ghc/rts/Schedule.h

   1 /* -----------------------------------------------------------------------------
   2  * $Id: Schedule.h,v 1.16 2000/03/16 17:27:13 simonmar Exp $
   3  *
   4  * (c) The GHC Team 1998-1999
   5  *
   6  * Prototypes for functions in Schedule.c
   7  * (RTS internal scheduler interface)
   8  *
   9  * -------------------------------------------------------------------------*/
  10
  11 //@menu
  12 //* Scheduler Functions::
  13 //* Scheduler Vars and Data Types::
  14 //* Some convenient macros::
  15 //* Index::
  16 //@end menu
  17
  18 //@node Scheduler Functions, Scheduler Vars and Data Types
  19 //@subsection Scheduler Functions
  20
  21 //@cindex initScheduler
  22 //@cindex exitScheduler
  23 //@cindex startTasks
  24 /* initScheduler(), exitScheduler(), startTasks()
  25  *
  26  * Called from STG :  no
  27  * Locks assumed   :  none
  28  */
  29 void initScheduler( void );
  30 void exitScheduler( void );
  31 #ifdef SMP
  32 void startTasks( void );
  33 #endif
  34
  35 //@cindex awakenBlockedQueue
  36 /* awakenBlockedQueue()
  37  *
  38  * Takes a pointer to the beginning of a blocked TSO queue, and
  39  * wakes up the entire queue.
  40  *
  41  * Called from STG :  yes
  42  * Locks assumed   :  none
  43  */
  44 #if defined(GRAN)
  45 void awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node);
  46 #elif defined(PAR)
  47 void awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node);
  48 #else
  49 void awakenBlockedQueue(StgTSO *tso);
  50 #endif
  51
  52 //@cindex unblockOne
  53 /* unblockOne()
  54  *
  55  * Takes a pointer to the beginning of a blocked TSO queue, and
  56  * removes the first thread, placing it on the runnable queue.
  57  *
  58  * Called from STG : yes
  59  * Locks assumed   : none
  60  */
  61 #if defined(GRAN)
  62 StgTSO *unblockOne(StgTSO *tso, StgClosure *node);
  63 #elif defined(PAR)
  64 StgTSO *unblockOne(StgTSO *tso, StgClosure *node);
  65 #else
  66 StgTSO *unblockOne(StgTSO *tso);
  67 #endif
  68
  69 //@cindex raiseAsync
  70 /* raiseAsync()
  71  *
  72  * Raises an exception asynchronously in the specified thread.
  73  *
  74  * Called from STG :  yes
  75  * Locks assumed   :  none
  76  */
  77 void raiseAsync(StgTSO *tso, StgClosure *exception);
  78
  79 //@cindex awaitEvent
  80 /* awaitEvent()
  81  *
  82  * Raises an exception asynchronously in the specified thread.
  83  *
  84  * Called from STG :  NO
  85  * Locks assumed   :  sched_mutex
  86  */
  87 void awaitEvent(rtsBool wait);  /* In Select.c */
  88
  89 // ToDo: check whether all fcts below are used in the SMP version, too
  90 //@cindex awaken_blocked_queue
  91 #if defined(GRAN)
  92 void    awaken_blocked_queue(StgBlockingQueueElement *q, StgClosure *node);
  93 void    unlink_from_bq(StgTSO* tso, StgClosure* node);
  94 void    initThread(StgTSO *tso, nat stack_size, StgInt pri);
  95 #elif defined(PAR)
  96 nat     run_queue_len(void);
  97 void    awaken_blocked_queue(StgBlockingQueueElement *q, StgClosure *node);
  98 void    initThread(StgTSO *tso, nat stack_size);
  99 #else
 100 char   *info_type(StgClosure *closure);    // dummy
 101 char   *info_type_by_ip(StgInfoTable *ip); // dummy
 102 void    awaken_blocked_queue(StgTSO *q);
 103 void    initThread(StgTSO *tso, nat stack_size);
 104 #endif
 105
 106 //@node Scheduler Vars and Data Types, Some convenient macros, Scheduler Functions
 107 //@subsection Scheduler Vars and Data Types
 108
 109 //@cindex context_switch
 110 /* Context switch flag.
 111  * Locks required  : sched_mutex
 112  */
 113 extern nat context_switch;
 114 extern rtsBool interrupted;
 115
 116 extern  nat ticks_since_select;
 117
 118 //@cindex Capability
 119 /* Capability type
 120  */
 121 typedef StgRegTable Capability;
 122
 123 /* Free capability list.
 124  * Locks required: sched_mutex.
 125  */
 126 #ifdef SMP
 127 extern Capability *free_capabilities;
 128 extern nat n_free_capabilities;
 129 #else
 130 extern Capability MainRegTable;
 131 #endif
 132
 133 /* Thread queues.
 134  * Locks required  : sched_mutex
 135  */
 136 extern  StgTSO *run_queue_hd, *run_queue_tl;
 137 extern  StgTSO *blocked_queue_hd, *blocked_queue_tl;
 138 extern  StgTSO *all_threads;
 139
 140 #ifdef SMP
 141 //@cindex sched_mutex
 142 //@cindex thread_ready_cond
 143 //@cindex gc_pending_cond
 144 extern pthread_mutex_t sched_mutex;
 145 extern pthread_cond_t  thread_ready_cond;
 146 extern pthread_cond_t  gc_pending_cond;
 147 #endif
 148
 149 //@cindex task_info
 150 #ifdef SMP
 151 typedef struct {
 152   pthread_t id;
 153   double    elapsedtimestart;
 154   double    mut_time;
 155   double    mut_etime;
 156   double    gc_time;
 157   double    gc_etime;
 158 } task_info;
 159
 160 extern task_info *task_ids;
 161 #endif
 162
 163 #if !defined(GRAN)
 164 extern  StgTSO *run_queue_hd, *run_queue_tl;
 165 extern  StgTSO *blocked_queue_hd, *blocked_queue_tl;
 166 #endif
 167
 168 /* Needed by Hugs.
 169  */
 170 void interruptStgRts ( void );
 171
 172 // ?? needed -- HWL
 173 void raiseAsync(StgTSO *tso, StgClosure *exception);
 174 nat  run_queue_len(void);
 175
 176 void resurrectThreads( StgTSO * );
 177
 178 //@node Some convenient macros, Index, Scheduler Vars and Data Types
 179 //@subsection Some convenient macros
 180
 181 /* debugging only
 182  */
 183 #ifdef DEBUG
 184 void printThreadBlockage(StgTSO *tso);
 185 void printThreadStatus(StgTSO *tso);
 186 void printAllThreads(void);
 187 #endif
 188 void print_bq (StgClosure *node);
 189
 190 /* -----------------------------------------------------------------------------
 191  * Some convenient macros...
 192  */
 193
 194 #define END_TSO_QUEUE  ((StgTSO *)(void*)&END_TSO_QUEUE_closure)
 195 #define END_CAF_LIST   ((StgCAF *)(void*)&END_TSO_QUEUE_closure)
 196
 197 //@cindex APPEND_TO_RUN_QUEUE
 198 /* Add a thread to the end of the run queue.
 199  * NOTE: tso->link should be END_TSO_QUEUE before calling this macro.
 200  */
 201 #define APPEND_TO_RUN_QUEUE(tso)                \
 202     ASSERT(tso->link == END_TSO_QUEUE);         \
 203     if (run_queue_hd == END_TSO_QUEUE) {        \
 204       run_queue_hd = tso;                       \
 205     } else {                                    \
 206       run_queue_tl->link = tso;                 \
 207     }                                           \
 208     run_queue_tl = tso;
 209
 210 //@cindex PUSH_ON_RUN_QUEUE
 211 /* Push a thread on the beginning of the run queue.  Used for
 212  * newly awakened threads, so they get run as soon as possible.
 213  */
 214 #define PUSH_ON_RUN_QUEUE(tso)                  \
 215     tso->link = run_queue_hd;                   \
 216       run_queue_hd = tso;                       \
 217     if (run_queue_tl == END_TSO_QUEUE) {        \
 218       run_queue_tl = tso;                       \
 219     }
 220
 221 //@cindex POP_RUN_QUEUE
 222 /* Pop the first thread off the runnable queue.
 223  */
 224 #define POP_RUN_QUEUE()                         \
 225   ({ StgTSO *t = run_queue_hd;                  \
 226     if (t != END_TSO_QUEUE) {                   \
 227       run_queue_hd = t->link;                   \
 228       t->link = END_TSO_QUEUE;                  \
 229       if (run_queue_hd == END_TSO_QUEUE) {      \
 230         run_queue_tl = END_TSO_QUEUE;           \
 231       }                                         \
 232     }                                           \
 233     t;                                          \
 234   })
 235
 236 //@cindex APPEND_TO_BLOCKED_QUEUE
 237 /* Add a thread to the end of the blocked queue.
 238  */
 239 #define APPEND_TO_BLOCKED_QUEUE(tso)            \
 240     ASSERT(tso->link == END_TSO_QUEUE);         \
 241     if (blocked_queue_hd == END_TSO_QUEUE) {    \
 242       blocked_queue_hd = tso;                   \
 243     } else {                                    \
 244       blocked_queue_tl->link = tso;             \
 245     }                                           \
 246     blocked_queue_tl = tso;
 247
 248 //@cindex THREAD_RUNNABLE
 249 /* Signal that a runnable thread has become available, in
 250  * case there are any waiting tasks to execute it.
 251  */
 252 #ifdef SMP
 253 #define THREAD_RUNNABLE()                       \
 254   if (free_capabilities != NULL) {              \
 255      pthread_cond_signal(&thread_ready_cond);   \
 256   }                                             \
 257   context_switch = 1;
 258 #else
 259 #define THREAD_RUNNABLE()  /* nothing */
 260 #endif
 261
 262 //@node Index,  , Some convenient macros
 263 //@subsection Index
 264
 265 //@index
 266 //* APPEND_TO_BLOCKED_QUEUE::  @cindex\s-+APPEND_TO_BLOCKED_QUEUE
 267 //* APPEND_TO_RUN_QUEUE::  @cindex\s-+APPEND_TO_RUN_QUEUE
 268 //* Capability::  @cindex\s-+Capability
 269 //* POP_RUN_QUEUE    ::  @cindex\s-+POP_RUN_QUEUE
 270 //* PUSH_ON_RUN_QUEUE::  @cindex\s-+PUSH_ON_RUN_QUEUE
 271 //* THREAD_RUNNABLE::  @cindex\s-+THREAD_RUNNABLE
 272 //* awaitEvent::  @cindex\s-+awaitEvent
 273 //* awakenBlockedQueue::  @cindex\s-+awakenBlockedQueue
 274 //* awaken_blocked_queue::  @cindex\s-+awaken_blocked_queue
 275 //* context_switch::  @cindex\s-+context_switch
 276 //* exitScheduler::  @cindex\s-+exitScheduler
 277 //* gc_pending_cond::  @cindex\s-+gc_pending_cond
 278 //* initScheduler::  @cindex\s-+initScheduler
 279 //* raiseAsync::  @cindex\s-+raiseAsync
 280 //* sched_mutex::  @cindex\s-+sched_mutex
 281 //* startTasks::  @cindex\s-+startTasks
 282 //* task_info::  @cindex\s-+task_info
 283 //* thread_ready_cond::  @cindex\s-+thread_ready_cond
 284 //* unblockOne::  @cindex\s-+unblockOne
 285 //@end index