X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Fthreads.c;h=cafb8068d2d92471378c858fea516a1116a22b0a;hb=e573d30162c179edc6de7b7c8364a617d9f25f77;hp=5f2e3d7fc0354cde3b736d66c53dc23e39fc11b1;hpb=9d3800f60f2212432e550a4e003ae65b498a4d36;p=tpg%2Facess2.git diff --git a/Kernel/threads.c b/Kernel/threads.c index 5f2e3d7f..cafb8068 100644 --- a/Kernel/threads.c +++ b/Kernel/threads.c @@ -3,160 +3,226 @@ * threads.c * - Common Thread Control */ -#include +#include #include #include +#include + +// 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_LOTTERY // === CONSTANTS === #define DEFAULT_QUANTUM 10 -#define DEFAULT_TICKETS 5 -#define MAX_TICKETS 10 +#define DEFAULT_PRIORITY 5 +#define MIN_PRIORITY 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 int Proc_Clone(Uint *Err, Uint Flags); +extern void ArchThreads_Init(void); +extern void Proc_CallFaultHandler(tThread *Thread); +extern int GetCPUNum(void); // === PROTOTYPES === -void Threads_Init(); -void Threads_SetName(char *NewName); +void Threads_Init(void); +#if 0 + int Threads_SetName(const char *NewName); +#endif char *Threads_GetName(int ID); -void Threads_SetTickets(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); +#endif void Threads_AddToDelete(tThread *Thread); -tThread *Threads_int_GetPrev(tThread **List, 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 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); +#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); +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); + +#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 = { - 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: (char*)"ThreadZero", // Name + Quantum: DEFAULT_QUANTUM, // Default Quantum + Remaining: DEFAULT_QUANTUM, // Current Quantum + Priority: DEFAULT_PRIORITY // 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 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 === /** - * \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 + #if SCHEDULER_TYPE == SCHED_RR_PRI + gaActiveThreads[gThreadZero.Priority] = &gThreadZero; + #else gActiveThreads = &gThreadZero; - giTotalTickets = gThreadZero.NumTickets; - 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 + gAllThreads = &gThreadZero; + giNumActiveThreads = 1; + Proc_Start(); } /** - * \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 */ -void Threads_SetName(char *NewName) +int Threads_SetName(const 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) - * \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(int Num) +void Threads_SetPriority(tThread *Thread, int Pri) { - tThread *cur = Proc_GetCurThread(); - if(Num < 0) return; - if(Num > MAX_TICKETS) Num = MAX_TICKETS; + // Get current thread + if(Thread == NULL) Thread = Proc_GetCurThread(); + // Bounds checking + // - If < 0, set to lowest priority + if(Pri < 0) Pri = MIN_PRIORITY; + if(Pri > MIN_PRIORITY) Pri = MIN_PRIORITY; - LOCK( &giThreadListLock ); - giTotalTickets -= cur->NumTickets; - cur->NumTickets = Num; - giTotalTickets += Num; - //LOG("giTotalTickets = %i", giTotalTickets); - RELEASE( &giThreadListLock ); + // 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 ); + + #if SCHEDULER_TYPE == SCHED_LOTTERY + giFreeTickets -= caiTICKET_COUNTS[Thread->Priority] - caiTICKET_COUNTS[Pri]; + # if DEBUG_TRACE_TICKETS + Log("Threads_SetTickets: new giFreeTickets = %i", giFreeTickets); + # endif + #endif + Thread->Priority = Pri; + SHORTREL( &glThreadListLock ); + } + else + Thread->Priority = Pri; + #endif } /** * \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 +230,26 @@ 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) @@ -195,15 +263,11 @@ 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->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 +285,124 @@ 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; } /** - * \fn Uint *Threads_GetCfgPtr(int Id) + * \fn tThread *Threads_CloneTCB(Uint *Err, Uint Flags) + * \brief Clone the TCB of the current thread */ -Uint *Threads_GetCfgPtr(int Id) +tThread *Threads_CloneThreadZero(void) { - if(Id < 0 || Id >= NUM_CFG_ENTRIES) { - Warning("Threads_GetCfgPtr: Index %i is out of bounds", Id); + 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)); - return &Proc_GetCurThread()->Config[Id]; + 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 ); + + return new; +} + +/** + * \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) +{ + if(ID < 0 || ID >= NUM_CFG_ENTRIES) { + Warning("Threads_GetCfgPtr: Index %i is out of bounds", ID); + return NULL; + } + + 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; } @@ -264,18 +410,34 @@ int Threads_WaitTID(int TID, int *status) if(TID > 0) { tThread *t = Threads_GetThread(TID); int initStatus = t->Status; - int ret; - while(t->Status == initStatus) Threads_Yield(); - ret = t->RetStatus; + tTID ret; + + // 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); + } + } + + // 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; @@ -285,41 +447,36 @@ 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; - thread; - thread = thread->Next) - { - if(thread->TID == TID) - return thread; - } - - // Search Sleeping List - for(thread = gSleepingThreads; + // Search global list + for(thread = gAllThreads; 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; @@ -330,31 +487,42 @@ 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) { @@ -362,46 +530,41 @@ 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(); } /** * \fn void Threads_Kill(tThread *Thread, int Status) * \brief Kill a thread - * \param TID Thread ID (0 for current) + * \param Thread Thread to kill + * \param Status Status code to return to the parent */ void Threads_Kill(tThread *Thread, int Status) { - tThread *prev; tMsg *msg; + int isCurThread = Thread == Proc_GetCurThread(); - // Kill all children - #if 0 + // TODO: Kill all children + #if 1 { tThread *child; - for(child = gActiveThreads; + // TODO: I should keep a .Parent pointer, and a .Children list + for(child = gAllThreads; child; - child = child->Next) + child = child->GlobalNext) { - if(child->PTID == Thread->TID) + if(child->Parent == Thread) Threads_Kill(child, -1); } } #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 ) @@ -411,284 +574,993 @@ 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 --; - giTotalTickets -= Thread->NumTickets; + switch(Thread->Status) + { + 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 ; - // Mark thread as a zombie + default: + Log_Warning("Threads", "Threads_Kill - BUG Un-checked status (%i)", + Thread->Status); + break; + } + + // 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 ); } + Log("Thread %i went *hurk* (%i)", Thread->TID, Status); + // Release spinlocks - RELEASE( &Thread->IsLocked ); // Released first so that it IS released - RELEASE( &giThreadListLock ); - if(Status != -1) HALT(); + SHORTREL( &glThreadListLock ); + SHORTREL( &Thread->IsLocked ); // TODO: We may not actually be released... + + // And, reschedule + if(isCurThread) { + 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("Proc_Sleep - Current thread is not on the active queue"); - 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 ); - HALT(); + while(cur->Status != THREAD_STAT_ACTIVE) HALT(); } -/**c0108919: - * \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("Threads_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; + 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); - break; + Warning("Threads_Wake - Attempt to wake dead thread (%i)", Thread->TID); + return -ENOTIMPL; + default: - Warning("Thread_Wake - Unknown process status (%i)\n", Thread->Status); - break; + Warning("Threads_Wake - Unknown process status (%i)\n", Thread->Status); + 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( 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; + // Add to active list + #if SCHEDULER_TYPE == SCHED_RR_PRI + Thread->Next = gaActiveThreads[Thread->Priority]; + gaActiveThreads[Thread->Priority] = Thread; + #else Thread->Next = gActiveThreads; gActiveThreads = Thread; + #endif + + // Update bookkeeping giNumActiveThreads ++; - giTotalTickets += Thread->NumTickets; - //Log("Threads_AddActive: giNumActiveThreads = %i, giTotalTickets = %i", - // giNumActiveThreads, giTotalTickets); - RELEASE( &giThreadListLock ); + + #if SCHEDULER_TYPE == SCHED_LOTTERY + giFreeTickets += caiTICKET_COUNTS[ Thread->Priority ]; + # if DEBUG_TRACE_TICKETS + Log("Threads_AddActive: CPU%i %p %i (%s) added, new giFreeTickets = %i", + GetCPUNum(), Thread, Thread->TID, Thread->ThreadName, giFreeTickets); + # endif + #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 SCHEDULER_TYPE == SCHED_RR_PRI + if( !Threads_int_DelFromQueue(&gaActiveThreads[ret->Priority], ret) ) + #else + if( !Threads_int_DelFromQueue(&gActiveThreads, ret) ) + #endif + { + SHORTREL( &glThreadListLock ); + return NULL; + } + + ret->Next = NULL; + ret->Remaining = 0; + ret->CurCPU = -1; + + giNumActiveThreads --; + // no need to decrement tickets, scheduler did it for us + + #if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS + Log("Threads_RemActive: CPU%i %p %i (%s) removed, giFreeTickets = %i", + GetCPUNum(), ret, ret->TID, ret->ThreadName, giFreeTickets); + #endif + + SHORTREL( &glThreadListLock ); + + return ret; } /** - * \fn void Threads_SendSignal(int TID, int Num) - * \brief Send a signal to a thread + * \fn void Threads_SetFaultHandler(Uint Handler) + * \brief Sets the signal handler for a signal */ -void Threads_SendSignal(int TID, int Num) +void Threads_SetFaultHandler(Uint Handler) +{ + //Log_Debug("Threads", "Threads_SetFaultHandler: Handler = %p", Handler); + Proc_GetCurThread()->FaultHandler = Handler; +} + +/** + * \fn void Threads_Fault(int Num) + * \brief Calls a fault handler + */ +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); +} + +/** + * \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 ); } -#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) */ -void Threads_Dump() +void Threads_DumpActive(void) { tThread *thread; + #if SCHEDULER_TYPE == SCHED_RR_PRI + int i; + #endif + + Log("Active Threads: (%i reported)", giNumActiveThreads); - Log("Active Threads:"); - for(thread=gActiveThreads;thread;thread=thread->Next) + #if SCHEDULER_TYPE == SCHED_RR_PRI + for( i = 0; i < MIN_PRIORITY+1; i++ ) { - Log(" %i (%i) - %s", thread->TID, thread->TGID, thread->ThreadName); - 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 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); } } /** - * \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; - // Special case: 1 thread - if(giNumActiveThreads == 1) { - return gActiveThreads; + // 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 + // DEFINITELY - free() can deadlock in this case + while(gDeleteThreads) + { + thread = gDeleteThreads->Next; + // Only free if structure is unused + if( !IS_LOCKED(&gDeleteThreads->IsLocked) ) + { + // Set to dead + gDeleteThreads->Status = THREAD_STAT_BURIED; + // 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; } - //Log(" Threads_GetNextToRun: giNumActiveThreads=%i,giTotalTickets=%i", - // giNumActiveThreads, giTotalTickets); - // Get the ticket number - ticket = number = rand() % giTotalTickets; + // No active threads, just take a nap + if(giNumActiveThreads == 0) { + SHORTREL( &glThreadListLock ); + #if DEBUG_TRACE_TICKETS + Log("No active threads"); + #endif + return NULL; + } - //Log(" Threads_GetNextToRun: ticket = %i", ticket); + #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 - // Find the next thread - for(thread=gActiveThreads;thread;thread=thread->Next) - { - if(thread->NumTickets > number) break; - number -= thread->NumTickets; + // Allow the old thread to be scheduled again + if( Last ) { + if( Last->Status == THREAD_STAT_ACTIVE ) { + #if SCHEDULER_TYPE == SCHED_LOTTERY + giFreeTickets += caiTICKET_COUNTS[ Last->Priority ]; + # 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 + #endif + } + #if SCHEDULER_TYPE == SCHED_LOTTERY && 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; } - // Error Check - if(thread == 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) - number += thread->NumTickets; - Panic("Bookeeping Failed - giTotalTicketCount (%i) != true count (%i)", - giTotalTickets, number); + { + 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); + } + # if DEBUG_TRACE_TICKETS + LogF(" CPU%i giFreeTickets = %i, running %p (%i %s CPU=%i)\n", + CPU, giFreeTickets, thread, thread->TID, thread->ThreadName, thread->CurCPU); + # endif + + giFreeTickets -= caiTICKET_COUNTS[ thread->Priority ]; } + // --- + // Priority based round robin scheduler + // --- + #elif SCHEDULER_TYPE == SCHED_RR_PRI + { + 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( 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; + } + } + #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; + } + } + #else + # error "Unimplemented scheduling algorithm" + #endif + + // Make the new thread non-schedulable + thread->CurCPU = CPU; + + SHORTREL( &glThreadListLock ); + return thread; } /** - * \fn void Threads_SegFault(tVAddr Addr) - * \brief Called when a Segment Fault occurs + * \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 Threads_SegFault(tVAddr Addr) +int 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(); + us->Next = NULL; + // - Mark as sleeping + us->Status = THREAD_STAT_MUTEXSLEEP; + us->WaitPointer = Mutex; + + // - Add to waiting + if(Mutex->LastWaiting) { + Mutex->LastWaiting->Next = us; + Mutex->LastWaiting = us; + } + else { + Mutex->Waiting = us; + Mutex->LastWaiting = us; + } + #if 0 + { + int i = 0; + tThread *t; + for( t = Mutex->Waiting; t; t = t->Next, i++ ) + Log("[%i] (tMutex)%p->Waiting[%i] = %p (%i %s)", us->TID, Mutex, i, + t, t->TID, t->ThreadName); + } + #endif + + SHORTREL( &glThreadListLock ); + SHORTREL( &Mutex->Protector ); + while(us->Status == THREAD_STAT_MUTEXSLEEP) Threads_Yield(); + // We're only woken when we get the lock + us->WaitPointer = NULL; + } + // Ooh, let's take it! + else { + 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) +{ + 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 ); + + #if 0 + extern tMutex glPhysAlloc; + if( Mutex != &glPhysAlloc ) + LogF("Mutex %p released by %i %p\n", Mutex, Threads_GetTID(), __builtin_return_address(0)); + #endif +} + +/** + * \brief Is this mutex locked? + * \param Mutex Mutex pointer + */ +int Mutex_IsLocked(tMutex *Mutex) +{ + return Mutex->Owner != NULL; +} + +// +// Initialise a semaphore +// +void Semaphore_Init(tSemaphore *Sem, int Value, int MaxValue, const char *Module, const char *Name) +{ + Sem->Value = Value; + Sem->ModName = Module; + Sem->Name = Name; +} +// +// 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) { - //Threads_SendSignal( Proc_GetCurThread()->TID, SIGSEGV ); - Log("Thread #%i committed a segfault at address %p\n", Proc_GetCurThread()->TID, Addr); - Threads_Exit( 0, 0 ); + 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);