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 BINDING_STACK_SIZE etc */
38 #include "target-arch-os.h"
42 #include "genesis/cons.h"
43 #include "genesis/fdefn.h"
44 #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 DELAY_THREAD_POST_MORTEM 5
58 #define LOCK_CREATE_THREAD
61 #ifdef LISP_FEATURE_FREEBSD
62 #define CREATE_CLEANUP_THREAD
63 #define LOCK_CREATE_THREAD
66 #ifdef LISP_FEATURE_SB_THREAD
67 struct thread_post_mortem
{
68 #ifdef DELAY_THREAD_POST_MORTEM
69 struct thread_post_mortem
*next
;
71 os_thread_t os_thread
;
72 pthread_attr_t
*os_attr
;
73 os_vm_address_t os_address
;
76 #ifdef DELAY_THREAD_POST_MORTEM
77 static int pending_thread_post_mortem_count
= 0;
78 pthread_mutex_t thread_post_mortem_lock
= PTHREAD_MUTEX_INITIALIZER
;
80 static struct thread_post_mortem
* volatile pending_thread_post_mortem
= 0;
83 int dynamic_values_bytes
=TLS_SIZE
*sizeof(lispobj
); /* same for all threads */
84 struct thread
*all_threads
;
85 extern struct interrupt_data
* global_interrupt_data
;
87 #ifdef LISP_FEATURE_SB_THREAD
88 pthread_mutex_t all_threads_lock
= PTHREAD_MUTEX_INITIALIZER
;
89 #ifdef LOCK_CREATE_THREAD
90 static pthread_mutex_t create_thread_lock
= PTHREAD_MUTEX_INITIALIZER
;
92 #ifdef LISP_FEATURE_GCC_TLS
93 __thread
struct thread
*current_thread
;
95 pthread_key_t lisp_thread
= 0;
98 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
99 extern lispobj
call_into_lisp_first_time(lispobj fun
, lispobj
*args
, int nargs
);
103 link_thread(struct thread
*th
)
105 if (all_threads
) all_threads
->prev
=th
;
106 th
->next
=all_threads
;
111 #ifdef LISP_FEATURE_SB_THREAD
113 unlink_thread(struct thread
*th
)
116 th
->prev
->next
= th
->next
;
118 all_threads
= th
->next
;
120 th
->next
->prev
= th
->prev
;
125 initial_thread_trampoline(struct thread
*th
)
128 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
129 lispobj
*args
= NULL
;
131 #ifdef LISP_FEATURE_SB_THREAD
132 pthread_setspecific(lisp_thread
, (void *)1);
134 function
= th
->no_tls_value_marker
;
135 th
->no_tls_value_marker
= NO_TLS_VALUE_MARKER_WIDETAG
;
136 if(arch_os_thread_init(th
)==0) return 1;
138 th
->os_thread
=thread_self();
139 #ifndef LISP_FEATURE_WIN32
140 protect_control_stack_hard_guard_page(1, NULL
);
141 protect_binding_stack_hard_guard_page(1, NULL
);
142 protect_alien_stack_hard_guard_page(1, NULL
);
143 protect_control_stack_guard_page(1, NULL
);
144 protect_binding_stack_guard_page(1, NULL
);
145 protect_alien_stack_guard_page(1, NULL
);
148 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
149 return call_into_lisp_first_time(function
,args
,0);
151 return funcall0(function
);
155 #ifdef LISP_FEATURE_SB_THREAD
156 #define THREAD_STATE_LOCK_SIZE \
157 (sizeof(pthread_mutex_t))+(sizeof(pthread_cond_t))
159 #define THREAD_STATE_LOCK_SIZE 0
162 #define THREAD_STRUCT_SIZE (thread_control_stack_size + BINDING_STACK_SIZE + \
164 THREAD_STATE_LOCK_SIZE + \
165 dynamic_values_bytes + \
167 THREAD_ALIGNMENT_BYTES)
169 #ifdef LISP_FEATURE_SB_THREAD
170 /* THREAD POST MORTEM CLEANUP
172 * Memory allocated for the thread stacks cannot be reclaimed while
173 * the thread is still alive, so we need a mechanism for post mortem
174 * cleanups. FIXME: We actually have three, for historical reasons as
175 * the saying goes. Do we really need three? Nikodemus guesses that
176 * not anymore, now that we properly call pthread_attr_destroy before
177 * freeing the stack. */
179 static struct thread_post_mortem
*
180 plan_thread_post_mortem(struct thread
*corpse
)
183 struct thread_post_mortem
*post_mortem
= malloc(sizeof(struct thread_post_mortem
));
184 gc_assert(post_mortem
);
185 post_mortem
->os_thread
= corpse
->os_thread
;
186 post_mortem
->os_attr
= corpse
->os_attr
;
187 post_mortem
->os_address
= corpse
->os_address
;
188 #ifdef DELAY_THREAD_POST_MORTEM
189 post_mortem
->next
= NULL
;
193 /* FIXME: When does this happen? */
199 perform_thread_post_mortem(struct thread_post_mortem
*post_mortem
)
201 #ifdef CREATE_POST_MORTEM_THREAD
202 pthread_detach(pthread_self());
205 gc_assert(!pthread_join(post_mortem
->os_thread
, NULL
));
206 gc_assert(!pthread_attr_destroy(post_mortem
->os_attr
));
207 free(post_mortem
->os_attr
);
208 os_invalidate(post_mortem
->os_address
, THREAD_STRUCT_SIZE
);
214 schedule_thread_post_mortem(struct thread
*corpse
)
216 struct thread_post_mortem
*post_mortem
= NULL
;
218 post_mortem
= plan_thread_post_mortem(corpse
);
220 #ifdef DELAY_THREAD_POST_MORTEM
221 pthread_mutex_lock(&thread_post_mortem_lock
);
222 /* First stick the new post mortem to the end of the queue. */
223 if (pending_thread_post_mortem
) {
224 struct thread_post_mortem
*next
= pending_thread_post_mortem
;
228 next
->next
= post_mortem
;
230 pending_thread_post_mortem
= post_mortem
;
232 /* Then, if there are enough things in the queue, clean up one
233 * from the head -- or increment the count, and null out the
234 * post_mortem we have. */
235 if (pending_thread_post_mortem_count
> DELAY_THREAD_POST_MORTEM
) {
236 post_mortem
= pending_thread_post_mortem
;
237 pending_thread_post_mortem
= post_mortem
->next
;
239 pending_thread_post_mortem_count
++;
242 pthread_mutex_unlock(&thread_post_mortem_lock
);
243 /* Finally run, the cleanup, if any. */
244 perform_thread_post_mortem(post_mortem
);
245 #elif defined(CREATE_POST_MORTEM_THREAD)
246 gc_assert(!pthread_create(&thread
, NULL
, perform_thread_post_mortem
, post_mortem
));
248 post_mortem
= (struct thread_post_mortem
*)
249 swap_lispobjs((lispobj
*)(void *)&pending_thread_post_mortem
,
250 (lispobj
)post_mortem
);
251 perform_thread_post_mortem(post_mortem
);
256 /* this is the first thing that runs in the child (which is why the
257 * silly calling convention). Basically it calls the user's requested
258 * lisp function after doing arch_os_thread_init and whatever other
259 * bookkeeping needs to be done
262 new_thread_trampoline(struct thread
*th
)
265 int result
, lock_ret
;
267 FSHOW((stderr
,"/creating thread %lu\n", thread_self()));
268 check_deferrables_blocked_or_lose(0);
269 check_gc_signals_unblocked_or_lose(0);
270 pthread_setspecific(lisp_thread
, (void *)1);
271 function
= th
->no_tls_value_marker
;
272 th
->no_tls_value_marker
= NO_TLS_VALUE_MARKER_WIDETAG
;
273 if(arch_os_thread_init(th
)==0) {
274 /* FIXME: handle error */
275 lose("arch_os_thread_init failed\n");
278 th
->os_thread
=thread_self();
279 protect_control_stack_guard_page(1, NULL
);
280 protect_binding_stack_guard_page(1, NULL
);
281 protect_alien_stack_guard_page(1, NULL
);
282 /* Since GC can only know about this thread from the all_threads
283 * list and we're just adding this thread to it, there is no
284 * danger of deadlocking even with SIG_STOP_FOR_GC blocked (which
286 lock_ret
= pthread_mutex_lock(&all_threads_lock
);
287 gc_assert(lock_ret
== 0);
289 lock_ret
= pthread_mutex_unlock(&all_threads_lock
);
290 gc_assert(lock_ret
== 0);
292 result
= funcall0(function
);
295 block_blockable_signals(0, 0);
296 set_thread_state(th
, STATE_DEAD
);
298 /* SIG_STOP_FOR_GC is blocked and GC might be waiting for this
299 * thread, but since we are already dead it won't wait long. */
300 lock_ret
= pthread_mutex_lock(&all_threads_lock
);
301 gc_assert(lock_ret
== 0);
303 gc_alloc_update_page_tables(BOXED_PAGE_FLAG
, &th
->alloc_region
);
305 pthread_mutex_unlock(&all_threads_lock
);
306 gc_assert(lock_ret
== 0);
308 if(th
->tls_cookie
>=0) arch_os_thread_cleanup(th
);
309 pthread_mutex_destroy(th
->state_lock
);
310 pthread_cond_destroy(th
->state_cond
);
312 os_invalidate((os_vm_address_t
)th
->interrupt_data
,
313 (sizeof (struct interrupt_data
)));
315 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
316 FSHOW((stderr
, "Deallocating mach port %x\n", THREAD_STRUCT_TO_EXCEPTION_PORT(th
)));
317 mach_port_move_member(mach_task_self(),
318 THREAD_STRUCT_TO_EXCEPTION_PORT(th
),
320 mach_port_deallocate(mach_task_self(),
321 THREAD_STRUCT_TO_EXCEPTION_PORT(th
));
322 mach_port_destroy(mach_task_self(),
323 THREAD_STRUCT_TO_EXCEPTION_PORT(th
));
326 schedule_thread_post_mortem(th
);
327 FSHOW((stderr
,"/exiting thread %lu\n", thread_self()));
331 #endif /* LISP_FEATURE_SB_THREAD */
334 free_thread_struct(struct thread
*th
)
336 if (th
->interrupt_data
)
337 os_invalidate((os_vm_address_t
) th
->interrupt_data
,
338 (sizeof (struct interrupt_data
)));
339 os_invalidate((os_vm_address_t
) th
->os_address
,
343 /* this is called from any other thread to create the new one, and
344 * initialize all parts of it that can be initialized from another
348 static struct thread
*
349 create_thread_struct(lispobj initial_function
) {
350 union per_thread_data
*per_thread
;
351 struct thread
*th
=0; /* subdue gcc */
353 void *aligned_spaces
=0;
354 #ifdef LISP_FEATURE_SB_THREAD
358 /* May as well allocate all the spaces at once: it saves us from
359 * having to decide what to do if only some of the allocations
360 * succeed. SPACES must be appropriately aligned, since the GC
361 * expects the control stack to start at a page boundary -- and
362 * the OS may have even more rigorous requirements. We can't rely
363 * on the alignment passed from os_validate, since that might
364 * assume the current (e.g. 4k) pagesize, while we calculate with
365 * the biggest (e.g. 64k) pagesize allowed by the ABI. */
366 spaces
=os_validate(0, THREAD_STRUCT_SIZE
);
369 /* Aligning up is safe as THREAD_STRUCT_SIZE has
370 * THREAD_ALIGNMENT_BYTES padding. */
371 aligned_spaces
= (void *)((((unsigned long)(char *)spaces
)
372 + THREAD_ALIGNMENT_BYTES
-1)
373 &~(unsigned long)(THREAD_ALIGNMENT_BYTES
-1));
374 per_thread
=(union per_thread_data
*)
376 thread_control_stack_size
+
379 THREAD_STATE_LOCK_SIZE
);
381 #ifdef LISP_FEATURE_SB_THREAD
382 for(i
= 0; i
< (dynamic_values_bytes
/ sizeof(lispobj
)); i
++)
383 per_thread
->dynamic_values
[i
] = NO_TLS_VALUE_MARKER_WIDETAG
;
384 if (all_threads
== 0) {
385 if(SymbolValue(FREE_TLS_INDEX
,0)==UNBOUND_MARKER_WIDETAG
) {
388 /* FIXME: should be MAX_INTERRUPTS -1 ? */
389 make_fixnum(MAX_INTERRUPTS
+
390 sizeof(struct thread
)/sizeof(lispobj
)),
392 SetSymbolValue(TLS_INDEX_LOCK
,make_fixnum(0),0);
394 #define STATIC_TLS_INIT(sym,field) \
395 ((struct symbol *)(sym-OTHER_POINTER_LOWTAG))->tls_index= \
396 make_fixnum(THREAD_SLOT_OFFSET_WORDS(field))
398 STATIC_TLS_INIT(BINDING_STACK_START
,binding_stack_start
);
399 STATIC_TLS_INIT(BINDING_STACK_POINTER
,binding_stack_pointer
);
400 STATIC_TLS_INIT(CONTROL_STACK_START
,control_stack_start
);
401 STATIC_TLS_INIT(CONTROL_STACK_END
,control_stack_end
);
402 STATIC_TLS_INIT(ALIEN_STACK
,alien_stack_pointer
);
403 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
404 STATIC_TLS_INIT(PSEUDO_ATOMIC_BITS
,pseudo_atomic_bits
);
406 #undef STATIC_TLS_INIT
410 th
=&per_thread
->thread
;
411 th
->os_address
= spaces
;
412 th
->control_stack_start
= aligned_spaces
;
413 th
->binding_stack_start
=
414 (lispobj
*)((void*)th
->control_stack_start
+thread_control_stack_size
);
415 th
->control_stack_end
= th
->binding_stack_start
;
416 th
->control_stack_guard_page_protected
= T
;
417 th
->alien_stack_start
=
418 (lispobj
*)((void*)th
->binding_stack_start
+BINDING_STACK_SIZE
);
419 th
->binding_stack_pointer
=th
->binding_stack_start
;
422 #ifdef LISP_FEATURE_SB_THREAD
423 th
->os_attr
=malloc(sizeof(pthread_attr_t
));
424 th
->state_lock
=(pthread_mutex_t
*)((void *)th
->alien_stack_start
+
426 pthread_mutex_init(th
->state_lock
, NULL
);
427 th
->state_cond
=(pthread_cond_t
*)((void *)th
->state_lock
+
428 (sizeof(pthread_mutex_t
)));
429 pthread_cond_init(th
->state_cond
, NULL
);
431 th
->state
=STATE_RUNNING
;
432 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
433 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
434 + ALIEN_STACK_SIZE
-N_WORD_BYTES
);
436 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
);
438 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
439 th
->pseudo_atomic_bits
=0;
441 #ifdef LISP_FEATURE_GENCGC
442 gc_set_region_empty(&th
->alloc_region
);
445 #ifndef LISP_FEATURE_SB_THREAD
446 /* the tls-points-into-struct-thread trick is only good for threaded
447 * sbcl, because unithread sbcl doesn't have tls. So, we copy the
448 * appropriate values from struct thread here, and make sure that
449 * we use the appropriate SymbolValue macros to access any of the
450 * variable quantities from the C runtime. It's not quite OAOOM,
451 * it just feels like it */
452 SetSymbolValue(BINDING_STACK_START
,(lispobj
)th
->binding_stack_start
,th
);
453 SetSymbolValue(CONTROL_STACK_START
,(lispobj
)th
->control_stack_start
,th
);
454 SetSymbolValue(CONTROL_STACK_END
,(lispobj
)th
->control_stack_end
,th
);
455 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
456 SetSymbolValue(BINDING_STACK_POINTER
,(lispobj
)th
->binding_stack_pointer
,th
);
457 SetSymbolValue(ALIEN_STACK
,(lispobj
)th
->alien_stack_pointer
,th
);
458 SetSymbolValue(PSEUDO_ATOMIC_BITS
,(lispobj
)th
->pseudo_atomic_bits
,th
);
460 current_binding_stack_pointer
=th
->binding_stack_pointer
;
461 current_control_stack_pointer
=th
->control_stack_start
;
464 bind_variable(CURRENT_CATCH_BLOCK
,make_fixnum(0),th
);
465 bind_variable(CURRENT_UNWIND_PROTECT_BLOCK
,make_fixnum(0),th
);
466 bind_variable(FREE_INTERRUPT_CONTEXT_INDEX
,make_fixnum(0),th
);
467 bind_variable(INTERRUPT_PENDING
, NIL
,th
);
468 bind_variable(INTERRUPTS_ENABLED
,T
,th
);
469 bind_variable(ALLOW_WITH_INTERRUPTS
,T
,th
);
470 bind_variable(GC_PENDING
,NIL
,th
);
471 bind_variable(ALLOC_SIGNAL
,NIL
,th
);
472 #ifdef LISP_FEATURE_SB_THREAD
473 bind_variable(STOP_FOR_GC_PENDING
,NIL
,th
);
476 th
->interrupt_data
= (struct interrupt_data
*)
477 os_validate(0,(sizeof (struct interrupt_data
)));
478 if (!th
->interrupt_data
) {
479 free_thread_struct(th
);
482 th
->interrupt_data
->pending_handler
= 0;
483 th
->interrupt_data
->gc_blocked_deferrables
= 0;
484 #ifdef LISP_FEATURE_PPC
485 th
->interrupt_data
->allocation_trap_context
= 0;
487 th
->no_tls_value_marker
=initial_function
;
493 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
494 mach_port_t
setup_mach_exception_handling_thread();
495 kern_return_t
mach_thread_init(mach_port_t thread_exception_port
);
499 void create_initial_thread(lispobj initial_function
) {
500 struct thread
*th
=create_thread_struct(initial_function
);
501 #ifdef LISP_FEATURE_SB_THREAD
502 pthread_key_create(&lisp_thread
, 0);
505 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
506 setup_mach_exception_handling_thread();
508 initial_thread_trampoline(th
); /* no return */
509 } else lose("can't create initial thread\n");
512 #ifdef LISP_FEATURE_SB_THREAD
514 #ifndef __USE_XOPEN2K
515 extern int pthread_attr_setstack (pthread_attr_t
*__attr
, void *__stackaddr
,
519 boolean
create_os_thread(struct thread
*th
,os_thread_t
*kid_tid
)
521 /* The new thread inherits the restrictive signal mask set here,
522 * and enables signals again when it is set up properly. */
525 int retcode
= 0, initcode
;
527 FSHOW_SIGNAL((stderr
,"/create_os_thread: creating new thread\n"));
529 /* Blocking deferrable signals is enough, no need to block
530 * SIG_STOP_FOR_GC because the child process is not linked onto
531 * all_threads until it's ready. */
532 block_deferrable_signals(0, &oldset
);
534 #ifdef LOCK_CREATE_THREAD
535 retcode
= pthread_mutex_lock(&create_thread_lock
);
536 gc_assert(retcode
== 0);
537 FSHOW_SIGNAL((stderr
,"/create_os_thread: got lock\n"));
540 if((initcode
= pthread_attr_init(th
->os_attr
)) ||
541 /* call_into_lisp_first_time switches the stack for the initial
542 * thread. For the others, we use this. */
543 (pthread_attr_setstack(th
->os_attr
,th
->control_stack_start
,
544 thread_control_stack_size
)) ||
545 (retcode
= pthread_create
546 (kid_tid
,th
->os_attr
,(void *(*)(void *))new_thread_trampoline
,th
))) {
547 FSHOW_SIGNAL((stderr
, "init = %d\n", initcode
));
548 FSHOW_SIGNAL((stderr
, "pthread_create returned %d, errno %d\n",
551 perror("create_os_thread");
556 #ifdef LOCK_CREATE_THREAD
557 retcode
= pthread_mutex_unlock(&create_thread_lock
);
558 gc_assert(retcode
== 0);
559 FSHOW_SIGNAL((stderr
,"/create_os_thread: released lock\n"));
561 thread_sigmask(SIG_SETMASK
,&oldset
,0);
565 os_thread_t
create_thread(lispobj initial_function
) {
566 struct thread
*th
, *thread
= arch_os_get_current_thread();
567 os_thread_t kid_tid
= 0;
569 /* Must defend against async unwinds. */
570 if (SymbolValue(INTERRUPTS_ENABLED
, thread
) != NIL
)
571 lose("create_thread is not safe when interrupts are enabled.\n");
573 /* Assuming that a fresh thread struct has no lisp objects in it,
574 * linking it to all_threads can be left to the thread itself
575 * without fear of gc lossage. initial_function violates this
576 * assumption and must stay pinned until the child starts up. */
577 th
= create_thread_struct(initial_function
);
578 if (th
&& !create_os_thread(th
,&kid_tid
)) {
579 free_thread_struct(th
);
585 /* stopping the world is a two-stage process. From this thread we signal
586 * all the others with SIG_STOP_FOR_GC. The handler for this signal does
587 * the usual pseudo-atomic checks (we don't want to stop a thread while
588 * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC.
591 /* To avoid deadlocks when gc stops the world all clients of each
592 * mutex must enable or disable SIG_STOP_FOR_GC for the duration of
593 * holding the lock, but they must agree on which. */
594 void gc_stop_the_world()
596 struct thread
*p
,*th
=arch_os_get_current_thread();
597 int status
, lock_ret
;
598 #ifdef LOCK_CREATE_THREAD
599 /* KLUDGE: Stopping the thread during pthread_create() causes deadlock
601 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on create_thread_lock\n"));
602 lock_ret
= pthread_mutex_lock(&create_thread_lock
);
603 gc_assert(lock_ret
== 0);
604 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got create_thread_lock\n"));
606 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on lock\n"));
607 /* keep threads from starting while the world is stopped. */
608 lock_ret
= pthread_mutex_lock(&all_threads_lock
); \
609 gc_assert(lock_ret
== 0);
611 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got lock\n"));
612 /* stop all other threads by sending them SIG_STOP_FOR_GC */
613 for(p
=all_threads
; p
; p
=p
->next
) {
614 gc_assert(p
->os_thread
!= 0);
615 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world: thread=%lu, state=%x\n",
616 p
->os_thread
, thread_state(p
)));
617 if((p
!=th
) && ((thread_state(p
)==STATE_RUNNING
))) {
618 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world: suspending thread %lu\n",
620 /* We already hold all_thread_lock, P can become DEAD but
621 * cannot exit, ergo it's safe to use pthread_kill. */
622 status
=pthread_kill(p
->os_thread
,SIG_STOP_FOR_GC
);
624 /* This thread has exited. */
625 gc_assert(thread_state(p
)==STATE_DEAD
);
627 lose("cannot send suspend thread=%lu: %d, %s\n",
628 p
->os_thread
,status
,strerror(status
));
632 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:signals sent\n"));
633 for(p
=all_threads
;p
;p
=p
->next
) {
637 "/gc_stop_the_world: waiting for thread=%lu: state=%x\n",
638 p
->os_thread
, thread_state(p
)));
639 wait_for_thread_state_change(p
, STATE_RUNNING
);
640 if (p
->state
== STATE_RUNNING
)
641 lose("/gc_stop_the_world: unexpected state");
644 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:end\n"));
647 void gc_start_the_world()
649 struct thread
*p
,*th
=arch_os_get_current_thread();
651 /* if a resumed thread creates a new thread before we're done with
652 * this loop, the new thread will get consed on the front of
653 * all_threads, but it won't have been stopped so won't need
655 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:begin\n"));
656 for(p
=all_threads
;p
;p
=p
->next
) {
657 gc_assert(p
->os_thread
!=0);
659 lispobj state
= thread_state(p
);
660 if (state
!= STATE_DEAD
) {
661 if(state
!= STATE_SUSPENDED
) {
662 lose("gc_start_the_world: wrong thread state is %d\n",
663 fixnum_value(state
));
665 FSHOW_SIGNAL((stderr
, "/gc_start_the_world: resuming %lu\n",
667 set_thread_state(p
, STATE_RUNNING
);
672 lock_ret
= pthread_mutex_unlock(&all_threads_lock
);
673 gc_assert(lock_ret
== 0);
674 #ifdef LOCK_CREATE_THREAD
675 lock_ret
= pthread_mutex_unlock(&create_thread_lock
);
676 gc_assert(lock_ret
== 0);
679 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:end\n"));
686 #ifdef LISP_FEATURE_SB_THREAD
687 return sched_yield();
693 /* If the thread id given does not belong to a running thread (it has
694 * exited or never even existed) pthread_kill _may_ fail with ESRCH,
695 * but it is also allowed to just segfault, see
696 * <http://udrepper.livejournal.com/16844.html>.
698 * Relying on thread ids can easily backfire since ids are recycled
699 * (NPTL recycles them extremely fast) so a signal can be sent to
700 * another process if the one it was sent to exited.
702 * We send signals in two places: signal_interrupt_thread sends a
703 * signal that's harmless if delivered to another thread, but
704 * SIG_STOP_FOR_GC is fatal.
706 * For these reasons, we must make sure that the thread is still alive
707 * when the pthread_kill is called and return if the thread is
710 kill_safely(os_thread_t os_thread
, int signal
)
712 FSHOW_SIGNAL((stderr
,"/kill_safely: %lu, %d\n", os_thread
, signal
));
714 #ifdef LISP_FEATURE_SB_THREAD
716 struct thread
*thread
;
717 /* pthread_kill is not async signal safe and we don't want to be
718 * interrupted while holding the lock. */
719 block_deferrable_signals(0, &oldset
);
720 pthread_mutex_lock(&all_threads_lock
);
721 for (thread
= all_threads
; thread
; thread
= thread
->next
) {
722 if (thread
->os_thread
== os_thread
) {
723 int status
= pthread_kill(os_thread
, signal
);
725 lose("kill_safely: pthread_kill failed with %d\n", status
);
729 pthread_mutex_unlock(&all_threads_lock
);
730 thread_sigmask(SIG_SETMASK
,&oldset
,0);
738 lose("kill_safely: who do you want to kill? %d?\n", os_thread
);
739 /* Dubious (as in don't know why it works) workaround for the
740 * signal sometimes not being generated on darwin. */
741 #ifdef LISP_FEATURE_DARWIN
744 sigprocmask(SIG_BLOCK
, &deferrable_sigset
, &oldset
);
745 status
= raise(signal
);
746 sigprocmask(SIG_SETMASK
,&oldset
,0);
749 status
= raise(signal
);
754 lose("cannot raise signal %d, %d %s\n",
755 signal
, status
, strerror(errno
));