#include <acess.h>
#include <threads.h>
#include <errno.h>
+#include <semaphore.h>
// Configuration
#define DEBUG_TRACE_TICKETS 0 // Trace ticket counts
// === IMPORTS ===
extern void ArchThreads_Init(void);
-extern void Proc_Start(void);
-extern tThread *Proc_GetCurThread(void);
-extern int Proc_Clone(Uint *Err, Uint Flags);
extern void Proc_CallFaultHandler(tThread *Thread);
+extern int GetCPUNum(void);
// === PROTOTYPES ===
void Threads_Init(void);
- int Threads_SetName(char *NewName);
+#if 0
+ int Threads_SetName(const char *NewName);
+#endif
char *Threads_GetName(int ID);
+#if 0
void Threads_SetPriority(tThread *Thread, int Pri);
tThread *Threads_CloneTCB(Uint *Err, Uint Flags);
int Threads_WaitTID(int TID, int *status);
tThread *Threads_GetThread(Uint TID);
+#endif
void Threads_AddToDelete(tThread *Thread);
tThread *Threads_int_DelFromQueue(tThread **List, tThread *Thread);
+#if 0
void Threads_Exit(int TID, int Status);
void Threads_Kill(tThread *Thread, int Status);
void Threads_Yield(void);
int Threads_Wake(tThread *Thread);
void Threads_AddActive(tThread *Thread);
tThread *Threads_RemActive(void);
+#endif
+void Threads_Fault(int Num);
+void Threads_SegFault(tVAddr Addr);
+#if 0
int Threads_GetPID(void);
int Threads_GetTID(void);
tUID Threads_GetUID(void);
- int Threads_SetUID(Uint *Errno, tUID ID);
tGID Threads_GetGID(void);
+ int Threads_SetUID(Uint *Errno, tUID ID);
int Threads_SetGID(Uint *Errno, tUID ID);
+#endif
void Threads_Dump(void);
void Threads_DumpActive(void);
-void Mutex_Acquire(tMutex *Mutex);
+
+#if 0
+ int Mutex_Acquire(tMutex *Mutex);
void Mutex_Release(tMutex *Mutex);
int Mutex_IsLocked(tMutex *Mutex);
+#endif
// === GLOBALS ===
// -- Core Thread --
// Only used for the core kernel
tThread gThreadZero = {
Status: THREAD_STAT_ACTIVE, // Status
- ThreadName: "ThreadZero", // Name
+ ThreadName: (char*)"ThreadZero", // Name
Quantum: DEFAULT_QUANTUM, // Default Quantum
Remaining: DEFAULT_QUANTUM, // Current Quantum
Priority: DEFAULT_PRIORITY // Number of tickets
}
/**
- * \fn void Threads_SetName(char *NewName)
+ * \fn void Threads_SetName(const char *NewName)
* \brief Sets the current thread's name
* \param NewName New name for the thread
* \return Boolean Failure
*/
-int Threads_SetName(char *NewName)
+int Threads_SetName(const char *NewName)
{
tThread *cur = Proc_GetCurThread();
char *oldname = cur->ThreadName;
SHORTLOCK( &glThreadListLock );
new->GlobalPrev = NULL; // Protect against bugs
new->GlobalNext = gAllThreads;
+ gAllThreads->GlobalPrev = new;
+ gAllThreads = new;
+ SHORTREL( &glThreadListLock );
+
+ return new;
+}
+
+/**
+ * \fn tThread *Threads_CloneTCB(Uint *Err, Uint Flags)
+ * \brief Clone the TCB of the current thread
+ */
+tThread *Threads_CloneThreadZero(void)
+{
+ tThread *cur, *new;
+ int i;
+ cur = Proc_GetCurThread();
+
+ // Allocate and duplicate
+ new = malloc(sizeof(tThread));
+ if(new == NULL) {
+ return NULL;
+ }
+ memcpy(new, &gThreadZero, sizeof(tThread));
+
+ new->CurCPU = -1;
+ new->Next = NULL;
+ memset( &new->IsLocked, 0, sizeof(new->IsLocked));
+ new->Status = THREAD_STAT_PREINIT;
+ new->RetStatus = 0;
+
+ // Get Thread ID
+ new->TID = giNextTID++;
+ new->Parent = 0;
+
+ // Clone Name
+ new->ThreadName = NULL;
+
+ // Messages are not inherited
+ new->Messages = NULL;
+ new->LastMessage = NULL;
+
+ // Set State
+ new->Remaining = new->Quantum = cur->Quantum;
+ new->Priority = cur->Priority;
+
+ // Set Signal Handlers
+ new->CurFaultNum = 0;
+ new->FaultHandler = cur->FaultHandler;
+
+ for( i = 0; i < NUM_CFG_ENTRIES; i ++ )
+ {
+ switch(cCONFIG_TYPES[i])
+ {
+ default:
+ new->Config[i] = cur->Config[i];
+ break;
+ case CFGT_HEAPSTR:
+ if(cur->Config[i])
+ new->Config[i] = (Uint) strdup( (void*)cur->Config[i] );
+ else
+ new->Config[i] = 0;
+ break;
+ }
+ }
+
+ // Maintain a global list of threads
+ SHORTLOCK( &glThreadListLock );
+ new->GlobalPrev = NULL; // Protect against bugs
+ new->GlobalNext = gAllThreads;
+ gAllThreads->GlobalPrev = new;
gAllThreads = new;
SHORTREL( &glThreadListLock );
void Threads_Kill(tThread *Thread, int Status)
{
tMsg *msg;
+ int isCurThread = Thread == Proc_GetCurThread();
// TODO: Kill all children
- #if 0
+ #if 1
{
tThread *child;
// TODO: I should keep a .Parent pointer, and a .Children list
- for(child = gActiveThreads;
+ for(child = gAllThreads;
child;
- child = child->Next)
+ child = child->GlobalNext)
{
- if(child->PTID == Thread->TID)
+ if(child->Parent == Thread)
Threads_Kill(child, -1);
}
}
// Lock thread list
SHORTLOCK( &glThreadListLock );
- // Delete from active list
- #if SCHEDULER_TYPE == SCHED_RR_PRI
- if( !Threads_int_DelFromQueue( &gaActiveThreads[Thread->Priority], Thread ) )
- #else
- if( !Threads_int_DelFromQueue( &gActiveThreads, Thread ) )
- #endif
+ switch(Thread->Status)
{
- Warning("Proc_Exit - Current thread is not on the active queue");
+ case THREAD_STAT_PREINIT: // Only on main list
+ break;
+
+ // Currently active thread
+ case THREAD_STAT_ACTIVE:
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ if( Threads_int_DelFromQueue( &gaActiveThreads[Thread->Priority], Thread ) )
+ #else
+ if( Threads_int_DelFromQueue( &gActiveThreads, Thread ) )
+ #endif
+ {
+ // Ensure that we are not rescheduled
+ Thread->Remaining = 0; // Clear Remaining Quantum
+ Thread->Quantum = 0; // Clear Quantum to indicate dead thread
+
+ // Update bookkeeping
+ giNumActiveThreads --;
+ #if SCHEDULER_TYPE == SCHED_LOTTERY
+ if( Thread != Proc_GetCurThread() )
+ giFreeTickets -= caiTICKET_COUNTS[ Thread->Priority ];
+ #endif
+ }
+ else
+ {
+ Log_Warning("Threads",
+ "Threads_Kill - Thread %p(%i,%s) marked as active, but not on list",
+ Thread, Thread->TID, Thread->ThreadName
+ );
+ }
+ break;
+ // Kill it while it sleeps!
+ case THREAD_STAT_SLEEPING:
+ if( !Threads_int_DelFromQueue( &gSleepingThreads, Thread ) )
+ {
+ Log_Warning("Threads",
+ "Threads_Kill - Thread %p(%i,%s) marked as sleeping, but not on list",
+ Thread, Thread->TID, Thread->ThreadName
+ );
+ }
+ break;
+
+ // Brains!... You cannot kill
+ case THREAD_STAT_ZOMBIE:
+ Log_Warning("Threads", "Threads_Kill - Thread %p(%i,%s) is undead, you cannot kill it",
+ Thread, Thread->TID, Thread->ThreadName);
SHORTREL( &glThreadListLock );
SHORTREL( &Thread->IsLocked );
- return;
- }
-
- // Ensure that we are not rescheduled
- Thread->Remaining = 0; // Clear Remaining Quantum
- Thread->Quantum = 0; // Clear Quantum to indicate dead thread
+ return ;
- // Update bookkeeping
- giNumActiveThreads --;
- #if SCHEDULER_TYPE == SCHED_LOTTERY
- if( Thread != Proc_GetCurThread() )
- giFreeTickets -= caiTICKET_COUNTS[ Thread->Priority ];
- #endif
+ default:
+ Log_Warning("Threads", "Threads_Kill - BUG Un-checked status (%i)",
+ Thread->Status);
+ break;
+ }
// Save exit status
Thread->RetStatus = Status;
Threads_Wake( Thread->Parent );
}
- Log("Thread %i went *hurk* (%i)", Thread->TID, Thread->Status);
+ Log("Thread %i went *hurk* (%i)", Thread->TID, Status);
// Release spinlocks
SHORTREL( &glThreadListLock );
SHORTREL( &Thread->IsLocked ); // TODO: We may not actually be released...
// And, reschedule
- if(Status != -1) {
+ if(isCurThread) {
for( ;; )
HALT();
}
switch(Thread->Status)
{
case THREAD_STAT_ACTIVE:
- Log("Thread_Wake: Waking awake thread (%i)", Thread->TID);
+ Log("Threads_Wake - Waking awake thread (%i)", Thread->TID);
return -EALREADY;
case THREAD_STAT_SLEEPING:
return -EOK;
case THREAD_STAT_WAITING:
- Warning("Thread_Wake - Waiting threads are not currently supported");
+ Warning("Threads_Wake - Waiting threads are not currently supported");
return -ENOTIMPL;
case THREAD_STAT_DEAD:
- Warning("Thread_Wake - Attempt to wake dead thread (%i)", Thread->TID);
+ Warning("Threads_Wake - Attempt to wake dead thread (%i)", Thread->TID);
return -ENOTIMPL;
default:
- Warning("Thread_Wake - Unknown process status (%i)\n", Thread->Status);
+ Warning("Threads_Wake - Unknown process status (%i)\n", Thread->Status);
return -EINTERNAL;
}
}
{
SHORTLOCK( &glThreadListLock );
+ if( Thread->Status == THREAD_STAT_ACTIVE ) {
+ tThread *cur = Proc_GetCurThread();
+ Warning("WTF, CPU%i %p (%i %s) is adding %p (%i %s) when it is active",
+ GetCPUNum(), cur, cur->TID, cur->ThreadName, Thread, Thread->TID, Thread->ThreadName);
+ }
+
// Set state
Thread->Status = THREAD_STAT_ACTIVE;
Thread->CurCPU = -1;
#if SCHEDULER_TYPE == SCHED_LOTTERY
giFreeTickets += caiTICKET_COUNTS[ Thread->Priority ];
# if DEBUG_TRACE_TICKETS
- Log("Threads_AddActive: %p %i (%s) added, new giFreeTickets = %i",
- Thread, Thread->TID, Thread->ThreadName, giFreeTickets);
+ Log("Threads_AddActive: CPU%i %p %i (%s) added, new giFreeTickets = %i",
+ GetCPUNum(), Thread, Thread->TID, Thread->ThreadName, giFreeTickets);
# endif
#endif
// no need to decrement tickets, scheduler did it for us
#if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS
- Log("Threads_RemActive: %p %i (%s) removed, giFreeTickets = %i",
- ret, ret->TID, ret->ThreadName, giFreeTickets);
+ Log("Threads_RemActive: CPU%i %p %i (%s) removed, giFreeTickets = %i",
+ GetCPUNum(), ret, ret->TID, ret->ThreadName, giFreeTickets);
#endif
SHORTREL( &glThreadListLock );
Proc_CallFaultHandler(thread);
}
+/**
+ * \fn void Threads_SegFault(tVAddr Addr)
+ * \brief Called when a Segment Fault occurs
+ */
+void Threads_SegFault(tVAddr Addr)
+{
+ Warning("Thread #%i committed a segfault at address %p", Proc_GetCurThread()->TID, Addr);
+ Threads_Fault( 1 );
+ //Threads_Exit( 0, -1 );
+}
+
// --- Process Structure Access Functions ---
tPID Threads_GetPID(void)
{
case THREAD_STAT_MUTEXSLEEP:
Log(" Mutex Pointer: %p", thread->WaitPointer);
break;
+ case THREAD_STAT_SEMAPHORESLEEP:
+ Log(" Semaphore Pointer: %p", thread->WaitPointer);
+ Log(" Semaphore Name: %s:%s",
+ ((tSemaphore*)thread->WaitPointer)->ModName,
+ ((tSemaphore*)thread->WaitPointer)->Name
+ );
+ break;
case THREAD_STAT_ZOMBIE:
Log(" Return Status: %i", thread->RetStatus);
break;
// Clear Delete Queue
// - I should probably put this in a worker thread to avoid calling free() in the scheduler
+ // DEFINITELY - free() can deadlock in this case
while(gDeleteThreads)
{
thread = gDeleteThreads->Next;
- if( IS_LOCKED(&gDeleteThreads->IsLocked) ) { // Only free if structure is unused
+ // Only free if structure is unused
+ if( !IS_LOCKED(&gDeleteThreads->IsLocked) )
+ {
// Set to dead
gDeleteThreads->Status = THREAD_STAT_BURIED;
// Free name
return thread;
}
-/**
- * \fn void Threads_SegFault(tVAddr Addr)
- * \brief Called when a Segment Fault occurs
- */
-void Threads_SegFault(tVAddr Addr)
-{
- Warning("Thread #%i committed a segfault at address %p", Proc_GetCurThread()->TID, Addr);
- Threads_Fault( 1 );
- //Threads_Exit( 0, -1 );
-}
-
/**
* \brief Acquire a heavy mutex
* \param Mutex Mutex to acquire
* the oldest thread (top thread) on the queue is given the lock and
* restarted.
*/
-void Mutex_Acquire(tMutex *Mutex)
+int Mutex_Acquire(tMutex *Mutex)
{
tThread *us = Proc_GetCurThread();
Mutex->Owner = us;
SHORTREL( &Mutex->Protector );
}
+
+ #if 0
+ extern tMutex glPhysAlloc;
+ if( Mutex != &glPhysAlloc )
+ LogF("Mutex %p taken by %i %p\n", Mutex, us->TID, __builtin_return_address(0));
+ #endif
+
+ return 0;
}
/**
* \brief Release a held mutex
* \param Mutex Mutex to release
+ * \note Releasing a non-held mutex has no effect
*/
void Mutex_Release(tMutex *Mutex)
{
Mutex->Owner = NULL;
}
SHORTREL( &Mutex->Protector );
+
+ #if 0
+ extern tMutex glPhysAlloc;
+ if( Mutex != &glPhysAlloc )
+ LogF("Mutex %p released by %i %p\n", Mutex, Threads_GetTID(), __builtin_return_address(0));
+ #endif
}
/**
return Mutex->Owner != NULL;
}
+//
+// Initialise a semaphore
+//
+void Semaphore_Init(tSemaphore *Sem, int Value, int MaxValue, const char *Module, const char *Name)
+{
+ memset(Sem, 0, sizeof(tSemaphore));
+ Sem->Value = Value;
+ Sem->ModName = Module;
+ Sem->Name = Name;
+ Sem->MaxValue = MaxValue;
+}
+//
+// Wait for items to be avaliable
+//
+int Semaphore_Wait(tSemaphore *Sem, int MaxToTake)
+{
+ tThread *us;
+ int taken;
+ if( MaxToTake < 0 ) {
+ Log_Warning("Threads", "Semaphore_Wait: User bug - MaxToTake(%i) < 0, Sem=%p(%s)",
+ MaxToTake, Sem, Sem->Name);
+ }
+
+ SHORTLOCK( &Sem->Protector );
+
+ // Check if there's already items avaliable
+ if( Sem->Value > 0 ) {
+ // Take what we need
+ if( MaxToTake && Sem->Value > MaxToTake )
+ taken = MaxToTake;
+ else
+ taken = Sem->Value;
+ Sem->Value -= taken;
+ SHORTREL( &Sem->Protector );
+ }
+ else
+ {
+ SHORTLOCK( &glThreadListLock );
+
+ // - Remove from active list
+ us = Threads_RemActive();
+ us->Next = NULL;
+ // - Mark as sleeping
+ us->Status = THREAD_STAT_SEMAPHORESLEEP;
+ us->WaitPointer = Sem;
+ us->RetStatus = MaxToTake; // Use RetStatus as a temp variable
+
+ // - Add to waiting
+ if(Sem->LastWaiting) {
+ Sem->LastWaiting->Next = us;
+ Sem->LastWaiting = us;
+ }
+ else {
+ Sem->Waiting = us;
+ Sem->LastWaiting = us;
+ }
+
+ SHORTREL( &glThreadListLock );
+ SHORTREL( &Sem->Protector );
+ while(us->Status == THREAD_STAT_SEMAPHORESLEEP) Threads_Yield();
+ // We're only woken when there's something avaliable
+ us->WaitPointer = NULL;
+
+ taken = us->RetStatus;
+
+ // Get the lock again
+ SHORTLOCK( &Sem->Protector );
+ }
+
+ // While there is space, and there are thread waiting
+ // wake the first thread and give it what it wants (or what's left)
+ while( (Sem->MaxValue == 0 || Sem->Value < Sem->MaxValue) && Sem->Signaling )
+ {
+ int given;
+ tThread *toWake = Sem->Signaling;
+
+ Sem->Signaling = Sem->Signaling->Next;
+ // Reset ->LastWaiting to NULL if we have just removed the last waiting thread
+ if( Sem->Signaling == NULL )
+ Sem->LastSignaling = NULL;
+
+ // Figure out how much to give
+ if( toWake->RetStatus && Sem->Value + toWake->RetStatus < Sem->MaxValue )
+ given = toWake->RetStatus;
+ else
+ given = Sem->MaxValue - Sem->Value;
+ Sem->Value -= given;
+
+ // Save the number we gave to the thread's status
+ toWake->RetStatus = given;
+
+ // Wake the sleeper
+ SHORTLOCK( &glThreadListLock );
+ if( toWake->Status != THREAD_STAT_ACTIVE )
+ Threads_AddActive(toWake);
+ SHORTREL( &glThreadListLock );
+ }
+ SHORTREL( &Sem->Protector );
+
+ return taken;
+}
+
+//
+// Add items to a semaphore
+//
+int Semaphore_Signal(tSemaphore *Sem, int AmmountToAdd)
+{
+ int given;
+ int added;
+
+ if( AmmountToAdd < 0 ) {
+ Log_Warning("Threads", "Semaphore_Signal: User bug - AmmountToAdd(%i) < 0, Sem=%p(%s)",
+ AmmountToAdd, Sem, Sem->Name);
+ }
+ SHORTLOCK( &Sem->Protector );
+
+ // Check if we have to block
+ if( Sem->MaxValue && Sem->Value == Sem->MaxValue )
+ {
+ tThread *us;
+ SHORTLOCK( &glThreadListLock );
+
+ // - Remove from active list
+ us = Threads_RemActive();
+ us->Next = NULL;
+ // - Mark as sleeping
+ us->Status = THREAD_STAT_SEMAPHORESLEEP;
+ us->WaitPointer = Sem;
+ us->RetStatus = AmmountToAdd; // Use RetStatus as a temp variable
+
+ // - Add to waiting
+ if(Sem->LastSignaling) {
+ Sem->LastSignaling->Next = us;
+ Sem->LastSignaling = us;
+ }
+ else {
+ Sem->Signaling = us;
+ Sem->LastSignaling = us;
+ }
+
+ SHORTREL( &glThreadListLock );
+ SHORTREL( &Sem->Protector );
+ while(us->Status == THREAD_STAT_SEMAPHORESLEEP) Threads_Yield();
+ // We're only woken when there's something avaliable
+ us->WaitPointer = NULL;
+
+ added = us->RetStatus;
+
+ // Get the lock again
+ SHORTLOCK( &Sem->Protector );
+ }
+ // Non blocking
+ else
+ {
+ // Figure out how much we need to take off
+ if( Sem->MaxValue && Sem->Value + AmmountToAdd > Sem->MaxValue)
+ added = Sem->MaxValue - Sem->Value;
+ else
+ added = AmmountToAdd;
+ Sem->Value += added;
+ }
+
+ // While there are items avaliable, and there are thread waiting
+ // wake the first thread and give it what it wants (or what's left)
+ while( Sem->Value && Sem->Waiting )
+ {
+ tThread *toWake = Sem->Waiting;
+
+ Sem->Waiting = Sem->Waiting->Next;
+ // Reset ->LastWaiting to NULL if we have just removed the last waiting thread
+ if( Sem->Waiting == NULL )
+ Sem->LastWaiting = NULL;
+
+ // Figure out how much to give
+ if( toWake->RetStatus && Sem->Value > toWake->RetStatus )
+ given = toWake->RetStatus;
+ else
+ given = Sem->Value;
+ Sem->Value -= given;
+
+ // Save the number we gave to the thread's status
+ toWake->RetStatus = given;
+
+ // Wake the sleeper
+ SHORTLOCK( &glThreadListLock );
+ if( toWake->Status != THREAD_STAT_ACTIVE )
+ Threads_AddActive(toWake);
+ SHORTREL( &glThreadListLock );
+ }
+ SHORTREL( &Sem->Protector );
+
+ return added;
+}
+
+//
+// Get the current value of a semaphore
+//
+int Semaphore_GetValue(tSemaphore *Sem)
+{
+ return Sem->Value;
+}
+
// === EXPORTS ===
EXPORT(Threads_GetUID);
EXPORT(Threads_GetGID);
EXPORT(Mutex_Acquire);
EXPORT(Mutex_Release);
EXPORT(Mutex_IsLocked);
+EXPORT(Semaphore_Init);
+EXPORT(Semaphore_Wait);
+EXPORT(Semaphore_Signal);