X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Fthreads.c;h=78e53ac52d81460cdd7602b55027262f365f8b21;hb=e31829ecc2b8ae2338745f4ed393748704a81531;hp=f726f27586f444c71ee45b1d7ebdbd4919ff1053;hpb=814b2d0009da73b56c6def5d70a9dd97c7b17e2e;p=tpg%2Facess2.git diff --git a/Kernel/threads.c b/Kernel/threads.c index f726f275..78e53ac5 100644 --- a/Kernel/threads.c +++ b/Kernel/threads.c @@ -5,187 +5,261 @@ */ #include #include +#include #include +#include +#include +#include + +// Configuration +#define DEBUG_TRACE_TICKETS 0 // Trace ticket counts +#define DEBUG_TRACE_STATE 0 // Trace state changes (sleep/wake) +#define SEMAPHORE_DEBUG 0 + +// --- 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 +#define DEFAULT_QUANTUM 5 +#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 Proc_CallFaultHandler(tThread *Thread); // === PROTOTYPES === -void Threads_Init(); - int 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(); -tUID Threads_GetUID(); +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); +tGID Threads_GetGID(void); int Threads_SetUID(Uint *Errno, tUID ID); -tGID Threads_GetGID(); int Threads_SetGID(Uint *Errno, tUID ID); -void Threads_Dump(); +#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, // Current Fault, Fault Handler - - 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(); + 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; - 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 */ -int 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 + // - 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 ); + + #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->Priority = Pri; + #endif - LOCK( &giThreadListLock ); - giTotalTickets -= cur->NumTickets; - cur->NumTickets = Num; - giTotalTickets += Num; - //LOG("giTotalTickets = %i", giTotalTickets); - RELEASE( &giThreadListLock ); + #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; - 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; + new->bInstrTrace = 0; // 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) @@ -199,7 +273,7 @@ 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; @@ -221,42 +295,112 @@ 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; } @@ -264,23 +408,34 @@ 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 +445,36 @@ 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 +485,42 @@ 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 +528,9 @@ 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(); } /** @@ -378,37 +541,28 @@ 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: 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 ) @@ -418,158 +572,375 @@ 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 ); + + switch(Thread->Status) + { + case THREAD_STAT_PREINIT: // Only on main list + break; - giNumActiveThreads --; - giTotalTickets -= Thread->NumTickets; + // 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 ; + + default: + Log_Warning("Threads", "Threads_Kill - BUG Un-checked status (%i)", + Thread->Status); + break; + } - // 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, 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(isCurThread) + { + for( ;; ) + Proc_Reschedule(); + } } /** - * \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(); +// Log("Threads_Yield: by %p", __builtin_return_address(0)); + Proc_Reschedule(); } /** - * \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_Log("Threads", "%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 ); - - while(cur->Status != THREAD_STAT_ACTIVE) HALT(); + SHORTREL( &glThreadListLock ); + + 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 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: - //Log_Log("Threads", "Waking %i (%p) from sleeping", Thread->TID, Thread); - 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; - giNumActiveThreads ++; - giTotalTickets += Thread->NumTickets; - 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_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; + } + + SHORTLOCK( &glThreadListLock ); + Threads_AddActive( Thread ); + SHORTREL( &glThreadListLock ); + + #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"); - 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; } } -void Threads_WakeTID(tTID 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; +} + +void Threads_ToggleTrace(int TID) { - Threads_Wake( Threads_GetThread(Thread) ); + 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) { - LOCK( &giThreadListLock ); - Thread->Next = gActiveThreads; - gActiveThreads = Thread; + SHORTLOCK( &glThreadListLock ); + + 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 ++; - giTotalTickets += Thread->NumTickets; - //Log("Threads_AddActive: giNumActiveThreads = %i, giTotalTickets = %i", - // giNumActiveThreads, giTotalTickets); - RELEASE( &giThreadListLock ); + + #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_SetSignalHandler(Uint Handler) + * \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; } @@ -581,8 +952,6 @@ 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); @@ -601,27 +970,44 @@ 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(); } + thread->CurFaultNum = 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() +tPID Threads_GetPID(void) { return Proc_GetCurThread()->TGID; } -tTID Threads_GetTID() +tTID Threads_GetTID(void) { return Proc_GetCurThread()->TID; } -tUID Threads_GetUID() +tUID Threads_GetUID(void) { return Proc_GetCurThread()->UID; } -tGID Threads_GetGID() +tGID Threads_GetGID(void) { return Proc_GetCurThread()->GID; } @@ -633,7 +1019,7 @@ 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; } @@ -645,102 +1031,663 @@ 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() - * \brief Dums a list of currently running threads + * \fn void Threads_Dump(void) */ -void Threads_Dump() +void Threads_DumpActive(void) { tThread *thread; - tThread *cur = Proc_GetCurThread(); + #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("%c%i (%i) - %s", - (thread==cur?'*':' '), - 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( 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("%c%i (%i) - %s", - (thread==cur?'*':' '), - 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) * \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 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 + // DEFINITELY - free() can deadlock in this case + // I'll do it when it becomes an issue + 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; + } + + // 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) { - //Log_Debug("Threads", "CPU%i has no threads to run", CPU); + SHORTREL( &glThreadListLock ); + #if DEBUG_TRACE_TICKETS + Log("No active threads"); + #endif return NULL; } + #if SCHEDULER_TYPE != SCHED_RR_PRI // Special case: 1 thread if(giNumActiveThreads == 1) { - //Log_Debug("Threads", "CPU%i has only one thread %i %s", - // CPU, gActiveThreads->TID, gActiveThreads->ThreadName); - return gActiveThreads; + if( gActiveThreads->CurCPU == -1 ) + gActiveThreads->CurCPU = CPU; + + SHORTREL( &glThreadListLock ); + + if( gActiveThreads->CurCPU == CPU ) + return gActiveThreads; + + return NULL; // CPU has nothing to do } + #endif - //Log(" Threads_GetNextToRun: giNumActiveThreads=%i,giTotalTickets=%i", - // giNumActiveThreads, giTotalTickets); - // Get the ticket number - ticket = number = rand() % giTotalTickets; - - //Log(" Threads_GetNextToRun: ticket = %i", ticket); - - // 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("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 SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS + else + 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; } - // 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); + } + + 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 + } + + // --- + // 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( 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); + } + } + #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 - //Log_Debug("Threads", "Switching CPU%i to %p (%s)", - // CPU, thread, thread->ThreadName); + // Make the new thread non-schedulable + thread->CurCPU = CPU; + 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) +// Acquire mutex (see mutex.h for documentation) +int Mutex_Acquire(tMutex *Mutex) { - Warning("Thread #%i committed a segfault at address %p", Proc_GetCurThread()->TID, Addr); - Threads_Fault( 1 ); - //Threads_Exit( 0, -1 ); + 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 DEBUG_TRACE_STATE + Log("%p (%i %s) waiting on mutex %p", + us, us->TID, us->ThreadName, Mutex); + #endif + + #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; +} + +// Release a mutex +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 +} + +// Check if a mutex is locked +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) +{ + memset(Sem, 0, sizeof(tSemaphore)); + Sem->Value = Value; + Sem->ModName = Module; + Sem->Name = Name; + Sem->MaxValue = MaxValue; +} +// +// Wait for items to be avaliable +// +int Semaphore_Wait(tSemaphore *Sem, int MaxToTake) +{ + tThread *us; + int taken; + if( MaxToTake < 0 ) { + Log_Warning("Threads", "Semaphore_Wait: User bug - MaxToTake(%i) < 0, Sem=%p(%s)", + MaxToTake, Sem, Sem->Name); + } + + SHORTLOCK( &Sem->Protector ); + + // Check if there's already items avaliable + if( Sem->Value > 0 ) { + // Take what we need + if( MaxToTake && Sem->Value > MaxToTake ) + taken = MaxToTake; + else + taken = Sem->Value; + Sem->Value -= taken; + } + 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; + } + + #if DEBUG_TRACE_STATE || SEMAPHORE_DEBUG + Log("%p (%i %s) waiting on semaphore %p %s:%s", + us, us->TID, us->ThreadName, + Sem, Sem->ModName, Sem->Name); + #endif + + SHORTREL( &Sem->Protector ); // Release first to make sure it is released + SHORTREL( &glThreadListLock ); + while(us->Status == THREAD_STAT_SEMAPHORESLEEP) Threads_Yield(); + // We're only woken when there's something avaliable (or a signal arrives) + 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; + + + #if DEBUG_TRACE_STATE || SEMAPHORE_DEBUG + Log("%p (%i %s) woken by wait on %p %s:%s", + toWake, toWake->TID, toWake->ThreadName, + Sem, Sem->ModName, Sem->Name); + #endif + + // 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; + #if 0 + Log_Debug("Threads", "Semaphore_Signal: IDLE Sem = %s:%s", Sem->ModName, Sem->Name); + Log_Debug("Threads", "Semaphore_Signal: Sem->Value(%i) == Sem->MaxValue(%i)", Sem->Value, Sem->MaxValue); + #endif + + 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; + } + + #if DEBUG_TRACE_STATE || SEMAPHORE_DEBUG + Log("%p (%i %s) signaling semaphore %p %s:%s", + us, us->TID, us->ThreadName, + Sem, Sem->ModName, Sem->Name); + #endif + + 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; + + // Remove thread from list (double ended, so clear LastWaiting if needed) + Sem->Waiting = Sem->Waiting->Next; + if( Sem->Waiting == NULL ) + Sem->LastWaiting = NULL; + + // Figure out how much to give to woken thread + // - Requested count is stored in ->RetStatus + 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; + + if(toWake->bInstrTrace) + Log("%s(%i) given %i from %p", toWake->ThreadName, toWake->TID, given, Sem); + #if DEBUG_TRACE_STATE || SEMAPHORE_DEBUG + Log("%p (%i %s) woken by signal on %p %s:%s", + toWake, toWake->TID, toWake->ThreadName, + Sem, Sem->ModName, Sem->Name); + #endif + + // Wake the sleeper + SHORTLOCK( &glThreadListLock ); + if( toWake->Status != THREAD_STAT_ACTIVE ) + Threads_AddActive(toWake); + else + Warning("Thread %p (%i %s) is already awake", toWake, toWake->TID, toWake->ThreadName); + SHORTREL( &glThreadListLock ); + } + SHORTREL( &Sem->Protector ); + + return added; +} + +// +// Get the current value of a semaphore +// +int Semaphore_GetValue(tSemaphore *Sem) +{ + return Sem->Value; } // === EXPORTS === EXPORT(Threads_GetUID); +EXPORT(Threads_GetGID); +EXPORT(Mutex_Acquire); +EXPORT(Mutex_Release); +EXPORT(Mutex_IsLocked); +EXPORT(Semaphore_Init); +EXPORT(Semaphore_Wait); +EXPORT(Semaphore_Signal);