X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Fthreads.c;h=b9d59f3f00c14644f2678b4bcede04a43c614837;hb=da67fd4fd32d16dcd6b4cb0b63497a9925a2ef35;hp=90eb740e49829d63bbc54ce81205856c674f92ba;hpb=a4ce2e60f783c9e71447edc03f20f937b8abf35a;p=tpg%2Facess2.git diff --git a/Kernel/threads.c b/Kernel/threads.c index 90eb740e..b9d59f3f 100644 --- a/Kernel/threads.c +++ b/Kernel/threads.c @@ -7,156 +7,168 @@ #include #include +#define DEBUG_TRACE_TICKETS 0 // Trace ticket counts +#define DEBUG_TRACE_STATE 0 // Trace state changes (sleep/wake) + // === CONSTANTS === #define DEFAULT_QUANTUM 10 #define DEFAULT_TICKETS 5 #define MAX_TICKETS 10 const enum eConfigTypes cCONFIG_TYPES[] = { - CFGT_HEAPSTR, // CFG_VFS_CWD - CFGT_INT, // CFG_VFS_MAXFILES + CFGT_HEAPSTR, // e.g. CFG_VFS_CWD + CFGT_INT, // e.g. CFG_VFS_MAXFILES CFGT_NULL }; // === IMPORTS === -extern void ArchThreads_Init(); -extern void Proc_Start(); -extern tThread *Proc_GetCurThread(); +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); // === PROTOTYPES === -void Threads_Init(); -void Threads_SetName(char *NewName); +void Threads_Init(void); + int Threads_SetName(char *NewName); char *Threads_GetName(int ID); -void Threads_SetTickets(int Num); +void Threads_SetTickets(tThread *Thread, int Num); tThread *Threads_CloneTCB(Uint *Err, Uint Flags); int Threads_WaitTID(int TID, int *status); tThread *Threads_GetThread(Uint TID); void Threads_AddToDelete(tThread *Thread); -tThread *Threads_int_GetPrev(tThread **List, tThread *Thread); +tThread *Threads_int_DelFromQueue(tThread **List, tThread *Thread); void Threads_Exit(int TID, int Status); void Threads_Kill(tThread *Thread, int Status); -void Threads_Yield(); -void Threads_Sleep(); -void Threads_Wake(tThread *Thread); +void Threads_Yield(void); +void Threads_Sleep(void); + int Threads_Wake(tThread *Thread); void Threads_AddActive(tThread *Thread); - int Threads_GetPID(); - int Threads_GetTID(); - int Threads_GetUID(); - int Threads_GetGID(); -void Threads_Dump(); +tThread *Threads_RemActive(void); + 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_SetGID(Uint *Errno, tUID ID); +void Threads_Dump(void); +void Threads_DumpActive(void); +void Mutex_Acquire(tMutex *Mutex); +void Mutex_Release(tMutex *Mutex); + int Mutex_IsLocked(tMutex *Mutex); // === GLOBALS === // -- Core Thread -- +// Only used for the core kernel tThread gThreadZero = { - NULL, 0, // Next, Lock - THREAD_STAT_ACTIVE, // Status - 0, // Exit Status - 0, 0, // TID, TGID - 0, 0, // UID, GID - 0, // Parent Thread ID - "ThreadZero", // Name - - 0, // Kernel Stack - {0}, // Saved State - {0}, // VM State - - 0, {0}, {0}, // Signal State - - NULL, NULL, // Messages, Last Message - DEFAULT_QUANTUM, DEFAULT_QUANTUM, // Quantum, Remaining - DEFAULT_TICKETS, - {0} // Default config to zero + Status: THREAD_STAT_ACTIVE, // Status + ThreadName: "ThreadZero", // Name + Quantum: DEFAULT_QUANTUM, // Default Quantum + Remaining: DEFAULT_QUANTUM, // Current Quantum + NumTickets: DEFAULT_TICKETS // Number of tickets }; // -- Processes -- // --- Locks --- -volatile int giThreadListLock = 0; ///\note NEVER use a heap function while locked +tShortSpinlock glThreadListLock; ///\note NEVER use a heap function while locked // --- Current State --- -volatile int giNumActiveThreads = 0; -volatile int giTotalTickets = 0; -volatile Uint giNextTID = 1; +volatile int giNumActiveThreads = 0; // Number of threads on the active queue +volatile int giFreeTickets = 0; // Number of tickets held by non-scheduled threads +volatile Uint giNextTID = 1; // Next TID to allocate // --- Thread Lists --- +tThread *gAllThreads = NULL; // All allocated threads tThread *gActiveThreads = NULL; // Currently Running Threads tThread *gSleepingThreads = NULL; // Sleeping Threads tThread *gDeleteThreads = NULL; // Threads to delete - int giNumCPUs = 1; + int giNumCPUs = 1; // Number of CPUs +BOOL gaThreads_NoTaskSwitch[MAX_CPUS]; // Disables task switches for each core (Pseudo-IF) // === CODE === /** - * \fn void Threads_Init() + * \fn void Threads_Init(void) * \brief Initialse the thread list */ -void Threads_Init() +void Threads_Init(void) { ArchThreads_Init(); // Create Initial Task gActiveThreads = &gThreadZero; - giTotalTickets = gThreadZero.NumTickets; + gAllThreads = &gThreadZero; + //giFreeTickets = gThreadZero.NumTickets; // Not needed, as ThreadZero is scheduled giNumActiveThreads = 1; - - #if 1 - // Create Idle Task - if(Proc_Clone(0, 0) == 0) - { - tThread *cur = Proc_GetCurThread(); - cur->ThreadName = "Idle Thread"; - Threads_SetTickets(0); // Never called randomly - cur->Quantum = 1; // 1 slice quantum - HALT(); - for(;;) { - HALT(); // Just yeilds - } - } - #endif - + Proc_Start(); } /** * \fn void Threads_SetName(char *NewName) * \brief Sets the current thread's name + * \param NewName New name for the thread + * \return Boolean Failure */ -void Threads_SetName(char *NewName) +int Threads_SetName(char *NewName) { tThread *cur = Proc_GetCurThread(); - if( IsHeap(cur->ThreadName) ) - free( cur->ThreadName ); - cur->ThreadName = malloc(strlen(NewName)+1); - strcpy(cur->ThreadName, NewName); + char *oldname = cur->ThreadName; + + // NOTE: There is a possibility of non-thread safety here + // A thread could read the current name pointer before it is zeroed + + cur->ThreadName = NULL; + + if( IsHeap(oldname) ) free( oldname ); + + cur->ThreadName = strdup(NewName); + return 0; } /** * \fn char *Threads_GetName(int ID) * \brief Gets a thread's name + * \param ID Thread ID (-1 indicates current thread) + * \return Pointer to name + * \retval NULL Failure */ -char *Threads_GetName(int ID) +char *Threads_GetName(tTID ID) { if(ID == -1) { return Proc_GetCurThread()->ThreadName; } - return NULL; + return Threads_GetThread(ID)->ThreadName; } /** - * \fn void Threads_SetTickets(int Num) + * \fn void Threads_SetTickets(tThread *Thread, int Num) * \brief Sets the 'priority' of a task + * \param Thread Thread to update ticket count (NULL means current thread) + * \param Num New ticket count (must be >= 0, clipped to \a MAX_TICKETS) */ -void Threads_SetTickets(int Num) +void Threads_SetTickets(tThread *Thread, int Num) { - tThread *cur = Proc_GetCurThread(); + // Get current thread + if(Thread == NULL) Thread = Proc_GetCurThread(); + // Bounds checking if(Num < 0) return; if(Num > MAX_TICKETS) Num = MAX_TICKETS; - LOCK( &giThreadListLock ); - giTotalTickets -= cur->NumTickets; - cur->NumTickets = Num; - giTotalTickets += Num; - //LOG("giTotalTickets = %i", giTotalTickets); - RELEASE( &giThreadListLock ); + // If this isn't the current thread, we need to lock + if( Thread != Proc_GetCurThread() ) { + SHORTLOCK( &glThreadListLock ); + giFreeTickets -= Thread->NumTickets - Num; + Thread->NumTickets = Num; + #if DEBUG_TRACE_TICKETS + Log("Threads_SetTickets: new giFreeTickets = %i", giFreeTickets); + #endif + SHORTREL( &glThreadListLock ); + } + else + Thread->NumTickets = Num; } /** * \fn tThread *Threads_CloneTCB(Uint *Err, Uint Flags) + * \brief Clone the TCB of the current thread + * \param Err Error pointer + * \param Flags Flags for something... (What is this for?) */ tThread *Threads_CloneTCB(Uint *Err, Uint Flags) { @@ -164,24 +176,26 @@ tThread *Threads_CloneTCB(Uint *Err, Uint Flags) int i; cur = Proc_GetCurThread(); + // Allocate and duplicate new = malloc(sizeof(tThread)); if(new == NULL) { *Err = -ENOMEM; return NULL; } + memcpy(new, cur, sizeof(tThread)); + new->CurCPU = -1; new->Next = NULL; - new->IsLocked = 0; - new->Status = THREAD_STAT_ACTIVE; + memset( &new->IsLocked, 0, sizeof(new->IsLocked)); + new->Status = THREAD_STAT_PREINIT; new->RetStatus = 0; // Get Thread ID new->TID = giNextTID++; - new->PTID = cur->TID; + new->Parent = cur; // Clone Name - new->ThreadName = malloc(strlen(cur->ThreadName)+1); - strcpy(new->ThreadName, cur->ThreadName); + new->ThreadName = strdup(cur->ThreadName); // Set Thread Group ID (PID) if(Flags & CLONE_VM) @@ -198,12 +212,8 @@ tThread *Threads_CloneTCB(Uint *Err, Uint Flags) new->NumTickets = cur->NumTickets; // Set Signal Handlers - new->CurSignal = 0; - if(Flags & CLONE_VM) - memset(new->SignalHandlers, 0, sizeof(new->SignalHandlers)); - else - memcpy(new->SignalHandlers, cur->SignalHandlers, sizeof(new->SignalHandlers)); - memset(&new->SignalState, 0, sizeof(tTaskState)); + new->CurFaultNum = 0; + new->FaultHandler = cur->FaultHandler; for( i = 0; i < NUM_CFG_ENTRIES; i ++ ) { @@ -221,42 +231,54 @@ tThread *Threads_CloneTCB(Uint *Err, Uint Flags) } } + // Maintain a global list of threads + SHORTLOCK( &glThreadListLock ); + new->GlobalPrev = NULL; // Protect against bugs + new->GlobalNext = gAllThreads; + gAllThreads = new; + SHORTREL( &glThreadListLock ); + return new; } /** - * \fn Uint *Threads_GetCfgPtr(int Id) + * \brief Get a configuration pointer from the Per-Thread data area + * \param ID Config slot ID + * \return Pointer at ID */ -Uint *Threads_GetCfgPtr(int Id) +Uint *Threads_GetCfgPtr(int ID) { - if(Id < 0 || Id >= NUM_CFG_ENTRIES) { - Warning("Threads_GetCfgPtr: Index %i is out of bounds", Id); + if(ID < 0 || ID >= NUM_CFG_ENTRIES) { + Warning("Threads_GetCfgPtr: Index %i is out of bounds", ID); return NULL; } - return &Proc_GetCurThread()->Config[Id]; + return &Proc_GetCurThread()->Config[ID]; } /** - * \fn void Threads_WaitTID(int TID, int *status) * \brief Wait for a task to change state + * \param TID Thread ID to wait on (-1: Any child thread, 0: Any Child/Sibling, <-1: -PID) + * \param Status Thread return status + * \return TID of child that changed state */ -int Threads_WaitTID(int TID, int *status) +tTID Threads_WaitTID(int TID, int *Status) { // Any Child if(TID == -1) { - + Log_Error("Threads", "TODO: Threads_WaitTID(TID=-1) - Any Child"); return -1; } // Any peer/child thread if(TID == 0) { - + Log_Error("Threads", "TODO: Threads_WaitTID(TID=0) - Any Child/Sibling"); return -1; } // TGID = abs(TID) if(TID < -1) { + Log_Error("Threads", "TODO: Threads_WaitTID(TID<0) - TGID"); return -1; } @@ -264,23 +286,34 @@ int Threads_WaitTID(int TID, int *status) if(TID > 0) { tThread *t = Threads_GetThread(TID); int initStatus = t->Status; - int ret; + tTID ret; - if(initStatus != THREAD_STAT_ZOMBIE) - while(t->Status == initStatus) { - Threads_Yield(); + // Wait for the thread to die! + if(initStatus != THREAD_STAT_ZOMBIE) { + // TODO: Handle child also being suspended if wanted + while(t->Status != THREAD_STAT_ZOMBIE) { + Threads_Sleep(); + Log_Debug("Threads", "%i waiting for %i, t->Status = %i", + Threads_GetTID(), t->TID, t->Status); } + } - ret = t->RetStatus; + // Set return status + Log_Debug("Threads", "%i waiting for %i, t->Status = %i", + Threads_GetTID(), t->TID, t->Status); + ret = t->TID; switch(t->Status) { case THREAD_STAT_ZOMBIE: + // Kill the thread t->Status = THREAD_STAT_DEAD; - if(status) *status = 0; + // TODO: Child return value? + if(Status) *Status = t->RetStatus; + // add to delete queue Threads_AddToDelete( t ); break; default: - if(status) *status = -1; + if(Status) *Status = -1; break; } return ret; @@ -290,41 +323,36 @@ int Threads_WaitTID(int TID, int *status) } /** - * \fn tThread *Threads_GetThread(Uint TID) * \brief Gets a thread given its TID + * \param TID Thread ID + * \return Thread pointer */ tThread *Threads_GetThread(Uint TID) { tThread *thread; - // Search Active List - for(thread = gActiveThreads; + // Search global list + for(thread = gAllThreads; thread; - thread = thread->Next) - { - if(thread->TID == TID) - return thread; - } - - // Search Sleeping List - for(thread = gSleepingThreads; - thread; - thread = thread->Next) + thread = thread->GlobalNext) { if(thread->TID == TID) return thread; } + + Log("Unable to find TID %i on main list\n", TID); return NULL; } /** - * \fn void Threads_AddToDelete(tThread *Thread) * \brief Adds a thread to the delete queue + * \param Thread Thread to delete */ void Threads_AddToDelete(tThread *Thread) { // Add to delete queue + // TODO: Is locking needed? if(gDeleteThreads) { Thread->Next = gDeleteThreads; gDeleteThreads = Thread; @@ -335,31 +363,42 @@ void Threads_AddToDelete(tThread *Thread) } /** - * \fn tThread *Threads_int_GetPrev(tThread **List, tThread *Thread) - * \brief Gets the previous entry in a thead linked list + * \brief Deletes an entry from a list + * \param List Pointer to the list head + * \param Thread Thread to find + * \return \a Thread */ -tThread *Threads_int_GetPrev(tThread **List, tThread *Thread) +tThread *Threads_int_DelFromQueue(tThread **List, tThread *Thread) { - tThread *ret; - // First Entry - if(*List == Thread) { - return (tThread*)List; - } else { - for(ret = *List; - ret->Next && ret->Next != Thread; - ret = ret->Next - ); - // Error if the thread is not on the list - if(!ret->Next || ret->Next != Thread) { - return NULL; - } + tThread *ret, *prev = NULL; + + for(ret = *List; + ret && ret != Thread; + prev = ret, ret = ret->Next + ); + + // Is the thread on the list + if(!ret) { + //LogF("%p(%s) is not on list %p\n", Thread, Thread->ThreadName, List); + return NULL; } - return ret; + + if( !prev ) { + *List = Thread->Next; + //LogF("%p(%s) removed from head of %p\n", Thread, Thread->ThreadName, List); + } + else { + prev->Next = Thread->Next; + //LogF("%p(%s) removed from %p (prev=%p)\n", Thread, Thread->ThreadName, List, prev); + } + + return Thread; } /** - * \fn void Threads_Exit(int TID, int Status) - * \brief Exit the current process + * \brief Exit the current process (or another?) + * \param TID Thread ID to kill + * \param Status Exit status */ void Threads_Exit(int TID, int Status) { @@ -367,7 +406,9 @@ void Threads_Exit(int TID, int Status) Threads_Kill( Proc_GetCurThread(), (Uint)Status & 0xFF ); else Threads_Kill( Threads_GetThread(TID), (Uint)Status & 0xFF ); - for(;;) HALT(); // Just in case + + // Halt forever, just in case + for(;;) HALT(); } /** @@ -378,13 +419,13 @@ void Threads_Exit(int TID, int Status) */ void Threads_Kill(tThread *Thread, int Status) { - tThread *prev; tMsg *msg; - // Kill all children + // TODO: Kill all children #if 0 { tThread *child; + // TODO: I should keep a .Parent pointer, and a .Children list for(child = gActiveThreads; child; child = child->Next) @@ -395,20 +436,10 @@ void Threads_Kill(tThread *Thread, int Status) } #endif - ///\note Double lock is needed due to overlap of locks + ///\note Double lock is needed due to overlap of lock areas // Lock thread (stop us recieving messages) - LOCK( &Thread->IsLocked ); - - // Lock thread list - LOCK( &giThreadListLock ); - - // Get previous thread on list - prev = Threads_int_GetPrev( &gActiveThreads, Thread ); - if(!prev) { - Warning("Proc_Exit - Current thread is not on the active queue"); - return; - } + SHORTLOCK( &Thread->IsLocked ); // Clear Message Queue while( Thread->Messages ) @@ -418,282 +449,526 @@ void Threads_Kill(tThread *Thread, int Status) Thread->Messages = msg; } + // Lock thread list + SHORTLOCK( &glThreadListLock ); + + // Delete from active list + if( !Threads_int_DelFromQueue( &gActiveThreads, Thread ) ) + { + Warning("Proc_Exit - Current thread is not on the active queue"); + 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 - prev->Next = Thread->Next; // Remove from active + // Update bookkeeping giNumActiveThreads --; - giTotalTickets -= Thread->NumTickets; + if( Thread != Proc_GetCurThread() ) + giFreeTickets -= Thread->NumTickets; - // Mark thread as a zombie + // Save exit status Thread->RetStatus = Status; - // Don't Zombie if we are being killed as part of a tree + // Don't Zombie if we are being killed because our parent is if(Status == -1) { Thread->Status = THREAD_STAT_DEAD; Threads_AddToDelete( Thread ); } else { Thread->Status = THREAD_STAT_ZOMBIE; + // Wake parent + Threads_Wake( Thread->Parent ); } - // Release spinlocks - RELEASE( &Thread->IsLocked ); // Released first so that it IS released - RELEASE( &giThreadListLock ); + Log("Thread %i went *hurk* (%i)", Thread->TID, Thread->Status); - //Log("Thread %i went *hurk*", Thread->TID); + // Release spinlocks + SHORTREL( &glThreadListLock ); + SHORTREL( &Thread->IsLocked ); // TODO: We may not actually be released... - if(Status != -1) HALT(); + // And, reschedule + if(Status != -1) { + for( ;; ) + HALT(); + } } /** - * \fn void Threads_Yield() - * \brief Yield remainder of timeslice + * \brief Yield remainder of the current thread's timeslice */ -void Threads_Yield() +void Threads_Yield(void) { - Proc_GetCurThread()->Remaining = 0; - HALT(); + tThread *thread = Proc_GetCurThread(); + thread->Remaining = 0; + //while(thread->Remaining == 0) + HALT(); } /** - * \fn void Threads_Sleep() + * \fn void Threads_Sleep(void) * \brief Take the current process off the run queue */ -void Threads_Sleep() +void Threads_Sleep(void) { tThread *cur = Proc_GetCurThread(); - tThread *thread; - - Log("Proc_Sleep: %i going to sleep", cur->TID); // Acquire Spinlock - LOCK( &giThreadListLock ); - - // Get thread before current thread - thread = Threads_int_GetPrev( &gActiveThreads, cur ); - if(!thread) { - Warning("Threads_Sleep - Current thread is not on the active queue"); - Threads_Dump(); - return; - } + SHORTLOCK( &glThreadListLock ); // Don't sleep if there is a message waiting if( cur->Messages ) { - RELEASE( &giThreadListLock ); + SHORTREL( &glThreadListLock ); return; } - // Unset remaining timeslices (force a task switch on timer fire) - cur->Remaining = 0; - - // Remove from active list - thread->Next = cur->Next; + // Remove us from running queue + Threads_RemActive(); + // Mark thread as sleeping + cur->Status = THREAD_STAT_SLEEPING; // Add to Sleeping List (at the top) cur->Next = gSleepingThreads; gSleepingThreads = cur; - // Reduce the active count & ticket count - giNumActiveThreads --; - giTotalTickets -= cur->NumTickets; - // Mark thread as sleeping - cur->Status = THREAD_STAT_SLEEPING; + #if DEBUG_TRACE_STATE + Log("Threads_Sleep: %p (%i %s) sleeping", cur, cur->TID, cur->ThreadName); + #endif // Release Spinlock - RELEASE( &giThreadListLock ); + SHORTREL( &glThreadListLock ); while(cur->Status != THREAD_STAT_ACTIVE) HALT(); } /** - * \fn void Threads_Wake( tThread *Thread ) + * \fn int Threads_Wake( tThread *Thread ) * \brief Wakes a sleeping/waiting thread up + * \param Thread Thread to wake + * \return Boolean Failure (Returns ERRNO) + * \warning This should ONLY be called with task switches disabled */ -void Threads_Wake(tThread *Thread) +int Threads_Wake(tThread *Thread) { - tThread *prev; + if(!Thread) + return -EINVAL; + switch(Thread->Status) { - case THREAD_STAT_ACTIVE: break; + case THREAD_STAT_ACTIVE: + Log("Thread_Wake: Waking awake thread (%i)", Thread->TID); + return -EALREADY; + case THREAD_STAT_SLEEPING: - LOCK( &giThreadListLock ); - prev = Threads_int_GetPrev(&gSleepingThreads, Thread); - prev->Next = Thread->Next; // Remove from sleeping queue - Thread->Next = gActiveThreads; // Add to active queue - gActiveThreads = Thread; - Thread->Status = THREAD_STAT_ACTIVE; - RELEASE( &giThreadListLock ); - break; + SHORTLOCK( &glThreadListLock ); + // Remove from sleeping queue + Threads_int_DelFromQueue(&gSleepingThreads, Thread); + + Threads_AddActive( Thread ); + + #if DEBUG_TRACE_STATE + Log("Threads_Sleep: %p (%i %s) woken", Thread, Thread->TID, Thread->ThreadName); + #endif + SHORTREL( &glThreadListLock ); + return -EOK; + case THREAD_STAT_WAITING: Warning("Thread_Wake - Waiting threads are not currently supported"); - break; + return -ENOTIMPL; + case THREAD_STAT_DEAD: Warning("Thread_Wake - Attempt to wake dead thread (%i)", Thread->TID); - break; + return -ENOTIMPL; + default: Warning("Thread_Wake - Unknown process status (%i)\n", Thread->Status); - break; + return -EINTERNAL; } } /** - * \fn void Threads_AddActive(tThread *Thread) + * \brief Wake a thread given the TID + * \param TID Thread ID to wake + * \return Boolean Faulure (errno) + */ +int Threads_WakeTID(tTID TID) +{ + tThread *thread = Threads_GetThread(TID); + int ret; + if(!thread) + return -ENOENT; + ret = Threads_Wake( thread ); + //Log_Debug("Threads", "TID %i woke %i (%p)", Threads_GetTID(), TID, thread); + return ret; +} + +/** * \brief Adds a thread to the active queue */ void Threads_AddActive(tThread *Thread) { - LOCK( &giThreadListLock ); + SHORTLOCK( &glThreadListLock ); + + #if 1 + { + tThread *t; + for( t = gActiveThreads; t; t = t->Next ) + { + if( t == Thread ) { + Panic("Threads_AddActive: Attempting a double add of TID %i (0x%x)", + Thread->TID, __builtin_return_address(0)); + } + + if(t->Status != THREAD_STAT_ACTIVE) { + Panic("Threads_AddActive: TID %i status != THREAD_STAT_ACTIVE", + Thread->TID); + } + } + } + #endif + + // Set state + Thread->Status = THREAD_STAT_ACTIVE; + Thread->CurCPU = -1; + // Add to active list Thread->Next = gActiveThreads; gActiveThreads = Thread; + + // Update bookkeeping giNumActiveThreads ++; - giTotalTickets += Thread->NumTickets; - //Log("Threads_AddActive: giNumActiveThreads = %i, giTotalTickets = %i", - // giNumActiveThreads, giTotalTickets); - RELEASE( &giThreadListLock ); + giFreeTickets += Thread->NumTickets; + + #if DEBUG_TRACE_TICKETS + Log("Threads_AddActive: %p %i (%s) added, new giFreeTickets = %i", + Thread, Thread->TID, Thread->ThreadName, giFreeTickets); + #endif + SHORTREL( &glThreadListLock ); } -#if 0 /** - * \fn void Threads_SetSignalHandler(int Num, void *Handler) - * \brief Sets the signal handler for a signal + * \brief Removes the current thread from the active queue + * \warning This should ONLY be called with task switches disabled + * \return Current thread pointer */ -void Threads_SetSignalHandler(int Num, void *Handler) +tThread *Threads_RemActive(void) { - if(Num < 0 || Num >= NSIG) return; + tThread *ret = Proc_GetCurThread(); + + SHORTLOCK( &glThreadListLock ); - gCurrentThread->SignalHandlers[Num] = Handler; + // Delete from active queue + if( !Threads_int_DelFromQueue(&gActiveThreads, ret) ) { + SHORTREL( &glThreadListLock ); + return NULL; + } + + ret->Remaining = 0; + ret->CurCPU = -1; + + giNumActiveThreads --; + // no need to decrement tickets, scheduler did it for us + + #if DEBUG_TRACE_TICKETS + Log("Threads_RemActive: %p %i (%s) removed, giFreeTickets = %i", + ret, ret->TID, ret->ThreadName, giFreeTickets); + #endif + + SHORTREL( &glThreadListLock ); + + return ret; +} + +/** + * \fn void Threads_SetFaultHandler(Uint Handler) + * \brief Sets the signal handler for a signal + */ +void Threads_SetFaultHandler(Uint Handler) +{ + //Log_Debug("Threads", "Threads_SetFaultHandler: Handler = %p", Handler); + Proc_GetCurThread()->FaultHandler = Handler; } /** - * \fn void Threads_SendSignal(int TID, int Num) - * \brief Send a signal to a thread + * \fn void Threads_Fault(int Num) + * \brief Calls a fault handler */ -void Threads_SendSignal(int TID, int Num) +void Threads_Fault(int Num) { - tThread *thread = Proc_GetThread(TID); - void *handler; + tThread *thread = Proc_GetCurThread(); + + Log_Log("Threads", "Threads_Fault: thread = %p", thread); if(!thread) return ; - handler = thread->SignalHandlers[Num]; + Log_Log("Threads", "Threads_Fault: thread->FaultHandler = %p", thread->FaultHandler); - // Panic? - if(handler == SIG_ERR) { - Proc_Kill(TID); + switch(thread->FaultHandler) + { + case 0: // Panic? + Threads_Kill(thread, -1); + HALT(); return ; - } - // Dump Core? - if(handler == -2) { - Proc_Kill(TID); + case 1: // Dump Core? + Threads_Kill(thread, -1); + HALT(); 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(); - } + // Double Fault? Oh, F**k + if(thread->CurFaultNum != 0) { + Threads_Kill(thread, -1); // For now, just kill + HALT(); } - //TODO: + thread->CurFaultNum = Num; + + Proc_CallFaultHandler(thread); } -#endif // --- Process Structure Access Functions --- -int Threads_GetPID() +tPID Threads_GetPID(void) { return Proc_GetCurThread()->TGID; } -int Threads_GetTID() +tTID Threads_GetTID(void) { return Proc_GetCurThread()->TID; } -int Threads_GetUID() +tUID Threads_GetUID(void) { return Proc_GetCurThread()->UID; } -int Threads_GetGID() +tGID Threads_GetGID(void) { return Proc_GetCurThread()->GID; } +int Threads_SetUID(Uint *Errno, tUID ID) +{ + tThread *t = Proc_GetCurThread(); + if( t->UID != 0 ) { + *Errno = -EACCES; + return -1; + } + Log_Debug("Threads", "TID %i's UID set to %i", t->TID, ID); + t->UID = ID; + return 0; +} + +int Threads_SetGID(Uint *Errno, tGID ID) +{ + tThread *t = Proc_GetCurThread(); + if( t->UID != 0 ) { + *Errno = -EACCES; + return -1; + } + Log_Debug("Threads", "TID %i's GID set to %i", t->TID, ID); + t->GID = ID; + return 0; +} + /** - * \fn void Threads_Dump() - * \brief Dums a list of currently running threads + * \fn void Threads_Dump(void) + * \brief Dumps a list of currently running threads */ -void Threads_Dump() +void Threads_Dump(void) { tThread *thread; - tThread *cur = Proc_GetCurThread(); - Log("Active Threads:"); + Log("--- Thread Dump ---"); + Log("Active Threads: (%i reported)", giNumActiveThreads); for(thread=gActiveThreads;thread;thread=thread->Next) { - Log("%c%i (%i) - %s", - (thread==cur?'*':' '), - thread->TID, thread->TGID, thread->ThreadName); + Log(" %i (%i) - %s (CPU %i)", + thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU); + 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); + } + + Log("All Threads:"); + for(thread=gAllThreads;thread;thread=thread->GlobalNext) + { + Log(" %i (%i) - %s (CPU %i)", + thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU); + Log(" State %i", thread->Status); Log(" %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum); Log(" KStack 0x%x", thread->KernelStack); } - Log("Sleeping Threads:"); - for(thread=gSleepingThreads;thread;thread=thread->Next) +} +/** + * \fn void Threads_Dump(void) + */ +void Threads_DumpActive(void) +{ + tThread *thread; + + Log("Active Threads:"); + for(thread=gActiveThreads;thread;thread=thread->Next) { - Log("%c%i (%i) - %s", - (thread==cur?'*':' '), - thread->TID, thread->TGID, thread->ThreadName); + Log(" %i (%i) - %s (CPU %i)", + thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU); + 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); } } /** - * \fn tThread *Threads_GetNextToRun(int CPU) * \brief Gets the next thread to run + * \param CPU Current CPU + * \param Last The thread the CPU was running */ -tThread *Threads_GetNextToRun(int CPU) +tThread *Threads_GetNextToRun(int CPU, tThread *Last) { tThread *thread; int ticket; int number; - if(giNumActiveThreads == 0) return NULL; + // If this CPU has the lock, we must let it complete + if( CPU_HAS_LOCK( &glThreadListLock ) ) + return Last; + + // Don't change threads if the current CPU has switches disabled + if( gaThreads_NoTaskSwitch[CPU] ) + return Last; + + + // Lock thread list + 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; + if( IS_LOCKED(&gDeleteThreads->IsLocked) ) { // Only free if structure is unused + // Set to dead + gDeleteThreads->Status = THREAD_STAT_DEAD; + // Free name + if( IsHeap(gDeleteThreads->ThreadName) ) + free(gDeleteThreads->ThreadName); + // Remove from global list + if( gDeleteThreads == gAllThreads ) + gAllThreads = gDeleteThreads->GlobalNext; + else + gDeleteThreads->GlobalPrev->GlobalNext = gDeleteThreads->GlobalNext; + free( gDeleteThreads ); + } + gDeleteThreads = thread; + } + + // No active threads, just take a nap + if(giNumActiveThreads == 0) { + SHORTREL( &glThreadListLock ); + #if DEBUG_TRACE_TICKETS + Log("No active threads"); + #endif + return NULL; + } // Special case: 1 thread if(giNumActiveThreads == 1) { - return gActiveThreads; + if( gActiveThreads->CurCPU == -1 ) + gActiveThreads->CurCPU = CPU; + + SHORTREL( &glThreadListLock ); + + if( gActiveThreads->CurCPU == CPU ) + return gActiveThreads; + + return NULL; // CPU has nothing to do } - //Log(" Threads_GetNextToRun: giNumActiveThreads=%i,giTotalTickets=%i", - // giNumActiveThreads, giTotalTickets); - // Get the ticket number - ticket = number = rand() % giTotalTickets; + // Allow the old thread to be scheduled again + if( Last ) { + if( Last->Status == THREAD_STAT_ACTIVE ) { + giFreeTickets += Last->NumTickets; + #if DEBUG_TRACE_TICKETS + LogF(" CPU %i released %p (%i %s) into the pool (%i tickets in pool)\n", + CPU, Last, Last->TID, Last->ThreadName, giFreeTickets); + #endif + } + #if DEBUG_TRACE_TICKETS + else + LogF(" CPU %i released %p (%i %s)->Status = %i (Released)\n", + CPU, Last, Last->TID, Last->ThreadName, Last->Status); + #endif + Last->CurCPU = -1; + } + + #if DEBUG_TRACE_TICKETS + //Threads_DumpActive(); + #endif + + #if 1 + number = 0; + for(thread = gActiveThreads; thread; thread = thread->Next) { + if(thread->CurCPU >= 0) continue; + if(thread->Status != THREAD_STAT_ACTIVE) + Panic("Bookkeeping fail - %p %i(%s) is on the active queue with a status of %i", + thread, thread->TID, thread->ThreadName, thread->Status); + if(thread->Next == thread) { + Panic("Bookkeeping fail - %p %i(%s) loops back on itself", + thread, thread->TID, thread->ThreadName, thread->Status); + } + number += thread->NumTickets; + } + if(number != giFreeTickets) { + Panic("Bookkeeping fail (giFreeTickets(%i) != number(%i)) - CPU%i", + giFreeTickets, number, CPU); + } + #endif - //Log(" Threads_GetNextToRun: ticket = %i", ticket); + // No free tickets (all tasks delegated to cores) + if( giFreeTickets == 0 ) { + SHORTREL(&glThreadListLock); + return NULL; + } + + // Get the ticket number + ticket = number = rand() % giFreeTickets; // Find the next thread for(thread=gActiveThreads;thread;thread=thread->Next) { + if(thread->CurCPU >= 0) continue; if(thread->NumTickets > number) break; number -= thread->NumTickets; } - // Error Check if(thread == NULL) { number = 0; - for(thread=gActiveThreads;thread;thread=thread->Next) + for(thread=gActiveThreads;thread;thread=thread->Next) { + if(thread->CurCPU >= 0) continue; number += thread->NumTickets; - Panic("Bookeeping Failed - giTotalTicketCount (%i) != true count (%i)", - giTotalTickets, number); + } + Panic("Bookeeping Failed - giFreeTickets(%i) > true count (%i)", + giFreeTickets, number); } + #if DEBUG_TRACE_TICKETS + LogF(" CPU%i giFreeTickets = %i\n", CPU, giFreeTickets); + #endif + + // Make the new thread non-schedulable + giFreeTickets -= thread->NumTickets; + thread->CurCPU = CPU; + + //Threads_Dump(); + #if DEBUG_TRACE_TICKETS + LogF(" CPU%i giFreeTickets = %i, giving %p (%i %s CPU=%i)\n", + CPU, giFreeTickets, thread, thread->TID, thread->ThreadName, thread->CurCPU); + #endif + + SHORTREL( &glThreadListLock ); return thread; } @@ -704,10 +979,101 @@ tThread *Threads_GetNextToRun(int CPU) */ void Threads_SegFault(tVAddr Addr) { - //Threads_SendSignal( Proc_GetCurThread()->TID, SIGSEGV ); Warning("Thread #%i committed a segfault at address %p", Proc_GetCurThread()->TID, Addr); - Threads_Exit( 0, -1 ); + Threads_Fault( 1 ); + //Threads_Exit( 0, -1 ); +} + +/** + * \brief Acquire a heavy mutex + * \param Mutex Mutex to acquire + * + * This type of mutex checks if the mutex is avaliable, and acquires it + * if it is. Otherwise, the current thread is added to the mutex's wait + * queue and the thread suspends. When the holder of the mutex completes, + * the oldest thread (top thread) on the queue is given the lock and + * restarted. + */ +void Mutex_Acquire(tMutex *Mutex) +{ + tThread *us = Proc_GetCurThread(); + + // Get protector + SHORTLOCK( &Mutex->Protector ); + + //Log("Mutex_Acquire: (%p)", Mutex); + + // Check if the lock is already held + if( Mutex->Owner ) { + SHORTLOCK( &glThreadListLock ); + // - Remove from active list + us = Threads_RemActive(); + // - Mark as sleeping + us->Status = THREAD_STAT_OFFSLEEP; + + // - Add to waiting + if(Mutex->LastWaiting) { + Mutex->LastWaiting->Next = us; + Mutex->LastWaiting = us; + } + else { + Mutex->Waiting = us; + Mutex->LastWaiting = us; + } + SHORTREL( &glThreadListLock ); + SHORTREL( &Mutex->Protector ); + while(us->Status == THREAD_STAT_OFFSLEEP) Threads_Yield(); + // We're only woken when we get the lock + } + // Ooh, let's take it! + else { + Mutex->Owner = us; + SHORTREL( &Mutex->Protector ); + } +} + +/** + * \brief Release a held mutex + * \param Mutex Mutex to release + */ +void Mutex_Release(tMutex *Mutex) +{ + SHORTLOCK( &Mutex->Protector ); + //Log("Mutex_Release: (%p)", Mutex); + if( Mutex->Waiting ) { + Mutex->Owner = Mutex->Waiting; // Set owner + Mutex->Waiting = Mutex->Waiting->Next; // Next! + // Reset ->LastWaiting to NULL if we have just removed the last waiting thread + // 2010-10-02 21:50 - Comemerating the death of the longest single + // blocker in the Acess2 history. REMEMBER TO + // FUCKING MAINTAIN YOUR FUCKING LISTS DIPWIT + if( Mutex->LastWaiting == Mutex->Owner ) + Mutex->LastWaiting = NULL; + + // Wake new owner + SHORTLOCK( &glThreadListLock ); + if( Mutex->Owner->Status != THREAD_STAT_ACTIVE ) + Threads_AddActive(Mutex->Owner); + SHORTREL( &glThreadListLock ); + } + else { + Mutex->Owner = NULL; + } + SHORTREL( &Mutex->Protector ); +} + +/** + * \brief Is this mutex locked? + * \param Mutex Mutex pointer + */ +int Mutex_IsLocked(tMutex *Mutex) +{ + return Mutex->Owner != NULL; } // === EXPORTS === EXPORT(Threads_GetUID); +EXPORT(Threads_GetGID); +EXPORT(Mutex_Acquire); +EXPORT(Mutex_Release); +EXPORT(Mutex_IsLocked);