Kernel/threads.c

   1 /*
   2  * Acess2
   3  * threads.c
   4  * - Common Thread Control
   5  */
   6 #include <acess.h>
   7 #include <threads.h>
   8 #include <threads_int.h>
   9 #include <errno.h>
  10 #include <semaphore.h>
  11
  12 // Configuration
  13 #define DEBUG_TRACE_TICKETS     0       // Trace ticket counts
  14 #define DEBUG_TRACE_STATE       0       // Trace state changes (sleep/wake)
  15
  16 // --- Schedulers ---
  17 #define SCHED_UNDEF     0
  18 #define SCHED_LOTTERY   1       // Lottery scheduler
  19 #define SCHED_RR_SIM    2       // Single Queue Round Robin
  20 #define SCHED_RR_PRI    3       // Multi Queue Round Robin
  21 // Set scheduler type
  22 #define SCHEDULER_TYPE  SCHED_LOTTERY
  23
  24 // === CONSTANTS ===
  25 #define DEFAULT_QUANTUM 10
  26 #define DEFAULT_PRIORITY        5
  27 #define MIN_PRIORITY            10
  28 const enum eConfigTypes cCONFIG_TYPES[] = {
  29         CFGT_HEAPSTR,   // e.g. CFG_VFS_CWD
  30         CFGT_INT,       // e.g. CFG_VFS_MAXFILES
  31         CFGT_NULL
  32 };
  33
  34 // === IMPORTS ===
  35 extern void     ArchThreads_Init(void);
  36 extern void     Proc_CallFaultHandler(tThread *Thread);
  37 extern void     Proc_DumpThreadCPUState(tThread *Thread);
  38 extern int      GetCPUNum(void);
  39
  40 // === PROTOTYPES ===
  41 void    Threads_Init(void);
  42 #if 0
  43  int    Threads_SetName(const char *NewName);
  44 #endif
  45 char    *Threads_GetName(int ID);
  46 #if 0
  47 void    Threads_SetPriority(tThread *Thread, int Pri);
  48 tThread *Threads_CloneTCB(Uint *Err, Uint Flags);
  49  int    Threads_WaitTID(int TID, int *status);
  50 tThread *Threads_GetThread(Uint TID);
  51 #endif
  52 void    Threads_AddToDelete(tThread *Thread);
  53 tThread *Threads_int_DelFromQueue(tThread **List, tThread *Thread);
  54 #if 0
  55 void    Threads_Exit(int TID, int Status);
  56 void    Threads_Kill(tThread *Thread, int Status);
  57 void    Threads_Yield(void);
  58 void    Threads_Sleep(void);
  59  int    Threads_Wake(tThread *Thread);
  60 void    Threads_AddActive(tThread *Thread);
  61 tThread *Threads_RemActive(void);
  62 #endif
  63 void    Threads_ToggleTrace(int TID);
  64 void    Threads_Fault(int Num);
  65 void    Threads_SegFault(tVAddr Addr);
  66 #if 0
  67  int    Threads_GetPID(void);
  68  int    Threads_GetTID(void);
  69 tUID    Threads_GetUID(void);
  70 tGID    Threads_GetGID(void);
  71  int    Threads_SetUID(Uint *Errno, tUID ID);
  72  int    Threads_SetGID(Uint *Errno, tUID ID);
  73 #endif
  74 void    Threads_Dump(void);
  75 void    Threads_DumpActive(void);
  76 #if 0
  77  int    Mutex_Acquire(tMutex *Mutex);
  78 void    Mutex_Release(tMutex *Mutex);
  79  int    Mutex_IsLocked(tMutex *Mutex);
  80 #endif
  81
  82 // === GLOBALS ===
  83 // -- Core Thread --
  84 // Only used for the core kernel
  85 tThread gThreadZero = {
  86         .Status         = THREAD_STAT_ACTIVE,   // Status
  87         .ThreadName     = (char*)"ThreadZero",  // Name
  88         .Quantum        = DEFAULT_QUANTUM,      // Default Quantum
  89         .Remaining      = DEFAULT_QUANTUM,      // Current Quantum
  90         .Priority       = DEFAULT_PRIORITY      // Number of tickets
  91         };
  92 // -- Processes --
  93 // --- Locks ---
  94 tShortSpinlock  glThreadListLock;       ///\note NEVER use a heap function while locked
  95 // --- Current State ---
  96 volatile int    giNumActiveThreads = 0; // Number of threads on the active queue
  97 volatile Uint   giNextTID = 1;  // Next TID to allocate
  98 // --- Thread Lists ---
  99 tThread *gAllThreads = NULL;            // All allocated threads
 100 tThread *gSleepingThreads = NULL;       // Sleeping Threads
 101 tThread *gDeleteThreads = NULL;         // Threads to delete
 102  int    giNumCPUs = 1;  // Number of CPUs
 103 BOOL     gaThreads_NoTaskSwitch[MAX_CPUS];      // Disables task switches for each core (Pseudo-IF)
 104 // --- Scheduler Types ---
 105 #if SCHEDULER_TYPE == SCHED_LOTTERY
 106 const int       caiTICKET_COUNTS[MIN_PRIORITY+1] = {100,81,64,49,36,25,16,9,4,1,0};
 107 volatile int    giFreeTickets = 0;      // Number of tickets held by non-scheduled threads
 108 tThread *gActiveThreads = NULL;         // Currently Running Threads
 109 #elif SCHEDULER_TYPE == SCHED_RR_SIM
 110 tThread *gActiveThreads = NULL;         // Currently Running Threads
 111 #elif SCHEDULER_TYPE == SCHED_RR_PRI
 112 tThread *gaActiveThreads[MIN_PRIORITY+1];       // Active threads for each priority level
 113 #else
 114 # error "Unkown scheduler type"
 115 #endif
 116
 117 // === CODE ===
 118 /**
 119  * \fn void Threads_Init(void)
 120  * \brief Initialse the thread list
 121  */
 122 void Threads_Init(void)
 123 {
 124         ArchThreads_Init();
 125
 126         Log_Debug("Threads", "Offsets of tThread");
 127         Log_Debug("Threads", ".Priority = %i", offsetof(tThread, Priority));
 128
 129         // Create Initial Task
 130         #if SCHEDULER_TYPE == SCHED_RR_PRI
 131         gaActiveThreads[gThreadZero.Priority] = &gThreadZero;
 132         #else
 133         gActiveThreads = &gThreadZero;
 134         #endif
 135
 136         gAllThreads = &gThreadZero;
 137         giNumActiveThreads = 1;
 138
 139         Proc_Start();
 140 }
 141
 142 /**
 143  * \fn void Threads_SetName(const char *NewName)
 144  * \brief Sets the current thread's name
 145  * \param NewName       New name for the thread
 146  * \return Boolean Failure
 147  */
 148 int Threads_SetName(const char *NewName)
 149 {
 150         tThread *cur = Proc_GetCurThread();
 151         char    *oldname = cur->ThreadName;
 152
 153         // NOTE: There is a possibility of non-thread safety here
 154         // A thread could read the current name pointer before it is zeroed
 155
 156         cur->ThreadName = NULL;
 157
 158         if( IsHeap(oldname) )   free( oldname );
 159
 160         cur->ThreadName = strdup(NewName);
 161         return 0;
 162 }
 163
 164 /**
 165  * \fn char *Threads_GetName(int ID)
 166  * \brief Gets a thread's name
 167  * \param ID    Thread ID (-1 indicates current thread)
 168  * \return Pointer to name
 169  * \retval NULL Failure
 170  */
 171 char *Threads_GetName(tTID ID)
 172 {
 173         if(ID == -1) {
 174                 return Proc_GetCurThread()->ThreadName;
 175         }
 176         return Threads_GetThread(ID)->ThreadName;
 177 }
 178
 179 /**
 180  * \fn void Threads_SetPriority(tThread *Thread, int Pri)
 181  * \brief Sets the priority of a task
 182  * \param Thread        Thread to update ticket count (NULL means current thread)
 183  * \param Pri   New priority
 184  */
 185 void Threads_SetPriority(tThread *Thread, int Pri)
 186 {
 187         // Get current thread
 188         if(Thread == NULL)      Thread = Proc_GetCurThread();
 189         // Bounds checking
 190         // - If < 0, set to lowest priority
 191         // - Minumum priority is actualy a high number, 0 is highest
 192         if(Pri < 0)     Pri = MIN_PRIORITY;
 193         if(Pri > MIN_PRIORITY)  Pri = MIN_PRIORITY;
 194
 195         // Do we actually have to do anything?
 196         if( Pri == Thread->Priority )   return;
 197
 198         #if SCHEDULER_TYPE == SCHED_RR_PRI
 199         SHORTLOCK( &glThreadListLock );
 200         // Remove from old priority
 201         Threads_int_DelFromQueue( &gaActiveThreads[Thread->Priority], Thread );
 202         // And add to new
 203         Thread->Next = gaActiveThreads[Pri];
 204         gaActiveThreads[Pri] = Thread;
 205         Thread->Priority = Pri;
 206         SHORTREL( &glThreadListLock );
 207         #else
 208         // If this isn't the current thread, we need to lock
 209         if( Thread != Proc_GetCurThread() )
 210         {
 211                 SHORTLOCK( &glThreadListLock );
 212
 213                 #if SCHEDULER_TYPE == SCHED_LOTTERY
 214                 giFreeTickets -= caiTICKET_COUNTS[Thread->Priority] - caiTICKET_COUNTS[Pri];
 215                 # if DEBUG_TRACE_TICKETS
 216                 Log("Threads_SetTickets: new giFreeTickets = %i [-%i+%i]",
 217                         giFreeTickets,
 218                         caiTICKET_COUNTS[Thread->Priority], caiTICKET_COUNTS[Pri]);
 219                 # endif
 220                 #endif
 221                 Thread->Priority = Pri;
 222                 SHORTREL( &glThreadListLock );
 223         }
 224         else
 225                 Thread->Priority = Pri;
 226         #endif
 227
 228         #if DEBUG_TRACE_STATE
 229         Log("Threads_SetPriority: %p(%i %s) pri set %i",
 230                 Thread, Thread->TID, Thread->ThreadName,
 231                 Pri);
 232         #endif
 233 }
 234
 235 /**
 236  * \fn tThread *Threads_CloneTCB(Uint *Err, Uint Flags)
 237  * \brief Clone the TCB of the current thread
 238  * \param Err   Error pointer
 239  * \param Flags Flags for something... (What is this for?)
 240  */
 241 tThread *Threads_CloneTCB(Uint *Err, Uint Flags)
 242 {
 243         tThread *cur, *new;
 244          int    i;
 245         cur = Proc_GetCurThread();
 246
 247         // Allocate and duplicate
 248         new = malloc(sizeof(tThread));
 249         if(new == NULL) { *Err = -ENOMEM; return NULL; }
 250         memcpy(new, cur, sizeof(tThread));
 251
 252         new->CurCPU = -1;
 253         new->Next = NULL;
 254         memset( &new->IsLocked, 0, sizeof(new->IsLocked));
 255         new->Status = THREAD_STAT_PREINIT;
 256         new->RetStatus = 0;
 257
 258         // Get Thread ID
 259         new->TID = giNextTID++;
 260         new->Parent = cur;
 261         new->bInstrTrace = 0;
 262
 263         // Clone Name
 264         new->ThreadName = strdup(cur->ThreadName);
 265
 266         // Set Thread Group ID (PID)
 267         if(Flags & CLONE_VM)
 268                 new->TGID = new->TID;
 269         else
 270                 new->TGID = cur->TGID;
 271
 272         // Messages are not inherited
 273         new->Messages = NULL;
 274         new->LastMessage = NULL;
 275
 276         // Set State
 277         new->Remaining = new->Quantum = cur->Quantum;
 278         new->Priority = cur->Priority;
 279
 280         // Set Signal Handlers
 281         new->CurFaultNum = 0;
 282         new->FaultHandler = cur->FaultHandler;
 283
 284         for( i = 0; i < NUM_CFG_ENTRIES; i ++ )
 285         {
 286                 switch(cCONFIG_TYPES[i])
 287                 {
 288                 default:
 289                         new->Config[i] = cur->Config[i];
 290                         break;
 291                 case CFGT_HEAPSTR:
 292                         if(cur->Config[i])
 293                                 new->Config[i] = (Uint) strdup( (void*)cur->Config[i] );
 294                         else
 295                                 new->Config[i] = 0;
 296                         break;
 297                 }
 298         }
 299
 300         // Maintain a global list of threads
 301         SHORTLOCK( &glThreadListLock );
 302         new->GlobalPrev = NULL; // Protect against bugs
 303         new->GlobalNext = gAllThreads;
 304         gAllThreads->GlobalPrev = new;
 305         gAllThreads = new;
 306         SHORTREL( &glThreadListLock );
 307
 308         return new;
 309 }
 310
 311 /**
 312  * \fn tThread *Threads_CloneTCB(Uint *Err, Uint Flags)
 313  * \brief Clone the TCB of the current thread
 314  */
 315 tThread *Threads_CloneThreadZero(void)
 316 {
 317         tThread *cur, *new;
 318          int    i;
 319         cur = Proc_GetCurThread();
 320
 321         // Allocate and duplicate
 322         new = malloc(sizeof(tThread));
 323         if(new == NULL) {
 324                 return NULL;
 325         }
 326         memcpy(new, &gThreadZero, sizeof(tThread));
 327
 328         new->CurCPU = -1;
 329         new->Next = NULL;
 330         memset( &new->IsLocked, 0, sizeof(new->IsLocked));
 331         new->Status = THREAD_STAT_PREINIT;
 332         new->RetStatus = 0;
 333
 334         // Get Thread ID
 335         new->TID = giNextTID++;
 336         new->Parent = 0;
 337
 338         // Clone Name
 339         new->ThreadName = NULL;
 340
 341         // Messages are not inherited
 342         new->Messages = NULL;
 343         new->LastMessage = NULL;
 344
 345         // Set State
 346         new->Remaining = new->Quantum = cur->Quantum;
 347         new->Priority = cur->Priority;
 348         new->bInstrTrace = 0;
 349
 350         // Set Signal Handlers
 351         new->CurFaultNum = 0;
 352         new->FaultHandler = cur->FaultHandler;
 353
 354         for( i = 0; i < NUM_CFG_ENTRIES; i ++ )
 355         {
 356                 switch(cCONFIG_TYPES[i])
 357                 {
 358                 default:
 359                         new->Config[i] = cur->Config[i];
 360                         break;
 361                 case CFGT_HEAPSTR:
 362                         if(cur->Config[i])
 363                                 new->Config[i] = (Uint) strdup( (void*)cur->Config[i] );
 364                         else
 365                                 new->Config[i] = 0;
 366                         break;
 367                 }
 368         }
 369
 370         // Maintain a global list of threads
 371         SHORTLOCK( &glThreadListLock );
 372         new->GlobalPrev = NULL; // Protect against bugs
 373         new->GlobalNext = gAllThreads;
 374         gAllThreads->GlobalPrev = new;
 375         gAllThreads = new;
 376         SHORTREL( &glThreadListLock );
 377
 378         return new;
 379 }
 380
 381 /**
 382  * \brief Get a configuration pointer from the Per-Thread data area
 383  * \param ID    Config slot ID
 384  * \return Pointer at ID
 385  */
 386 Uint *Threads_GetCfgPtr(int ID)
 387 {
 388         if(ID < 0 || ID >= NUM_CFG_ENTRIES) {
 389                 Warning("Threads_GetCfgPtr: Index %i is out of bounds", ID);
 390                 return NULL;
 391         }
 392
 393         return &Proc_GetCurThread()->Config[ID];
 394 }
 395
 396 /**
 397  * \brief Wait for a task to change state
 398  * \param TID   Thread ID to wait on (-1: Any child thread, 0: Any Child/Sibling, <-1: -PID)
 399  * \param Status        Thread return status
 400  * \return TID of child that changed state
 401  */
 402 tTID Threads_WaitTID(int TID, int *Status)
 403 {
 404         // Any Child
 405         if(TID == -1) {
 406                 Log_Error("Threads", "TODO: Threads_WaitTID(TID=-1) - Any Child");
 407                 return -1;
 408         }
 409
 410         // Any peer/child thread
 411         if(TID == 0) {
 412                 Log_Error("Threads", "TODO: Threads_WaitTID(TID=0) - Any Child/Sibling");
 413                 return -1;
 414         }
 415
 416         // TGID = abs(TID)
 417         if(TID < -1) {
 418                 Log_Error("Threads", "TODO: Threads_WaitTID(TID<0) - TGID");
 419                 return -1;
 420         }
 421
 422         // Specific Thread
 423         if(TID > 0) {
 424                 tThread *t = Threads_GetThread(TID);
 425                  int    initStatus = t->Status;
 426                 tTID    ret;
 427
 428                 // Wait for the thread to die!
 429                 if(initStatus != THREAD_STAT_ZOMBIE) {
 430                         // TODO: Handle child also being suspended if wanted
 431                         while(t->Status != THREAD_STAT_ZOMBIE) {
 432                                 Threads_Sleep();
 433                                 Log_Debug("Threads", "%i waiting for %i, t->Status = %i",
 434                                         Threads_GetTID(), t->TID, t->Status);
 435                         }
 436                 }
 437
 438                 // Set return status
 439                 Log_Debug("Threads", "%i waiting for %i, t->Status = %i",
 440                         Threads_GetTID(), t->TID, t->Status);
 441                 ret = t->TID;
 442                 switch(t->Status)
 443                 {
 444                 case THREAD_STAT_ZOMBIE:
 445                         // Kill the thread
 446                         t->Status = THREAD_STAT_DEAD;
 447                         // TODO: Child return value?
 448                         if(Status)      *Status = t->RetStatus;
 449                         // add to delete queue
 450                         Threads_AddToDelete( t );
 451                         break;
 452                 default:
 453                         if(Status)      *Status = -1;
 454                         break;
 455                 }
 456                 return ret;
 457         }
 458
 459         return -1;
 460 }
 461
 462 /**
 463  * \brief Gets a thread given its TID
 464  * \param TID   Thread ID
 465  * \return Thread pointer
 466  */
 467 tThread *Threads_GetThread(Uint TID)
 468 {
 469         tThread *thread;
 470
 471         // Search global list
 472         for(thread = gAllThreads;
 473                 thread;
 474                 thread = thread->GlobalNext)
 475         {
 476                 if(thread->TID == TID)
 477                         return thread;
 478         }
 479
 480         Log("Unable to find TID %i on main list\n", TID);
 481
 482         return NULL;
 483 }
 484
 485 /**
 486  * \brief Adds a thread to the delete queue
 487  * \param Thread        Thread to delete
 488  */
 489 void Threads_AddToDelete(tThread *Thread)
 490 {
 491         // Add to delete queue
 492         // TODO: Is locking needed?
 493         if(gDeleteThreads) {
 494                 Thread->Next = gDeleteThreads;
 495                 gDeleteThreads = Thread;
 496         } else {
 497                 Thread->Next = NULL;
 498                 gDeleteThreads = Thread;
 499         }
 500 }
 501
 502 /**
 503  * \brief Deletes an entry from a list
 504  * \param List  Pointer to the list head
 505  * \param Thread        Thread to find
 506  * \return \a Thread
 507  */
 508 tThread *Threads_int_DelFromQueue(tThread **List, tThread *Thread)
 509 {
 510         tThread *ret, *prev = NULL;
 511
 512         for(ret = *List;
 513                 ret && ret != Thread;
 514                 prev = ret, ret = ret->Next
 515                 );
 516
 517         // Is the thread on the list
 518         if(!ret) {
 519                 //LogF("%p(%s) is not on list %p\n", Thread, Thread->ThreadName, List);
 520                 return NULL;
 521         }
 522
 523         if( !prev ) {
 524                 *List = Thread->Next;
 525                 //LogF("%p(%s) removed from head of %p\n", Thread, Thread->ThreadName, List);
 526         }
 527         else {
 528                 prev->Next = Thread->Next;
 529                 //LogF("%p(%s) removed from %p (prev=%p)\n", Thread, Thread->ThreadName, List, prev);
 530         }
 531
 532         return Thread;
 533 }
 534
 535 /**
 536  * \brief Exit the current process (or another?)
 537  * \param TID   Thread ID to kill
 538  * \param Status        Exit status
 539  */
 540 void Threads_Exit(int TID, int Status)
 541 {
 542         if( TID == 0 )
 543                 Threads_Kill( Proc_GetCurThread(), (Uint)Status & 0xFF );
 544         else
 545                 Threads_Kill( Threads_GetThread(TID), (Uint)Status & 0xFF );
 546
 547         // Halt forever, just in case
 548         for(;;) HALT();
 549 }
 550
 551 /**
 552  * \fn void Threads_Kill(tThread *Thread, int Status)
 553  * \brief Kill a thread
 554  * \param Thread        Thread to kill
 555  * \param Status        Status code to return to the parent
 556  */
 557 void Threads_Kill(tThread *Thread, int Status)
 558 {
 559         tMsg    *msg;
 560          int    isCurThread = Thread == Proc_GetCurThread();
 561
 562         // TODO: Kill all children
 563         #if 1
 564         {
 565                 tThread *child;
 566                 // TODO: I should keep a .Parent pointer, and a .Children list
 567                 for(child = gAllThreads;
 568                         child;
 569                         child = child->GlobalNext)
 570                 {
 571                         if(child->Parent == Thread)
 572                                 Threads_Kill(child, -1);
 573                 }
 574         }
 575         #endif
 576
 577         ///\note Double lock is needed due to overlap of lock areas
 578
 579         // Lock thread (stop us recieving messages)
 580         SHORTLOCK( &Thread->IsLocked );
 581
 582         // Clear Message Queue
 583         while( Thread->Messages )
 584         {
 585                 msg = Thread->Messages->Next;
 586                 free( Thread->Messages );
 587                 Thread->Messages = msg;
 588         }
 589
 590         // Lock thread list
 591         SHORTLOCK( &glThreadListLock );
 592
 593         switch(Thread->Status)
 594         {
 595         case THREAD_STAT_PREINIT:       // Only on main list
 596                 break;
 597
 598         // Currently active thread
 599         case THREAD_STAT_ACTIVE:
 600                 #if SCHEDULER_TYPE == SCHED_RR_PRI
 601                 if( Threads_int_DelFromQueue( &gaActiveThreads[Thread->Priority], Thread ) )
 602                 #else
 603                 if( Threads_int_DelFromQueue( &gActiveThreads, Thread ) )
 604                 #endif
 605                 {
 606                         // Ensure that we are not rescheduled
 607                         Thread->Remaining = 0;  // Clear Remaining Quantum
 608                         Thread->Quantum = 0;    // Clear Quantum to indicate dead thread
 609
 610                         // Update bookkeeping
 611                         giNumActiveThreads --;
 612                         #if SCHEDULER_TYPE == SCHED_LOTTERY
 613                         if( Thread != Proc_GetCurThread() )
 614                                 giFreeTickets -= caiTICKET_COUNTS[ Thread->Priority ];
 615                         #endif
 616                 }
 617                 else
 618                 {
 619                         Log_Warning("Threads",
 620                                 "Threads_Kill - Thread %p(%i,%s) marked as active, but not on list",
 621                                 Thread, Thread->TID, Thread->ThreadName
 622                                 );
 623                 }
 624                 break;
 625         // Kill it while it sleeps!
 626         case THREAD_STAT_SLEEPING:
 627                 if( !Threads_int_DelFromQueue( &gSleepingThreads, Thread ) )
 628                 {
 629                         Log_Warning("Threads",
 630                                 "Threads_Kill - Thread %p(%i,%s) marked as sleeping, but not on list",
 631                                 Thread, Thread->TID, Thread->ThreadName
 632                                 );
 633                 }
 634                 break;
 635
 636         // Brains!... You cannot kill
 637         case THREAD_STAT_ZOMBIE:
 638                 Log_Warning("Threads", "Threads_Kill - Thread %p(%i,%s) is undead, you cannot kill it",
 639                         Thread, Thread->TID, Thread->ThreadName);
 640                 SHORTREL( &glThreadListLock );
 641                 SHORTREL( &Thread->IsLocked );
 642                 return ;
 643
 644         default:
 645                 Log_Warning("Threads", "Threads_Kill - BUG Un-checked status (%i)",
 646                         Thread->Status);
 647                 break;
 648         }
 649
 650         // Save exit status
 651         Thread->RetStatus = Status;
 652
 653         // Don't Zombie if we are being killed because our parent is
 654         if(Status == -1)
 655         {
 656                 Thread->Status = THREAD_STAT_DEAD;
 657                 Threads_AddToDelete( Thread );
 658         } else {
 659                 Thread->Status = THREAD_STAT_ZOMBIE;
 660                 // Wake parent
 661                 Threads_Wake( Thread->Parent );
 662         }
 663
 664         Log("Thread %i went *hurk* (%i)", Thread->TID, Status);
 665
 666         // Release spinlocks
 667         SHORTREL( &glThreadListLock );
 668         SHORTREL( &Thread->IsLocked );  // TODO: We may not actually be released...
 669
 670         // And, reschedule
 671         if(isCurThread) {
 672                 for( ;; )
 673                         HALT();
 674         }
 675 }
 676
 677 /**
 678  * \brief Yield remainder of the current thread's timeslice
 679  */
 680 void Threads_Yield(void)
 681 {
 682         tThread *thread = Proc_GetCurThread();
 683         thread->Remaining = 0;
 684         //while(thread->Remaining == 0)
 685                 HALT();
 686 }
 687
 688 /**
 689  * \fn void Threads_Sleep(void)
 690  * \brief Take the current process off the run queue
 691  */
 692 void Threads_Sleep(void)
 693 {
 694         tThread *cur = Proc_GetCurThread();
 695
 696         // Acquire Spinlock
 697         SHORTLOCK( &glThreadListLock );
 698
 699         // Don't sleep if there is a message waiting
 700         if( cur->Messages ) {
 701                 SHORTREL( &glThreadListLock );
 702                 return;
 703         }
 704
 705         // Remove us from running queue
 706         Threads_RemActive();
 707         // Mark thread as sleeping
 708         cur->Status = THREAD_STAT_SLEEPING;
 709
 710         // Add to Sleeping List (at the top)
 711         cur->Next = gSleepingThreads;
 712         gSleepingThreads = cur;
 713
 714
 715         #if DEBUG_TRACE_STATE
 716         Log("Threads_Sleep: %p (%i %s) sleeping", cur, cur->TID, cur->ThreadName);
 717         #endif
 718
 719         // Release Spinlock
 720         SHORTREL( &glThreadListLock );
 721
 722         while(cur->Status != THREAD_STAT_ACTIVE)        HALT();
 723 }
 724
 725
 726 /**
 727  * \fn int Threads_Wake( tThread *Thread )
 728  * \brief Wakes a sleeping/waiting thread up
 729  * \param Thread        Thread to wake
 730  * \return Boolean Failure (Returns ERRNO)
 731  * \warning This should ONLY be called with task switches disabled
 732  */
 733 int Threads_Wake(tThread *Thread)
 734 {
 735         if(!Thread)
 736                 return -EINVAL;
 737
 738         switch(Thread->Status)
 739         {
 740         case THREAD_STAT_ACTIVE:
 741                 Log("Threads_Wake - Waking awake thread (%i)", Thread->TID);
 742                 return -EALREADY;
 743
 744         case THREAD_STAT_SLEEPING:
 745                 SHORTLOCK( &glThreadListLock );
 746                 // Remove from sleeping queue
 747                 Threads_int_DelFromQueue(&gSleepingThreads, Thread);
 748
 749                 Threads_AddActive( Thread );
 750
 751                 #if DEBUG_TRACE_STATE
 752                 Log("Threads_Sleep: %p (%i %s) woken", Thread, Thread->TID, Thread->ThreadName);
 753                 #endif
 754                 SHORTREL( &glThreadListLock );
 755                 return -EOK;
 756
 757         case THREAD_STAT_WAITING:
 758                 Warning("Threads_Wake - Waiting threads are not currently supported");
 759                 return -ENOTIMPL;
 760
 761         case THREAD_STAT_DEAD:
 762                 Warning("Threads_Wake - Attempt to wake dead thread (%i)", Thread->TID);
 763                 return -ENOTIMPL;
 764
 765         default:
 766                 Warning("Threads_Wake - Unknown process status (%i)\n", Thread->Status);
 767                 return -EINTERNAL;
 768         }
 769 }
 770
 771 /**
 772  * \brief Wake a thread given the TID
 773  * \param TID   Thread ID to wake
 774  * \return Boolean Faulure (errno)
 775  */
 776 int Threads_WakeTID(tTID TID)
 777 {
 778         tThread *thread = Threads_GetThread(TID);
 779          int    ret;
 780         if(!thread)
 781                 return -ENOENT;
 782         ret = Threads_Wake( thread );
 783         //Log_Debug("Threads", "TID %i woke %i (%p)", Threads_GetTID(), TID, thread);
 784         return ret;
 785 }
 786
 787 void Threads_ToggleTrace(int TID)
 788 {
 789         tThread *thread = Threads_GetThread(TID);
 790         if(!thread)     return ;
 791         thread->bInstrTrace = !thread->bInstrTrace;
 792 }
 793
 794 /**
 795  * \brief Adds a thread to the active queue
 796  */
 797 void Threads_AddActive(tThread *Thread)
 798 {
 799         SHORTLOCK( &glThreadListLock );
 800
 801         if( Thread->Status == THREAD_STAT_ACTIVE ) {
 802                 tThread *cur = Proc_GetCurThread();
 803                 Warning("WTF, CPU%i %p (%i %s) is adding %p (%i %s) when it is active",
 804                         GetCPUNum(), cur, cur->TID, cur->ThreadName, Thread, Thread->TID, Thread->ThreadName);
 805                 SHORTREL( &glThreadListLock );
 806                 return ;
 807         }
 808
 809         // Set state
 810         Thread->Status = THREAD_STAT_ACTIVE;
 811         // Add to active list
 812         #if SCHEDULER_TYPE == SCHED_RR_PRI
 813         Thread->Next = gaActiveThreads[Thread->Priority];
 814         gaActiveThreads[Thread->Priority] = Thread;
 815         #else
 816         Thread->Next = gActiveThreads;
 817         gActiveThreads = Thread;
 818         #endif
 819
 820         // Update bookkeeping
 821         giNumActiveThreads ++;
 822
 823         #if SCHEDULER_TYPE == SCHED_LOTTERY
 824         {
 825                  int    delta;
 826                 // Only change the ticket count if the thread is un-scheduled
 827                 if(Thread->CurCPU != -1)
 828                         delta = 0;
 829                 else
 830                         delta = caiTICKET_COUNTS[ Thread->Priority ];
 831
 832                 giFreeTickets += delta;
 833                 # if DEBUG_TRACE_TICKETS
 834                 Log("CPU%i %p (%i %s) added, new giFreeTickets = %i [+%i]",
 835                         GetCPUNum(), Thread, Thread->TID, Thread->ThreadName,
 836                         giFreeTickets, delta
 837                         );
 838                 # endif
 839         }
 840         #endif
 841
 842         SHORTREL( &glThreadListLock );
 843 }
 844
 845 /**
 846  * \brief Removes the current thread from the active queue
 847  * \warning This should ONLY be called with task switches disabled
 848  * \return Current thread pointer
 849  */
 850 tThread *Threads_RemActive(void)
 851 {
 852         tThread *ret = Proc_GetCurThread();
 853
 854         SHORTLOCK( &glThreadListLock );
 855
 856         // Delete from active queue
 857         #if SCHEDULER_TYPE == SCHED_RR_PRI
 858         if( !Threads_int_DelFromQueue(&gaActiveThreads[ret->Priority], ret) )
 859         #else
 860         if( !Threads_int_DelFromQueue(&gActiveThreads, ret) )
 861         #endif
 862         {
 863                 SHORTREL( &glThreadListLock );
 864                 return NULL;
 865         }
 866
 867         ret->Next = NULL;
 868         ret->Remaining = 0;
 869
 870         giNumActiveThreads --;
 871         // no need to decrement tickets, scheduler did it for us
 872
 873         #if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS
 874         Log("CPU%i %p (%i %s) removed, giFreeTickets = %i [nc]",
 875                 GetCPUNum(), ret, ret->TID, ret->ThreadName, giFreeTickets);
 876         #endif
 877
 878         SHORTREL( &glThreadListLock );
 879
 880         return ret;
 881 }
 882
 883 /**
 884  * \fn void Threads_SetFaultHandler(Uint Handler)
 885  * \brief Sets the signal handler for a signal
 886  */
 887 void Threads_SetFaultHandler(Uint Handler)
 888 {
 889         //Log_Debug("Threads", "Threads_SetFaultHandler: Handler = %p", Handler);
 890         Proc_GetCurThread()->FaultHandler = Handler;
 891 }
 892
 893 /**
 894  * \fn void Threads_Fault(int Num)
 895  * \brief Calls a fault handler
 896  */
 897 void Threads_Fault(int Num)
 898 {
 899         tThread *thread = Proc_GetCurThread();
 900
 901         Log_Log("Threads", "Threads_Fault: thread = %p", thread);
 902
 903         if(!thread)     return ;
 904
 905         Log_Log("Threads", "Threads_Fault: thread->FaultHandler = %p", thread->FaultHandler);
 906
 907         switch(thread->FaultHandler)
 908         {
 909         case 0: // Panic?
 910                 Threads_Kill(thread, -1);
 911                 HALT();
 912                 return ;
 913         case 1: // Dump Core?
 914                 Threads_Kill(thread, -1);
 915                 HALT();
 916                 return ;
 917         }
 918
 919         // Double Fault? Oh, F**k
 920         if(thread->CurFaultNum != 0) {
 921                 Threads_Kill(thread, -1);       // For now, just kill
 922                 HALT();
 923         }
 924
 925         thread->CurFaultNum = Num;
 926
 927         Proc_CallFaultHandler(thread);
 928 }
 929
 930 /**
 931  * \fn void Threads_SegFault(tVAddr Addr)
 932  * \brief Called when a Segment Fault occurs
 933  */
 934 void Threads_SegFault(tVAddr Addr)
 935 {
 936         Warning("Thread #%i committed a segfault at address %p", Proc_GetCurThread()->TID, Addr);
 937         Threads_Fault( 1 );
 938         //Threads_Exit( 0, -1 );
 939 }
 940
 941 // --- Process Structure Access Functions ---
 942 tPID Threads_GetPID(void)
 943 {
 944         return Proc_GetCurThread()->TGID;
 945 }
 946 tTID Threads_GetTID(void)
 947 {
 948         return Proc_GetCurThread()->TID;
 949 }
 950 tUID Threads_GetUID(void)
 951 {
 952         return Proc_GetCurThread()->UID;
 953 }
 954 tGID Threads_GetGID(void)
 955 {
 956         return Proc_GetCurThread()->GID;
 957 }
 958
 959 int Threads_SetUID(Uint *Errno, tUID ID)
 960 {
 961         tThread *t = Proc_GetCurThread();
 962         if( t->UID != 0 ) {
 963                 *Errno = -EACCES;
 964                 return -1;
 965         }
 966         Log_Debug("Threads", "TID %i's UID set to %i", t->TID, ID);
 967         t->UID = ID;
 968         return 0;
 969 }
 970
 971 int Threads_SetGID(Uint *Errno, tGID ID)
 972 {
 973         tThread *t = Proc_GetCurThread();
 974         if( t->UID != 0 ) {
 975                 *Errno = -EACCES;
 976                 return -1;
 977         }
 978         Log_Debug("Threads", "TID %i's GID set to %i", t->TID, ID);
 979         t->GID = ID;
 980         return 0;
 981 }
 982
 983 /**
 984  * \fn void Threads_Dump(void)
 985  */
 986 void Threads_DumpActive(void)
 987 {
 988         tThread *thread;
 989         #if SCHEDULER_TYPE == SCHED_RR_PRI
 990          int    i;
 991         #endif
 992
 993         Log("Active Threads: (%i reported)", giNumActiveThreads);
 994
 995         #if SCHEDULER_TYPE == SCHED_RR_PRI
 996         for( i = 0; i < MIN_PRIORITY+1; i++ )
 997         {
 998                 for(thread=gaActiveThreads[i];thread;thread=thread->Next)
 999         #else
1000                 for(thread=gActiveThreads;thread;thread=thread->Next)
1001         #endif
1002                 {
1003                         Log(" %p %i (%i) - %s (CPU %i)",
1004                                 thread, thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
1005                         if(thread->Status != THREAD_STAT_ACTIVE)
1006                                 Log("  ERROR State (%i) != THREAD_STAT_ACTIVE (%i)", thread->Status, THREAD_STAT_ACTIVE);
1007                         Log("  Priority %i, Quantum %i", thread->Priority, thread->Quantum);
1008                         Log("  KStack 0x%x", thread->KernelStack);
1009                         if( thread->bInstrTrace )
1010                                 Log("  Tracing Enabled");
1011                         Proc_DumpThreadCPUState(thread);
1012                 }
1013
1014         #if SCHEDULER_TYPE == SCHED_RR_PRI
1015         }
1016         #endif
1017 }
1018
1019 /**
1020  * \fn void Threads_Dump(void)
1021  * \brief Dumps a list of currently running threads
1022  */
1023 void Threads_Dump(void)
1024 {
1025         tThread *thread;
1026
1027         Log("--- Thread Dump ---");
1028         Threads_DumpActive();
1029
1030         Log("All Threads:");
1031         for(thread=gAllThreads;thread;thread=thread->GlobalNext)
1032         {
1033                 Log(" %p %i (%i) - %s (CPU %i)",
1034                         thread, thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
1035                 Log("  State %i (%s)", thread->Status, casTHREAD_STAT[thread->Status]);
1036                 switch(thread->Status)
1037                 {
1038                 case THREAD_STAT_MUTEXSLEEP:
1039                         Log("  Mutex Pointer: %p", thread->WaitPointer);
1040                         break;
1041                 case THREAD_STAT_SEMAPHORESLEEP:
1042                         Log("  Semaphore Pointer: %p", thread->WaitPointer);
1043                         Log("  Semaphore Name: %s:%s",
1044                                 ((tSemaphore*)thread->WaitPointer)->ModName,
1045                                 ((tSemaphore*)thread->WaitPointer)->Name
1046                                 );
1047                         break;
1048                 case THREAD_STAT_ZOMBIE:
1049                         Log("  Return Status: %i", thread->RetStatus);
1050                         break;
1051                 default:        break;
1052                 }
1053                 Log("  Priority %i, Quantum %i", thread->Priority, thread->Quantum);
1054                 Log("  KStack 0x%x", thread->KernelStack);
1055                 if( thread->bInstrTrace )
1056                         Log("  Tracing Enabled");
1057                 Proc_DumpThreadCPUState(thread);
1058         }
1059 }
1060
1061 /**
1062  * \brief Gets the next thread to run
1063  * \param CPU   Current CPU
1064  * \param Last  The thread the CPU was running
1065  */
1066 tThread *Threads_GetNextToRun(int CPU, tThread *Last)
1067 {
1068         tThread *thread;
1069
1070         // If this CPU has the lock, we must let it complete
1071         if( CPU_HAS_LOCK( &glThreadListLock ) )
1072                 return Last;
1073
1074         // Don't change threads if the current CPU has switches disabled
1075         if( gaThreads_NoTaskSwitch[CPU] )
1076                 return Last;
1077
1078
1079         // Lock thread list
1080         SHORTLOCK( &glThreadListLock );
1081
1082         // Clear Delete Queue
1083         // - I should probably put this in a worker thread to avoid calling free() in the scheduler
1084         //   DEFINITELY - free() can deadlock in this case
1085         while(gDeleteThreads)
1086         {
1087                 thread = gDeleteThreads->Next;
1088                 // Only free if structure is unused
1089                 if( !IS_LOCKED(&gDeleteThreads->IsLocked) )
1090                 {
1091                         // Set to dead
1092                         gDeleteThreads->Status = THREAD_STAT_BURIED;
1093                         // Free name
1094                         if( IsHeap(gDeleteThreads->ThreadName) )
1095                                 free(gDeleteThreads->ThreadName);
1096                         // Remove from global list
1097                         if( gDeleteThreads == gAllThreads )
1098                                 gAllThreads = gDeleteThreads->GlobalNext;
1099                         else
1100                                 gDeleteThreads->GlobalPrev->GlobalNext = gDeleteThreads->GlobalNext;
1101                         free( gDeleteThreads );
1102                 }
1103                 gDeleteThreads = thread;
1104         }
1105
1106         // No active threads, just take a nap
1107         if(giNumActiveThreads == 0) {
1108                 SHORTREL( &glThreadListLock );
1109                 #if DEBUG_TRACE_TICKETS
1110                 Log("No active threads");
1111                 #endif
1112                 return NULL;
1113         }
1114
1115         #if SCHEDULER_TYPE != SCHED_RR_PRI
1116         // Special case: 1 thread
1117         if(giNumActiveThreads == 1) {
1118                 if( gActiveThreads->CurCPU == -1 )
1119                         gActiveThreads->CurCPU = CPU;
1120
1121                 SHORTREL( &glThreadListLock );
1122
1123                 if( gActiveThreads->CurCPU == CPU )
1124                         return gActiveThreads;
1125
1126                 return NULL;    // CPU has nothing to do
1127         }
1128         #endif
1129
1130         // Allow the old thread to be scheduled again
1131         if( Last ) {
1132                 if( Last->Status == THREAD_STAT_ACTIVE ) {
1133                         #if SCHEDULER_TYPE == SCHED_LOTTERY
1134                         giFreeTickets += caiTICKET_COUNTS[ Last->Priority ];
1135                         # if DEBUG_TRACE_TICKETS
1136                         LogF("Log: CPU%i released %p (%i %s) into the pool (%i [+%i] tickets in pool)\n",
1137                                 CPU, Last, Last->TID, Last->ThreadName, giFreeTickets,
1138                                 caiTICKET_COUNTS[ Last->Priority ]);
1139                         # endif
1140                         #endif
1141                 }
1142                 #if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS
1143                 else
1144                         LogF("Log: CPU%i released %p (%i %s)->Status = %i (Released,not in pool)\n",
1145                                 CPU, Last, Last->TID, Last->ThreadName, Last->Status);
1146                 #endif
1147                 Last->CurCPU = -1;
1148         }
1149
1150         // ---
1151         // Lottery Scheduler
1152         // ---
1153         #if SCHEDULER_TYPE == SCHED_LOTTERY
1154         {
1155                  int    ticket, number;
1156                 # if 1
1157                 number = 0;
1158                 for(thread = gActiveThreads; thread; thread = thread->Next) {
1159                         if(thread->CurCPU >= 0) continue;
1160                         if(thread->Status != THREAD_STAT_ACTIVE)
1161                                 Panic("Bookkeeping fail - %p %i(%s) is on the active queue with a status of %i",
1162                                         thread, thread->TID, thread->ThreadName, thread->Status);
1163                         if(thread->Next == thread) {
1164                                 Panic("Bookkeeping fail - %p %i(%s) loops back on itself",
1165                                         thread, thread->TID, thread->ThreadName, thread->Status);
1166                         }
1167                         number += caiTICKET_COUNTS[ thread->Priority ];
1168                 }
1169                 if(number != giFreeTickets) {
1170                         Panic("Bookkeeping fail (giFreeTickets(%i) != number(%i)) - CPU%i",
1171                                 giFreeTickets, number, CPU);
1172                 }
1173                 # endif
1174
1175                 // No free tickets (all tasks delegated to cores)
1176                 if( giFreeTickets == 0 ) {
1177                         SHORTREL(&glThreadListLock);
1178                         return NULL;
1179                 }
1180
1181                 // Get the ticket number
1182                 ticket = number = rand() % giFreeTickets;
1183
1184                 // Find the next thread
1185                 for(thread=gActiveThreads;thread;thread=thread->Next)
1186                 {
1187                         if(thread->CurCPU >= 0) continue;
1188                         if( caiTICKET_COUNTS[ thread->Priority ] > number)      break;
1189                         number -= caiTICKET_COUNTS[ thread->Priority ];
1190                 }
1191
1192                 // If we didn't find a thread, something went wrong
1193                 if(thread == NULL)
1194                 {
1195                         number = 0;
1196                         for(thread=gActiveThreads;thread;thread=thread->Next) {
1197                                 if(thread->CurCPU >= 0) continue;
1198                                 number += caiTICKET_COUNTS[ thread->Priority ];
1199                         }
1200                         Panic("Bookeeping Failed - giFreeTickets(%i) > true count (%i)",
1201                                 giFreeTickets, number);
1202                 }
1203
1204                 giFreeTickets -= caiTICKET_COUNTS[ thread->Priority ];
1205                 # if DEBUG_TRACE_TICKETS
1206                 LogF("Log: CPU%i allocated %p (%i %s), (%i [-%i] tickets in pool), \n",
1207                         CPU, thread, thread->TID, thread->ThreadName,
1208                         giFreeTickets, caiTICKET_COUNTS[ thread->Priority ]);
1209                 # endif
1210         }
1211
1212         // ---
1213         // Priority based round robin scheduler
1214         // ---
1215         #elif SCHEDULER_TYPE == SCHED_RR_PRI
1216         {
1217                  int    i;
1218                 for( i = 0; i < MIN_PRIORITY + 1; i ++ )
1219                 {
1220                         for(thread = gaActiveThreads[i]; thread; thread = thread->Next)
1221                         {
1222                                 if( thread->CurCPU == -1 )      break;
1223                         }
1224                         // If we fall onto the same queue again, special handling is
1225                         // needed
1226                         if( i == Last->Priority ) {
1227                                 tThread *savedThread = thread;
1228
1229                                 // Find the next unscheduled thread in the list
1230                                 for( thread = Last->Next; thread; thread = thread->Next )
1231                                 {
1232                                         if( thread->CurCPU == -1 )      break;
1233                                 }
1234                                 // If we don't find anything after, just use the one
1235                                 // found above.
1236                                 if( !thread )   thread = savedThread;
1237                         }
1238                         // Found a thread? Schedule it!
1239                         if( thread )    break;
1240                 }
1241
1242                 // Anything to do?
1243                 if( !thread ) {
1244                         SHORTREL(&glThreadListLock);
1245                         return NULL;
1246                 }
1247         }
1248         #elif SCHEDULER_TYPE == SCHED_RR_SIM
1249         {
1250                 // Find the next unscheduled thread in the list
1251                 for( thread = Last->Next; thread; thread = thread->Next )
1252                 {
1253                         if( thread->CurCPU == -1 )      break;
1254                 }
1255                 // If we don't find anything after, search from the beginning
1256                 if( !thread )
1257                 {
1258                         for(thread = gActiveThreads; thread; thread = thread->Next)
1259                         {
1260                                 if( thread->CurCPU == -1 )      break;
1261                         }
1262                 }
1263
1264                 // Anything to do?
1265                 if( !thread ) {
1266                         SHORTREL(&glThreadListLock);
1267                         return NULL;
1268                 }
1269         }
1270         #else
1271         # error "Unimplemented scheduling algorithm"
1272         #endif
1273
1274         // Make the new thread non-schedulable
1275         thread->CurCPU = CPU;
1276
1277         SHORTREL( &glThreadListLock );
1278
1279         return thread;
1280 }
1281
1282 // Acquire mutex (see mutex.h for documentation)
1283 int Mutex_Acquire(tMutex *Mutex)
1284 {
1285         tThread *us = Proc_GetCurThread();
1286
1287         // Get protector
1288         SHORTLOCK( &Mutex->Protector );
1289
1290         //Log("Mutex_Acquire: (%p)", Mutex);
1291
1292         // Check if the lock is already held
1293         if( Mutex->Owner ) {
1294                 SHORTLOCK( &glThreadListLock );
1295                 // - Remove from active list
1296                 us = Threads_RemActive();
1297                 us->Next = NULL;
1298                 // - Mark as sleeping
1299                 us->Status = THREAD_STAT_MUTEXSLEEP;
1300                 us->WaitPointer = Mutex;
1301
1302                 // - Add to waiting
1303                 if(Mutex->LastWaiting) {
1304                         Mutex->LastWaiting->Next = us;
1305                         Mutex->LastWaiting = us;
1306                 }
1307                 else {
1308                         Mutex->Waiting = us;
1309                         Mutex->LastWaiting = us;
1310                 }
1311
1312                 #if DEBUG_TRACE_STATE
1313                 Log("%p (%i %s) waiting on mutex %p",
1314                         us, us->TID, us->ThreadName, Mutex);
1315                 #endif
1316
1317                 #if 0
1318                 {
1319                          int    i = 0;
1320                         tThread *t;
1321                         for( t = Mutex->Waiting; t; t = t->Next, i++ )
1322                                 Log("[%i] (tMutex)%p->Waiting[%i] = %p (%i %s)", us->TID, Mutex, i,
1323                                         t, t->TID, t->ThreadName);
1324                 }
1325                 #endif
1326
1327                 SHORTREL( &glThreadListLock );
1328                 SHORTREL( &Mutex->Protector );
1329                 while(us->Status == THREAD_STAT_MUTEXSLEEP)     Threads_Yield();
1330                 // We're only woken when we get the lock
1331                 us->WaitPointer = NULL;
1332         }
1333         // Ooh, let's take it!
1334         else {
1335                 Mutex->Owner = us;
1336                 SHORTREL( &Mutex->Protector );
1337         }
1338
1339         #if 0
1340         extern tMutex   glPhysAlloc;
1341         if( Mutex != &glPhysAlloc )
1342                 LogF("Mutex %p taken by %i %p\n", Mutex, us->TID, __builtin_return_address(0));
1343         #endif
1344
1345         return 0;
1346 }
1347
1348 // Release a mutex
1349 void Mutex_Release(tMutex *Mutex)
1350 {
1351         SHORTLOCK( &Mutex->Protector );
1352         //Log("Mutex_Release: (%p)", Mutex);
1353         if( Mutex->Waiting ) {
1354                 Mutex->Owner = Mutex->Waiting;  // Set owner
1355                 Mutex->Waiting = Mutex->Waiting->Next;  // Next!
1356                 // Reset ->LastWaiting to NULL if we have just removed the last waiting thread
1357                 // 2010-10-02 21:50 - Comemerating the death of the longest single
1358                 //                    blocker in the Acess2 history. REMEMBER TO
1359                 //                    FUCKING MAINTAIN YOUR FUCKING LISTS DIPWIT
1360                 if( Mutex->LastWaiting == Mutex->Owner )
1361                         Mutex->LastWaiting = NULL;
1362
1363                 // Wake new owner
1364                 SHORTLOCK( &glThreadListLock );
1365                 if( Mutex->Owner->Status != THREAD_STAT_ACTIVE )
1366                         Threads_AddActive(Mutex->Owner);
1367                 SHORTREL( &glThreadListLock );
1368         }
1369         else {
1370                 Mutex->Owner = NULL;
1371         }
1372         SHORTREL( &Mutex->Protector );
1373
1374         #if 0
1375         extern tMutex   glPhysAlloc;
1376         if( Mutex != &glPhysAlloc )
1377                 LogF("Mutex %p released by %i %p\n", Mutex, Threads_GetTID(), __builtin_return_address(0));
1378         #endif
1379 }
1380
1381 // Check if a mutex is locked
1382 int Mutex_IsLocked(tMutex *Mutex)
1383 {
1384         return Mutex->Owner != NULL;
1385 }
1386
1387 //
1388 // Initialise a semaphore
1389 //
1390 void Semaphore_Init(tSemaphore *Sem, int Value, int MaxValue, const char *Module, const char *Name)
1391 {
1392         memset(Sem, 0, sizeof(tSemaphore));
1393         Sem->Value = Value;
1394         Sem->ModName = Module;
1395         Sem->Name = Name;
1396         Sem->MaxValue = MaxValue;
1397 }
1398 //
1399 // Wait for items to be avaliable
1400 //
1401 int Semaphore_Wait(tSemaphore *Sem, int MaxToTake)
1402 {
1403         tThread *us;
1404          int    taken;
1405         if( MaxToTake < 0 ) {
1406                 Log_Warning("Threads", "Semaphore_Wait: User bug - MaxToTake(%i) < 0, Sem=%p(%s)",
1407                         MaxToTake, Sem, Sem->Name);
1408         }
1409
1410         SHORTLOCK( &Sem->Protector );
1411
1412         // Check if there's already items avaliable
1413         if( Sem->Value > 0 ) {
1414                 // Take what we need
1415                 if( MaxToTake && Sem->Value > MaxToTake )
1416                         taken = MaxToTake;
1417                 else
1418                         taken = Sem->Value;
1419                 Sem->Value -= taken;
1420                 SHORTREL( &Sem->Protector );
1421         }
1422         else
1423         {
1424                 SHORTLOCK( &glThreadListLock );
1425
1426                 // - Remove from active list
1427                 us = Threads_RemActive();
1428                 us->Next = NULL;
1429                 // - Mark as sleeping
1430                 us->Status = THREAD_STAT_SEMAPHORESLEEP;
1431                 us->WaitPointer = Sem;
1432                 us->RetStatus = MaxToTake;      // Use RetStatus as a temp variable
1433
1434                 // - Add to waiting
1435                 if(Sem->LastWaiting) {
1436                         Sem->LastWaiting->Next = us;
1437                         Sem->LastWaiting = us;
1438                 }
1439                 else {
1440                         Sem->Waiting = us;
1441                         Sem->LastWaiting = us;
1442                 }
1443
1444                 #if DEBUG_TRACE_STATE
1445                 Log("%p (%i %s) waiting on semaphore %p %s:%s",
1446                         us, us->TID, us->ThreadName,
1447                         Sem, Sem->ModName, Sem->Name);
1448                 #endif
1449
1450                 SHORTREL( &glThreadListLock );
1451                 SHORTREL( &Sem->Protector );
1452                 while(us->Status == THREAD_STAT_SEMAPHORESLEEP) Threads_Yield();
1453                 // We're only woken when there's something avaliable
1454                 us->WaitPointer = NULL;
1455
1456                 taken = us->RetStatus;
1457
1458                 // Get the lock again
1459                 SHORTLOCK( &Sem->Protector );
1460         }
1461
1462         // While there is space, and there are thread waiting
1463         // wake the first thread and give it what it wants (or what's left)
1464         while( (Sem->MaxValue == 0 || Sem->Value < Sem->MaxValue) && Sem->Signaling )
1465         {
1466                  int    given;
1467                 tThread *toWake = Sem->Signaling;
1468
1469                 Sem->Signaling = Sem->Signaling->Next;
1470                 // Reset ->LastWaiting to NULL if we have just removed the last waiting thread
1471                 if( Sem->Signaling == NULL )
1472                         Sem->LastSignaling = NULL;
1473
1474                 // Figure out how much to give
1475                 if( toWake->RetStatus && Sem->Value + toWake->RetStatus < Sem->MaxValue )
1476                         given = toWake->RetStatus;
1477                 else
1478                         given = Sem->MaxValue - Sem->Value;
1479                 Sem->Value -= given;
1480
1481
1482                 #if DEBUG_TRACE_STATE
1483                 Log("%p (%i %s) woken by wait on %p %s:%s",
1484                         toWake, toWake->TID, toWake->ThreadName,
1485                         Sem, Sem->ModName, Sem->Name);
1486                 #endif
1487
1488                 // Save the number we gave to the thread's status
1489                 toWake->RetStatus = given;
1490
1491                 // Wake the sleeper
1492                 SHORTLOCK( &glThreadListLock );
1493                 if( toWake->Status != THREAD_STAT_ACTIVE )
1494                         Threads_AddActive(toWake);
1495                 SHORTREL( &glThreadListLock );
1496         }
1497         SHORTREL( &Sem->Protector );
1498
1499         return taken;
1500 }
1501
1502 //
1503 // Add items to a semaphore
1504 //
1505 int Semaphore_Signal(tSemaphore *Sem, int AmmountToAdd)
1506 {
1507          int    given;
1508          int    added;
1509
1510         if( AmmountToAdd < 0 ) {
1511                 Log_Warning("Threads", "Semaphore_Signal: User bug - AmmountToAdd(%i) < 0, Sem=%p(%s)",
1512                         AmmountToAdd, Sem, Sem->Name);
1513         }
1514         SHORTLOCK( &Sem->Protector );
1515
1516         // Check if we have to block
1517         if( Sem->MaxValue && Sem->Value == Sem->MaxValue )
1518         {
1519                 tThread *us;
1520                 #if 0
1521                 Log_Debug("Threads", "Semaphore_Signal: IDLE Sem = %s:%s", Sem->ModName, Sem->Name);
1522                 Log_Debug("Threads", "Semaphore_Signal: Sem->Value(%i) == Sem->MaxValue(%i)", Sem->Value, Sem->MaxValue);
1523                 #endif
1524
1525                 SHORTLOCK( &glThreadListLock );
1526                 // - Remove from active list
1527                 us = Threads_RemActive();
1528                 us->Next = NULL;
1529                 // - Mark as sleeping
1530                 us->Status = THREAD_STAT_SEMAPHORESLEEP;
1531                 us->WaitPointer = Sem;
1532                 us->RetStatus = AmmountToAdd;   // Use RetStatus as a temp variable
1533
1534                 // - Add to waiting
1535                 if(Sem->LastSignaling) {
1536                         Sem->LastSignaling->Next = us;
1537                         Sem->LastSignaling = us;
1538                 }
1539                 else {
1540                         Sem->Signaling = us;
1541                         Sem->LastSignaling = us;
1542                 }
1543
1544                 #if DEBUG_TRACE_STATE
1545                 Log("%p (%i %s) signaling semaphore %p %s:%s",
1546                         us, us->TID, us->ThreadName,
1547                         Sem, Sem->ModName, Sem->Name);
1548                 #endif
1549
1550                 SHORTREL( &glThreadListLock );
1551                 SHORTREL( &Sem->Protector );
1552                 while(us->Status == THREAD_STAT_SEMAPHORESLEEP) Threads_Yield();
1553                 // We're only woken when there's something avaliable
1554                 us->WaitPointer = NULL;
1555
1556                 added = us->RetStatus;
1557
1558                 // Get the lock again
1559                 SHORTLOCK( &Sem->Protector );
1560         }
1561         // Non blocking
1562         else
1563         {
1564                 // Figure out how much we need to take off
1565                 if( Sem->MaxValue && Sem->Value + AmmountToAdd > Sem->MaxValue)
1566                         added = Sem->MaxValue - Sem->Value;
1567                 else
1568                         added = AmmountToAdd;
1569                 Sem->Value += added;
1570         }
1571
1572         // While there are items avaliable, and there are thread waiting
1573         // wake the first thread and give it what it wants (or what's left)
1574         while( Sem->Value && Sem->Waiting )
1575         {
1576                 tThread *toWake = Sem->Waiting;
1577
1578                 // Remove thread from list (double ended, so clear LastWaiting if needed)
1579                 Sem->Waiting = Sem->Waiting->Next;
1580                 if( Sem->Waiting == NULL )
1581                         Sem->LastWaiting = NULL;
1582
1583                 // Figure out how much to give to woken thread
1584                 // - Requested count is stored in ->RetStatus
1585                 if( toWake->RetStatus && Sem->Value > toWake->RetStatus )
1586                         given = toWake->RetStatus;
1587                 else
1588                         given = Sem->Value;
1589                 Sem->Value -= given;
1590
1591                 // Save the number we gave to the thread's status
1592                 toWake->RetStatus = given;
1593
1594                 if(toWake->bInstrTrace)
1595                         Log("%s(%i) given %i from %p", toWake->ThreadName, toWake->TID, given, Sem);
1596                 #if DEBUG_TRACE_STATE
1597                 Log("%p (%i %s) woken by signal on %p %s:%s",
1598                         toWake, toWake->TID, toWake->ThreadName,
1599                         Sem, Sem->ModName, Sem->Name);
1600                 #endif
1601
1602                 // Wake the sleeper
1603                 SHORTLOCK( &glThreadListLock );
1604                 if( toWake->Status != THREAD_STAT_ACTIVE )
1605                         Threads_AddActive(toWake);
1606                 SHORTREL( &glThreadListLock );
1607         }
1608         SHORTREL( &Sem->Protector );
1609
1610         return added;
1611 }
1612
1613 //
1614 // Get the current value of a semaphore
1615 //
1616 int Semaphore_GetValue(tSemaphore *Sem)
1617 {
1618         return Sem->Value;
1619 }
1620
1621 // === EXPORTS ===
1622 EXPORT(Threads_GetUID);
1623 EXPORT(Threads_GetGID);
1624 EXPORT(Mutex_Acquire);
1625 EXPORT(Mutex_Release);
1626 EXPORT(Mutex_IsLocked);
1627 EXPORT(Semaphore_Init);
1628 EXPORT(Semaphore_Wait);
1629 EXPORT(Semaphore_Signal);