ghc/rts/Schedule.h

   1 /* -----------------------------------------------------------------------------
   2  * $Id: Schedule.h,v 1.15 2000/01/14 14:06:48 hwloidl 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 // debugging only
 107 #ifdef DEBUG
 108 extern void printThreadBlockage(StgTSO *tso);
 109 #endif
 110 void    print_bq (StgClosure *node);
 111
 112 //@node Scheduler Vars and Data Types, Some convenient macros, Scheduler Functions
 113 //@subsection Scheduler Vars and Data Types
 114
 115 //@cindex context_switch
 116 /* Context switch flag.
 117  * Locks required  : sched_mutex
 118  */
 119 extern nat context_switch;
 120 extern rtsBool interrupted;
 121
 122 extern  nat ticks_since_select;
 123
 124 //@cindex Capability
 125 /* Capability type
 126  */
 127 typedef StgRegTable Capability;
 128
 129 /* Free capability list.
 130  * Locks required: sched_mutex.
 131  */
 132 #ifdef SMP
 133 extern Capability *free_capabilities;
 134 extern nat n_free_capabilities;
 135 #else
 136 extern Capability MainRegTable;
 137 #endif
 138
 139 /* Thread queues.
 140  * Locks required  : sched_mutex
 141  */
 142 extern  StgTSO *run_queue_hd, *run_queue_tl;
 143 extern  StgTSO *blocked_queue_hd, *blocked_queue_tl;
 144
 145 #ifdef SMP
 146 //@cindex sched_mutex
 147 //@cindex thread_ready_cond
 148 //@cindex gc_pending_cond
 149 extern pthread_mutex_t sched_mutex;
 150 extern pthread_cond_t  thread_ready_cond;
 151 extern pthread_cond_t  gc_pending_cond;
 152 #endif
 153
 154 //@cindex task_info
 155 #ifdef SMP
 156 typedef struct {
 157   pthread_t id;
 158   double    elapsedtimestart;
 159   double    mut_time;
 160   double    mut_etime;
 161   double    gc_time;
 162   double    gc_etime;
 163 } task_info;
 164
 165 extern task_info *task_ids;
 166 #endif
 167
 168 #if !defined(GRAN)
 169 extern  StgTSO *run_queue_hd, *run_queue_tl;
 170 extern  StgTSO *blocked_queue_hd, *blocked_queue_tl;
 171 #endif
 172
 173 /* Needed by Hugs.
 174  */
 175 void interruptStgRts ( void );
 176
 177 // ?? needed -- HWL
 178 void raiseAsync(StgTSO *tso, StgClosure *exception);
 179 nat  run_queue_len(void);
 180
 181 //@node Some convenient macros, Index, Scheduler Vars and Data Types
 182 //@subsection Some convenient macros
 183
 184 /* -----------------------------------------------------------------------------
 185  * Some convenient macros...
 186  */
 187
 188 #define END_TSO_QUEUE  ((StgTSO *)(void*)&END_TSO_QUEUE_closure)
 189 #define END_CAF_LIST   ((StgCAF *)(void*)&END_TSO_QUEUE_closure)
 190
 191 //@cindex APPEND_TO_RUN_QUEUE
 192 /* Add a thread to the end of the run queue.
 193  * NOTE: tso->link should be END_TSO_QUEUE before calling this macro.
 194  */
 195 #define APPEND_TO_RUN_QUEUE(tso)                \
 196     ASSERT(tso->link == END_TSO_QUEUE);         \
 197     if (run_queue_hd == END_TSO_QUEUE) {        \
 198       run_queue_hd = tso;                       \
 199     } else {                                    \
 200       run_queue_tl->link = tso;                 \
 201     }                                           \
 202     run_queue_tl = tso;
 203
 204 //@cindex PUSH_ON_RUN_QUEUE
 205 /* Push a thread on the beginning of the run queue.  Used for
 206  * newly awakened threads, so they get run as soon as possible.
 207  */
 208 #define PUSH_ON_RUN_QUEUE(tso)                  \
 209     tso->link = run_queue_hd;                   \
 210       run_queue_hd = tso;                       \
 211     if (run_queue_tl == END_TSO_QUEUE) {        \
 212       run_queue_tl = tso;                       \
 213     }
 214
 215 //@cindex POP_RUN_QUEUE
 216 /* Pop the first thread off the runnable queue.
 217  */
 218 #define POP_RUN_QUEUE()                         \
 219   ({ StgTSO *t = run_queue_hd;                  \
 220     if (t != END_TSO_QUEUE) {                   \
 221       run_queue_hd = t->link;                   \
 222       t->link = END_TSO_QUEUE;                  \
 223       if (run_queue_hd == END_TSO_QUEUE) {      \
 224         run_queue_tl = END_TSO_QUEUE;           \
 225       }                                         \
 226     }                                           \
 227     t;                                          \
 228   })
 229
 230 //@cindex APPEND_TO_BLOCKED_QUEUE
 231 /* Add a thread to the end of the blocked queue.
 232  */
 233 #define APPEND_TO_BLOCKED_QUEUE(tso)            \
 234     ASSERT(tso->link == END_TSO_QUEUE);         \
 235     if (blocked_queue_hd == END_TSO_QUEUE) {    \
 236       blocked_queue_hd = tso;                   \
 237     } else {                                    \
 238       blocked_queue_tl->link = tso;             \
 239     }                                           \
 240     blocked_queue_tl = tso;
 241
 242 //@cindex THREAD_RUNNABLE
 243 /* Signal that a runnable thread has become available, in
 244  * case there are any waiting tasks to execute it.
 245  */
 246 #ifdef SMP
 247 #define THREAD_RUNNABLE()                       \
 248   if (free_capabilities != NULL) {              \
 249      pthread_cond_signal(&thread_ready_cond);   \
 250   }                                             \
 251   context_switch = 1;
 252 #else
 253 #define THREAD_RUNNABLE()  /* nothing */
 254 #endif
 255
 256 //@node Index,  , Some convenient macros
 257 //@subsection Index
 258
 259 //@index
 260 //* APPEND_TO_BLOCKED_QUEUE::  @cindex\s-+APPEND_TO_BLOCKED_QUEUE
 261 //* APPEND_TO_RUN_QUEUE::  @cindex\s-+APPEND_TO_RUN_QUEUE
 262 //* Capability::  @cindex\s-+Capability
 263 //* POP_RUN_QUEUE    ::  @cindex\s-+POP_RUN_QUEUE
 264 //* PUSH_ON_RUN_QUEUE::  @cindex\s-+PUSH_ON_RUN_QUEUE
 265 //* THREAD_RUNNABLE::  @cindex\s-+THREAD_RUNNABLE
 266 //* awaitEvent::  @cindex\s-+awaitEvent
 267 //* awakenBlockedQueue::  @cindex\s-+awakenBlockedQueue
 268 //* awaken_blocked_queue::  @cindex\s-+awaken_blocked_queue
 269 //* context_switch::  @cindex\s-+context_switch
 270 //* exitScheduler::  @cindex\s-+exitScheduler
 271 //* gc_pending_cond::  @cindex\s-+gc_pending_cond
 272 //* initScheduler::  @cindex\s-+initScheduler
 273 //* raiseAsync::  @cindex\s-+raiseAsync
 274 //* sched_mutex::  @cindex\s-+sched_mutex
 275 //* startTasks::  @cindex\s-+startTasks
 276 //* task_info::  @cindex\s-+task_info
 277 //* thread_ready_cond::  @cindex\s-+thread_ready_cond
 278 //* unblockOne::  @cindex\s-+unblockOne
 279 //@end index