13 #include "validate.h" /* for CONTROL_STACK_SIZE etc */
17 #include "target-arch-os.h"
21 #include "genesis/cons.h"
22 #include "genesis/fdefn.h"
23 #include "interr.h" /* for lose() */
24 #include "gc-internal.h"
26 #define ALIEN_STACK_SIZE (1*1024*1024) /* 1Mb size chosen at random */
28 int dynamic_values_bytes
=4096*sizeof(lispobj
); /* same for all threads */
29 struct thread
*all_threads
;
30 volatile lispobj all_threads_lock
;
31 extern struct interrupt_data
* global_interrupt_data
;
32 extern int linux_no_threads_p
;
34 #ifdef LISP_FEATURE_SB_THREAD
35 /* When trying to get all_threads_lock one should make sure that
36 * sig_stop_for_gc is not blocked. Else there would be a possible
37 * deadlock: gc locks it, other thread blocks signals, gc sends stop
38 * request to other thread and waits, other thread blocks on lock. */
39 void check_sig_stop_for_gc_can_arrive_or_lose()
41 /* Get the current sigmask, by blocking the empty set. */
42 sigset_t empty
,current
;
44 thread_sigmask(SIG_BLOCK
, &empty
, ¤t
);
45 if (sigismember(¤t
,SIG_STOP_FOR_GC
))
46 lose("SIG_STOP_FOR_GC cannot arrive: it is blocked\n");
47 if (SymbolValue(GC_INHIBIT
,arch_os_get_current_thread()) != NIL
)
48 lose("SIG_STOP_FOR_GC cannot arrive: gc is inhibited\n");
49 if (arch_pseudo_atomic_atomic(NULL
))
50 lose("SIG_STOP_FOR_GC cannot arrive: in pseudo atomic\n");
53 #define GET_ALL_THREADS_LOCK(name) \
55 sigset_t _newset,_oldset; \
56 sigemptyset(&_newset); \
57 sigaddset_deferrable(&_newset); \
58 thread_sigmask(SIG_BLOCK, &_newset, &_oldset); \
59 check_sig_stop_for_gc_can_arrive_or_lose(); \
60 FSHOW_SIGNAL((stderr,"/%s:waiting on lock=%ld, thread=%lu\n",name, \
61 all_threads_lock,arch_os_get_current_thread()->os_thread)); \
62 get_spinlock(&all_threads_lock,(long)arch_os_get_current_thread()); \
63 FSHOW_SIGNAL((stderr,"/%s:got lock, thread=%lu\n", \
64 name,arch_os_get_current_thread()->os_thread));
66 #define RELEASE_ALL_THREADS_LOCK(name) \
67 FSHOW_SIGNAL((stderr,"/%s:released lock\n",name)); \
68 release_spinlock(&all_threads_lock); \
69 thread_sigmask(SIG_SETMASK,&_oldset,0); \
74 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
75 extern lispobj
call_into_lisp_first_time(lispobj fun
, lispobj
*args
, int nargs
);
79 initial_thread_trampoline(struct thread
*th
)
82 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
85 function
= th
->unbound_marker
;
86 th
->unbound_marker
= UNBOUND_MARKER_WIDETAG
;
87 if(arch_os_thread_init(th
)==0) return 1;
89 if(th
->os_thread
< 1) lose("th->os_thread not set up right");
90 th
->state
=STATE_RUNNING
;
91 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
92 return call_into_lisp_first_time(function
,args
,0);
94 return funcall0(function
);
98 #ifdef LISP_FEATURE_SB_THREAD
100 /* this is the first thing that runs in the child (which is why the
101 * silly calling convention). Basically it calls the user's requested
102 * lisp function after doing arch_os_thread_init and whatever other
103 * bookkeeping needs to be done
106 new_thread_trampoline(struct thread
*th
)
110 function
= th
->unbound_marker
;
111 th
->unbound_marker
= UNBOUND_MARKER_WIDETAG
;
112 if(arch_os_thread_init(th
)==0) return 1;
114 /* wait here until our thread is linked into all_threads: see below */
115 while(th
->os_thread
<1) sched_yield();
117 th
->state
=STATE_RUNNING
;
118 result
= funcall0(function
);
119 th
->state
=STATE_DEAD
;
122 #endif /* LISP_FEATURE_SB_THREAD */
124 /* this is called from any other thread to create the new one, and
125 * initialize all parts of it that can be initialized from another
129 struct thread
* create_thread_struct(lispobj initial_function
) {
130 union per_thread_data
*per_thread
;
131 struct thread
*th
=0; /* subdue gcc */
134 /* may as well allocate all the spaces at once: it saves us from
135 * having to decide what to do if only some of the allocations
137 spaces
=os_validate(0,
138 THREAD_CONTROL_STACK_SIZE
+
141 dynamic_values_bytes
+
145 per_thread
=(union per_thread_data
*)
147 THREAD_CONTROL_STACK_SIZE
+
152 memcpy(per_thread
,arch_os_get_current_thread(),
153 dynamic_values_bytes
);
155 #ifdef LISP_FEATURE_SB_THREAD
157 for(i
=0;i
<(dynamic_values_bytes
/sizeof(lispobj
));i
++)
158 per_thread
->dynamic_values
[i
]=UNBOUND_MARKER_WIDETAG
;
159 if(SymbolValue(FREE_TLS_INDEX
,0)==UNBOUND_MARKER_WIDETAG
)
162 make_fixnum(MAX_INTERRUPTS
+
163 sizeof(struct thread
)/sizeof(lispobj
)),
165 #define STATIC_TLS_INIT(sym,field) \
166 ((struct symbol *)(sym-OTHER_POINTER_LOWTAG))->tls_index= \
167 make_fixnum(THREAD_SLOT_OFFSET_WORDS(field))
169 STATIC_TLS_INIT(BINDING_STACK_START
,binding_stack_start
);
170 STATIC_TLS_INIT(BINDING_STACK_POINTER
,binding_stack_pointer
);
171 STATIC_TLS_INIT(CONTROL_STACK_START
,control_stack_start
);
172 STATIC_TLS_INIT(CONTROL_STACK_END
,control_stack_end
);
173 STATIC_TLS_INIT(ALIEN_STACK
,alien_stack_pointer
);
174 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
175 STATIC_TLS_INIT(PSEUDO_ATOMIC_ATOMIC
,pseudo_atomic_atomic
);
176 STATIC_TLS_INIT(PSEUDO_ATOMIC_INTERRUPTED
,pseudo_atomic_interrupted
);
178 #undef STATIC_TLS_INIT
182 th
=&per_thread
->thread
;
183 th
->control_stack_start
= spaces
;
184 th
->binding_stack_start
=
185 (lispobj
*)((void*)th
->control_stack_start
+THREAD_CONTROL_STACK_SIZE
);
186 th
->control_stack_end
= th
->binding_stack_start
;
187 th
->alien_stack_start
=
188 (lispobj
*)((void*)th
->binding_stack_start
+BINDING_STACK_SIZE
);
189 th
->binding_stack_pointer
=th
->binding_stack_start
;
192 th
->interrupt_fun
=NIL
;
193 th
->interrupt_fun_lock
=0;
194 th
->state
=STATE_STARTING
;
195 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
196 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
197 + ALIEN_STACK_SIZE
-N_WORD_BYTES
);
199 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
);
201 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
202 th
->pseudo_atomic_interrupted
=0;
203 th
->pseudo_atomic_atomic
=0;
205 #ifdef LISP_FEATURE_GENCGC
206 gc_set_region_empty(&th
->alloc_region
);
209 #ifndef LISP_FEATURE_SB_THREAD
210 /* the tls-points-into-struct-thread trick is only good for threaded
211 * sbcl, because unithread sbcl doesn't have tls. So, we copy the
212 * appropriate values from struct thread here, and make sure that
213 * we use the appropriate SymbolValue macros to access any of the
214 * variable quantities from the C runtime. It's not quite OAOOM,
215 * it just feels like it */
216 SetSymbolValue(BINDING_STACK_START
,(lispobj
)th
->binding_stack_start
,th
);
217 SetSymbolValue(CONTROL_STACK_START
,(lispobj
)th
->control_stack_start
,th
);
218 SetSymbolValue(CONTROL_STACK_END
,(lispobj
)th
->control_stack_end
,th
);
219 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
220 SetSymbolValue(BINDING_STACK_POINTER
,(lispobj
)th
->binding_stack_pointer
,th
);
221 SetSymbolValue(ALIEN_STACK
,(lispobj
)th
->alien_stack_pointer
,th
);
222 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC
,(lispobj
)th
->pseudo_atomic_atomic
,th
);
223 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED
,th
->pseudo_atomic_interrupted
,th
);
225 current_binding_stack_pointer
=th
->binding_stack_pointer
;
226 current_control_stack_pointer
=th
->control_stack_start
;
229 bind_variable(CURRENT_CATCH_BLOCK
,make_fixnum(0),th
);
230 bind_variable(CURRENT_UNWIND_PROTECT_BLOCK
,make_fixnum(0),th
);
231 bind_variable(FREE_INTERRUPT_CONTEXT_INDEX
,make_fixnum(0),th
);
232 bind_variable(INTERRUPT_PENDING
, NIL
,th
);
233 bind_variable(INTERRUPTS_ENABLED
,T
,th
);
234 bind_variable(GC_PENDING
,NIL
,th
);
235 #ifdef LISP_FEATURE_SB_THREAD
236 bind_variable(STOP_FOR_GC_PENDING
,NIL
,th
);
239 th
->interrupt_data
= (struct interrupt_data
*)
240 os_validate(0,(sizeof (struct interrupt_data
)));
242 memcpy(th
->interrupt_data
,
243 arch_os_get_current_thread()->interrupt_data
,
244 sizeof (struct interrupt_data
));
246 memcpy(th
->interrupt_data
,global_interrupt_data
,
247 sizeof (struct interrupt_data
));
249 th
->unbound_marker
=initial_function
;
253 void link_thread(struct thread
*th
,os_thread_t kid_tid
)
255 if (all_threads
) all_threads
->prev
=th
;
256 th
->next
=all_threads
;
259 /* note that th->os_thread is 0 at this time. We rely on
260 * all_threads_lock to ensure that we don't have >1 thread with
261 * os_thread=0 on the list at once
263 protect_control_stack_guard_page(th
,1);
264 /* child will not start until this is set */
265 th
->os_thread
=kid_tid
;
268 void create_initial_thread(lispobj initial_function
) {
269 struct thread
*th
=create_thread_struct(initial_function
);
270 os_thread_t kid_tid
=thread_self();
271 if(th
&& kid_tid
>0) {
272 link_thread(th
,kid_tid
);
273 initial_thread_trampoline(all_threads
); /* no return */
274 } else lose("can't create initial thread");
277 #ifdef LISP_FEATURE_SB_THREAD
279 #ifndef __USE_XOPEN2K
280 extern int pthread_attr_setstack (pthread_attr_t
*__attr
, void *__stackaddr
,
284 boolean
create_os_thread(struct thread
*th
,os_thread_t
*kid_tid
)
286 /* The new thread inherits the restrictive signal mask set here,
287 * and enables signals again when it is set up properly. */
289 sigset_t newset
,oldset
;
291 sigemptyset(&newset
);
292 sigaddset_deferrable(&newset
);
293 thread_sigmask(SIG_BLOCK
, &newset
, &oldset
);
295 if((pthread_attr_init(&attr
)) ||
296 (pthread_attr_setstack(&attr
,th
->control_stack_start
,
297 THREAD_CONTROL_STACK_SIZE
-16)) ||
299 (kid_tid
,&attr
,(void *(*)(void *))new_thread_trampoline
,th
)))
301 thread_sigmask(SIG_SETMASK
,&oldset
,0);
305 struct thread
*create_thread(lispobj initial_function
) {
307 os_thread_t kid_tid
=0;
310 if(linux_no_threads_p
) return 0;
312 th
=create_thread_struct(initial_function
);
315 /* we must not be interrupted here after a successful
316 * create_os_thread, because the kid will be waiting for its
317 * thread struct to be linked */
318 GET_ALL_THREADS_LOCK("create_thread")
320 success
=create_os_thread(th
,&kid_tid
);
322 link_thread(th
,kid_tid
);
324 os_invalidate((os_vm_address_t
) th
->control_stack_start
,
326 * (th
->control_stack_end
-th
->control_stack_start
)) +
327 BINDING_STACK_SIZE
+ALIEN_STACK_SIZE
+dynamic_values_bytes
+
330 RELEASE_ALL_THREADS_LOCK("create_thread")
338 /* called from lisp from the thread object finalizer */
339 void reap_dead_thread(struct thread
*th
)
341 if(th
->state
!=STATE_DEAD
)
342 lose("thread %p is not joinable, state=%d\n",th
,th
->state
);
343 #ifdef LISP_FEATURE_GENCGC
345 sigset_t newset
,oldset
;
346 sigemptyset(&newset
);
347 sigaddset_blockable(&newset
);
348 thread_sigmask(SIG_BLOCK
, &newset
, &oldset
);
349 gc_alloc_update_page_tables(0, &th
->alloc_region
);
350 release_spinlock(&all_threads_lock
);
351 thread_sigmask(SIG_SETMASK
,&oldset
,0);
354 GET_ALL_THREADS_LOCK("reap_dead_thread")
355 FSHOW((stderr
,"/reap_dead_thread: reaping %lu\n",th
->os_thread
));
357 th
->prev
->next
=th
->next
;
358 else all_threads
=th
->next
;
360 th
->next
->prev
=th
->prev
;
361 RELEASE_ALL_THREADS_LOCK("reap_dead_thread")
362 if(th
->tls_cookie
>=0) arch_os_thread_cleanup(th
);
363 gc_assert(pthread_join(th
->os_thread
,NULL
)==0);
364 os_invalidate((os_vm_address_t
) th
->control_stack_start
,
366 * (th
->control_stack_end
-th
->control_stack_start
)) +
367 BINDING_STACK_SIZE
+ALIEN_STACK_SIZE
+dynamic_values_bytes
+
371 int interrupt_thread(struct thread
*th
, lispobj function
)
373 /* A thread may also become dead after this test. */
374 if ((th
->state
!= STATE_DEAD
)) {
375 /* In clone_threads, if A and B both interrupt C at
376 * approximately the same time, it does not matter: the
377 * second signal will be masked until the handler has
378 * returned from the first one. In pthreads though, we
379 * can't put the knowledge of what function to call into
380 * the siginfo, so we have to store it in the destination
381 * thread, and do it in such a way that A won't clobber
382 * B's interrupt. Hence this stupid linked list.
384 * This does depend on SIG_INTERRUPT_THREAD being queued
385 * (as POSIX RT signals are): we need to keep
386 * interrupt_fun data for exactly as many signals as are
387 * going to be received by the destination thread.
389 lispobj c
=alloc_cons(function
,NIL
);
391 /* interrupt_thread_handler locks this spinlock with
392 * interrupts blocked (it does so for the sake of
393 * arrange_return_to_lisp_function), so we must also block
394 * them or else SIG_STOP_FOR_GC and all_threads_lock will find
395 * a way to deadlock. */
396 sigset_t newset
,oldset
;
397 sigemptyset(&newset
);
398 sigaddset_blockable(&newset
);
399 thread_sigmask(SIG_BLOCK
, &newset
, &oldset
);
400 get_spinlock(&th
->interrupt_fun_lock
,
401 (long)arch_os_get_current_thread());
402 kill_status
=thread_kill(th
->os_thread
,SIG_INTERRUPT_THREAD
);
404 ((struct cons
*)native_pointer(c
))->cdr
=th
->interrupt_fun
;
407 release_spinlock(&th
->interrupt_fun_lock
);
408 thread_sigmask(SIG_SETMASK
,&oldset
,0);
409 return (kill_status
? -1 : 0);
411 errno
=EPERM
; return -1;
414 /* stopping the world is a two-stage process. From this thread we signal
415 * all the others with SIG_STOP_FOR_GC. The handler for this signal does
416 * the usual pseudo-atomic checks (we don't want to stop a thread while
417 * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC.
420 /* To avoid deadlocks when gc stops the world all clients of each
421 * mutex must enable or disable SIG_STOP_FOR_GC for the duration of
422 * holding the lock, but they must agree on which. */
423 void gc_stop_the_world()
425 struct thread
*p
,*th
=arch_os_get_current_thread();
426 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on lock, thread=%lu\n",
428 /* keep threads from starting while the world is stopped. */
429 get_spinlock(&all_threads_lock
,(long)th
);
430 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got lock, thread=%lu\n",
432 /* stop all other threads by sending them SIG_STOP_FOR_GC */
433 for(p
=all_threads
; p
; p
=p
->next
) {
434 while(p
->state
==STATE_STARTING
) sched_yield();
435 if((p
!=th
) && (p
->state
==STATE_RUNNING
)) {
436 FSHOW_SIGNAL((stderr
, "/gc_stop_the_world: suspending %lu\n",
438 if(thread_kill(p
->os_thread
,SIG_STOP_FOR_GC
)==-1) {
439 /* we can't kill the thread; assume because it died
440 * since we last checked */
442 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:assuming %lu dead\n",
447 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:signals sent\n"));
448 /* wait for the running threads to stop or finish */
449 for(p
=all_threads
;p
;) {
450 gc_assert(p
->os_thread
!=0);
451 gc_assert(p
->state
!=STATE_STARTING
);
452 if((p
==th
) || (p
->state
==STATE_SUSPENDED
) ||
453 (p
->state
==STATE_DEAD
)) {
459 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:end\n"));
462 void gc_start_the_world()
464 struct thread
*p
,*th
=arch_os_get_current_thread();
465 /* if a resumed thread creates a new thread before we're done with
466 * this loop, the new thread will get consed on the front of
467 * all_threads, but it won't have been stopped so won't need
469 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:begin\n"));
470 for(p
=all_threads
;p
;p
=p
->next
) {
471 gc_assert(p
->os_thread
!=0);
472 if((p
!=th
) && (p
->state
!=STATE_DEAD
)) {
473 if(p
->state
!=STATE_SUSPENDED
) {
474 lose("gc_start_the_world: wrong thread state is %d\n",
475 fixnum_value(p
->state
));
477 FSHOW_SIGNAL((stderr
, "/gc_start_the_world: resuming %lu\n",
479 p
->state
=STATE_RUNNING
;
480 thread_kill(p
->os_thread
,SIG_STOP_FOR_GC
);
483 release_spinlock(&all_threads_lock
);
484 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:end\n"));