-		return ;
-	}
-	// Dump Core?
-	if(handler == -2) {
-		Proc_Kill(TID);
-		return ;
-	}
-	// Ignore?
-	if(handler == -2)	return;
-	
-	// Check the type and handle if the thread is already in a signal
-	if(thread->CurSignal != 0) {
-		if(Num < _SIGTYPE_FATAL)
-			Proc_Kill(TID);
-		} else {
-			while(thread->CurSignal != 0)
-				Proc_Yield();
-		}
-	}
-	
-	//TODO: 
-}
-
-#endif
-
 /**
  * \fn Uint Proc_MakeUserStack()
  * \brief Creates a new user stack
@@ -475,7 +424,6 @@ int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
 void Proc_Scheduler(int CPU)
 {
 	Uint	esp, ebp, eip;
-	Uint	number, ticket;
 	tThread	*thread;
 	
 	// If the spinlock is set, let it complete
@@ -499,7 +447,7 @@ void Proc_Scheduler(int CPU)
 		return;
 	}
 	
-	// Reduce remaining quantum
+	// Reduce remaining quantum and continue timeslice if non-zero
 	if(gCurrentThread->Remaining--)	return;
 	// Reset quantum for next call
 	gCurrentThread->Remaining = gCurrentThread->Quantum;
@@ -515,34 +463,13 @@ void Proc_Scheduler(int CPU)
 	gCurrentThread->SavedState.EBP = ebp;
 	gCurrentThread->SavedState.EIP = eip;
 	
-	// Special case: 1 thread
-	if(giNumActiveThreads == 1)
-	{
-		// Check if a switch is needed (NumActive can be 1 after a sleep)
-		if(gActiveThreads == gCurrentThread)	return;
-		// Switch processes
-		gCurrentThread = gActiveThreads;
-		goto performSwitch;
-	}
-	
-	// Get the ticket number
-	ticket = number = rand() % giTotalTickets;
-	
-	// Find the next thread
-	for(thread=gActiveThreads;thread;thread=thread->Next)
-	{
-		if(thread->NumTickets > number)	break;
-		number -= thread->NumTickets;
-	}
+	// Get next thread
+	thread = Threads_GetNextToRun(CPU);
 	
 	// Error Check
-	if(thread == NULL)
-	{
-		number = 0;
-		for(thread=gActiveThreads;thread;thread=thread->Next)
-			number += thread->NumTickets;
-		Panic("Bookeeping Failed - giTotalTicketCount (%i) != true count (%i)",
-			giTotalTickets, number);
+	if(thread == NULL) {
+		Warning("Hmm... Threads_GetNextToRun returned NULL, I don't think this should happen.\n");
+		return;
 	}
 	
 	// Set current thread
@@ -551,9 +478,7 @@ void Proc_Scheduler(int CPU)
 	// Update Kernel Stack pointer
 	gTSSs[CPU].ESP0 = thread->KernelStack;
 	
-performSwitch:
 	// Set address space
-	//MM_SetCR3( gCurrentThread->CR3 );
 	__asm__ __volatile__ ("mov %0, %%cr3"::"a"(gCurrentThread->MemState.CR3));
 	// Switch threads
 	__asm__ __volatile__ (
diff --git a/Kernel/threads.c b/Kernel/threads.c
index fb14f4d7..27356613 100644
--- a/Kernel/threads.c
+++ b/Kernel/threads.c
@@ -405,6 +405,57 @@ void Threads_Wake(tThread *Thread)
 	}
 }
 
+#if 0
+/**
+ * \fn void Threads_SetSignalHandler(int Num, void *Handler)
+ * \brief Sets the signal handler for a signal
+ */
+void Threads_SetSignalHandler(int Num, void *Handler)
+{
+	if(Num < 0 || Num >= NSIG)	return;
+	
+	gCurrentThread->SignalHandlers[Num] = Handler;
+}
+
+/**
+ * \fn void Threads_SendSignal(int TID, int Num)
+ */
+void Threads_SendSignal(int TID, int Num)
+{
+	tThread	*thread = Proc_GetThread(TID);
+	void	*handler;
+	
+	if(!thread)	return ;
+	
+	handler = thread->SignalHandlers[Num];
+	
+	// Panic?
+	if(handler == SIG_ERR) {
+		Proc_Kill(TID);
+		return ;
+	}
+	// Dump Core?
+	if(handler == -2) {
+		Proc_Kill(TID);
+		return ;
+	}
+	// Ignore?
+	if(handler == -2)	return;
+	
+	// Check the type and handle if the thread is already in a signal
+	if(thread->CurSignal != 0) {
+		if(Num < _SIGTYPE_FATAL)
+			Proc_Kill(TID);
+		} else {
+			while(thread->CurSignal != 0)
+				Proc_Yield();
+		}
+	}
+	
+	//TODO: 
+}
+#endif
+
 // --- Process Structure Access Functions ---
 int Threads_GetPID()
 {
@@ -446,3 +497,42 @@ void Threads_Dump()
 		Log("  KStack 0x%x", thread->KernelStack);
 	}
 }
+
+/**
+ * \fn tThread *Threads_GetNextToRun(int CPU)
+ * \brief Gets the next thread to run
+ */
+tThread *Threads_GetNextToRun(int CPU)
+{
+	tThread	*thread;
+	 int	ticket;
+	 int	number;
+	
+	// Special case: 1 thread
+	if(giNumActiveThreads == 1)
+	{
+		return gActiveThreads;
+	}
+	
+	// Get the ticket number
+	ticket = number = rand() % giTotalTickets;
+	
+	// Find the next thread
+	for(thread=gActiveThreads;thread;thread=thread->Next)
+	{
+		if(thread->NumTickets > number)	break;
+		number -= thread->NumTickets;
+	}
+	
+	// Error Check
+	if(thread == NULL)
+	{
+		number = 0;
+		for(thread=gActiveThreads;thread;thread=thread->Next)
+			number += thread->NumTickets;
+		Panic("Bookeeping Failed - giTotalTicketCount (%i) != true count (%i)",
+			giTotalTickets, number);
+	}
+	
+	return thread;
+}