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 */
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 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
;
97 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
98 extern lispobj
call_into_lisp_first_time(lispobj fun
, lispobj
*args
, int nargs
);
102 link_thread(struct thread
*th
)
104 if (all_threads
) all_threads
->prev
=th
;
105 th
->next
=all_threads
;
110 #ifdef LISP_FEATURE_SB_THREAD
112 unlink_thread(struct thread
*th
)
115 th
->prev
->next
= th
->next
;
117 all_threads
= th
->next
;
119 th
->next
->prev
= th
->prev
;
124 initial_thread_trampoline(struct thread
*th
)
127 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
128 lispobj
*args
= NULL
;
130 function
= th
->no_tls_value_marker
;
131 th
->no_tls_value_marker
= NO_TLS_VALUE_MARKER_WIDETAG
;
132 if(arch_os_thread_init(th
)==0) return 1;
134 th
->os_thread
=thread_self();
135 #ifndef LISP_FEATURE_WIN32
136 protect_control_stack_hard_guard_page(1, NULL
);
137 protect_binding_stack_hard_guard_page(1, NULL
);
138 protect_alien_stack_hard_guard_page(1, NULL
);
139 protect_control_stack_guard_page(1, NULL
);
140 protect_binding_stack_guard_page(1, NULL
);
141 protect_alien_stack_guard_page(1, NULL
);
144 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
145 return call_into_lisp_first_time(function
,args
,0);
147 return funcall0(function
);
151 #ifdef LISP_FEATURE_SB_THREAD
152 #define THREAD_STATE_LOCK_SIZE \
153 (sizeof(pthread_mutex_t))+(sizeof(pthread_cond_t))
155 #define THREAD_STATE_LOCK_SIZE 0
158 #define THREAD_STRUCT_SIZE (thread_control_stack_size + BINDING_STACK_SIZE + \
160 THREAD_STATE_LOCK_SIZE + \
161 dynamic_values_bytes + \
163 THREAD_ALIGNMENT_BYTES)
165 #ifdef LISP_FEATURE_SB_THREAD
166 /* THREAD POST MORTEM CLEANUP
168 * Memory allocated for the thread stacks cannot be reclaimed while
169 * the thread is still alive, so we need a mechanism for post mortem
170 * cleanups. FIXME: We actually have three, for historical reasons as
171 * the saying goes. Do we really need three? Nikodemus guesses that
172 * not anymore, now that we properly call pthread_attr_destroy before
173 * freeing the stack. */
175 static struct thread_post_mortem
*
176 plan_thread_post_mortem(struct thread
*corpse
)
179 struct thread_post_mortem
*post_mortem
= malloc(sizeof(struct thread_post_mortem
));
180 gc_assert(post_mortem
);
181 post_mortem
->os_thread
= corpse
->os_thread
;
182 post_mortem
->os_attr
= corpse
->os_attr
;
183 post_mortem
->os_address
= corpse
->os_address
;
184 #ifdef DELAY_THREAD_POST_MORTEM
185 post_mortem
->next
= NULL
;
189 /* FIXME: When does this happen? */
195 perform_thread_post_mortem(struct thread_post_mortem
*post_mortem
)
197 #ifdef CREATE_POST_MORTEM_THREAD
198 pthread_detach(pthread_self());
201 gc_assert(!pthread_join(post_mortem
->os_thread
, NULL
));
202 gc_assert(!pthread_attr_destroy(post_mortem
->os_attr
));
203 free(post_mortem
->os_attr
);
204 os_invalidate(post_mortem
->os_address
, THREAD_STRUCT_SIZE
);
210 schedule_thread_post_mortem(struct thread
*corpse
)
212 struct thread_post_mortem
*post_mortem
= NULL
;
214 post_mortem
= plan_thread_post_mortem(corpse
);
216 #ifdef DELAY_THREAD_POST_MORTEM
217 pthread_mutex_lock(&thread_post_mortem_lock
);
218 /* First stick the new post mortem to the end of the queue. */
219 if (pending_thread_post_mortem
) {
220 struct thread_post_mortem
*next
= pending_thread_post_mortem
;
224 next
->next
= post_mortem
;
226 pending_thread_post_mortem
= post_mortem
;
228 /* Then, if there are enough things in the queue, clean up one
229 * from the head -- or increment the count, and null out the
230 * post_mortem we have. */
231 if (pending_thread_post_mortem_count
> DELAY_THREAD_POST_MORTEM
) {
232 post_mortem
= pending_thread_post_mortem
;
233 pending_thread_post_mortem
= post_mortem
->next
;
235 pending_thread_post_mortem_count
++;
238 pthread_mutex_unlock(&thread_post_mortem_lock
);
239 /* Finally run, the cleanup, if any. */
240 perform_thread_post_mortem(post_mortem
);
241 #elif defined(CREATE_POST_MORTEM_THREAD)
242 gc_assert(!pthread_create(&thread
, NULL
, perform_thread_post_mortem
, post_mortem
));
244 post_mortem
= (struct thread_post_mortem
*)
245 swap_lispobjs((lispobj
*)(void *)&pending_thread_post_mortem
,
246 (lispobj
)post_mortem
);
247 perform_thread_post_mortem(post_mortem
);
252 /* this is the first thing that runs in the child (which is why the
253 * silly calling convention). Basically it calls the user's requested
254 * lisp function after doing arch_os_thread_init and whatever other
255 * bookkeeping needs to be done
258 new_thread_trampoline(struct thread
*th
)
261 int result
, lock_ret
;
263 FSHOW((stderr
,"/creating thread %lu\n", thread_self()));
264 check_deferrables_blocked_or_lose(0);
265 check_gc_signals_unblocked_or_lose(0);
266 function
= th
->no_tls_value_marker
;
267 th
->no_tls_value_marker
= NO_TLS_VALUE_MARKER_WIDETAG
;
268 if(arch_os_thread_init(th
)==0) {
269 /* FIXME: handle error */
270 lose("arch_os_thread_init failed\n");
273 th
->os_thread
=thread_self();
274 protect_control_stack_guard_page(1, NULL
);
275 protect_binding_stack_guard_page(1, NULL
);
276 protect_alien_stack_guard_page(1, NULL
);
277 /* Since GC can only know about this thread from the all_threads
278 * list and we're just adding this thread to it, there is no
279 * danger of deadlocking even with SIG_STOP_FOR_GC blocked (which
281 lock_ret
= pthread_mutex_lock(&all_threads_lock
);
282 gc_assert(lock_ret
== 0);
284 lock_ret
= pthread_mutex_unlock(&all_threads_lock
);
285 gc_assert(lock_ret
== 0);
287 result
= funcall0(function
);
290 block_blockable_signals(0, 0);
291 set_thread_state(th
, STATE_DEAD
);
293 /* SIG_STOP_FOR_GC is blocked and GC might be waiting for this
294 * thread, but since we are already dead it won't wait long. */
295 lock_ret
= pthread_mutex_lock(&all_threads_lock
);
296 gc_assert(lock_ret
== 0);
298 gc_alloc_update_page_tables(BOXED_PAGE_FLAG
, &th
->alloc_region
);
300 pthread_mutex_unlock(&all_threads_lock
);
301 gc_assert(lock_ret
== 0);
303 if(th
->tls_cookie
>=0) arch_os_thread_cleanup(th
);
304 pthread_mutex_destroy(th
->state_lock
);
305 pthread_cond_destroy(th
->state_cond
);
307 os_invalidate((os_vm_address_t
)th
->interrupt_data
,
308 (sizeof (struct interrupt_data
)));
310 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
311 FSHOW((stderr
, "Deallocating mach port %x\n", THREAD_STRUCT_TO_EXCEPTION_PORT(th
)));
312 mach_port_move_member(mach_task_self(),
313 THREAD_STRUCT_TO_EXCEPTION_PORT(th
),
315 mach_port_deallocate(mach_task_self(),
316 THREAD_STRUCT_TO_EXCEPTION_PORT(th
));
317 mach_port_destroy(mach_task_self(),
318 THREAD_STRUCT_TO_EXCEPTION_PORT(th
));
321 schedule_thread_post_mortem(th
);
322 FSHOW((stderr
,"/exiting thread %lu\n", thread_self()));
326 #endif /* LISP_FEATURE_SB_THREAD */
329 free_thread_struct(struct thread
*th
)
331 if (th
->interrupt_data
)
332 os_invalidate((os_vm_address_t
) th
->interrupt_data
,
333 (sizeof (struct interrupt_data
)));
334 os_invalidate((os_vm_address_t
) th
->os_address
,
338 /* this is called from any other thread to create the new one, and
339 * initialize all parts of it that can be initialized from another
343 static struct thread
*
344 create_thread_struct(lispobj initial_function
) {
345 union per_thread_data
*per_thread
;
346 struct thread
*th
=0; /* subdue gcc */
348 void *aligned_spaces
=0;
349 #ifdef LISP_FEATURE_SB_THREAD
353 /* May as well allocate all the spaces at once: it saves us from
354 * having to decide what to do if only some of the allocations
355 * succeed. SPACES must be appropriately aligned, since the GC
356 * expects the control stack to start at a page boundary -- and
357 * the OS may have even more rigorous requirements. We can't rely
358 * on the alignment passed from os_validate, since that might
359 * assume the current (e.g. 4k) pagesize, while we calculate with
360 * the biggest (e.g. 64k) pagesize allowed by the ABI. */
361 spaces
=os_validate(0, THREAD_STRUCT_SIZE
);
364 /* Aligning up is safe as THREAD_STRUCT_SIZE has
365 * THREAD_ALIGNMENT_BYTES padding. */
366 aligned_spaces
= (void *)((((unsigned long)(char *)spaces
)
367 + THREAD_ALIGNMENT_BYTES
-1)
368 &~(unsigned long)(THREAD_ALIGNMENT_BYTES
-1));
369 per_thread
=(union per_thread_data
*)
371 thread_control_stack_size
+
374 THREAD_STATE_LOCK_SIZE
);
376 #ifdef LISP_FEATURE_SB_THREAD
377 for(i
= 0; i
< (dynamic_values_bytes
/ sizeof(lispobj
)); i
++)
378 per_thread
->dynamic_values
[i
] = NO_TLS_VALUE_MARKER_WIDETAG
;
379 if (all_threads
== 0) {
380 if(SymbolValue(FREE_TLS_INDEX
,0)==UNBOUND_MARKER_WIDETAG
) {
383 /* FIXME: should be MAX_INTERRUPTS -1 ? */
384 make_fixnum(MAX_INTERRUPTS
+
385 sizeof(struct thread
)/sizeof(lispobj
)),
387 SetSymbolValue(TLS_INDEX_LOCK
,make_fixnum(0),0);
389 #define STATIC_TLS_INIT(sym,field) \
390 ((struct symbol *)(sym-OTHER_POINTER_LOWTAG))->tls_index= \
391 make_fixnum(THREAD_SLOT_OFFSET_WORDS(field))
393 STATIC_TLS_INIT(BINDING_STACK_START
,binding_stack_start
);
394 STATIC_TLS_INIT(BINDING_STACK_POINTER
,binding_stack_pointer
);
395 STATIC_TLS_INIT(CONTROL_STACK_START
,control_stack_start
);
396 STATIC_TLS_INIT(CONTROL_STACK_END
,control_stack_end
);
397 STATIC_TLS_INIT(ALIEN_STACK
,alien_stack_pointer
);
398 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
399 STATIC_TLS_INIT(PSEUDO_ATOMIC_BITS
,pseudo_atomic_bits
);
401 #undef STATIC_TLS_INIT
405 th
=&per_thread
->thread
;
406 th
->os_address
= spaces
;
407 th
->control_stack_start
= aligned_spaces
;
408 th
->binding_stack_start
=
409 (lispobj
*)((void*)th
->control_stack_start
+thread_control_stack_size
);
410 th
->control_stack_end
= th
->binding_stack_start
;
411 th
->alien_stack_start
=
412 (lispobj
*)((void*)th
->binding_stack_start
+BINDING_STACK_SIZE
);
413 th
->binding_stack_pointer
=th
->binding_stack_start
;
416 #ifdef LISP_FEATURE_SB_THREAD
417 th
->os_attr
=malloc(sizeof(pthread_attr_t
));
418 th
->state_lock
=(pthread_mutex_t
*)((void *)th
->alien_stack_start
+
420 pthread_mutex_init(th
->state_lock
, NULL
);
421 th
->state_cond
=(pthread_cond_t
*)((void *)th
->state_lock
+
422 (sizeof(pthread_mutex_t
)));
423 pthread_cond_init(th
->state_cond
, NULL
);
425 th
->state
=STATE_RUNNING
;
426 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
427 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
428 + ALIEN_STACK_SIZE
-N_WORD_BYTES
);
430 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
);
432 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
433 th
->pseudo_atomic_bits
=0;
435 #ifdef LISP_FEATURE_GENCGC
436 gc_set_region_empty(&th
->alloc_region
);
439 #ifndef LISP_FEATURE_SB_THREAD
440 /* the tls-points-into-struct-thread trick is only good for threaded
441 * sbcl, because unithread sbcl doesn't have tls. So, we copy the
442 * appropriate values from struct thread here, and make sure that
443 * we use the appropriate SymbolValue macros to access any of the
444 * variable quantities from the C runtime. It's not quite OAOOM,
445 * it just feels like it */
446 SetSymbolValue(BINDING_STACK_START
,(lispobj
)th
->binding_stack_start
,th
);
447 SetSymbolValue(CONTROL_STACK_START
,(lispobj
)th
->control_stack_start
,th
);
448 SetSymbolValue(CONTROL_STACK_END
,(lispobj
)th
->control_stack_end
,th
);
449 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
450 SetSymbolValue(BINDING_STACK_POINTER
,(lispobj
)th
->binding_stack_pointer
,th
);
451 SetSymbolValue(ALIEN_STACK
,(lispobj
)th
->alien_stack_pointer
,th
);
452 SetSymbolValue(PSEUDO_ATOMIC_BITS
,(lispobj
)th
->pseudo_atomic_bits
,th
);
454 current_binding_stack_pointer
=th
->binding_stack_pointer
;
455 current_control_stack_pointer
=th
->control_stack_start
;
458 bind_variable(CURRENT_CATCH_BLOCK
,make_fixnum(0),th
);
459 bind_variable(CURRENT_UNWIND_PROTECT_BLOCK
,make_fixnum(0),th
);
460 bind_variable(FREE_INTERRUPT_CONTEXT_INDEX
,make_fixnum(0),th
);
461 bind_variable(INTERRUPT_PENDING
, NIL
,th
);
462 bind_variable(INTERRUPTS_ENABLED
,T
,th
);
463 bind_variable(ALLOW_WITH_INTERRUPTS
,T
,th
);
464 bind_variable(GC_PENDING
,NIL
,th
);
465 bind_variable(ALLOC_SIGNAL
,NIL
,th
);
466 #ifdef LISP_FEATURE_SB_THREAD
467 bind_variable(STOP_FOR_GC_PENDING
,NIL
,th
);
470 th
->interrupt_data
= (struct interrupt_data
*)
471 os_validate(0,(sizeof (struct interrupt_data
)));
472 if (!th
->interrupt_data
) {
473 free_thread_struct(th
);
476 th
->interrupt_data
->pending_handler
= 0;
477 th
->interrupt_data
->gc_blocked_deferrables
= 0;
478 #ifdef LISP_FEATURE_PPC
479 th
->interrupt_data
->allocation_trap_context
= 0;
481 th
->no_tls_value_marker
=initial_function
;
487 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
488 mach_port_t
setup_mach_exception_handling_thread();
489 kern_return_t
mach_thread_init(mach_port_t thread_exception_port
);
493 void create_initial_thread(lispobj initial_function
) {
494 struct thread
*th
=create_thread_struct(initial_function
);
496 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
497 setup_mach_exception_handling_thread();
499 initial_thread_trampoline(th
); /* no return */
500 } else lose("can't create initial thread\n");
503 #ifdef LISP_FEATURE_SB_THREAD
505 #ifndef __USE_XOPEN2K
506 extern int pthread_attr_setstack (pthread_attr_t
*__attr
, void *__stackaddr
,
510 boolean
create_os_thread(struct thread
*th
,os_thread_t
*kid_tid
)
512 /* The new thread inherits the restrictive signal mask set here,
513 * and enables signals again when it is set up properly. */
516 int retcode
= 0, initcode
;
518 FSHOW_SIGNAL((stderr
,"/create_os_thread: creating new thread\n"));
520 /* Blocking deferrable signals is enough, no need to block
521 * SIG_STOP_FOR_GC because the child process is not linked onto
522 * all_threads until it's ready. */
523 block_deferrable_signals(0, &oldset
);
525 #ifdef LOCK_CREATE_THREAD
526 retcode
= pthread_mutex_lock(&create_thread_lock
);
527 gc_assert(retcode
== 0);
528 FSHOW_SIGNAL((stderr
,"/create_os_thread: got lock\n"));
531 if((initcode
= pthread_attr_init(th
->os_attr
)) ||
532 /* call_into_lisp_first_time switches the stack for the initial
533 * thread. For the others, we use this. */
534 (pthread_attr_setstack(th
->os_attr
,th
->control_stack_start
,
535 thread_control_stack_size
)) ||
536 (retcode
= pthread_create
537 (kid_tid
,th
->os_attr
,(void *(*)(void *))new_thread_trampoline
,th
))) {
538 FSHOW_SIGNAL((stderr
, "init = %d\n", initcode
));
539 FSHOW_SIGNAL((stderr
, "pthread_create returned %d, errno %d\n",
542 perror("create_os_thread");
547 #ifdef LOCK_CREATE_THREAD
548 retcode
= pthread_mutex_unlock(&create_thread_lock
);
549 gc_assert(retcode
== 0);
550 FSHOW_SIGNAL((stderr
,"/create_os_thread: released lock\n"));
552 thread_sigmask(SIG_SETMASK
,&oldset
,0);
556 os_thread_t
create_thread(lispobj initial_function
) {
557 struct thread
*th
, *thread
= arch_os_get_current_thread();
558 os_thread_t kid_tid
= 0;
560 /* Must defend against async unwinds. */
561 if (SymbolValue(INTERRUPTS_ENABLED
, thread
) != NIL
)
562 lose("create_thread is not safe when interrupts are enabled.\n");
564 /* Assuming that a fresh thread struct has no lisp objects in it,
565 * linking it to all_threads can be left to the thread itself
566 * without fear of gc lossage. initial_function violates this
567 * assumption and must stay pinned until the child starts up. */
568 th
= create_thread_struct(initial_function
);
569 if (th
&& !create_os_thread(th
,&kid_tid
)) {
570 free_thread_struct(th
);
576 /* stopping the world is a two-stage process. From this thread we signal
577 * all the others with SIG_STOP_FOR_GC. The handler for this signal does
578 * the usual pseudo-atomic checks (we don't want to stop a thread while
579 * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC.
582 /* To avoid deadlocks when gc stops the world all clients of each
583 * mutex must enable or disable SIG_STOP_FOR_GC for the duration of
584 * holding the lock, but they must agree on which. */
585 void gc_stop_the_world()
587 struct thread
*p
,*th
=arch_os_get_current_thread();
588 int status
, lock_ret
;
589 #ifdef LOCK_CREATE_THREAD
590 /* KLUDGE: Stopping the thread during pthread_create() causes deadlock
592 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on create_thread_lock\n"));
593 lock_ret
= pthread_mutex_lock(&create_thread_lock
);
594 gc_assert(lock_ret
== 0);
595 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got create_thread_lock\n"));
597 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on lock\n"));
598 /* keep threads from starting while the world is stopped. */
599 lock_ret
= pthread_mutex_lock(&all_threads_lock
); \
600 gc_assert(lock_ret
== 0);
602 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got lock\n"));
603 /* stop all other threads by sending them SIG_STOP_FOR_GC */
604 for(p
=all_threads
; p
; p
=p
->next
) {
605 gc_assert(p
->os_thread
!= 0);
606 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world: thread=%lu, state=%x\n",
607 p
->os_thread
, thread_state(p
)));
608 if((p
!=th
) && ((thread_state(p
)==STATE_RUNNING
))) {
609 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world: suspending thread %lu\n",
611 /* We already hold all_thread_lock, P can become DEAD but
612 * cannot exit, ergo it's safe to use pthread_kill. */
613 status
=pthread_kill(p
->os_thread
,SIG_STOP_FOR_GC
);
615 /* This thread has exited. */
616 gc_assert(thread_state(p
)==STATE_DEAD
);
618 lose("cannot send suspend thread=%lu: %d, %s\n",
619 p
->os_thread
,status
,strerror(status
));
623 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:signals sent\n"));
624 for(p
=all_threads
;p
;p
=p
->next
) {
628 "/gc_stop_the_world: waiting for thread=%lu: state=%x\n",
629 p
->os_thread
, thread_state(p
)));
630 wait_for_thread_state_change(p
, STATE_RUNNING
);
631 if (p
->state
== STATE_RUNNING
)
632 lose("/gc_stop_the_world: unexpected state");
635 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:end\n"));
638 void gc_start_the_world()
640 struct thread
*p
,*th
=arch_os_get_current_thread();
642 /* if a resumed thread creates a new thread before we're done with
643 * this loop, the new thread will get consed on the front of
644 * all_threads, but it won't have been stopped so won't need
646 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:begin\n"));
647 for(p
=all_threads
;p
;p
=p
->next
) {
648 gc_assert(p
->os_thread
!=0);
650 lispobj state
= thread_state(p
);
651 if (state
!= STATE_DEAD
) {
652 if(state
!= STATE_SUSPENDED
) {
653 lose("gc_start_the_world: wrong thread state is %d\n",
654 fixnum_value(state
));
656 FSHOW_SIGNAL((stderr
, "/gc_start_the_world: resuming %lu\n",
658 set_thread_state(p
, STATE_RUNNING
);
663 lock_ret
= pthread_mutex_unlock(&all_threads_lock
);
664 gc_assert(lock_ret
== 0);
665 #ifdef LOCK_CREATE_THREAD
666 lock_ret
= pthread_mutex_unlock(&create_thread_lock
);
667 gc_assert(lock_ret
== 0);
670 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:end\n"));
677 #ifdef LISP_FEATURE_SB_THREAD
678 return sched_yield();
684 /* If the thread id given does not belong to a running thread (it has
685 * exited or never even existed) pthread_kill _may_ fail with ESRCH,
686 * but it is also allowed to just segfault, see
687 * <http://udrepper.livejournal.com/16844.html>.
689 * Relying on thread ids can easily backfire since ids are recycled
690 * (NPTL recycles them extremely fast) so a signal can be sent to
691 * another process if the one it was sent to exited.
693 * We send signals in two places: signal_interrupt_thread sends a
694 * signal that's harmless if delivered to another thread, but
695 * SIG_STOP_FOR_GC is fatal.
697 * For these reasons, we must make sure that the thread is still alive
698 * when the pthread_kill is called and return if the thread is
701 kill_safely(os_thread_t os_thread
, int signal
)
703 FSHOW_SIGNAL((stderr
,"/kill_safely: %lu, %d\n", os_thread
, signal
));
705 #ifdef LISP_FEATURE_SB_THREAD
707 struct thread
*thread
;
708 /* pthread_kill is not async signal safe and we don't want to be
709 * interrupted while holding the lock. */
710 block_deferrable_signals(0, &oldset
);
711 pthread_mutex_lock(&all_threads_lock
);
712 for (thread
= all_threads
; thread
; thread
= thread
->next
) {
713 if (thread
->os_thread
== os_thread
) {
714 int status
= pthread_kill(os_thread
, signal
);
716 lose("kill_safely: pthread_kill failed with %d\n", status
);
720 pthread_mutex_unlock(&all_threads_lock
);
721 thread_sigmask(SIG_SETMASK
,&oldset
,0);
729 lose("kill_safely: who do you want to kill? %d?\n", os_thread
);
730 /* Dubious (as in don't know why it works) workaround for the
731 * signal sometimes not being generated on darwin. */
732 #ifdef LISP_FEATURE_DARWIN
735 sigprocmask(SIG_BLOCK
, &deferrable_sigset
, &oldset
);
736 status
= raise(signal
);
737 sigprocmask(SIG_SETMASK
,&oldset
,0);
740 status
= raise(signal
);
745 lose("cannot raise signal %d, %d %s\n",
746 signal
, status
, strerror(errno
));