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
);
352 /* We're leaving with heap_mutex still locked. */
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
);
414 scm_i_enter_guile (parent
);
417 err
= scm_i_plugin_thread_create (&th
, 0, launch_thread
, (void *) data
);
420 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
421 all_threads
= scm_delq_x (thread
, all_threads
);
422 ((scm_thread
*) SCM_THREAD_DATA(thread
))->exited
= 1;
424 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
427 /* Return to old dynamic context. */
428 scm_dowinds (old_winds
, - scm_ilength (old_winds
));
433 scm_syserror ("create-thread");
440 SCM_DEFINE (scm_call_with_new_thread
, "call-with-new-thread", 2, 0, 0,
441 (SCM thunk
, SCM handler
),
442 "Evaluate @var{(thunk)} in a new thread, and new dynamic context, "
443 "returning a new thread object representing the thread. "
444 "If an error occurs during evaluation, call error-thunk, passing it an "
445 "error code describing the condition. "
446 "If this happens, the error-thunk is called outside the scope of the new "
447 "root -- it is called in the same dynamic context in which "
448 "with-new-thread was evaluated, but not in the callers thread. "
449 "All the evaluation rules for dynamic roots apply to threads.")
450 #define FUNC_NAME s_scm_call_with_new_thread
452 SCM_ASSERT (SCM_NFALSEP (scm_thunk_p (thunk
)), thunk
, SCM_ARG1
, FUNC_NAME
);
453 SCM_ASSERT (SCM_NFALSEP (scm_procedure_p (handler
)), handler
, SCM_ARG2
,
456 return create_thread ((scm_t_catch_body
) scm_call_0
, thunk
,
457 (scm_t_catch_handler
) scm_apply_1
, handler
,
458 scm_cons (thunk
, handler
));
462 SCM_DEFINE (scm_join_thread
, "join-thread", 1, 0, 0,
464 "Suspend execution of the calling thread until the target @var{thread} "
465 "terminates, unless the target @var{thread} has already terminated. ")
466 #define FUNC_NAME s_scm_join_thread
471 SCM_VALIDATE_THREAD (1, thread
);
472 if (SCM_EQ_P (cur_thread
, thread
))
473 SCM_MISC_ERROR ("can not join the current thread", SCM_EOL
);
475 t
= SCM_THREAD_DATA (thread
);
478 scm_thread
*c
= scm_i_leave_guile ();
479 while (!THREAD_INITIALIZED_P (t
))
481 scm_thread_join (t
->thread
, 0);
482 scm_i_enter_guile (c
);
485 t
->result
= SCM_BOOL_F
;
492 /* We implement our own mutex type since we want them to be 'fair', we
493 want to do fancy things while waiting for them (like running
494 asyncs) and we want to support waiting on many things at once.
495 Also, we might add things that are nice for debugging.
498 typedef struct fair_mutex
{
499 /* the thread currently owning the mutex, or SCM_BOOL_F. */
503 /* how much the owner owns us. */
505 /* the threads waiting for this mutex. */
510 fair_mutex_mark (SCM mx
)
512 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
513 scm_gc_mark (m
->owner
);
517 SCM_DEFINE (scm_make_fair_mutex
, "make-fair-mutex", 0, 0, 0,
519 "Create a new fair mutex object. ")
520 #define FUNC_NAME s_scm_make_fair_mutex
522 SCM mx
= scm_make_smob (scm_tc16_fair_mutex
);
523 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
524 scm_i_plugin_mutex_init (&m
->lock
, 0);
526 m
->owner
= SCM_BOOL_F
;
528 m
->waiting
= make_queue ();
534 fair_mutex_lock (fair_mutex
*m
)
536 scm_i_plugin_mutex_lock (&m
->lock
);
538 /* Need to wait if another thread is just temporarily unlocking.
539 This is happens very seldom and only when the other thread is
540 between scm_mutex_unlock and scm_i_plugin_mutex_lock below. */
546 if (m
->owner
== SCM_BOOL_F
)
547 m
->owner
= cur_thread
;
548 else if (m
->owner
== cur_thread
)
554 SCM c
= enqueue (m
->waiting
, cur_thread
);
556 /* Note: It's important that m->lock is never locked for
557 any longer amount of time since that could prevent GC */
558 scm_i_plugin_mutex_unlock (&m
->lock
);
560 if (m
->owner
== cur_thread
)
562 scm_i_plugin_mutex_lock (&m
->lock
);
563 remqueue (m
->waiting
, c
);
564 scm_i_plugin_mutex_unlock (&m
->lock
);
568 scm_i_plugin_mutex_lock (&m
->lock
);
571 scm_i_plugin_mutex_unlock (&m
->lock
);
576 fair_mutex_trylock (fair_mutex
*m
)
578 scm_i_plugin_mutex_lock (&m
->lock
);
579 if (m
->owner
== SCM_BOOL_F
)
580 m
->owner
= cur_thread
;
581 else if (m
->owner
== cur_thread
)
585 scm_i_plugin_mutex_unlock (&m
->lock
);
588 scm_i_plugin_mutex_unlock (&m
->lock
);
593 fair_mutex_unlock (fair_mutex
*m
)
595 scm_i_plugin_mutex_lock (&m
->lock
);
596 if (m
->owner
!= cur_thread
)
598 scm_i_plugin_mutex_unlock (&m
->lock
);
601 else if (m
->level
> 0)
605 SCM next
= dequeue (m
->waiting
);
606 if (!SCM_FALSEP (next
))
609 unblock (SCM_THREAD_DATA (next
));
612 m
->owner
= SCM_BOOL_F
;
614 scm_i_plugin_mutex_unlock (&m
->lock
);
618 /*** Fair condition variables */
620 /* Like mutexes, we implement our own condition variables using the
624 typedef struct fair_cond
{
626 /* the threads waiting for this condition. */
631 fair_cond_mark (SCM cv
)
633 fair_cond
*c
= SCM_CONDVAR_DATA (cv
);
637 SCM_DEFINE (scm_make_fair_condition_variable
, "make-fair-condition-variable", 0, 0, 0,
639 "Make a new fair condition variable.")
640 #define FUNC_NAME s_scm_make_fair_condition_variable
642 SCM cv
= scm_make_smob (scm_tc16_fair_condvar
);
643 fair_cond
*c
= SCM_CONDVAR_DATA (cv
);
644 scm_i_plugin_mutex_init (&c
->lock
, 0);
645 c
->waiting
= make_queue ();
651 fair_cond_timedwait (fair_cond
*c
,
653 const struct timespec
*waittime
)
656 scm_i_plugin_mutex_lock (&c
->lock
);
660 enqueue (c
->waiting
, cur_thread
);
661 scm_i_plugin_mutex_unlock (&c
->lock
);
662 fair_mutex_unlock (m
); /*fixme* - not thread safe */
663 if (waittime
== NULL
)
666 err
= timed_block (waittime
);
670 /* XXX - check whether we have been signalled. */
677 fair_cond_signal (fair_cond
*c
)
680 scm_i_plugin_mutex_lock (&c
->lock
);
681 if (!SCM_FALSEP (th
= dequeue (c
->waiting
)))
682 unblock (SCM_THREAD_DATA (th
));
683 scm_i_plugin_mutex_unlock (&c
->lock
);
688 fair_cond_broadcast (fair_cond
*c
)
691 scm_i_plugin_mutex_lock (&c
->lock
);
692 while (!SCM_FALSEP (th
= dequeue (c
->waiting
)))
693 unblock (SCM_THREAD_DATA (th
));
694 scm_i_plugin_mutex_unlock (&c
->lock
);
700 SCM_DEFINE (scm_make_mutex
, "make-mutex", 0, 0, 0,
702 "Create a new mutex object. ")
703 #define FUNC_NAME s_scm_make_mutex
705 SCM mx
= scm_make_smob (scm_tc16_mutex
);
706 scm_i_plugin_mutex_init (SCM_MUTEX_DATA (mx
), 0);
711 /*fixme* change documentation */
712 SCM_DEFINE (scm_lock_mutex
, "lock-mutex", 1, 0, 0,
714 "Lock @var{mutex}. If the mutex is already locked, the calling thread "
715 "blocks until the mutex becomes available. The function returns when "
716 "the calling thread owns the lock on @var{mutex}. Locking a mutex that "
717 "a thread already owns will succeed right away and will not block the "
718 "thread. That is, Guile's mutexes are @emph{recursive}. ")
719 #define FUNC_NAME s_scm_lock_mutex
722 SCM_VALIDATE_MUTEX (1, mx
);
724 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
725 err
= fair_mutex_lock (SCM_MUTEX_DATA (mx
));
728 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
729 scm_thread
*t
= scm_i_leave_guile ();
730 err
= scm_i_plugin_mutex_lock (m
);
731 scm_i_enter_guile (t
);
743 SCM_DEFINE (scm_try_mutex
, "try-mutex", 1, 0, 0,
745 "Try to lock @var{mutex}. If the mutex is already locked by someone "
746 "else, return @code{#f}. Else lock the mutex and return @code{#t}. ")
747 #define FUNC_NAME s_scm_try_mutex
750 SCM_VALIDATE_MUTEX (1, mx
);
752 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
753 err
= fair_mutex_trylock (SCM_MUTEX_DATA (mx
));
756 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
757 scm_thread
*t
= scm_i_leave_guile ();
758 err
= scm_i_plugin_mutex_trylock (m
);
759 scm_i_enter_guile (t
);
775 SCM_DEFINE (scm_unlock_mutex
, "unlock-mutex", 1, 0, 0,
777 "Unlocks @var{mutex} if the calling thread owns the lock on "
778 "@var{mutex}. Calling unlock-mutex on a mutex not owned by the current "
779 "thread results in undefined behaviour. Once a mutex has been unlocked, "
780 "one thread blocked on @var{mutex} is awakened and grabs the mutex "
781 "lock. Every call to @code{lock-mutex} by this thread must be matched "
782 "with a call to @code{unlock-mutex}. Only the last call to "
783 "@code{unlock-mutex} will actually unlock the mutex. ")
784 #define FUNC_NAME s_scm_unlock_mutex
787 SCM_VALIDATE_MUTEX (1, mx
);
789 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
791 err
= fair_mutex_unlock (SCM_MUTEX_DATA (mx
));
794 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
795 if (m
->owner
!= cur_thread
)
797 if (m
->owner
== SCM_BOOL_F
)
798 SCM_MISC_ERROR ("mutex not locked", SCM_EOL
);
800 SCM_MISC_ERROR ("mutex not locked by this thread", SCM_EOL
);
806 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
807 err
= scm_i_plugin_mutex_unlock (m
);
819 /*** Condition variables */
821 SCM_DEFINE (scm_make_condition_variable
, "make-condition-variable", 0, 0, 0,
823 "Make a new condition variable.")
824 #define FUNC_NAME s_scm_make_condition_variable
826 SCM cv
= scm_make_smob (scm_tc16_condvar
);
827 scm_i_plugin_cond_init (SCM_CONDVAR_DATA (cv
), 0);
832 SCM_DEFINE (scm_timed_wait_condition_variable
, "wait-condition-variable", 2, 1, 0,
833 (SCM cv
, SCM mx
, SCM t
),
834 "Wait until @var{cond-var} has been signalled. While waiting, "
835 "@var{mutex} is atomically unlocked (as with @code{unlock-mutex}) and "
836 "is locked again when this function returns. When @var{time} is given, "
837 "it specifies a point in time where the waiting should be aborted. It "
838 "can be either a integer as returned by @code{current-time} or a pair "
839 "as returned by @code{gettimeofday}. When the waiting is aborted the "
840 "mutex is locked and @code{#f} is returned. When the condition "
841 "variable is in fact signalled, the mutex is also locked and @code{#t} "
843 #define FUNC_NAME s_scm_timed_wait_condition_variable
845 struct timespec waittime
;
848 SCM_VALIDATE_CONDVAR (1, cv
);
849 SCM_VALIDATE_MUTEX (2, mx
);
850 if (!((SCM_TYP16 (cv
) == scm_tc16_condvar
851 && SCM_TYP16 (mx
) == scm_tc16_mutex
)
852 || (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
853 && SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)))
854 SCM_MISC_ERROR ("Condition variable and mutex are of different kinds.",
861 SCM_VALIDATE_UINT_COPY (3, SCM_CAR (t
), waittime
.tv_sec
);
862 SCM_VALIDATE_UINT_COPY (3, SCM_CDR (t
), waittime
.tv_nsec
);
863 waittime
.tv_nsec
*= 1000;
867 SCM_VALIDATE_UINT_COPY (3, t
, waittime
.tv_sec
);
868 waittime
.tv_nsec
= 0;
872 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
873 err
= fair_cond_timedwait (SCM_CONDVAR_DATA (cv
),
875 SCM_UNBNDP (t
) ? NULL
: &waittime
);
878 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
879 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
880 scm_thread
*t
= scm_i_leave_guile ();
881 err
= scm_i_plugin_cond_wait (c
, m
);
882 scm_i_enter_guile (t
);
894 SCM_DEFINE (scm_signal_condition_variable
, "signal-condition-variable", 1, 0, 0,
896 "Wake up one thread that is waiting for @var{cv}")
897 #define FUNC_NAME s_scm_signal_condition_variable
899 SCM_VALIDATE_CONDVAR (1, cv
);
900 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
901 fair_cond_signal (SCM_CONDVAR_DATA (cv
));
904 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
905 scm_i_plugin_cond_signal (c
);
911 SCM_DEFINE (scm_broadcast_condition_variable
, "broadcast-condition-variable", 1, 0, 0,
913 "Wake up all threads that are waiting for @var{cv}. ")
914 #define FUNC_NAME s_scm_broadcast_condition_variable
916 SCM_VALIDATE_CONDVAR (1, cv
);
917 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
918 fair_cond_broadcast (SCM_CONDVAR_DATA (cv
));
921 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
922 scm_i_plugin_cond_broadcast (c
);
928 /*** Marking stacks */
930 /* XXX - what to do with this? Do we need to handle this for blocked
934 # define SCM_MARK_BACKING_STORE() do { \
936 SCM_STACKITEM * top, * bot; \
938 scm_mark_locations ((SCM_STACKITEM *) &ctx.uc_mcontext, \
939 ((size_t) (sizeof (SCM_STACKITEM) - 1 + sizeof ctx.uc_mcontext) \
940 / sizeof (SCM_STACKITEM))); \
941 bot = (SCM_STACKITEM *) __libc_ia64_register_backing_store_base; \
942 top = (SCM_STACKITEM *) ctx.uc_mcontext.sc_ar_bsp; \
943 scm_mark_locations (bot, top - bot); } while (0)
945 # define SCM_MARK_BACKING_STORE()
949 scm_threads_mark_stacks (void)
952 for (c
= all_threads
; !SCM_NULLP (c
); c
= SCM_CDR (c
))
954 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (c
));
955 if (!THREAD_INITIALIZED_P (t
))
957 /* Not fully initialized yet. */
964 if (t
->thread
!= scm_thread_self ())
968 /* stack_len is long rather than sizet in order to guarantee
969 that &stack_len is long aligned */
970 #ifdef STACK_GROWS_UP
971 stack_len
= ((SCM_STACKITEM
*) (&t
) -
972 (SCM_STACKITEM
*) thread
->base
);
974 /* Protect from the C stack. This must be the first marking
975 * done because it provides information about what objects
976 * are "in-use" by the C code. "in-use" objects are those
977 * for which the information about length and base address must
978 * remain usable. This requirement is stricter than a liveness
979 * requirement -- in particular, it constrains the implementation
982 SCM_FLUSH_REGISTER_WINDOWS
;
983 /* This assumes that all registers are saved into the jmp_buf */
984 setjmp (scm_save_regs_gc_mark
);
985 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
986 ((size_t) sizeof scm_save_regs_gc_mark
987 / sizeof (SCM_STACKITEM
)));
989 scm_mark_locations (((size_t) t
->base
,
992 stack_len
= ((SCM_STACKITEM
*) t
->base
-
993 (SCM_STACKITEM
*) (&t
));
995 /* Protect from the C stack. This must be the first marking
996 * done because it provides information about what objects
997 * are "in-use" by the C code. "in-use" objects are those
998 * for which the information about length and base address must
999 * remain usable. This requirement is stricter than a liveness
1000 * requirement -- in particular, it constrains the implementation
1003 SCM_FLUSH_REGISTER_WINDOWS
;
1004 /* This assumes that all registers are saved into the jmp_buf */
1005 setjmp (scm_save_regs_gc_mark
);
1006 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
1007 ((size_t) sizeof scm_save_regs_gc_mark
1008 / sizeof (SCM_STACKITEM
)));
1010 scm_mark_locations ((SCM_STACKITEM
*) &t
,
1016 /* Suspended thread */
1017 #ifdef STACK_GROWS_UP
1018 long stack_len
= t
->top
- t
->base
;
1019 scm_mark_locations (t
->base
, stack_len
);
1021 long stack_len
= t
->base
- t
->top
;
1022 scm_mark_locations (t
->top
, stack_len
);
1024 scm_mark_locations ((SCM_STACKITEM
*) t
->regs
,
1025 ((size_t) sizeof(t
->regs
)
1026 / sizeof (SCM_STACKITEM
)));
1034 scm_internal_select (int nfds
,
1035 SELECT_TYPE
*readfds
,
1036 SELECT_TYPE
*writefds
,
1037 SELECT_TYPE
*exceptfds
,
1038 struct timeval
*timeout
)
1041 scm_thread
*c
= scm_i_leave_guile ();
1042 res
= scm_i_plugin_select (nfds
, readfds
, writefds
, exceptfds
, timeout
);
1044 scm_i_enter_guile (c
);
1050 /* Low-level C API */
1053 scm_spawn_thread (scm_t_catch_body body
, void *body_data
,
1054 scm_t_catch_handler handler
, void *handler_data
)
1056 return create_thread (body
, body_data
, handler
, handler_data
, SCM_BOOL_F
);
1060 scm_mutex_lock (scm_t_mutex
*m
)
1062 scm_thread
*t
= scm_i_leave_guile ();
1063 int res
= scm_i_plugin_mutex_lock (m
);
1064 scm_i_enter_guile (t
);
1069 scm_cond_wait (scm_t_cond
*c
, scm_t_mutex
*m
)
1071 scm_thread
*t
= scm_i_leave_guile ();
1072 scm_i_plugin_cond_wait (c
, m
);
1073 scm_i_enter_guile (t
);
1078 scm_cond_timedwait (scm_t_cond
*c
, scm_t_mutex
*m
, const struct timespec
*wt
)
1080 scm_thread
*t
= scm_i_leave_guile ();
1081 int res
= scm_i_plugin_cond_timedwait (c
, m
, wt
);
1082 scm_i_enter_guile (t
);
1089 scm_i_enter_guile (SCM_CURRENT_THREAD
);
1095 scm_i_leave_guile ();
1099 scm_thread_usleep (unsigned long usecs
)
1102 tv
.tv_usec
= usecs
% 1000000;
1103 tv
.tv_sec
= usecs
/ 1000000;
1104 scm_internal_select (0, NULL
, NULL
, NULL
, &tv
);
1105 return tv
.tv_usec
+ tv
.tv_sec
*1000000;
1109 scm_thread_sleep (unsigned long secs
)
1114 scm_internal_select (0, NULL
, NULL
, NULL
, &tv
);
1120 SCM_DEFINE (scm_current_thread
, "current-thread", 0, 0, 0,
1122 "Return the thread that called this function.")
1123 #define FUNC_NAME s_scm_current_thread
1129 SCM_DEFINE (scm_all_threads
, "all-threads", 0, 0, 0,
1131 "Return a list of all threads.")
1132 #define FUNC_NAME s_scm_all_threads
1139 scm_i_thread_root (SCM thread
)
1141 return ((scm_thread
*) SCM_THREAD_DATA (thread
))->root
;
1144 SCM_DEFINE (scm_thread_exited_p
, "thread-exited?", 1, 0, 0,
1146 "Return @code{#t} iff @var{thread} has exited.\n")
1147 #define FUNC_NAME s_scm_thread_exited_p
1149 return SCM_BOOL (scm_c_thread_exited_p (thread
));
1154 scm_c_thread_exited_p (SCM thread
)
1155 #define FUNC_NAME s_scm_thread_exited_p
1158 SCM_VALIDATE_THREAD (1, thread
);
1159 t
= SCM_THREAD_DATA (thread
);
1164 static scm_t_cond wake_up_cond
;
1165 int scm_i_thread_go_to_sleep
;
1166 static scm_t_mutex gc_section_mutex
;
1167 static scm_thread
*gc_section_owner
;
1168 static int gc_section_count
= 0;
1169 static int threads_initialized_p
= 0;
1172 scm_i_thread_put_to_sleep ()
1174 SCM_REC_CRITICAL_SECTION_START (gc_section
);
1175 if (threads_initialized_p
&& gc_section_count
== 1)
1178 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
1179 threads
= all_threads
;
1180 /* Signal all threads to go to sleep */
1181 scm_i_thread_go_to_sleep
= 1;
1182 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1183 if (SCM_CAR (threads
) != cur_thread
)
1185 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1186 scm_i_plugin_mutex_lock (&t
->heap_mutex
);
1188 scm_i_thread_go_to_sleep
= 0;
1189 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
1194 scm_i_thread_invalidate_freelists ()
1196 /* Don't need to lock thread_admin_mutex here since we are sinle threaded */
1197 SCM threads
= all_threads
;
1198 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1199 if (SCM_CAR (threads
) != cur_thread
)
1201 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1202 t
->clear_freelists_p
= 1;
1207 scm_i_thread_wake_up ()
1209 if (threads_initialized_p
&& gc_section_count
== 1)
1212 /* Need to lock since woken threads can die and be deleted from list */
1213 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
1214 threads
= all_threads
;
1215 scm_i_plugin_cond_broadcast (&wake_up_cond
);
1216 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1217 if (SCM_CAR (threads
) != cur_thread
)
1219 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1220 scm_i_plugin_mutex_unlock (&t
->heap_mutex
);
1222 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
1224 SCM_REC_CRITICAL_SECTION_END (gc_section
);
1228 scm_i_thread_sleep_for_gc ()
1232 scm_i_plugin_cond_wait (&wake_up_cond
, &t
->heap_mutex
);
1236 /* The mother of all recursive critical sections */
1237 scm_t_mutex scm_i_section_mutex
;
1239 scm_t_mutex scm_i_critical_section_mutex
;
1240 scm_t_mutex scm_i_defer_mutex
;
1241 int scm_i_defer_count
= 0;
1242 scm_thread
*scm_i_defer_owner
= 0;
1244 /*** Initialization */
1247 scm_threads_prehistory ()
1250 scm_i_plugin_mutex_init (&thread_admin_mutex
, 0);
1251 scm_i_plugin_mutex_init (&gc_section_mutex
, 0);
1252 scm_i_plugin_cond_init (&wake_up_cond
, 0);
1253 scm_i_plugin_mutex_init (&scm_i_critical_section_mutex
, 0);
1255 scm_i_plugin_key_create (&scm_i_thread_key
, 0);
1256 scm_i_plugin_key_create (&scm_i_root_state_key
, 0);
1257 scm_i_plugin_mutex_init (&scm_i_defer_mutex
, 0);
1258 scm_i_plugin_mutex_init (&scm_i_section_mutex
, 0);
1259 /* Allocate a fake thread object to be used during bootup. */
1260 t
= malloc (sizeof (scm_thread
));
1262 t
->clear_freelists_p
= 0;
1263 scm_setspecific (scm_i_thread_key
, t
);
1266 scm_t_bits scm_tc16_thread
;
1267 scm_t_bits scm_tc16_mutex
;
1268 scm_t_bits scm_tc16_fair_mutex
;
1269 scm_t_bits scm_tc16_condvar
;
1270 scm_t_bits scm_tc16_fair_condvar
;
1273 scm_init_threads (SCM_STACKITEM
*base
)
1276 scm_tc16_thread
= scm_make_smob_type ("thread", sizeof (scm_thread
));
1277 scm_tc16_mutex
= scm_make_smob_type ("mutex", sizeof (scm_t_mutex
));
1278 scm_tc16_fair_mutex
= scm_make_smob_type ("fair-mutex",
1279 sizeof (fair_mutex
));
1280 scm_tc16_condvar
= scm_make_smob_type ("condition-variable",
1281 sizeof (scm_t_cond
));
1282 scm_tc16_fair_condvar
= scm_make_smob_type ("fair-condition-variable",
1283 sizeof (fair_cond
));
1285 thread
= make_thread (SCM_BOOL_F
);
1286 /* Replace initial fake thread with a real thread object */
1287 free (SCM_CURRENT_THREAD
);
1288 scm_setspecific (scm_i_thread_key
, SCM_THREAD_DATA (thread
));
1289 scm_i_enter_guile (SCM_CURRENT_THREAD
);
1291 /* root is set later from init.c */
1292 init_thread_creatant (thread
, base
);
1294 scm_gc_register_root (&all_threads
);
1295 all_threads
= scm_cons (thread
, SCM_EOL
);
1297 scm_set_smob_mark (scm_tc16_thread
, thread_mark
);
1298 scm_set_smob_print (scm_tc16_thread
, thread_print
);
1299 scm_set_smob_free (scm_tc16_thread
, thread_free
);
1301 scm_set_smob_mark (scm_tc16_fair_mutex
, fair_mutex_mark
);
1303 scm_set_smob_mark (scm_tc16_fair_condvar
, fair_cond_mark
);
1305 threads_initialized_p
= 1;
1309 scm_init_thread_procs ()
1311 #include "libguile/threads.x"