1 /* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002 Free Software Foundation, Inc.
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2, or (at your option)
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this software; see the file COPYING. If not, write to
15 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
16 * Boston, MA 02111-1307 USA
18 * As a special exception, the Free Software Foundation gives permission
19 * for additional uses of the text contained in its release of GUILE.
21 * The exception is that, if you link the GUILE library with other files
22 * to produce an executable, this does not by itself cause the
23 * resulting executable to be covered by the GNU General Public License.
24 * Your use of that executable is in no way restricted on account of
25 * linking the GUILE library code into it.
27 * This exception does not however invalidate any other reasons why
28 * the executable file might be covered by the GNU General Public License.
30 * This exception applies only to the code released by the
31 * Free Software Foundation under the name GUILE. If you copy
32 * code from other Free Software Foundation releases into a copy of
33 * GUILE, as the General Public License permits, the exception does
34 * not apply to the code that you add in this way. To avoid misleading
35 * anyone as to the status of such modified files, you must delete
36 * this exception notice from them.
38 * If you write modifications of your own for GUILE, it is your choice
39 * whether to permit this exception to apply to your modifications.
40 * If you do not wish that, delete this exception notice. */
45 /* This file implements nice Scheme level threads on top of the gastly
54 #include "libguile/_scm.h"
55 #include "libguile/validate.h"
56 #include "libguile/root.h"
57 #include "libguile/eval.h"
58 #include "libguile/async.h"
59 #include "libguile/ports.h"
60 #include "libguile/threads.h"
61 #include "libguile/dynwind.h"
62 #include "libguile/iselect.h"
69 return scm_cons (SCM_EOL
, SCM_EOL
);
73 enqueue (SCM q
, SCM t
)
75 SCM c
= scm_cons (t
, SCM_EOL
);
76 if (SCM_NULLP (SCM_CDR (q
)))
79 SCM_SETCDR (SCM_CAR (q
), c
);
85 remqueue (SCM q
, SCM c
)
88 for (p
= SCM_CDR (q
); !SCM_NULLP (p
); p
= SCM_CDR (p
))
92 if (SCM_EQ_P (c
, SCM_CAR (q
)))
93 SCM_SETCAR (q
, SCM_CDR (c
));
94 SCM_SETCDR (prev
, SCM_CDR (c
));
110 SCM_SETCDR (q
, SCM_CDR (c
));
111 if (SCM_NULLP (SCM_CDR (q
)))
112 SCM_SETCAR (q
, SCM_EOL
);
119 #define THREAD_INITIALIZED_P(t) (t->base != NULL)
125 scm_t_cond sleep_cond
;
126 struct scm_thread
*next_waiting
;
128 /* This mutex represents this threads right to access the heap.
129 That right can temporarily be taken away by the GC. */
130 scm_t_mutex heap_mutex
;
131 int clear_freelists_p
; /* set if GC was done while thread was asleep */
133 scm_root_state
*root
;
141 /* For keeping track of the stack and registers. */
149 make_thread (SCM creation_protects
)
153 z
= scm_make_smob (scm_tc16_thread
);
154 t
= SCM_THREAD_DATA (z
);
156 t
->result
= creation_protects
;
158 t
->joining_threads
= make_queue ();
159 scm_i_plugin_cond_init (&t
->sleep_cond
, 0);
160 scm_i_plugin_mutex_init (&t
->heap_mutex
, 0);
161 t
->clear_freelists_p
= 0;
167 init_thread_creatant (SCM thread
,
170 scm_thread
*t
= SCM_THREAD_DATA (thread
);
171 t
->thread
= scm_thread_self ();
177 thread_mark (SCM obj
)
179 scm_thread
*t
= SCM_THREAD_DATA (obj
);
180 scm_gc_mark (t
->result
);
181 scm_gc_mark (t
->joining_threads
);
182 return t
->root
->handle
; /* mark root-state of this thread */
186 thread_print (SCM exp
, SCM port
, scm_print_state
*pstate SCM_UNUSED
)
188 scm_thread
*t
= SCM_THREAD_DATA (exp
);
189 scm_puts ("#<thread ", port
);
190 scm_intprint ((unsigned long)t
, 16, port
);
191 scm_putc ('>', port
);
196 thread_free (SCM obj
)
198 scm_thread
*t
= SCM_THREAD_DATA (obj
);
201 scm_gc_free (t
, sizeof (*t
), "thread");
207 #define cur_thread (SCM_CURRENT_THREAD->handle)
208 scm_t_key scm_i_thread_key
;
209 scm_t_key scm_i_root_state_key
;
212 scm_i_set_thread_data (void *data
)
214 scm_thread
*t
= SCM_CURRENT_THREAD
;
215 scm_setspecific (scm_i_root_state_key
, data
);
216 t
->root
= (scm_root_state
*)data
;
220 resume (scm_thread
*t
)
223 if (t
->clear_freelists_p
)
225 *SCM_FREELIST_LOC (scm_i_freelist
) = SCM_EOL
;
226 *SCM_FREELIST_LOC (scm_i_freelist2
) = SCM_EOL
;
227 t
->clear_freelists_p
= 0;
232 scm_i_enter_guile (scm_thread
*t
)
234 scm_i_plugin_mutex_lock (&t
->heap_mutex
);
241 scm_thread
*c
= SCM_CURRENT_THREAD
;
243 /* record top of stack for the GC */
244 c
->top
= (SCM_STACKITEM
*)&c
;
245 /* save registers. */
246 SCM_FLUSH_REGISTER_WINDOWS
;
255 scm_thread
*t
= suspend ();
256 scm_i_plugin_mutex_unlock (&t
->heap_mutex
);
260 /* Put the current thread to sleep until it is explicitely unblocked.
266 scm_thread
*t
= suspend ();
267 err
= scm_i_plugin_cond_wait (&t
->sleep_cond
, &t
->heap_mutex
);
272 /* Put the current thread to sleep until it is explicitely unblocked
273 or until a signal arrives or until time AT (absolute time) is
274 reached. Return 0 when it has been unblocked; errno otherwise.
277 timed_block (const struct timespec
*at
)
280 scm_thread
*t
= suspend ();
281 err
= scm_i_plugin_cond_timedwait (&t
->sleep_cond
, &t
->heap_mutex
, at
);
286 /* Unblock a sleeping thread.
289 unblock (scm_thread
*t
)
291 scm_i_plugin_cond_signal (&t
->sleep_cond
);
294 /*** Thread creation */
296 static scm_t_mutex thread_admin_mutex
;
297 static SCM all_threads
;
298 static int thread_count
;
300 typedef struct launch_data
{
303 scm_t_catch_body body
;
305 scm_t_catch_handler handler
;
310 body_bootstrip (launch_data
* data
)
312 /* First save the new root continuation */
313 data
->rootcont
= scm_root
->rootcont
;
314 return (data
->body
) (data
->body_data
);
318 handler_bootstrip (launch_data
* data
, SCM tag
, SCM throw_args
)
320 scm_root
->rootcont
= data
->rootcont
;
321 return (data
->handler
) (data
->handler_data
, tag
, throw_args
);
325 really_launch (SCM_STACKITEM
*base
, launch_data
*data
)
329 thread
= data
->thread
;
330 t
= SCM_THREAD_DATA (thread
);
331 SCM_FREELIST_CREATE (scm_i_freelist
);
332 SCM_FREELIST_CREATE (scm_i_freelist2
);
333 scm_setspecific (scm_i_thread_key
, t
);
334 scm_setspecific (scm_i_root_state_key
, t
->root
);
335 scm_i_plugin_mutex_lock (&t
->heap_mutex
); /* ensure that we "own" the heap */
336 init_thread_creatant (thread
, base
); /* must own the heap */
338 data
->rootcont
= SCM_BOOL_F
;
340 scm_internal_cwdr ((scm_t_catch_body
) body_bootstrip
,
342 (scm_t_catch_handler
) handler_bootstrip
,
344 scm_i_leave_guile (); /* release the heap */
347 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
348 all_threads
= scm_delq_x (thread
, all_threads
);
351 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
353 scm_thread_detach (t
->thread
);
357 launch_thread (void *p
)
359 really_launch ((SCM_STACKITEM
*)&p
, (launch_data
*)p
);
364 create_thread (scm_t_catch_body body
, void *body_data
,
365 scm_t_catch_handler handler
, void *handler_data
,
370 /* Make new thread. The first thing the new thread will do is to
371 lock guile_mutex. Thus, we can safely complete its
372 initialization after creating it. While the new thread starts,
373 all its data is protected via all_threads.
383 /* Unwind wind chain. */
384 old_winds
= scm_dynwinds
;
385 scm_dowinds (SCM_EOL
, scm_ilength (scm_root
->dynwinds
));
387 /* Allocate thread locals. */
388 root
= scm_make_root (scm_root
->handle
);
389 data
= scm_malloc (sizeof (launch_data
));
392 thread
= make_thread (protects
);
393 data
->thread
= thread
;
395 data
->body_data
= body_data
;
396 data
->handler
= handler
;
397 data
->handler_data
= handler_data
;
398 t
= SCM_THREAD_DATA (thread
);
399 /* must initialize root state pointer before the thread is linked
401 t
->root
= SCM_ROOT_STATE (root
);
403 /* In order to avoid the need of synchronization between parent
404 and child thread, we need to insert the child into all_threads
407 SCM new_threads
= scm_cons (thread
, SCM_BOOL_F
); /* could cause GC */
408 scm_thread
*parent
= scm_i_leave_guile (); /* to prevent deadlock */
409 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
410 SCM_SETCDR (new_threads
, all_threads
);
411 all_threads
= new_threads
;
413 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
415 scm_remember_upto_here_1 (root
);
417 scm_i_enter_guile (parent
);
420 err
= scm_i_plugin_thread_create (&th
, 0, launch_thread
, (void *) data
);
423 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
424 all_threads
= scm_delq_x (thread
, all_threads
);
425 ((scm_thread
*) SCM_THREAD_DATA(thread
))->exited
= 1;
427 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
430 /* Return to old dynamic context. */
431 scm_dowinds (old_winds
, - scm_ilength (old_winds
));
436 scm_syserror ("create-thread");
443 SCM_DEFINE (scm_call_with_new_thread
, "call-with-new-thread", 2, 0, 0,
444 (SCM thunk
, SCM handler
),
445 "Evaluate @var{(thunk)} in a new thread, and new dynamic context, "
446 "returning a new thread object representing the thread. "
447 "If an error occurs during evaluation, call error-thunk, passing it an "
448 "error code describing the condition. "
449 "If this happens, the error-thunk is called outside the scope of the new "
450 "root -- it is called in the same dynamic context in which "
451 "with-new-thread was evaluated, but not in the callers thread. "
452 "All the evaluation rules for dynamic roots apply to threads.")
453 #define FUNC_NAME s_scm_call_with_new_thread
455 SCM_ASSERT (SCM_NFALSEP (scm_thunk_p (thunk
)), thunk
, SCM_ARG1
, FUNC_NAME
);
456 SCM_ASSERT (SCM_NFALSEP (scm_procedure_p (handler
)), handler
, SCM_ARG2
,
459 return create_thread ((scm_t_catch_body
) scm_call_0
, thunk
,
460 (scm_t_catch_handler
) scm_apply_1
, handler
,
461 scm_cons (thunk
, handler
));
465 SCM_DEFINE (scm_join_thread
, "join-thread", 1, 0, 0,
467 "Suspend execution of the calling thread until the target @var{thread} "
468 "terminates, unless the target @var{thread} has already terminated. ")
469 #define FUNC_NAME s_scm_join_thread
474 SCM_VALIDATE_THREAD (1, thread
);
475 if (SCM_EQ_P (cur_thread
, thread
))
476 SCM_MISC_ERROR ("can not join the current thread", SCM_EOL
);
478 t
= SCM_THREAD_DATA (thread
);
481 scm_thread
*c
= scm_i_leave_guile ();
482 while (!THREAD_INITIALIZED_P (t
))
484 scm_thread_join (t
->thread
, 0);
485 scm_i_enter_guile (c
);
488 t
->result
= SCM_BOOL_F
;
495 /* We implement our own mutex type since we want them to be 'fair', we
496 want to do fancy things while waiting for them (like running
497 asyncs) and we want to support waiting on many things at once.
498 Also, we might add things that are nice for debugging.
501 typedef struct fair_mutex
{
502 /* the thread currently owning the mutex, or SCM_BOOL_F. */
506 /* how much the owner owns us. */
508 /* the threads waiting for this mutex. */
513 fair_mutex_mark (SCM mx
)
515 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
516 scm_gc_mark (m
->owner
);
520 SCM_DEFINE (scm_make_fair_mutex
, "make-fair-mutex", 0, 0, 0,
522 "Create a new fair mutex object. ")
523 #define FUNC_NAME s_scm_make_fair_mutex
525 SCM mx
= scm_make_smob (scm_tc16_fair_mutex
);
526 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
527 scm_i_plugin_mutex_init (&m
->lock
, 0);
529 m
->owner
= SCM_BOOL_F
;
531 m
->waiting
= make_queue ();
537 fair_mutex_lock (fair_mutex
*m
)
539 scm_i_plugin_mutex_lock (&m
->lock
);
541 /* Need to wait if another thread is just temporarily unlocking.
542 This is happens very seldom and only when the other thread is
543 between scm_mutex_unlock and scm_i_plugin_mutex_lock below. */
549 if (m
->owner
== SCM_BOOL_F
)
550 m
->owner
= cur_thread
;
551 else if (m
->owner
== cur_thread
)
557 SCM c
= enqueue (m
->waiting
, cur_thread
);
559 /* Note: It's important that m->lock is never locked for
560 any longer amount of time since that could prevent GC */
561 scm_i_plugin_mutex_unlock (&m
->lock
);
563 if (m
->owner
== cur_thread
)
565 scm_i_plugin_mutex_lock (&m
->lock
);
566 remqueue (m
->waiting
, c
);
567 scm_i_plugin_mutex_unlock (&m
->lock
);
571 scm_i_plugin_mutex_lock (&m
->lock
);
574 scm_i_plugin_mutex_unlock (&m
->lock
);
579 fair_mutex_trylock (fair_mutex
*m
)
581 scm_i_plugin_mutex_lock (&m
->lock
);
582 if (m
->owner
== SCM_BOOL_F
)
583 m
->owner
= cur_thread
;
584 else if (m
->owner
== cur_thread
)
588 scm_i_plugin_mutex_unlock (&m
->lock
);
591 scm_i_plugin_mutex_unlock (&m
->lock
);
596 fair_mutex_unlock (fair_mutex
*m
)
598 scm_i_plugin_mutex_lock (&m
->lock
);
599 if (m
->owner
!= cur_thread
)
601 scm_i_plugin_mutex_unlock (&m
->lock
);
604 else if (m
->level
> 0)
608 SCM next
= dequeue (m
->waiting
);
609 if (!SCM_FALSEP (next
))
612 unblock (SCM_THREAD_DATA (next
));
615 m
->owner
= SCM_BOOL_F
;
617 scm_i_plugin_mutex_unlock (&m
->lock
);
621 /*** Fair condition variables */
623 /* Like mutexes, we implement our own condition variables using the
627 typedef struct fair_cond
{
629 /* the threads waiting for this condition. */
634 fair_cond_mark (SCM cv
)
636 fair_cond
*c
= SCM_CONDVAR_DATA (cv
);
640 SCM_DEFINE (scm_make_fair_condition_variable
, "make-fair-condition-variable", 0, 0, 0,
642 "Make a new fair condition variable.")
643 #define FUNC_NAME s_scm_make_fair_condition_variable
645 SCM cv
= scm_make_smob (scm_tc16_fair_condvar
);
646 fair_cond
*c
= SCM_CONDVAR_DATA (cv
);
647 scm_i_plugin_mutex_init (&c
->lock
, 0);
648 c
->waiting
= make_queue ();
654 fair_cond_timedwait (fair_cond
*c
,
656 const struct timespec
*waittime
)
659 scm_i_plugin_mutex_lock (&c
->lock
);
663 enqueue (c
->waiting
, cur_thread
);
664 scm_i_plugin_mutex_unlock (&c
->lock
);
665 fair_mutex_unlock (m
); /*fixme* - not thread safe */
666 if (waittime
== NULL
)
669 err
= timed_block (waittime
);
673 /* XXX - check whether we have been signalled. */
680 fair_cond_signal (fair_cond
*c
)
683 scm_i_plugin_mutex_lock (&c
->lock
);
684 if (!SCM_FALSEP (th
= dequeue (c
->waiting
)))
685 unblock (SCM_THREAD_DATA (th
));
686 scm_i_plugin_mutex_unlock (&c
->lock
);
691 fair_cond_broadcast (fair_cond
*c
)
694 scm_i_plugin_mutex_lock (&c
->lock
);
695 while (!SCM_FALSEP (th
= dequeue (c
->waiting
)))
696 unblock (SCM_THREAD_DATA (th
));
697 scm_i_plugin_mutex_unlock (&c
->lock
);
703 SCM_DEFINE (scm_make_mutex
, "make-mutex", 0, 0, 0,
705 "Create a new mutex object. ")
706 #define FUNC_NAME s_scm_make_mutex
708 SCM mx
= scm_make_smob (scm_tc16_mutex
);
709 scm_i_plugin_mutex_init (SCM_MUTEX_DATA (mx
), 0);
714 /*fixme* change documentation */
715 SCM_DEFINE (scm_lock_mutex
, "lock-mutex", 1, 0, 0,
717 "Lock @var{mutex}. If the mutex is already locked, the calling thread "
718 "blocks until the mutex becomes available. The function returns when "
719 "the calling thread owns the lock on @var{mutex}. Locking a mutex that "
720 "a thread already owns will succeed right away and will not block the "
721 "thread. That is, Guile's mutexes are @emph{recursive}. ")
722 #define FUNC_NAME s_scm_lock_mutex
725 SCM_VALIDATE_MUTEX (1, mx
);
727 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
728 err
= fair_mutex_lock (SCM_MUTEX_DATA (mx
));
731 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
732 scm_thread
*t
= scm_i_leave_guile ();
733 err
= scm_i_plugin_mutex_lock (m
);
734 scm_i_enter_guile (t
);
746 SCM_DEFINE (scm_try_mutex
, "try-mutex", 1, 0, 0,
748 "Try to lock @var{mutex}. If the mutex is already locked by someone "
749 "else, return @code{#f}. Else lock the mutex and return @code{#t}. ")
750 #define FUNC_NAME s_scm_try_mutex
753 SCM_VALIDATE_MUTEX (1, mx
);
755 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
756 err
= fair_mutex_trylock (SCM_MUTEX_DATA (mx
));
759 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
760 scm_thread
*t
= scm_i_leave_guile ();
761 err
= scm_i_plugin_mutex_trylock (m
);
762 scm_i_enter_guile (t
);
778 SCM_DEFINE (scm_unlock_mutex
, "unlock-mutex", 1, 0, 0,
780 "Unlocks @var{mutex} if the calling thread owns the lock on "
781 "@var{mutex}. Calling unlock-mutex on a mutex not owned by the current "
782 "thread results in undefined behaviour. Once a mutex has been unlocked, "
783 "one thread blocked on @var{mutex} is awakened and grabs the mutex "
784 "lock. Every call to @code{lock-mutex} by this thread must be matched "
785 "with a call to @code{unlock-mutex}. Only the last call to "
786 "@code{unlock-mutex} will actually unlock the mutex. ")
787 #define FUNC_NAME s_scm_unlock_mutex
790 SCM_VALIDATE_MUTEX (1, mx
);
792 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
794 err
= fair_mutex_unlock (SCM_MUTEX_DATA (mx
));
797 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
798 if (m
->owner
!= cur_thread
)
800 if (m
->owner
== SCM_BOOL_F
)
801 SCM_MISC_ERROR ("mutex not locked", SCM_EOL
);
803 SCM_MISC_ERROR ("mutex not locked by this thread", SCM_EOL
);
809 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
810 err
= scm_i_plugin_mutex_unlock (m
);
822 /*** Condition variables */
824 SCM_DEFINE (scm_make_condition_variable
, "make-condition-variable", 0, 0, 0,
826 "Make a new condition variable.")
827 #define FUNC_NAME s_scm_make_condition_variable
829 SCM cv
= scm_make_smob (scm_tc16_condvar
);
830 scm_i_plugin_cond_init (SCM_CONDVAR_DATA (cv
), 0);
835 SCM_DEFINE (scm_timed_wait_condition_variable
, "wait-condition-variable", 2, 1, 0,
836 (SCM cv
, SCM mx
, SCM t
),
837 "Wait until @var{cond-var} has been signalled. While waiting, "
838 "@var{mutex} is atomically unlocked (as with @code{unlock-mutex}) and "
839 "is locked again when this function returns. When @var{time} is given, "
840 "it specifies a point in time where the waiting should be aborted. It "
841 "can be either a integer as returned by @code{current-time} or a pair "
842 "as returned by @code{gettimeofday}. When the waiting is aborted the "
843 "mutex is locked and @code{#f} is returned. When the condition "
844 "variable is in fact signalled, the mutex is also locked and @code{#t} "
846 #define FUNC_NAME s_scm_timed_wait_condition_variable
848 struct timespec waittime
;
851 SCM_VALIDATE_CONDVAR (1, cv
);
852 SCM_VALIDATE_MUTEX (2, mx
);
853 if (!((SCM_TYP16 (cv
) == scm_tc16_condvar
854 && SCM_TYP16 (mx
) == scm_tc16_mutex
)
855 || (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
856 && SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)))
857 SCM_MISC_ERROR ("Condition variable and mutex are of different kinds.",
864 SCM_VALIDATE_UINT_COPY (3, SCM_CAR (t
), waittime
.tv_sec
);
865 SCM_VALIDATE_UINT_COPY (3, SCM_CDR (t
), waittime
.tv_nsec
);
866 waittime
.tv_nsec
*= 1000;
870 SCM_VALIDATE_UINT_COPY (3, t
, waittime
.tv_sec
);
871 waittime
.tv_nsec
= 0;
875 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
876 err
= fair_cond_timedwait (SCM_CONDVAR_DATA (cv
),
878 SCM_UNBNDP (t
) ? NULL
: &waittime
);
881 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
882 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
883 scm_thread
*t
= scm_i_leave_guile ();
884 err
= scm_i_plugin_cond_wait (c
, m
);
885 scm_i_enter_guile (t
);
897 SCM_DEFINE (scm_signal_condition_variable
, "signal-condition-variable", 1, 0, 0,
899 "Wake up one thread that is waiting for @var{cv}")
900 #define FUNC_NAME s_scm_signal_condition_variable
902 SCM_VALIDATE_CONDVAR (1, cv
);
903 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
904 fair_cond_signal (SCM_CONDVAR_DATA (cv
));
907 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
908 scm_i_plugin_cond_signal (c
);
914 SCM_DEFINE (scm_broadcast_condition_variable
, "broadcast-condition-variable", 1, 0, 0,
916 "Wake up all threads that are waiting for @var{cv}. ")
917 #define FUNC_NAME s_scm_broadcast_condition_variable
919 SCM_VALIDATE_CONDVAR (1, cv
);
920 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
921 fair_cond_broadcast (SCM_CONDVAR_DATA (cv
));
924 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
925 scm_i_plugin_cond_broadcast (c
);
931 /*** Marking stacks */
933 /* XXX - what to do with this? Do we need to handle this for blocked
937 # define SCM_MARK_BACKING_STORE() do { \
939 SCM_STACKITEM * top, * bot; \
941 scm_mark_locations ((SCM_STACKITEM *) &ctx.uc_mcontext, \
942 ((size_t) (sizeof (SCM_STACKITEM) - 1 + sizeof ctx.uc_mcontext) \
943 / sizeof (SCM_STACKITEM))); \
944 bot = (SCM_STACKITEM *) __libc_ia64_register_backing_store_base; \
945 top = (SCM_STACKITEM *) ctx.uc_mcontext.sc_ar_bsp; \
946 scm_mark_locations (bot, top - bot); } while (0)
948 # define SCM_MARK_BACKING_STORE()
952 scm_threads_mark_stacks (void)
955 for (c
= all_threads
; !SCM_NULLP (c
); c
= SCM_CDR (c
))
957 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (c
));
958 if (!THREAD_INITIALIZED_P (t
))
960 /* Not fully initialized yet. */
967 if (t
->thread
!= scm_thread_self ())
971 /* stack_len is long rather than sizet in order to guarantee
972 that &stack_len is long aligned */
973 #ifdef STACK_GROWS_UP
974 stack_len
= ((SCM_STACKITEM
*) (&t
) -
975 (SCM_STACKITEM
*) thread
->base
);
977 /* Protect from the C stack. This must be the first marking
978 * done because it provides information about what objects
979 * are "in-use" by the C code. "in-use" objects are those
980 * for which the information about length and base address must
981 * remain usable. This requirement is stricter than a liveness
982 * requirement -- in particular, it constrains the implementation
985 SCM_FLUSH_REGISTER_WINDOWS
;
986 /* This assumes that all registers are saved into the jmp_buf */
987 setjmp (scm_save_regs_gc_mark
);
988 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
989 ((size_t) sizeof scm_save_regs_gc_mark
990 / sizeof (SCM_STACKITEM
)));
992 scm_mark_locations (((size_t) t
->base
,
995 stack_len
= ((SCM_STACKITEM
*) t
->base
-
996 (SCM_STACKITEM
*) (&t
));
998 /* Protect from the C stack. This must be the first marking
999 * done because it provides information about what objects
1000 * are "in-use" by the C code. "in-use" objects are those
1001 * for which the information about length and base address must
1002 * remain usable. This requirement is stricter than a liveness
1003 * requirement -- in particular, it constrains the implementation
1006 SCM_FLUSH_REGISTER_WINDOWS
;
1007 /* This assumes that all registers are saved into the jmp_buf */
1008 setjmp (scm_save_regs_gc_mark
);
1009 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
1010 ((size_t) sizeof scm_save_regs_gc_mark
1011 / sizeof (SCM_STACKITEM
)));
1013 scm_mark_locations ((SCM_STACKITEM
*) &t
,
1019 /* Suspended thread */
1020 #ifdef STACK_GROWS_UP
1021 long stack_len
= t
->top
- t
->base
;
1022 scm_mark_locations (t
->base
, stack_len
);
1024 long stack_len
= t
->base
- t
->top
;
1025 scm_mark_locations (t
->top
, stack_len
);
1027 scm_mark_locations ((SCM_STACKITEM
*) t
->regs
,
1028 ((size_t) sizeof(t
->regs
)
1029 / sizeof (SCM_STACKITEM
)));
1037 scm_internal_select (int nfds
,
1038 SELECT_TYPE
*readfds
,
1039 SELECT_TYPE
*writefds
,
1040 SELECT_TYPE
*exceptfds
,
1041 struct timeval
*timeout
)
1044 scm_thread
*c
= scm_i_leave_guile ();
1045 res
= scm_i_plugin_select (nfds
, readfds
, writefds
, exceptfds
, timeout
);
1047 scm_i_enter_guile (c
);
1053 /* Low-level C API */
1056 scm_spawn_thread (scm_t_catch_body body
, void *body_data
,
1057 scm_t_catch_handler handler
, void *handler_data
)
1059 return create_thread (body
, body_data
, handler
, handler_data
, SCM_BOOL_F
);
1063 scm_mutex_lock (scm_t_mutex
*m
)
1065 scm_thread
*t
= scm_i_leave_guile ();
1066 int res
= scm_i_plugin_mutex_lock (m
);
1067 scm_i_enter_guile (t
);
1072 scm_cond_wait (scm_t_cond
*c
, scm_t_mutex
*m
)
1074 scm_thread
*t
= scm_i_leave_guile ();
1075 scm_i_plugin_cond_wait (c
, m
);
1076 scm_i_enter_guile (t
);
1081 scm_cond_timedwait (scm_t_cond
*c
, scm_t_mutex
*m
, const struct timespec
*wt
)
1083 scm_thread
*t
= scm_i_leave_guile ();
1084 int res
= scm_i_plugin_cond_timedwait (c
, m
, wt
);
1085 scm_i_enter_guile (t
);
1092 scm_i_enter_guile (SCM_CURRENT_THREAD
);
1098 scm_i_leave_guile ();
1102 scm_thread_usleep (unsigned long usecs
)
1105 tv
.tv_usec
= usecs
% 1000000;
1106 tv
.tv_sec
= usecs
/ 1000000;
1107 scm_internal_select (0, NULL
, NULL
, NULL
, &tv
);
1108 return tv
.tv_usec
+ tv
.tv_sec
*1000000;
1112 scm_thread_sleep (unsigned long secs
)
1117 scm_internal_select (0, NULL
, NULL
, NULL
, &tv
);
1123 SCM_DEFINE (scm_current_thread
, "current-thread", 0, 0, 0,
1125 "Return the thread that called this function.")
1126 #define FUNC_NAME s_scm_current_thread
1132 SCM_DEFINE (scm_all_threads
, "all-threads", 0, 0, 0,
1134 "Return a list of all threads.")
1135 #define FUNC_NAME s_scm_all_threads
1142 scm_i_thread_root (SCM thread
)
1144 return ((scm_thread
*) SCM_THREAD_DATA (thread
))->root
;
1147 SCM_DEFINE (scm_thread_exited_p
, "thread-exited?", 1, 0, 0,
1149 "Return @code{#t} iff @var{thread} has exited.\n")
1150 #define FUNC_NAME s_scm_thread_exited_p
1152 return SCM_BOOL (scm_c_thread_exited_p (thread
));
1157 scm_c_thread_exited_p (SCM thread
)
1158 #define FUNC_NAME s_scm_thread_exited_p
1161 SCM_VALIDATE_THREAD (1, thread
);
1162 t
= SCM_THREAD_DATA (thread
);
1167 static scm_t_cond wake_up_cond
;
1168 int scm_i_thread_go_to_sleep
;
1169 static scm_t_mutex gc_section_mutex
;
1170 static scm_thread
*gc_section_owner
;
1171 static int gc_section_count
= 0;
1172 static int threads_initialized_p
= 0;
1175 scm_i_thread_put_to_sleep ()
1177 SCM_REC_CRITICAL_SECTION_START (gc_section
);
1178 if (threads_initialized_p
&& gc_section_count
== 1)
1181 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
1182 threads
= all_threads
;
1183 /* Signal all threads to go to sleep */
1184 scm_i_thread_go_to_sleep
= 1;
1185 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1186 if (SCM_CAR (threads
) != cur_thread
)
1188 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1189 scm_i_plugin_mutex_lock (&t
->heap_mutex
);
1191 scm_i_thread_go_to_sleep
= 0;
1192 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
1197 scm_i_thread_invalidate_freelists ()
1199 /* Don't need to lock thread_admin_mutex here since we are sinle threaded */
1200 SCM threads
= all_threads
;
1201 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1202 if (SCM_CAR (threads
) != cur_thread
)
1204 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1205 t
->clear_freelists_p
= 1;
1210 scm_i_thread_wake_up ()
1212 if (threads_initialized_p
&& gc_section_count
== 1)
1215 /* Need to lock since woken threads can die and be deleted from list */
1216 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
1217 threads
= all_threads
;
1218 scm_i_plugin_cond_broadcast (&wake_up_cond
);
1219 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1220 if (SCM_CAR (threads
) != cur_thread
)
1222 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1223 scm_i_plugin_mutex_unlock (&t
->heap_mutex
);
1225 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
1227 SCM_REC_CRITICAL_SECTION_END (gc_section
);
1231 scm_i_thread_sleep_for_gc ()
1235 scm_i_plugin_cond_wait (&wake_up_cond
, &t
->heap_mutex
);
1239 /* The mother of all recursive critical sections */
1240 scm_t_mutex scm_i_section_mutex
;
1242 scm_t_mutex scm_i_critical_section_mutex
;
1243 scm_t_mutex scm_i_defer_mutex
;
1244 int scm_i_defer_count
= 0;
1245 scm_thread
*scm_i_defer_owner
= 0;
1247 /*** Initialization */
1250 scm_threads_prehistory ()
1253 scm_i_plugin_mutex_init (&thread_admin_mutex
, 0);
1254 scm_i_plugin_mutex_init (&gc_section_mutex
, 0);
1255 scm_i_plugin_cond_init (&wake_up_cond
, 0);
1256 scm_i_plugin_mutex_init (&scm_i_critical_section_mutex
, 0);
1258 scm_i_plugin_key_create (&scm_i_thread_key
, 0);
1259 scm_i_plugin_key_create (&scm_i_root_state_key
, 0);
1260 scm_i_plugin_mutex_init (&scm_i_defer_mutex
, 0);
1261 scm_i_plugin_mutex_init (&scm_i_section_mutex
, 0);
1262 /* Allocate a fake thread object to be used during bootup. */
1263 t
= malloc (sizeof (scm_thread
));
1265 t
->clear_freelists_p
= 0;
1266 scm_setspecific (scm_i_thread_key
, t
);
1269 scm_t_bits scm_tc16_thread
;
1270 scm_t_bits scm_tc16_mutex
;
1271 scm_t_bits scm_tc16_fair_mutex
;
1272 scm_t_bits scm_tc16_condvar
;
1273 scm_t_bits scm_tc16_fair_condvar
;
1276 scm_init_threads (SCM_STACKITEM
*base
)
1279 scm_tc16_thread
= scm_make_smob_type ("thread", sizeof (scm_thread
));
1280 scm_tc16_mutex
= scm_make_smob_type ("mutex", sizeof (scm_t_mutex
));
1281 scm_tc16_fair_mutex
= scm_make_smob_type ("fair-mutex",
1282 sizeof (fair_mutex
));
1283 scm_tc16_condvar
= scm_make_smob_type ("condition-variable",
1284 sizeof (scm_t_cond
));
1285 scm_tc16_fair_condvar
= scm_make_smob_type ("fair-condition-variable",
1286 sizeof (fair_cond
));
1288 thread
= make_thread (SCM_BOOL_F
);
1289 /* Replace initial fake thread with a real thread object */
1290 free (SCM_CURRENT_THREAD
);
1291 scm_setspecific (scm_i_thread_key
, SCM_THREAD_DATA (thread
));
1292 scm_i_enter_guile (SCM_CURRENT_THREAD
);
1294 /* root is set later from init.c */
1295 init_thread_creatant (thread
, base
);
1297 scm_gc_register_root (&all_threads
);
1298 all_threads
= scm_cons (thread
, SCM_EOL
);
1300 scm_set_smob_mark (scm_tc16_thread
, thread_mark
);
1301 scm_set_smob_print (scm_tc16_thread
, thread_print
);
1302 scm_set_smob_free (scm_tc16_thread
, thread_free
);
1304 scm_set_smob_mark (scm_tc16_fair_mutex
, fair_mutex_mark
);
1306 scm_set_smob_mark (scm_tc16_fair_condvar
, fair_cond_mark
);
1308 threads_initialized_p
= 1;
1312 scm_init_thread_procs ()
1314 #include "libguile/threads.x"