X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Fthreads.c;h=a8873988cfce2b54d2b657c9963cc1fd05bb10af;hb=e56e258bdc6345e33454ddb127b2d87c536a0f39;hp=99a9add67cfd68ec6c69fff2a7377248e9a4effa;hpb=2ae2035466cfa7816079a067ccee25e2b8bac6bc;p=tpg%2Facess2.git diff --git a/Kernel/threads.c b/Kernel/threads.c index 99a9add6..a8873988 100644 --- a/Kernel/threads.c +++ b/Kernel/threads.c @@ -5,77 +5,105 @@ */ #include #include +#include #include +#include +#include -#define DEBUG_TRACE_TICKETS 0 +// Configuration +#define DEBUG_TRACE_TICKETS 0 // Trace ticket counts +#define DEBUG_TRACE_STATE 0 // Trace state changes (sleep/wake) + +// --- Schedulers --- +#define SCHED_UNDEF 0 +#define SCHED_LOTTERY 1 // Lottery scheduler +#define SCHED_RR_SIM 2 // Single Queue Round Robin +#define SCHED_RR_PRI 3 // Multi Queue Round Robin +// Set scheduler type +#define SCHEDULER_TYPE SCHED_RR_PRI // === CONSTANTS === -#define DEFAULT_QUANTUM 10 -#define DEFAULT_TICKETS 5 -#define MAX_TICKETS 10 -const enum eConfigTypes cCONFIG_TYPES[] = { +#define DEFAULT_QUANTUM 5 +#define DEFAULT_PRIORITY 5 +#define MIN_PRIORITY 10 +const enum eConfigTypes cCONFIG_TYPES[NUM_CFG_ENTRIES] = { CFGT_HEAPSTR, // e.g. CFG_VFS_CWD CFGT_INT, // e.g. CFG_VFS_MAXFILES CFGT_NULL }; // === 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); // === PROTOTYPES === void Threads_Init(void); - int Threads_SetName(char *NewName); +#if 0 +void Threads_Delete(tThread *Thread); + int Threads_SetName(const char *NewName); +#endif char *Threads_GetName(int ID); -void Threads_SetTickets(tThread *Thread, int Num); +#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); -void Threads_AddToDelete(tThread *Thread); -tThread *Threads_int_GetPrev(tThread **List, tThread *Thread); +#endif +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); void Threads_Sleep(void); int Threads_Wake(tThread *Thread); void Threads_AddActive(tThread *Thread); +tThread *Threads_RemActive(void); +#endif +void Threads_ToggleTrace(int TID); +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 Mutex_Acquire(tMutex *Mutex); -void Mutex_Release(tMutex *Mutex); - int Mutex_IsLocked(tMutex *Mutex); +void Threads_DumpActive(void); // === GLOBALS === // -- Core Thread -- // Only used for the core kernel tThread gThreadZero = { - Status: THREAD_STAT_ACTIVE, // Status - ThreadName: "ThreadZero", // Name - Quantum: DEFAULT_QUANTUM, // Default Quantum - Remaining: DEFAULT_QUANTUM, // Current Quantum - NumTickets: DEFAULT_TICKETS // Number of tickets + .Status = THREAD_STAT_ACTIVE, // Status + .ThreadName = (char*)"ThreadZero", // Name + .Quantum = DEFAULT_QUANTUM, // Default Quantum + .Remaining = DEFAULT_QUANTUM, // Current Quantum + .Priority = DEFAULT_PRIORITY // Number of tickets }; // -- Processes -- // --- Locks --- tShortSpinlock glThreadListLock; ///\note NEVER use a heap function while locked // --- Current State --- -volatile int giNumActiveThreads = 0; -//volatile int giTotalTickets = 0; -volatile int giFreeTickets = 0; -volatile Uint giNextTID = 1; +volatile int giNumActiveThreads = 0; // Number of threads on the active queue +volatile Uint giNextTID = 1; // Next TID to allocate // --- Thread Lists --- -tThread *gActiveThreads = NULL; // Currently Running Threads +tThread *gAllThreads = NULL; // All allocated 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) +// --- Scheduler Types --- +#if SCHEDULER_TYPE == SCHED_LOTTERY +const int caiTICKET_COUNTS[MIN_PRIORITY+1] = {100,81,64,49,36,25,16,9,4,1,0}; +volatile int giFreeTickets = 0; // Number of tickets held by non-scheduled threads +tThread *gActiveThreads = NULL; // Currently Running Threads +#elif SCHEDULER_TYPE == SCHED_RR_SIM +tThread *gActiveThreads = NULL; // Currently Running Threads +#elif SCHEDULER_TYPE == SCHED_RR_PRI +tThread *gaActiveThreads[MIN_PRIORITY+1]; // Active threads for each priority level +#else +# error "Unkown scheduler type" +#endif // === CODE === /** @@ -86,23 +114,59 @@ void Threads_Init(void) { ArchThreads_Init(); + Log_Debug("Threads", "Offsets of tThread"); + Log_Debug("Threads", ".Priority = %i", offsetof(tThread, Priority)); + Log_Debug("Threads", ".KernelStack = %i", offsetof(tThread, KernelStack)); + // Create Initial Task + #if SCHEDULER_TYPE == SCHED_RR_PRI + gaActiveThreads[gThreadZero.Priority] = &gThreadZero; + #else gActiveThreads = &gThreadZero; - //giFreeTickets = gThreadZero.NumTickets; + #endif + + gAllThreads = &gThreadZero; giNumActiveThreads = 1; Proc_Start(); } +void Threads_Delete(tThread *Thread) +{ + // Set to dead + Thread->Status = THREAD_STAT_BURIED; + + // Clear out process state + Proc_ClearThread(Thread); + + // Free name + if( IsHeap(Thread->ThreadName) ) + free(Thread->ThreadName); + + // Remove from global list + // TODO: Lock this too + if( Thread == gAllThreads ) + gAllThreads = Thread->GlobalNext; + else + Thread->GlobalPrev->GlobalNext = Thread->GlobalNext; + + free(Thread); +} + /** - * \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; + // 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 ); @@ -114,62 +178,99 @@ int Threads_SetName(char *NewName) /** * \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; } - // TODO: Find a thread and get its name - return NULL; + return Threads_GetThread(ID)->ThreadName; } /** - * \fn void Threads_SetTickets(tThread *Thread, int Num) - * \brief Sets the 'priority' of a task + * \fn void Threads_SetPriority(tThread *Thread, int Pri) + * \brief Sets the priority of a task + * \param Thread Thread to update ticket count (NULL means current thread) + * \param Pri New priority */ -void Threads_SetTickets(tThread *Thread, int Num) +void Threads_SetPriority(tThread *Thread, int Pri) { - if(Thread == NULL) - Thread = Proc_GetCurThread(); - if(Num < 0) return; - if(Num > MAX_TICKETS) Num = MAX_TICKETS; - - if( Thread != Proc_GetCurThread() ) { + // Get current thread + if(Thread == NULL) Thread = Proc_GetCurThread(); + // Bounds checking + // - If < 0, set to lowest priority + // - Minumum priority is actualy a high number, 0 is highest + if(Pri < 0) Pri = MIN_PRIORITY; + if(Pri > MIN_PRIORITY) Pri = MIN_PRIORITY; + + // Do we actually have to do anything? + if( Pri == Thread->Priority ) return; + + #if SCHEDULER_TYPE == SCHED_RR_PRI + SHORTLOCK( &glThreadListLock ); + // Remove from old priority + Threads_int_DelFromQueue( &gaActiveThreads[Thread->Priority], Thread ); + // And add to new + Thread->Next = gaActiveThreads[Pri]; + gaActiveThreads[Pri] = Thread; + Thread->Priority = Pri; + SHORTREL( &glThreadListLock ); + #else + // 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 SCHEDULER_TYPE == SCHED_LOTTERY + giFreeTickets -= caiTICKET_COUNTS[Thread->Priority] - caiTICKET_COUNTS[Pri]; + # if DEBUG_TRACE_TICKETS + Log("Threads_SetTickets: new giFreeTickets = %i [-%i+%i]", + giFreeTickets, + caiTICKET_COUNTS[Thread->Priority], caiTICKET_COUNTS[Pri]); + # endif + #endif + Thread->Priority = Pri; SHORTREL( &glThreadListLock ); } else - Thread->NumTickets = Num; + Thread->Priority = Pri; + #endif + + #if DEBUG_TRACE_STATE + Log("Threads_SetPriority: %p(%i %s) pri set %i", + Thread, Thread->TID, Thread->ThreadName, + Pri); + #endif } /** - * \fn tThread *Threads_CloneTCB(Uint *Err, Uint Flags) + * \brief Clone the TCB of the current thread + * \param Flags Flags for something... (What is this for?) */ -tThread *Threads_CloneTCB(Uint *Err, Uint Flags) +tThread *Threads_CloneTCB(Uint Flags) { tThread *cur, *new; int i; cur = Proc_GetCurThread(); + // Allocate and duplicate new = malloc(sizeof(tThread)); - if(new == NULL) { - *Err = -ENOMEM; - return NULL; - } + if(new == NULL) { errno = -ENOMEM; return NULL; } memcpy(new, cur, sizeof(tThread)); new->CurCPU = -1; new->Next = NULL; memset( &new->IsLocked, 0, sizeof(new->IsLocked)); - new->Status = THREAD_STAT_ACTIVE; + new->Status = THREAD_STAT_PREINIT; new->RetStatus = 0; // Get Thread ID new->TID = giNextTID++; - new->PTID = cur->TID; + new->Parent = cur; + new->bInstrTrace = 0; // Clone Name new->ThreadName = strdup(cur->ThreadName); @@ -186,7 +287,7 @@ tThread *Threads_CloneTCB(Uint *Err, Uint Flags) // Set State new->Remaining = new->Quantum = cur->Quantum; - new->NumTickets = cur->NumTickets; + new->Priority = cur->Priority; // Set Signal Handlers new->CurFaultNum = 0; @@ -208,67 +309,142 @@ 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->GlobalPrev = new; + gAllThreads = new; + SHORTREL( &glThreadListLock ); + + return new; +} + +/** + * \brief Clone the TCB of the kernel thread + */ +tThread *Threads_CloneThreadZero(void) +{ + tThread *new; + int i; + + // 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 = DEFAULT_QUANTUM; + new->Priority = DEFAULT_PRIORITY; + new->bInstrTrace = 0; + + // Set Signal Handlers + new->CurFaultNum = 0; + new->FaultHandler = 0; + + for( i = 0; i < NUM_CFG_ENTRIES; i ++ ) + { + new->Config[i] = 0; + } + + // Maintain a global list of threads + SHORTLOCK( &glThreadListLock ); + new->GlobalPrev = NULL; // Protect against bugs + new->GlobalNext = gAllThreads; + gAllThreads->GlobalPrev = new; + 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; } // Specific Thread 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! + // 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 + ret = t->TID; switch(t->Status) { case THREAD_STAT_ZOMBIE: + // Kill the thread t->Status = THREAD_STAT_DEAD; - if(status) *status = 0; - Threads_AddToDelete( t ); + // TODO: Child return value? + if(Status) *Status = t->RetStatus; + // add to delete queue + Threads_Delete( t ); break; default: - if(status) *status = -1; + if(Status) *Status = -1; break; } return ret; @@ -278,77 +454,65 @@ 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 + * \brief Deletes an entry from a list + * \param List Pointer to the list head + * \param Thread Thread to find + * \return \a Thread */ -void Threads_AddToDelete(tThread *Thread) +tThread *Threads_int_DelFromQueue(tThread **List, tThread *Thread) { - // Add to delete queue - if(gDeleteThreads) { - Thread->Next = gDeleteThreads; - gDeleteThreads = Thread; - } else { - Thread->Next = NULL; - gDeleteThreads = Thread; + 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; } -} - -/** - * \fn tThread *Threads_int_GetPrev(tThread **List, tThread *Thread) - * \brief Gets the previous entry in a thead linked list - */ -tThread *Threads_int_GetPrev(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; - } + + if( !prev ) { + *List = Thread->Next; + //LogF("%p(%s) removed from head of %p\n", Thread, Thread->ThreadName, List); } - return ret; + 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) { @@ -356,9 +520,9 @@ void Threads_Exit(int TID, int Status) Threads_Kill( Proc_GetCurThread(), (Uint)Status & 0xFF ); else Threads_Kill( Threads_GetThread(TID), (Uint)Status & 0xFF ); + // Halt forever, just in case - for(;;) - HALT(); + for(;;) HALT(); } /** @@ -369,19 +533,20 @@ void Threads_Exit(int TID, int Status) */ void Threads_Kill(tThread *Thread, int Status) { - tThread *prev; tMsg *msg; + int isCurThread = Thread == Proc_GetCurThread(); - // Kill all children - #if 0 + // TODO: Disown all children? + #if 1 { tThread *child; - for(child = gActiveThreads; + // TODO: I should keep a .Children list + for(child = gAllThreads; child; - child = child->Next) + child = child->GlobalNext) { - if(child->PTID == Thread->TID) - Threads_Kill(child, -1); + if(child->Parent == Thread) + child->Parent = &gThreadZero; } } #endif @@ -391,18 +556,6 @@ void Threads_Kill(tThread *Thread, int Status) // Lock thread (stop us recieving messages) SHORTLOCK( &Thread->IsLocked ); - // Lock thread list - SHORTLOCK( &glThreadListLock ); - - // Get previous thread on list - prev = Threads_int_GetPrev( &gActiveThreads, Thread ); - if(!prev) { - Warning("Proc_Exit - Current thread is not on the active queue"); - Thread->IsLocked.Lock = 0; // We can't use SHORTREL as that starts IRQs again - SHORTREL( &glThreadListLock ); - return; - } - // Clear Message Queue while( Thread->Messages ) { @@ -411,44 +564,93 @@ void Threads_Kill(tThread *Thread, int Status) Thread->Messages = msg; } - Thread->Remaining = 0; // Clear Remaining Quantum - Thread->Quantum = 0; // Clear Quantum to indicate dead thread - prev->Next = Thread->Next; // Remove from active + // Lock thread list + SHORTLOCK( &glThreadListLock ); - giNumActiveThreads --; - if( Thread != Proc_GetCurThread() ) - giFreeTickets -= Thread->NumTickets; - //Log("Threads_Kill: giFreeTickets = %i", giFreeTickets); + switch(Thread->Status) + { + case THREAD_STAT_PREINIT: // Only on main list + break; - // Mark thread as a zombie - Thread->RetStatus = Status; + // 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; - // Don't Zombie if we are being killed as part of a tree - if(Status == -1) - { - Thread->Status = THREAD_STAT_DEAD; - Threads_AddToDelete( Thread ); - } else { - Thread->Status = THREAD_STAT_ZOMBIE; + // Brains!... You cannot kill something that is already dead + 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 ; + + default: + Log_Warning("Threads", "Threads_Kill - BUG Un-checked status (%i)", + Thread->Status); + break; } - // Release spinlocks - Thread->IsLocked.Lock = 0; // Released first so that it IS released + // Save exit status + Thread->RetStatus = Status; + + SHORTREL( &Thread->IsLocked ); + + Thread->Status = THREAD_STAT_ZOMBIE; SHORTREL( &glThreadListLock ); + // TODO: Send something like SIGCHLD + Threads_Wake( Thread->Parent ); - //Log("Thread %i went *hurk*", Thread->TID); + Log("Thread %i went *hurk* (%i)", Thread->TID, Status); - if(Status != -1) HALT(); + // And, reschedule + if(isCurThread) + { + for( ;; ) + Proc_Reschedule(); + } } /** - * \fn void Threads_Yield(void) - * \brief Yield remainder of timeslice + * \brief Yield remainder of the current thread's timeslice */ void Threads_Yield(void) { - Proc_GetCurThread()->Remaining = 0; - HALT(); +// Log("Threads_Yield: by %p", __builtin_return_address(0)); + Proc_Reschedule(); } /** @@ -458,96 +660,130 @@ void Threads_Yield(void) void Threads_Sleep(void) { tThread *cur = Proc_GetCurThread(); - tThread *thread; - - //Log_Log("Threads", "%i going to sleep", cur->TID); // Acquire Spinlock SHORTLOCK( &glThreadListLock ); - // 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(); - SHORTREL( &glThreadListLock ); - return; - } - // Don't sleep if there is a message waiting if( cur->Messages ) { 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 --; - // - No need to alter giFreeTickets (we're being executed) - // 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 SHORTREL( &glThreadListLock ); - - while(cur->Status != THREAD_STAT_ACTIVE) HALT(); + + while(cur->Status != THREAD_STAT_ACTIVE) { + Proc_Reschedule(); + if( cur->Status != THREAD_STAT_ACTIVE ) + Log("%i - Huh? why am I up? zzzz...", cur->TID); + } } /** - * \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 */ int Threads_Wake(tThread *Thread) { - tThread *prev; - if(!Thread) return -EINVAL; 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: // TODO: Comment better - //Log_Log("Threads", "Waking %i (%p) from sleeping (CPU=%i)", - // Thread->TID, Thread, Thread->CurCPU); + + case THREAD_STAT_SLEEPING: SHORTLOCK( &glThreadListLock ); - prev = Threads_int_GetPrev(&gSleepingThreads, Thread); - prev->Next = Thread->Next; // Remove from sleeping queue - Thread->Next = gActiveThreads; // Add to active queue - gActiveThreads = Thread; - giNumActiveThreads ++; - // Thread can't be the current, so no need to check - Thread->CurCPU = -1; - giFreeTickets += Thread->NumTickets; - #if DEBUG_TRACE_TICKETS - Log("Threads_Wake: giFreeTickets = %i", giFreeTickets); - #endif - Thread->Status = THREAD_STAT_ACTIVE; + // Remove from sleeping queue + Threads_int_DelFromQueue(&gSleepingThreads, Thread); + SHORTREL( &glThreadListLock ); + Threads_AddActive( Thread ); + + #if DEBUG_TRACE_STATE + Log("Threads_Sleep: %p (%i %s) woken", Thread, Thread->TID, Thread->ThreadName); + #endif return -EOK; + + case THREAD_STAT_SEMAPHORESLEEP: { + tSemaphore *sem; + tThread *th, *prev=NULL; + + sem = Thread->WaitPointer; + + SHORTLOCK( &sem->Protector ); + + // Remove from sleeping queue + for( th = sem->Waiting; th; prev = th, th = th->Next ) + if( th == Thread ) break; + if( th ) + { + if(prev) + prev->Next = Thread->Next; + else + sem->Waiting = Thread->Next; + if(sem->LastWaiting == Thread) + sem->LastWaiting = prev; + } + else + { + prev = NULL; + for( th = sem->Signaling; th; prev = th, th = th->Next ) + if( th == Thread ) break; + if( !th ) { + Log_Warning("Threads", "Thread %p(%i %s) is not on semaphore %p(%s:%s)", + Thread, Thread->TID, Thread->ThreadName, + sem, sem->ModName, sem->Name); + return -EINTERNAL; + } + + if(prev) + prev->Next = Thread->Next; + else + sem->Signaling = Thread->Next; + if(sem->LastSignaling == Thread) + sem->LastSignaling = prev; + } + + Thread->RetStatus = 0; // It didn't get anything + Threads_AddActive( Thread ); + + #if DEBUG_TRACE_STATE + Log("Threads_Sleep: %p(%i %s) woken from semaphore", Thread, Thread->TID, Thread->ThreadName); + #endif + SHORTREL( &sem->Protector ); + } 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; } } @@ -560,36 +796,133 @@ int Threads_Wake(tThread *Thread) int Threads_WakeTID(tTID TID) { tThread *thread = Threads_GetThread(TID); + int ret; if(!thread) return -ENOENT; - return Threads_Wake( thread ); + ret = Threads_Wake( thread ); + //Log_Debug("Threads", "TID %i woke %i (%p)", Threads_GetTID(), TID, thread); + return ret; +} + +void Threads_ToggleTrace(int TID) +{ + tThread *thread = Threads_GetThread(TID); + if(!thread) return ; + thread->bInstrTrace = !thread->bInstrTrace; } /** - * \fn void Threads_AddActive(tThread *Thread) * \brief Adds a thread to the active queue */ void Threads_AddActive(tThread *Thread) { SHORTLOCK( &glThreadListLock ); - Thread->Next = gActiveThreads; - gActiveThreads = Thread; + + if( Thread->Status == THREAD_STAT_ACTIVE ) { + tThread *cur = Proc_GetCurThread(); + Log_Warning("Threads", "WTF, %p CPU%i %p (%i %s) is adding %p (%i %s) when it is active", + __builtin_return_address(0), + GetCPUNum(), cur, cur->TID, cur->ThreadName, Thread, Thread->TID, Thread->ThreadName); + SHORTREL( &glThreadListLock ); + return ; + } + + // Set state + Thread->Status = THREAD_STAT_ACTIVE; +// Thread->CurCPU = -1; + // Add to active list + { + tThread *tmp, *prev = NULL; + #if SCHEDULER_TYPE == SCHED_RR_PRI + for( tmp = gaActiveThreads[Thread->Priority]; tmp; prev = tmp, tmp = tmp->Next ); + if(prev) + prev->Next = Thread; + else + gaActiveThreads[Thread->Priority] = Thread; + #else + for( tmp = gActiveThreads; tmp; prev = tmp, tmp = tmp->Next ); + if(prev) + prev->Next = Thread; + else + gActiveThreads = Thread; + #endif + Thread->Next = NULL; + } + + // Update bookkeeping giNumActiveThreads ++; - // Thread can't be the current, so no need to check - giFreeTickets += Thread->NumTickets; - #if DEBUG_TRACE_TICKETS - Log("Threads_AddActive: giFreeTickets = %i", giFreeTickets); + + #if SCHEDULER_TYPE == SCHED_LOTTERY + { + int delta; + // Only change the ticket count if the thread is un-scheduled + if(Thread->CurCPU != -1) + delta = 0; + else + delta = caiTICKET_COUNTS[ Thread->Priority ]; + + giFreeTickets += delta; + # if DEBUG_TRACE_TICKETS + Log("CPU%i %p (%i %s) added, new giFreeTickets = %i [+%i]", + GetCPUNum(), Thread, Thread->TID, Thread->ThreadName, + giFreeTickets, delta + ); + # endif + } #endif + SHORTREL( &glThreadListLock ); } +/** + * \brief Removes the current thread from the active queue + * \warning This should ONLY be called with the lock held + * \return Current thread pointer + */ +tThread *Threads_RemActive(void) +{ + tThread *ret = Proc_GetCurThread(); + + if( !IS_LOCKED(&glThreadListLock) ) { + Log_KernelPanic("Threads", "Threads_RemActive called without lock held"); + return NULL; + } + + // Delete from active queue + #if SCHEDULER_TYPE == SCHED_RR_PRI + if( !Threads_int_DelFromQueue(&gaActiveThreads[ret->Priority], ret) ) + #else + if( !Threads_int_DelFromQueue(&gActiveThreads, ret) ) + #endif + { + SHORTREL( &glThreadListLock ); + Log_Warning("Threads", "Current thread %p(%i %s) is not on active queue", + ret, ret->TID, ret->ThreadName + ); + return NULL; + } + + ret->Next = NULL; + ret->Remaining = 0; + + giNumActiveThreads --; + // no need to decrement tickets, scheduler did it for us + + #if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS + Log("CPU%i %p (%i %s) removed, giFreeTickets = %i [nc]", + GetCPUNum(), ret, ret->TID, ret->ThreadName, giFreeTickets); + #endif + + return ret; +} + /** * \fn void Threads_SetFaultHandler(Uint Handler) * \brief Sets the signal handler for a signal */ void Threads_SetFaultHandler(Uint Handler) { - Log_Log("Threads", "Threads_SetFaultHandler: Handler = %p", Handler); + //Log_Debug("Threads", "Threads_SetFaultHandler: Handler = %p", Handler); Proc_GetCurThread()->FaultHandler = Handler; } @@ -601,8 +934,6 @@ void Threads_Fault(int Num) { tThread *thread = Proc_GetCurThread(); - Log_Log("Threads", "Threads_Fault: thread = %p", thread); - if(!thread) return ; Log_Log("Threads", "Threads_Fault: thread->FaultHandler = %p", thread->FaultHandler); @@ -621,6 +952,7 @@ void Threads_Fault(int Num) // Double Fault? Oh, F**k if(thread->CurFaultNum != 0) { + Log_Warning("Threads", "Threads_Fault: Double fault on %i", thread->TID); Threads_Kill(thread, -1); // For now, just kill HALT(); } @@ -630,6 +962,20 @@ void Threads_Fault(int Num) Proc_CallFaultHandler(thread); } +/** + * \fn void Threads_SegFault(tVAddr Addr) + * \brief Called when a Segment Fault occurs + */ +void Threads_SegFault(tVAddr Addr) +{ + tThread *cur = Proc_GetCurThread(); + cur->bInstrTrace = 0; + Log_Warning("Threads", "Thread #%i committed a segfault at address %p", cur->TID, Addr); + MM_DumpTables(0, USER_MAX); + Threads_Fault( 1 ); + //Threads_Exit( 0, -1 ); +} + // --- Process Structure Access Functions --- tPID Threads_GetPID(void) { @@ -655,7 +1001,7 @@ int Threads_SetUID(Uint *Errno, tUID ID) *Errno = -EACCES; return -1; } - Log("Threads_SetUID - Setting User ID to %i", ID); + Log_Debug("Threads", "TID %i's UID set to %i", t->TID, ID); t->UID = ID; return 0; } @@ -667,39 +1013,90 @@ int Threads_SetGID(Uint *Errno, tGID ID) *Errno = -EACCES; return -1; } - Log("Threads_SetGID - Setting Group ID to %i", ID); + Log_Debug("Threads", "TID %i's GID set to %i", t->TID, ID); t->GID = ID; return 0; } /** * \fn void Threads_Dump(void) - * \brief Dums a list of currently running threads */ -void Threads_Dump(void) +void Threads_DumpActive(void) { tThread *thread; + #if SCHEDULER_TYPE == SCHED_RR_PRI + int i; + #endif - Log("Active Threads:"); - for(thread=gActiveThreads;thread;thread=thread->Next) + Log("Active Threads: (%i reported)", giNumActiveThreads); + + #if SCHEDULER_TYPE == SCHED_RR_PRI + for( i = 0; i < MIN_PRIORITY+1; i++ ) { - Log(" %i (%i) - %s (CPU %i)", - thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU); - Log(" %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum); - Log(" KStack 0x%x", thread->KernelStack); + for(thread=gaActiveThreads[i];thread;thread=thread->Next) + #else + for(thread=gActiveThreads;thread;thread=thread->Next) + #endif + { + Log(" %p %i (%i) - %s (CPU %i)", + thread, 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(" Priority %i, Quantum %i", thread->Priority, thread->Quantum); + Log(" KStack 0x%x", thread->KernelStack); + if( thread->bInstrTrace ) + Log(" Tracing Enabled"); + Proc_DumpThreadCPUState(thread); + } + + #if SCHEDULER_TYPE == SCHED_RR_PRI } - Log("Sleeping Threads:"); - for(thread=gSleepingThreads;thread;thread=thread->Next) + #endif +} + +/** + * \fn void Threads_Dump(void) + * \brief Dumps a list of currently running threads + */ +void Threads_Dump(void) +{ + tThread *thread; + + Log("--- Thread Dump ---"); + Threads_DumpActive(); + + Log("All Threads:"); + for(thread=gAllThreads;thread;thread=thread->GlobalNext) { - Log(" %i (%i) - %s", - thread->TID, thread->TGID, thread->ThreadName); - Log(" %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum); + Log(" %p %i (%i) - %s (CPU %i)", + thread, thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU); + Log(" State %i (%s)", thread->Status, casTHREAD_STAT[thread->Status]); + switch(thread->Status) + { + 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; + default: break; + } + Log(" Priority %i, Quantum %i", thread->Priority, thread->Quantum); Log(" KStack 0x%x", thread->KernelStack); + if( thread->bInstrTrace ) + Log(" Tracing Enabled"); + Proc_DumpThreadCPUState(thread); } } /** - * \fn tThread *Threads_GetNextToRun(int CPU, tThread *Last) * \brief Gets the next thread to run * \param CPU Current CPU * \param Last The thread the CPU was running @@ -707,219 +1104,201 @@ void Threads_Dump(void) tThread *Threads_GetNextToRun(int CPU, tThread *Last) { tThread *thread; - int ticket; - int number; - // TODO: Enable the code to tell if the current CPU has the lock or - // another does. - - // Check if the thread list is locked by other code - // - If so, don't switch (give it a chance to complete) - if( IS_LOCKED(&glThreadListLock) ) + // If this CPU has the lock, we must let it complete + if( CPU_HAS_LOCK( &glThreadListLock ) ) return Last; - // Clear Delete Queue - while(gDeleteThreads) - { - thread = gDeleteThreads->Next; - if( IS_LOCKED(&gDeleteThreads->IsLocked) ) { // Only free if structure is unused - gDeleteThreads->Status = THREAD_STAT_NULL; - free( gDeleteThreads ); - } - gDeleteThreads = thread; - } + // Don't change threads if the current CPU has switches disabled + if( gaThreads_NoTaskSwitch[CPU] ) + return Last; + + // Lock thread list + SHORTLOCK( &glThreadListLock ); + // Make sure the current (well, old) thread is marked as de-scheduled + if(Last) Last->CurCPU = -1; + // No active threads, just take a nap if(giNumActiveThreads == 0) { + SHORTREL( &glThreadListLock ); #if DEBUG_TRACE_TICKETS Log("No active threads"); #endif return NULL; } - // Lock thread list - // - HLT lock (Used because only another CPU can obtain the lock, - // but it has a potentially long lock period) - // - Well, this CPU can obtain the lock, but that is aliveviated by - // the above. - SHORTLOCK( &glThreadListLock ); - + #if SCHEDULER_TYPE != SCHED_RR_PRI // Special case: 1 thread if(giNumActiveThreads == 1) { if( gActiveThreads->CurCPU == -1 ) gActiveThreads->CurCPU = CPU; + SHORTREL( &glThreadListLock ); + if( gActiveThreads->CurCPU == CPU ) return gActiveThreads; + return NULL; // CPU has nothing to do } + #endif // 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 (%s) into the pool (%i tickets in pool)\n", - CPU, Last, Last->ThreadName, Last->NumTickets); + #if SCHEDULER_TYPE == SCHED_LOTTERY + giFreeTickets += caiTICKET_COUNTS[ Last->Priority ]; + # if DEBUG_TRACE_TICKETS + LogF("Log: CPU%i released %p (%i %s) into the pool (%i [+%i] tickets in pool)\n", + CPU, Last, Last->TID, Last->ThreadName, giFreeTickets, + caiTICKET_COUNTS[ Last->Priority ]); + # endif #endif } - #if DEBUG_TRACE_TICKETS + #if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS else - LogF(" %p (%s)->Status = %i\n", Last, Last->ThreadName, Last->Status); + LogF("Log: CPU%i released %p (%i %s)->Status = %i (Released,not in pool)\n", + CPU, Last, Last->TID, Last->ThreadName, Last->Status); #endif Last->CurCPU = -1; } - #if 1 - number = 0; - for(thread=gActiveThreads;thread;thread=thread->Next) { - if(thread->CurCPU >= 0) continue; - number += thread->NumTickets; - } - if(number != giFreeTickets) { - Panic("Bookkeeping fail (giFreeTickets(%i) != number(%i)) - CPU%i", - giFreeTickets, number, CPU); - } - #endif - - // No free tickets (all tasks delegated to cores) - if( giFreeTickets == 0 ) { - SHORTREL(&glThreadListLock); - return NULL; + // --- + // Lottery Scheduler + // --- + #if SCHEDULER_TYPE == SCHED_LOTTERY + { + int ticket, number; + # 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 += caiTICKET_COUNTS[ thread->Priority ]; + } + if(number != giFreeTickets) { + Panic("Bookkeeping fail (giFreeTickets(%i) != number(%i)) - CPU%i", + giFreeTickets, number, CPU); + } + # endif + + // 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( caiTICKET_COUNTS[ thread->Priority ] > number) break; + number -= caiTICKET_COUNTS[ thread->Priority ]; + } + + // If we didn't find a thread, something went wrong + if(thread == NULL) + { + number = 0; + for(thread=gActiveThreads;thread;thread=thread->Next) { + if(thread->CurCPU >= 0) continue; + number += caiTICKET_COUNTS[ thread->Priority ]; + } + Panic("Bookeeping Failed - giFreeTickets(%i) > true count (%i)", + giFreeTickets, number); + } + + giFreeTickets -= caiTICKET_COUNTS[ thread->Priority ]; + # if DEBUG_TRACE_TICKETS + LogF("Log: CPU%i allocated %p (%i %s), (%i [-%i] tickets in pool), \n", + CPU, thread, thread->TID, thread->ThreadName, + giFreeTickets, caiTICKET_COUNTS[ thread->Priority ]); + # endif } - // Get the ticket number - ticket = number = rand() % giFreeTickets; - - // Find the next thread - for(thread=gActiveThreads;thread;thread=thread->Next) + // --- + // Priority based round robin scheduler + // --- + #elif SCHEDULER_TYPE == SCHED_RR_PRI { - if(thread->CurCPU >= 0) continue; - if(thread->NumTickets > number) break; - number -= thread->NumTickets; + int i; + for( i = 0; i < MIN_PRIORITY + 1; i ++ ) + { + for(thread = gaActiveThreads[i]; thread; thread = thread->Next) + { + if( thread->CurCPU == -1 ) break; + } + // If we fall onto the same queue again, special handling is + // needed + if( Last && Last->Status == THREAD_STAT_ACTIVE && i == Last->Priority ) { + tThread *savedThread = thread; + + // Find the next unscheduled thread in the list + for( thread = Last->Next; thread; thread = thread->Next ) + { + if( thread->CurCPU == -1 ) break; + } + // If we don't find anything after, just use the one + // found above. + if( !thread ) thread = savedThread; + } + // Found a thread? Schedule it! + if( thread ) break; + } + + // Anything to do? + if( !thread ) { + SHORTREL(&glThreadListLock); + return NULL; + } + if( thread->Status != THREAD_STAT_ACTIVE ) { + LogF("Oops, Thread %i (%s) is not active\n", thread->TID, thread->ThreadName); + } } - // Error Check - if(thread == NULL) - { - number = 0; - for(thread=gActiveThreads;thread;thread=thread->Next) { - if(thread->CurCPU >= 0) continue; - number += thread->NumTickets; + #elif SCHEDULER_TYPE == SCHED_RR_SIM + { + // Find the next unscheduled thread in the list + for( thread = Last->Next; thread; thread = thread->Next ) + { + if( thread->CurCPU == -1 ) break; + } + // If we don't find anything after, search from the beginning + if( !thread ) + { + for(thread = gActiveThreads; thread; thread = thread->Next) + { + if( thread->CurCPU == -1 ) break; + } + } + + // Anything to do? + if( !thread ) { + SHORTREL(&glThreadListLock); + return NULL; } - Panic("Bookeeping Failed - giFreeTickets(%i) > true count (%i)", - giFreeTickets, number); } - #if DEBUG_TRACE_TICKETS - LogF(" CPU%i giFreeTickets = %i\n", CPU, giFreeTickets); + #else + # error "Unimplemented scheduling algorithm" #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 (%s CPU=%i)\n", - CPU, giFreeTickets, thread, thread->ThreadName, thread->CurCPU); - #endif + thread->Remaining = thread->Quantum; SHORTREL( &glThreadListLock ); 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 - * - * 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(); - tThread *prev; - - // 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->Remaining = 0; - prev = Threads_int_GetPrev(&gActiveThreads, us); - prev->Next = us->Next; - giNumActiveThreads --; - us->Status = THREAD_STAT_SLEEPING; - - // - 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_SLEEPING) HALT(); - // 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! - // Wake new owner - Mutex->Owner->Status = THREAD_STAT_ACTIVE; - Threads_AddActive(Mutex->Owner); - Log("Mutex %p Woke %p", Mutex, Mutex->Owner); - } - 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);