2 * This software is part of the SBCL system. See the README file for
5 * This software is derived from the CMU CL system, which was
6 * written at Carnegie Mellon University and released into the
7 * public domain. The software is in the public domain and is
8 * provided with absolutely no warranty. See the COPYING and CREDITS
9 * files for more information.
17 #ifndef LISP_FEATURE_WIN32
23 #include <sys/types.h>
24 #ifndef LISP_FEATURE_WIN32
28 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
29 #include <mach/mach.h>
30 #include <mach/mach_error.h>
31 #include <mach/mach_types.h>
35 #include "validate.h" /* for CONTROL_STACK_SIZE etc */
39 #include "target-arch-os.h"
43 #include "genesis/cons.h"
44 #include "genesis/fdefn.h"
45 #include "interr.h" /* for lose() */
46 #include "gc-internal.h"
48 #ifdef LISP_FEATURE_WIN32
50 * Win32 doesn't have SIGSTKSZ, and we're not switching stacks anyway,
51 * so define it arbitrarily
56 #if defined(LISP_FEATURE_DARWIN) && defined(LISP_FEATURE_SB_THREAD)
57 #define QUEUE_FREEABLE_THREAD_STACKS
58 #define LOCK_CREATE_THREAD
61 #ifdef LISP_FEATURE_FREEBSD
62 #define CREATE_CLEANUP_THREAD
63 #define LOCK_CREATE_THREAD
66 #define ALIEN_STACK_SIZE (1*1024*1024) /* 1Mb size chosen at random */
68 struct freeable_stack
{
69 #ifdef QUEUE_FREEABLE_THREAD_STACKS
70 struct freeable_stack
*next
;
72 os_thread_t os_thread
;
73 os_vm_address_t os_address
;
77 #ifdef QUEUE_FREEABLE_THREAD_STACKS
78 static struct freeable_stack
* volatile freeable_stack_queue
= 0;
79 static int freeable_stack_count
= 0;
80 pthread_mutex_t freeable_stack_lock
= PTHREAD_MUTEX_INITIALIZER
;
82 static struct freeable_stack
* volatile freeable_stack
= 0;
85 int dynamic_values_bytes
=4096*sizeof(lispobj
); /* same for all threads */
86 struct thread
* volatile all_threads
;
87 extern struct interrupt_data
* global_interrupt_data
;
89 #ifdef LISP_FEATURE_SB_THREAD
90 pthread_mutex_t all_threads_lock
= PTHREAD_MUTEX_INITIALIZER
;
91 #ifdef LOCK_CREATE_THREAD
92 static pthread_mutex_t create_thread_lock
= PTHREAD_MUTEX_INITIALIZER
;
96 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
97 extern lispobj
call_into_lisp_first_time(lispobj fun
, lispobj
*args
, int nargs
);
101 link_thread(struct thread
*th
)
103 if (all_threads
) all_threads
->prev
=th
;
104 th
->next
=all_threads
;
109 #ifdef LISP_FEATURE_SB_THREAD
111 unlink_thread(struct thread
*th
)
114 th
->prev
->next
= th
->next
;
116 all_threads
= th
->next
;
118 th
->next
->prev
= th
->prev
;
123 initial_thread_trampoline(struct thread
*th
)
126 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
127 lispobj
*args
= NULL
;
129 function
= th
->no_tls_value_marker
;
130 th
->no_tls_value_marker
= NO_TLS_VALUE_MARKER_WIDETAG
;
131 if(arch_os_thread_init(th
)==0) return 1;
133 th
->os_thread
=thread_self();
134 #ifndef LISP_FEATURE_WIN32
135 protect_control_stack_guard_page(1);
138 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
139 return call_into_lisp_first_time(function
,args
,0);
141 return funcall0(function
);
145 #define THREAD_STRUCT_SIZE (THREAD_CONTROL_STACK_SIZE + BINDING_STACK_SIZE + \
146 ALIEN_STACK_SIZE + dynamic_values_bytes + \
150 #ifdef LISP_FEATURE_SB_THREAD
152 #ifdef QUEUE_FREEABLE_THREAD_STACKS
155 queue_freeable_thread_stack(struct thread
*thread_to_be_cleaned_up
)
157 struct freeable_stack
*new_freeable_stack
= 0;
158 if (thread_to_be_cleaned_up
) {
159 /* FIXME: os_validate is mmap -- for small things like these
160 * malloc would probably perform better. */
161 new_freeable_stack
= (struct freeable_stack
*)
162 os_validate(0, sizeof(struct freeable_stack
));
163 new_freeable_stack
->next
= NULL
;
164 new_freeable_stack
->os_thread
= thread_to_be_cleaned_up
->os_thread
;
165 new_freeable_stack
->os_address
= thread_to_be_cleaned_up
->os_address
;
166 pthread_mutex_lock(&freeable_stack_lock
);
167 if (freeable_stack_queue
) {
168 struct freeable_stack
*next
;
169 next
= freeable_stack_queue
;
173 next
->next
= new_freeable_stack
;
175 freeable_stack_queue
= new_freeable_stack
;
177 freeable_stack_count
++;
178 pthread_mutex_unlock(&freeable_stack_lock
);
182 #define FREEABLE_STACK_QUEUE_SIZE 4
185 free_freeable_stacks() {
186 if (freeable_stack_queue
&& (freeable_stack_count
> FREEABLE_STACK_QUEUE_SIZE
)) {
187 struct freeable_stack
* old
;
188 pthread_mutex_lock(&freeable_stack_lock
);
189 old
= freeable_stack_queue
;
190 freeable_stack_queue
= old
->next
;
191 freeable_stack_count
--;
192 gc_assert(pthread_join(old
->os_thread
, NULL
) == 0);
193 FSHOW((stderr
, "freeing thread %x stack\n", old
->os_thread
));
194 os_invalidate(old
->os_address
, THREAD_STRUCT_SIZE
);
195 os_invalidate((os_vm_address_t
)old
, sizeof(struct freeable_stack
));
196 pthread_mutex_unlock(&freeable_stack_lock
);
200 #elif defined(CREATE_CLEANUP_THREAD)
202 cleanup_thread(void *arg
)
204 struct freeable_stack
*freeable
= arg
;
205 pthread_t self
= pthread_self();
207 FSHOW((stderr
, "/cleaner thread(%p): joining %p\n",
208 self
, freeable
->os_thread
));
209 gc_assert(pthread_join(freeable
->os_thread
, NULL
) == 0);
210 FSHOW((stderr
, "/cleaner thread(%p): free stack %p\n",
211 self
, freeable
->stack
));
212 os_invalidate(freeable
->os_address
, THREAD_STRUCT_SIZE
);
215 pthread_detach(self
);
221 create_cleanup_thread(struct thread
*thread_to_be_cleaned_up
)
226 if (thread_to_be_cleaned_up
) {
227 struct freeable_stack
*freeable
=
228 malloc(sizeof(struct freeable_stack
));
229 gc_assert(freeable
!= NULL
);
230 freeable
->os_thread
= thread_to_be_cleaned_up
->os_thread
;
231 freeable
->os_address
=
232 (os_vm_address_t
) thread_to_be_cleaned_up
->os_address
;
233 result
= pthread_create(&thread
, NULL
, cleanup_thread
, freeable
);
234 gc_assert(result
== 0);
241 free_thread_stack_later(struct thread
*thread_to_be_cleaned_up
)
243 struct freeable_stack
*new_freeable_stack
= 0;
244 if (thread_to_be_cleaned_up
) {
245 new_freeable_stack
= (struct freeable_stack
*)
246 os_validate(0, sizeof(struct freeable_stack
));
247 new_freeable_stack
->os_thread
= thread_to_be_cleaned_up
->os_thread
;
248 new_freeable_stack
->os_address
= (os_vm_address_t
)
249 thread_to_be_cleaned_up
->os_address
;
251 new_freeable_stack
= (struct freeable_stack
*)
252 swap_lispobjs((lispobj
*)(void *)&freeable_stack
,
253 (lispobj
)new_freeable_stack
);
254 if (new_freeable_stack
) {
255 FSHOW((stderr
,"/reaping %p\n", (void*) new_freeable_stack
->os_thread
));
256 /* Under NPTL pthread_join really waits until the thread
257 * exists and the stack can be safely freed. This is sadly not
258 * mandated by the pthread spec. */
259 gc_assert(pthread_join(new_freeable_stack
->os_thread
, NULL
) == 0);
260 os_invalidate(new_freeable_stack
->os_address
, THREAD_STRUCT_SIZE
);
261 os_invalidate((os_vm_address_t
) new_freeable_stack
,
262 sizeof(struct freeable_stack
));
267 /* this is the first thing that runs in the child (which is why the
268 * silly calling convention). Basically it calls the user's requested
269 * lisp function after doing arch_os_thread_init and whatever other
270 * bookkeeping needs to be done
273 new_thread_trampoline(struct thread
*th
)
276 int result
, lock_ret
;
278 FSHOW((stderr
,"/creating thread %lu\n", thread_self()));
279 function
= th
->no_tls_value_marker
;
280 th
->no_tls_value_marker
= NO_TLS_VALUE_MARKER_WIDETAG
;
281 if(arch_os_thread_init(th
)==0) {
282 /* FIXME: handle error */
283 lose("arch_os_thread_init failed\n");
286 th
->os_thread
=thread_self();
287 protect_control_stack_guard_page(1);
288 /* Since GC can only know about this thread from the all_threads
289 * list and we're just adding this thread to it there is no danger
290 * of deadlocking even with SIG_STOP_FOR_GC blocked (which it is
292 lock_ret
= pthread_mutex_lock(&all_threads_lock
);
293 gc_assert(lock_ret
== 0);
295 lock_ret
= pthread_mutex_unlock(&all_threads_lock
);
296 gc_assert(lock_ret
== 0);
298 result
= funcall0(function
);
301 block_blockable_signals();
302 th
->state
=STATE_DEAD
;
304 /* SIG_STOP_FOR_GC is blocked and GC might be waiting for this
305 * thread, but since we are already dead it won't wait long. */
306 lock_ret
= pthread_mutex_lock(&all_threads_lock
);
307 gc_assert(lock_ret
== 0);
309 gc_alloc_update_page_tables(0, &th
->alloc_region
);
311 pthread_mutex_unlock(&all_threads_lock
);
312 gc_assert(lock_ret
== 0);
314 if(th
->tls_cookie
>=0) arch_os_thread_cleanup(th
);
315 os_invalidate((os_vm_address_t
)th
->interrupt_data
,
316 (sizeof (struct interrupt_data
)));
318 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
319 FSHOW((stderr
, "Deallocating mach port %x\n", THREAD_STRUCT_TO_EXCEPTION_PORT(th
)));
320 mach_port_move_member(mach_task_self(),
321 THREAD_STRUCT_TO_EXCEPTION_PORT(th
),
323 mach_port_deallocate(mach_task_self(),
324 THREAD_STRUCT_TO_EXCEPTION_PORT(th
));
325 mach_port_destroy(mach_task_self(),
326 THREAD_STRUCT_TO_EXCEPTION_PORT(th
));
329 #ifdef QUEUE_FREEABLE_THREAD_STACKS
330 queue_freeable_thread_stack(th
);
331 #elif defined(CREATE_CLEANUP_THREAD)
332 create_cleanup_thread(th
);
334 free_thread_stack_later(th
);
337 FSHOW((stderr
,"/exiting thread %p\n", thread_self()));
341 #endif /* LISP_FEATURE_SB_THREAD */
344 free_thread_struct(struct thread
*th
)
346 if (th
->interrupt_data
)
347 os_invalidate((os_vm_address_t
) th
->interrupt_data
,
348 (sizeof (struct interrupt_data
)));
349 os_invalidate((os_vm_address_t
) th
->os_address
,
353 /* this is called from any other thread to create the new one, and
354 * initialize all parts of it that can be initialized from another
358 static struct thread
*
359 create_thread_struct(lispobj initial_function
) {
360 union per_thread_data
*per_thread
;
361 struct thread
*th
=0; /* subdue gcc */
363 void *aligned_spaces
=0;
364 #ifdef LISP_FEATURE_SB_THREAD
368 #ifdef CREATE_CLEANUP_THREAD
369 /* Give a chance for cleanup threads to run. */
372 /* May as well allocate all the spaces at once: it saves us from
373 * having to decide what to do if only some of the allocations
374 * succeed. SPACES must be page-aligned, since the GC expects the
375 * control stack to start at a page boundary. We can't rely on the
376 * alignment passed from os_validate, since that might assume the
377 * current (e.g. 4k) pagesize, while we calculate with the biggest
378 * (e.g. 64k) pagesize allowed by the ABI. */
379 spaces
=os_validate(0, THREAD_STRUCT_SIZE
);
382 /* Aligning up is safe as THREAD_STRUCT_SIZE has BACKEND_PAGE_SIZE
384 aligned_spaces
= (void *)((((unsigned long)(char *)spaces
)
385 + BACKEND_PAGE_SIZE
- 1)
386 & ~(unsigned long)(BACKEND_PAGE_SIZE
- 1));
387 per_thread
=(union per_thread_data
*)
389 THREAD_CONTROL_STACK_SIZE
+
393 #ifdef LISP_FEATURE_SB_THREAD
394 for(i
= 0; i
< (dynamic_values_bytes
/ sizeof(lispobj
)); i
++)
395 per_thread
->dynamic_values
[i
] = NO_TLS_VALUE_MARKER_WIDETAG
;
396 if (all_threads
== 0) {
397 if(SymbolValue(FREE_TLS_INDEX
,0)==UNBOUND_MARKER_WIDETAG
) {
400 /* FIXME: should be MAX_INTERRUPTS -1 ? */
401 make_fixnum(MAX_INTERRUPTS
+
402 sizeof(struct thread
)/sizeof(lispobj
)),
404 SetSymbolValue(TLS_INDEX_LOCK
,make_fixnum(0),0);
406 #define STATIC_TLS_INIT(sym,field) \
407 ((struct symbol *)(sym-OTHER_POINTER_LOWTAG))->tls_index= \
408 make_fixnum(THREAD_SLOT_OFFSET_WORDS(field))
410 STATIC_TLS_INIT(BINDING_STACK_START
,binding_stack_start
);
411 STATIC_TLS_INIT(BINDING_STACK_POINTER
,binding_stack_pointer
);
412 STATIC_TLS_INIT(CONTROL_STACK_START
,control_stack_start
);
413 STATIC_TLS_INIT(CONTROL_STACK_END
,control_stack_end
);
414 STATIC_TLS_INIT(ALIEN_STACK
,alien_stack_pointer
);
415 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
416 STATIC_TLS_INIT(PSEUDO_ATOMIC_BITS
,pseudo_atomic_bits
);
418 #undef STATIC_TLS_INIT
422 th
=&per_thread
->thread
;
423 th
->os_address
= spaces
;
424 th
->control_stack_start
= aligned_spaces
;
425 th
->binding_stack_start
=
426 (lispobj
*)((void*)th
->control_stack_start
+THREAD_CONTROL_STACK_SIZE
);
427 th
->control_stack_end
= th
->binding_stack_start
;
428 th
->alien_stack_start
=
429 (lispobj
*)((void*)th
->binding_stack_start
+BINDING_STACK_SIZE
);
430 th
->binding_stack_pointer
=th
->binding_stack_start
;
433 th
->state
=STATE_RUNNING
;
434 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
435 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
436 + ALIEN_STACK_SIZE
-N_WORD_BYTES
);
438 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
);
440 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
441 th
->pseudo_atomic_bits
=0;
443 #ifdef LISP_FEATURE_GENCGC
444 gc_set_region_empty(&th
->alloc_region
);
447 #ifndef LISP_FEATURE_SB_THREAD
448 /* the tls-points-into-struct-thread trick is only good for threaded
449 * sbcl, because unithread sbcl doesn't have tls. So, we copy the
450 * appropriate values from struct thread here, and make sure that
451 * we use the appropriate SymbolValue macros to access any of the
452 * variable quantities from the C runtime. It's not quite OAOOM,
453 * it just feels like it */
454 SetSymbolValue(BINDING_STACK_START
,(lispobj
)th
->binding_stack_start
,th
);
455 SetSymbolValue(CONTROL_STACK_START
,(lispobj
)th
->control_stack_start
,th
);
456 SetSymbolValue(CONTROL_STACK_END
,(lispobj
)th
->control_stack_end
,th
);
457 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
458 SetSymbolValue(BINDING_STACK_POINTER
,(lispobj
)th
->binding_stack_pointer
,th
);
459 SetSymbolValue(ALIEN_STACK
,(lispobj
)th
->alien_stack_pointer
,th
);
460 SetSymbolValue(PSEUDO_ATOMIC_BITS
,(lispobj
)th
->pseudo_atomic_bits
,th
);
462 current_binding_stack_pointer
=th
->binding_stack_pointer
;
463 current_control_stack_pointer
=th
->control_stack_start
;
466 bind_variable(CURRENT_CATCH_BLOCK
,make_fixnum(0),th
);
467 bind_variable(CURRENT_UNWIND_PROTECT_BLOCK
,make_fixnum(0),th
);
468 bind_variable(FREE_INTERRUPT_CONTEXT_INDEX
,make_fixnum(0),th
);
469 bind_variable(INTERRUPT_PENDING
, NIL
,th
);
470 bind_variable(INTERRUPTS_ENABLED
,T
,th
);
471 bind_variable(ALLOW_WITH_INTERRUPTS
,T
,th
);
472 bind_variable(GC_PENDING
,NIL
,th
);
473 #ifdef LISP_FEATURE_SB_THREAD
474 bind_variable(STOP_FOR_GC_PENDING
,NIL
,th
);
477 th
->interrupt_data
= (struct interrupt_data
*)
478 os_validate(0,(sizeof (struct interrupt_data
)));
479 if (!th
->interrupt_data
) {
480 free_thread_struct(th
);
483 th
->interrupt_data
->pending_handler
= 0;
484 th
->no_tls_value_marker
=initial_function
;
490 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
491 mach_port_t
setup_mach_exception_handling_thread();
492 kern_return_t
mach_thread_init(mach_port_t thread_exception_port
);
496 void create_initial_thread(lispobj initial_function
) {
497 struct thread
*th
=create_thread_struct(initial_function
);
499 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
502 setup_mach_exception_handling_thread();
504 initial_thread_trampoline(th
); /* no return */
505 } else lose("can't create initial thread\n");
508 #ifdef LISP_FEATURE_SB_THREAD
510 #ifndef __USE_XOPEN2K
511 extern int pthread_attr_setstack (pthread_attr_t
*__attr
, void *__stackaddr
,
515 boolean
create_os_thread(struct thread
*th
,os_thread_t
*kid_tid
)
517 /* The new thread inherits the restrictive signal mask set here,
518 * and enables signals again when it is set up properly. */
520 sigset_t newset
,oldset
;
522 int retcode
, initcode
, sizecode
, addrcode
;
524 FSHOW_SIGNAL((stderr
,"/create_os_thread: creating new thread\n"));
526 #ifdef LOCK_CREATE_THREAD
527 retcode
= pthread_mutex_lock(&create_thread_lock
);
528 gc_assert(retcode
== 0);
529 FSHOW_SIGNAL((stderr
,"/create_os_thread: got lock\n"));
531 sigemptyset(&newset
);
532 /* Blocking deferrable signals is enough, no need to block
533 * SIG_STOP_FOR_GC because the child process is not linked onto
534 * all_threads until it's ready. */
535 sigaddset_deferrable(&newset
);
536 thread_sigmask(SIG_BLOCK
, &newset
, &oldset
);
538 #if defined(LISP_FEATURE_DARWIN)
539 #define CONTROL_STACK_ADJUST 8192 /* darwin wants page-aligned stacks */
541 #define CONTROL_STACK_ADJUST 16
544 if((initcode
= pthread_attr_init(&attr
)) ||
545 /* FIXME: why do we even have this in the first place? */
546 (pthread_attr_setstack(&attr
,th
->control_stack_start
,
547 THREAD_CONTROL_STACK_SIZE
-CONTROL_STACK_ADJUST
)) ||
548 #undef CONTROL_STACK_ADJUST
549 (retcode
= pthread_create
550 (kid_tid
,&attr
,(void *(*)(void *))new_thread_trampoline
,th
))) {
551 FSHOW_SIGNAL((stderr
, "init, size, addr = %d, %d, %d\n", initcode
, sizecode
, addrcode
));
552 FSHOW_SIGNAL((stderr
, printf("pthread_create returned %d, errno %d\n", retcode
, errno
)));
553 FSHOW_SIGNAL((stderr
, "wanted stack size %d, min stack size %d\n",
554 THREAD_CONTROL_STACK_SIZE
-16, PTHREAD_STACK_MIN
));
556 perror("create_os_thread");
561 #ifdef QUEUE_FREEABLE_THREAD_STACKS
562 free_freeable_stacks();
564 thread_sigmask(SIG_SETMASK
,&oldset
,0);
565 #ifdef LOCK_CREATE_THREAD
566 retcode
= pthread_mutex_unlock(&create_thread_lock
);
567 gc_assert(retcode
== 0);
568 FSHOW_SIGNAL((stderr
,"/create_os_thread: released lock\n"));
573 os_thread_t
create_thread(lispobj initial_function
) {
577 /* Assuming that a fresh thread struct has no lisp objects in it,
578 * linking it to all_threads can be left to the thread itself
579 * without fear of gc lossage. initial_function violates this
580 * assumption and must stay pinned until the child starts up. */
581 th
= create_thread_struct(initial_function
);
584 if (create_os_thread(th
,&kid_tid
)) {
587 free_thread_struct(th
);
592 /* Send the signo to os_thread, retry if the rt signal queue is
595 kill_thread_safely(os_thread_t os_thread
, int signo
)
598 /* The man page does not mention EAGAIN as a valid return value
599 * for either pthread_kill or kill. But that's theory, this is
600 * practice. By waiting here we assume that the delivery of this
601 * signal is not necessary for the delivery of the signals in the
602 * queue. In other words, we _assume_ there are no deadlocks. */
603 while ((r
=pthread_kill(os_thread
,signo
))==EAGAIN
) {
604 /* wait a bit then try again in the hope of the rt signal
605 * queue not being full */
606 FSHOW_SIGNAL((stderr
,"/rt signal queue full\n"));
607 /* FIXME: some kind of backoff (random, exponential) would be
614 int signal_interrupt_thread(os_thread_t os_thread
)
616 int status
= kill_thread_safely(os_thread
, SIG_INTERRUPT_THREAD
);
619 } else if (status
== ESRCH
) {
622 lose("cannot send SIG_INTERRUPT_THREAD to thread=%lu: %d, %s\n",
623 os_thread
, status
, strerror(status
));
627 /* stopping the world is a two-stage process. From this thread we signal
628 * all the others with SIG_STOP_FOR_GC. The handler for this signal does
629 * the usual pseudo-atomic checks (we don't want to stop a thread while
630 * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC.
633 /* To avoid deadlocks when gc stops the world all clients of each
634 * mutex must enable or disable SIG_STOP_FOR_GC for the duration of
635 * holding the lock, but they must agree on which. */
636 void gc_stop_the_world()
638 struct thread
*p
,*th
=arch_os_get_current_thread();
639 int status
, lock_ret
;
640 #ifdef LOCK_CREATE_THREAD
641 /* KLUDGE: Stopping the thread during pthread_create() causes deadlock
643 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on create_thread_lock, thread=%lu\n",
645 lock_ret
= pthread_mutex_lock(&create_thread_lock
);
646 gc_assert(lock_ret
== 0);
647 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got create_thread_lock, thread=%lu\n",
650 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on lock, thread=%lu\n",
652 /* keep threads from starting while the world is stopped. */
653 lock_ret
= pthread_mutex_lock(&all_threads_lock
); \
654 gc_assert(lock_ret
== 0);
656 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got lock, thread=%lu\n",
658 /* stop all other threads by sending them SIG_STOP_FOR_GC */
659 for(p
=all_threads
; p
; p
=p
->next
) {
660 gc_assert(p
->os_thread
!= 0);
661 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world: p->state: %x\n", p
->state
));
662 if((p
!=th
) && ((p
->state
==STATE_RUNNING
))) {
663 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world: suspending %x, os_thread %x\n",
665 status
=kill_thread_safely(p
->os_thread
,SIG_STOP_FOR_GC
);
667 /* This thread has exited. */
668 gc_assert(p
->state
==STATE_DEAD
);
670 lose("cannot send suspend thread=%lu: %d, %s\n",
671 p
->os_thread
,status
,strerror(status
));
675 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:signals sent\n"));
676 /* wait for the running threads to stop or finish */
677 for(p
=all_threads
;p
;) {
678 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world: th: %p, p: %p\n", th
, p
));
679 if((p
!=th
) && (p
->state
==STATE_RUNNING
)) {
685 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:end\n"));
688 void gc_start_the_world()
690 struct thread
*p
,*th
=arch_os_get_current_thread();
691 int status
, lock_ret
;
692 /* if a resumed thread creates a new thread before we're done with
693 * this loop, the new thread will get consed on the front of
694 * all_threads, but it won't have been stopped so won't need
696 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:begin\n"));
697 for(p
=all_threads
;p
;p
=p
->next
) {
698 gc_assert(p
->os_thread
!=0);
699 if((p
!=th
) && (p
->state
!=STATE_DEAD
)) {
700 if(p
->state
!=STATE_SUSPENDED
) {
701 lose("gc_start_the_world: wrong thread state is %d\n",
702 fixnum_value(p
->state
));
704 FSHOW_SIGNAL((stderr
, "/gc_start_the_world: resuming %lu\n",
706 p
->state
=STATE_RUNNING
;
708 #if defined(SIG_RESUME_FROM_GC)
709 status
=kill_thread_safely(p
->os_thread
,SIG_RESUME_FROM_GC
);
711 status
=kill_thread_safely(p
->os_thread
,SIG_STOP_FOR_GC
);
714 lose("cannot resume thread=%lu: %d, %s\n",
715 p
->os_thread
,status
,strerror(status
));
719 /* If we waited here until all threads leave STATE_SUSPENDED, then
720 * SIG_STOP_FOR_GC wouldn't need to be a rt signal. That has some
721 * performance implications, but does away with the 'rt signal
722 * queue full' problem. */
724 lock_ret
= pthread_mutex_unlock(&all_threads_lock
);
725 gc_assert(lock_ret
== 0);
726 #ifdef LOCK_CREATE_THREAD
727 lock_ret
= pthread_mutex_unlock(&create_thread_lock
);
728 gc_assert(lock_ret
== 0);
731 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:end\n"));