Fiddling with threading bugs (both Qemu and Bochs hate atm)

[tpg/acess2.git] / Kernel / threads.c

diff --git a/Kernel/threads.c b/Kernel/threads.c
index 9fd052b..ab31e12 100644 (file)
--- a/Kernel/threads.c
+++ b/Kernel/threads.c
@@ -91,7 +91,7 @@ void Threads_Init(void)
        // Create Initial Task
        gActiveThreads = &gThreadZero;
        gAllThreads = &gThreadZero;
-       //giFreeTickets = gThreadZero.NumTickets;
+       //giFreeTickets = gThreadZero.NumTickets;       // Not needed, as ThreadZero is running
        giNumActiveThreads = 1;
                
        Proc_Start();
@@ -385,7 +385,7 @@ void Threads_Kill(tThread *Thread, int Status)
        tThread *prev;
        tMsg    *msg;
        
-       // Kill all children
+       // TODO: Kill all children
        #if 0
        {
                tThread *child;
@@ -411,8 +411,8 @@ void Threads_Kill(tThread *Thread, int Status)
        prev = Threads_int_GetPrev( &gActiveThreads, Thread );
        if(!prev) {
                Warning("Proc_Exit - Current thread is not on the active queue");
-               SHORTREL( &Thread->IsLocked );
                SHORTREL( &glThreadListLock );
+               SHORTREL( &Thread->IsLocked );
                return;
        }
        
@@ -510,7 +510,7 @@ void Threads_Sleep(void)
  * \brief Wakes a sleeping/waiting thread up
  * \param Thread       Thread to wake
  * \return Boolean Failure (Returns ERRNO)
- * \note Should be called with the scheduler lock held
+ * \warning This should ONLY be called with task switches disabled
  */
 int Threads_Wake(tThread *Thread)
 {
@@ -525,19 +525,22 @@ int Threads_Wake(tThread *Thread)
                Log("Thread_Wake: Waking awake thread (%i)", Thread->TID);
                return -EALREADY;
        
-       case THREAD_STAT_SLEEPING:      // TODO: Comment better
+       case THREAD_STAT_SLEEPING:
                // Remove from sleeping queue
                prev = Threads_int_GetPrev(&gSleepingThreads, Thread);
                prev->Next = Thread->Next;
+               
                // Add to active queue
                Thread->Next = gActiveThreads;
                gActiveThreads = Thread;
+               
                // Update bookkeeping
                giNumActiveThreads ++;
                giFreeTickets += Thread->NumTickets;
                #if DEBUG_TRACE_TICKETS
                Log("Threads_Wake: new giFreeTickets = %i", giFreeTickets);
                #endif
+               
                Thread->CurCPU = -1;
                Thread->Status = THREAD_STAT_ACTIVE;
                #if DEBUG_TRACE_STATE
@@ -573,6 +576,7 @@ int Threads_WakeTID(tTID TID)
        SHORTLOCK( &glThreadListLock );
        ret = Threads_Wake( thread );
        SHORTREL( &glThreadListLock );
+       //Log_Debug("Threads", "TID %i woke %i (%p)", Threads_GetTID(), TID, thread);
        return ret;
 }
 
@@ -714,7 +718,8 @@ void Threads_Dump(void)
        {
                Log(" %i (%i) - %s (CPU %i)",
                        thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
-               Log("  State: %i", thread->Status);
+               if(thread->Status != THREAD_STAT_ACTIVE)
+                       Log("  ERROR State (%i) != THREAD_STAT_ACTIVE (%i)", thread->Status, THREAD_STAT_ACTIVE);
                Log("  %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum);
                Log("  KStack 0x%x", thread->KernelStack);
        }
@@ -724,7 +729,7 @@ void Threads_Dump(void)
        {
                Log(" %i (%i) - %s (CPU %i)",
                        thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
-               Log("  State: %i", thread->Status);
+               Log("  State %i", thread->Status);
                Log("  %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum);
                Log("  KStack 0x%x", thread->KernelStack);
        }
@@ -746,6 +751,7 @@ tThread *Threads_GetNextToRun(int CPU, tThread *Last)
        SHORTLOCK( &glThreadListLock );
        
        // Clear Delete Queue
+       // - I should probably put this in a worker thread to avoid calling free() in the scheduler
        while(gDeleteThreads)
        {
                thread = gDeleteThreads->Next;
@@ -795,14 +801,14 @@ tThread *Threads_GetNextToRun(int CPU, tThread *Last)
                }
                #if DEBUG_TRACE_TICKETS
                else
-                       LogF(" %p (%s)->Status = %i\n", Last, Last->ThreadName, Last->Status);
+                       LogF(" %p (%s)->Status = %i (Released)\n", Last, Last->ThreadName, Last->Status);
                #endif
                Last->CurCPU = -1;
        }
        
        #if 1
        number = 0;
-       for(thread=gActiveThreads;thread;thread=thread->Next) {
+       for(thread = gActiveThreads; thread; thread = thread->Next) {
                if(thread->CurCPU >= 0) continue;
                number += thread->NumTickets;
        }
@@ -907,7 +913,7 @@ void Mutex_Acquire(tMutex *Mutex)
                }
                SHORTREL( &glThreadListLock );
                SHORTREL( &Mutex->Protector );
-               while(us->Status == THREAD_STAT_OFFSLEEP)       HALT();
+               while(us->Status == THREAD_STAT_OFFSLEEP)       Threads_Yield();
                // We're only woken when we get the lock
        }
        // Ooh, let's take it!