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 /* When trying to get all_threads_lock one should make sure that
35 * sig_stop_for_gc is not blocked. Else there would be a possible
36 * deadlock: gc locks it, other thread blocks signals, gc sends stop
37 * request to other thread and waits, other thread blocks on lock. */
38 void check_sig_stop_for_gc_can_arrive_or_lose()
40 /* Get the current sigmask, by blocking the empty set. */
41 sigset_t empty
,current
;
43 thread_sigmask(SIG_BLOCK
, &empty
, ¤t
);
44 if (sigismember(¤t
,SIG_STOP_FOR_GC
))
45 lose("SIG_STOP_FOR_GC is blocked\n");
46 if (SymbolValue(INTERRUPTS_ENABLED
,arch_os_get_current_thread()) == NIL
)
47 lose("interrupts disabled\n");
48 if (arch_pseudo_atomic_atomic(NULL
))
49 lose("n pseudo atomic\n");
53 #define FSHOW_SIGNAL FSHOW
55 #define FSHOW_SIGNAL(args)
58 #define GET_ALL_THREADS_LOCK(name) \
60 sigset_t _newset,_oldset; \
61 sigemptyset(&_newset); \
62 sigaddset_blockable(&_newset); \
63 sigdelset(&_newset,SIG_STOP_FOR_GC); \
64 thread_sigmask(SIG_BLOCK, &_newset, &_oldset); \
65 check_sig_stop_for_gc_can_arrive_or_lose(); \
66 FSHOW_SIGNAL((stderr,"/%s:waiting on lock=%ld, thread=%ld\n",name, \
67 all_threads_lock,arch_os_get_current_thread()->os_thread)); \
68 get_spinlock(&all_threads_lock,(long)arch_os_get_current_thread()); \
69 FSHOW_SIGNAL((stderr,"/%s:got lock, thread=%ld\n", \
70 name,arch_os_get_current_thread()->os_thread));
72 #define RELEASE_ALL_THREADS_LOCK(name) \
73 FSHOW_SIGNAL((stderr,"/%s:released lock\n",name)); \
74 release_spinlock(&all_threads_lock); \
75 thread_sigmask(SIG_SETMASK,&_oldset,0); \
79 initial_thread_trampoline(struct thread
*th
)
82 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
86 function
= th
->unbound_marker
;
87 th
->unbound_marker
= UNBOUND_MARKER_WIDETAG
;
88 if(arch_os_thread_init(th
)==0) return 1;
90 if(th
->os_thread
< 1) lose("th->os_thread not set up right");
91 th
->state
=STATE_RUNNING
;
92 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
93 return call_into_lisp_first_time(function
,args
,0);
95 return funcall0(function
);
99 #ifdef LISP_FEATURE_SB_THREAD
101 /* this is the first thing that runs in the child (which is why the
102 * silly calling convention). Basically it calls the user's requested
103 * lisp function after doing arch_os_thread_init and whatever other
104 * bookkeeping needs to be done
107 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 return funcall0(function
);
120 #endif /* LISP_FEATURE_SB_THREAD */
122 /* this is called from any other thread to create the new one, and
123 * initialize all parts of it that can be initialized from another
127 struct thread
* create_thread_struct(lispobj initial_function
) {
128 union per_thread_data
*per_thread
;
129 struct thread
*th
=0; /* subdue gcc */
132 /* may as well allocate all the spaces at once: it saves us from
133 * having to decide what to do if only some of the allocations
135 spaces
=os_validate(0,
136 THREAD_CONTROL_STACK_SIZE
+
139 dynamic_values_bytes
+
143 per_thread
=(union per_thread_data
*)
145 THREAD_CONTROL_STACK_SIZE
+
150 memcpy(per_thread
,arch_os_get_current_thread(),
151 dynamic_values_bytes
);
153 #ifdef LISP_FEATURE_SB_THREAD
155 for(i
=0;i
<(dynamic_values_bytes
/sizeof(lispobj
));i
++)
156 per_thread
->dynamic_values
[i
]=UNBOUND_MARKER_WIDETAG
;
157 if(SymbolValue(FREE_TLS_INDEX
,0)==UNBOUND_MARKER_WIDETAG
)
160 make_fixnum(MAX_INTERRUPTS
+
161 sizeof(struct thread
)/sizeof(lispobj
)),
163 #define STATIC_TLS_INIT(sym,field) \
164 ((struct symbol *)(sym-OTHER_POINTER_LOWTAG))->tls_index= \
165 make_fixnum(THREAD_SLOT_OFFSET_WORDS(field))
167 STATIC_TLS_INIT(BINDING_STACK_START
,binding_stack_start
);
168 STATIC_TLS_INIT(BINDING_STACK_POINTER
,binding_stack_pointer
);
169 STATIC_TLS_INIT(CONTROL_STACK_START
,control_stack_start
);
170 STATIC_TLS_INIT(CONTROL_STACK_END
,control_stack_end
);
171 STATIC_TLS_INIT(ALIEN_STACK
,alien_stack_pointer
);
172 #ifdef LISP_FEATURE_X86
173 STATIC_TLS_INIT(PSEUDO_ATOMIC_ATOMIC
,pseudo_atomic_atomic
);
174 STATIC_TLS_INIT(PSEUDO_ATOMIC_INTERRUPTED
,pseudo_atomic_interrupted
);
176 #undef STATIC_TLS_INIT
180 th
=&per_thread
->thread
;
181 th
->control_stack_start
= spaces
;
182 th
->binding_stack_start
=
183 (lispobj
*)((void*)th
->control_stack_start
+THREAD_CONTROL_STACK_SIZE
);
184 th
->control_stack_end
= th
->binding_stack_start
;
185 th
->alien_stack_start
=
186 (lispobj
*)((void*)th
->binding_stack_start
+BINDING_STACK_SIZE
);
187 th
->binding_stack_pointer
=th
->binding_stack_start
;
190 th
->interrupt_fun
=NIL
;
191 th
->interrupt_fun_lock
=0;
192 th
->state
=STATE_STARTING
;
193 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
194 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
195 + ALIEN_STACK_SIZE
-N_WORD_BYTES
);
197 th
->alien_stack_pointer
=((void *)th
->alien_stack_start
);
199 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
200 th
->pseudo_atomic_interrupted
=0;
201 th
->pseudo_atomic_atomic
=0;
203 #ifdef LISP_FEATURE_GENCGC
204 gc_set_region_empty(&th
->alloc_region
);
207 #ifndef LISP_FEATURE_SB_THREAD
208 /* the tls-points-into-struct-thread trick is only good for threaded
209 * sbcl, because unithread sbcl doesn't have tls. So, we copy the
210 * appropriate values from struct thread here, and make sure that
211 * we use the appropriate SymbolValue macros to access any of the
212 * variable quantities from the C runtime. It's not quite OAOOM,
213 * it just feels like it */
214 SetSymbolValue(BINDING_STACK_START
,(lispobj
)th
->binding_stack_start
,th
);
215 SetSymbolValue(CONTROL_STACK_START
,(lispobj
)th
->control_stack_start
,th
);
216 SetSymbolValue(CONTROL_STACK_END
,(lispobj
)th
->control_stack_end
,th
);
217 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
218 SetSymbolValue(BINDING_STACK_POINTER
,(lispobj
)th
->binding_stack_pointer
,th
);
219 SetSymbolValue(ALIEN_STACK
,(lispobj
)th
->alien_stack_pointer
,th
);
220 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC
,(lispobj
)th
->pseudo_atomic_atomic
,th
);
221 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED
,th
->pseudo_atomic_interrupted
,th
);
223 current_binding_stack_pointer
=th
->binding_stack_pointer
;
224 current_control_stack_pointer
=th
->control_stack_start
;
227 bind_variable(CURRENT_CATCH_BLOCK
,make_fixnum(0),th
);
228 bind_variable(CURRENT_UNWIND_PROTECT_BLOCK
,make_fixnum(0),th
);
229 bind_variable(FREE_INTERRUPT_CONTEXT_INDEX
,make_fixnum(0),th
);
230 bind_variable(INTERRUPT_PENDING
, NIL
,th
);
231 bind_variable(INTERRUPTS_ENABLED
,T
,th
);
233 th
->interrupt_data
= (struct interrupt_data
*)
234 os_validate(0,(sizeof (struct interrupt_data
)));
236 memcpy(th
->interrupt_data
,
237 arch_os_get_current_thread()->interrupt_data
,
238 sizeof (struct interrupt_data
));
240 memcpy(th
->interrupt_data
,global_interrupt_data
,
241 sizeof (struct interrupt_data
));
243 th
->unbound_marker
=initial_function
;
247 void link_thread(struct thread
*th
,os_thread_t kid_tid
)
249 if (all_threads
) all_threads
->prev
=th
;
250 th
->next
=all_threads
;
253 /* note that th->os_thread is 0 at this time. We rely on
254 * all_threads_lock to ensure that we don't have >1 thread with
255 * os_thread=0 on the list at once
257 protect_control_stack_guard_page(th
,1);
258 /* child will not start until this is set */
259 th
->os_thread
=kid_tid
;
262 void create_initial_thread(lispobj initial_function
) {
263 struct thread
*th
=create_thread_struct(initial_function
);
264 os_thread_t kid_tid
=thread_self();
265 if(th
&& kid_tid
>0) {
266 link_thread(th
,kid_tid
);
267 initial_thread_trampoline(all_threads
); /* no return */
268 } else lose("can't create initial thread");
271 #ifdef LISP_FEATURE_SB_THREAD
273 boolean
create_os_thread(struct thread
*th
,os_thread_t
*kid_tid
)
275 /* The new thread inherits the restrictive signal mask set here,
276 * and enables signals again when it is set up properly. */
278 sigset_t newset
,oldset
;
280 sigemptyset(&newset
);
281 sigaddset_blockable(&newset
);
282 thread_sigmask(SIG_BLOCK
, &newset
, &oldset
);
284 if((pthread_attr_init(&attr
)) ||
285 (pthread_attr_setstack(&attr
,th
->control_stack_start
,
286 THREAD_CONTROL_STACK_SIZE
-16)) ||
288 (kid_tid
,&attr
,(void *(*)(void *))new_thread_trampoline
,th
)))
290 thread_sigmask(SIG_SETMASK
,&oldset
,0);
294 struct thread
*create_thread(lispobj initial_function
) {
296 os_thread_t kid_tid
=0;
299 if(linux_no_threads_p
) return 0;
301 th
=create_thread_struct(initial_function
);
304 /* we must not be interrupted here after a successful
305 * create_os_thread, because the kid will be waiting for its
306 * thread struct to be linked */
307 GET_ALL_THREADS_LOCK("create_thread")
309 success
=create_os_thread(th
,&kid_tid
);
311 link_thread(th
,kid_tid
);
313 os_invalidate((os_vm_address_t
) th
->control_stack_start
,
315 * (th
->control_stack_end
-th
->control_stack_start
)) +
316 BINDING_STACK_SIZE
+ALIEN_STACK_SIZE
+dynamic_values_bytes
+
319 RELEASE_ALL_THREADS_LOCK("create_thread")
328 #if defined LISP_FEATURE_SB_THREAD
329 /* This is not needed unless #+SB-THREAD, as there's a trivial null
330 * unithread definition. */
332 /* called from lisp from the thread object finalizer */
333 void reap_dead_thread(struct thread
*th
)
335 if(th
->state
!=STATE_DEAD
)
336 lose("thread %lx is not joinable, state=%d\n",th
,th
->state
);
337 #ifdef LISP_FEATURE_GENCGC
339 sigset_t newset
,oldset
;
340 sigemptyset(&newset
);
341 sigaddset_blockable(&newset
);
342 thread_sigmask(SIG_BLOCK
, &newset
, &oldset
);
343 gc_alloc_update_page_tables(0, &th
->alloc_region
);
344 release_spinlock(&all_threads_lock
);
345 thread_sigmask(SIG_SETMASK
,&oldset
,0);
348 GET_ALL_THREADS_LOCK("reap_dead_thread")
349 FSHOW((stderr
,"/reap_dead_thread: reaping %ld\n",th
->os_thread
));
351 th
->prev
->next
=th
->next
;
352 else all_threads
=th
->next
;
354 th
->next
->prev
=th
->prev
;
355 RELEASE_ALL_THREADS_LOCK("reap_dead_thread")
356 if(th
->tls_cookie
>=0) arch_os_thread_cleanup(th
);
357 gc_assert(pthread_join(th
->os_thread
,NULL
)==0);
358 os_invalidate((os_vm_address_t
) th
->control_stack_start
,
360 * (th
->control_stack_end
-th
->control_stack_start
)) +
361 BINDING_STACK_SIZE
+ALIEN_STACK_SIZE
+dynamic_values_bytes
+
365 int interrupt_thread(struct thread
*th
, lispobj function
)
367 /* A thread may also become dead after this test. */
368 if ((th
->state
!= STATE_DEAD
)) {
369 /* In clone_threads, if A and B both interrupt C at
370 * approximately the same time, it does not matter: the
371 * second signal will be masked until the handler has
372 * returned from the first one. In pthreads though, we
373 * can't put the knowledge of what function to call into
374 * the siginfo, so we have to store it in the destination
375 * thread, and do it in such a way that A won't clobber
376 * B's interrupt. Hence this stupid linked list.
378 * This does depend on SIG_INTERRUPT_THREAD being queued
379 * (as POSIX RT signals are): we need to keep
380 * interrupt_fun data for exactly as many signals as are
381 * going to be received by the destination thread.
383 struct cons
*c
=alloc_cons(function
,NIL
);
385 /* interrupt_thread_handler locks this spinlock with
386 * interrupts blocked and it does so for the sake of
387 * arrange_return_to_lisp_function, so we must also block
389 sigset_t newset
,oldset
;
390 sigemptyset(&newset
);
391 sigaddset_blockable(&newset
);
392 thread_sigmask(SIG_BLOCK
, &newset
, &oldset
);
393 get_spinlock(&th
->interrupt_fun_lock
,
394 (long)arch_os_get_current_thread());
395 kill_status
=thread_kill(th
->os_thread
,SIG_INTERRUPT_THREAD
);
397 ((struct cons
*)native_pointer(c
))->cdr
=th
->interrupt_fun
;
400 release_spinlock(&th
->interrupt_fun_lock
);
401 thread_sigmask(SIG_SETMASK
,&oldset
,0);
402 return (kill_status
? -1 : 0);
404 errno
=EPERM
; return -1;
407 /* stopping the world is a two-stage process. From this thread we signal
408 * all the others with SIG_STOP_FOR_GC. The handler for this signal does
409 * the usual pseudo-atomic checks (we don't want to stop a thread while
410 * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC.
413 /* To avoid deadlocks when gc stops the world all clients of each
414 * mutex must enable or disable SIG_STOP_FOR_GC for the duration of
415 * holding the lock, but they must agree on which. */
416 void gc_stop_the_world()
418 struct thread
*p
,*th
=arch_os_get_current_thread();
419 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:waiting on lock, thread=%ld\n",
421 /* keep threads from starting while the world is stopped. */
422 get_spinlock(&all_threads_lock
,(long)th
);
423 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:got lock, thread=%ld\n",
425 /* stop all other threads by sending them SIG_STOP_FOR_GC */
426 for(p
=all_threads
; p
; p
=p
->next
) {
427 while(p
->state
==STATE_STARTING
) sched_yield();
428 if((p
!=th
) && (p
->state
==STATE_RUNNING
)) {
429 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:sending sig_stop to %ld\n",
431 if(thread_kill(p
->os_thread
,SIG_STOP_FOR_GC
)==-1) {
432 /* we can't kill the thread; assume because it died
433 * since we last checked */
435 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:assuming %ld dead\n",
440 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:signals sent\n"));
441 /* wait for the running threads to stop or finish */
442 for(p
=all_threads
;p
;) {
443 gc_assert(p
->os_thread
!=0);
444 gc_assert(p
->state
!=STATE_STARTING
);
445 if((p
==th
) || (p
->state
==STATE_SUSPENDED
) ||
446 (p
->state
==STATE_DEAD
)) {
450 FSHOW_SIGNAL((stderr
,"/gc_stop_the_world:end\n"));
453 void gc_start_the_world()
455 struct thread
*p
,*th
=arch_os_get_current_thread();
456 /* if a resumed thread creates a new thread before we're done with
457 * this loop, the new thread will get consed on the front of
458 * all_threads, but it won't have been stopped so won't need
460 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:begin\n"));
461 for(p
=all_threads
;p
;p
=p
->next
) {
462 gc_assert(p
->os_thread
!=0);
463 if((p
!=th
) && (p
->state
!=STATE_DEAD
)) {
464 if(p
->state
!=STATE_SUSPENDED
) {
465 lose("gc_start_the_world: wrong thread state is %ld\n",
466 fixnum_value(p
->state
));
468 thread_kill(p
->os_thread
,SIG_STOP_FOR_GC
);
471 /* we must wait for all threads to leave stopped state else we
472 * risk signal accumulation and lose any meaning of
474 for(p
=all_threads
;p
;) {
475 if((p
==th
) || (p
->state
!=STATE_SUSPENDED
)) {
479 release_spinlock(&all_threads_lock
);
480 FSHOW_SIGNAL((stderr
,"/gc_start_the_world:end\n"));