src/runtime/thread.c

   1 /*
   2  * This software is part of the SBCL system. See the README file for
   3  * more information.
   4  *
   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.
  10  */
  11
  12 #include "sbcl.h"
  13
  14 #include <stdlib.h>
  15 #include <stdio.h>
  16 #include <string.h>
  17 #ifndef LISP_FEATURE_WIN32
  18 #include <sched.h>
  19 #endif
  20 #include "runtime.h"
  21 #include <stddef.h>
  22 #include <errno.h>
  23 #include <sys/types.h>
  24 #ifndef LISP_FEATURE_WIN32
  25 #include <sys/wait.h>
  26 #endif
  27
  28 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
  29 #include <mach/mach.h>
  30 #include <mach/mach_error.h>
  31 #include <mach/mach_types.h>
  32 #endif
  33
  34 #include "runtime.h"
  35 #include "validate.h"           /* for BINDING_STACK_SIZE etc */
  36 #include "thread.h"
  37 #include "arch.h"
  38 #include "target-arch-os.h"
  39 #include "os.h"
  40 #include "globals.h"
  41 #include "dynbind.h"
  42 #include "genesis/cons.h"
  43 #include "genesis/fdefn.h"
  44 #include "interr.h"             /* for lose() */
  45 #include "alloc.h"
  46 #include "gc-internal.h"
  47 #include "cpputil.h"
  48 #include "pseudo-atomic.h"
  49 #include "interrupt.h"
  50 #include "lispregs.h"
  51
  52 #if defined(LISP_FEATURE_WIN32) && defined(LISP_FEATURE_SB_THREAD)
  53 # define IMMEDIATE_POST_MORTEM
  54 #endif
  55
  56 #if defined(LISP_FEATURE_DARWIN) && defined(LISP_FEATURE_SB_THREAD)
  57 #define DELAY_THREAD_POST_MORTEM 5
  58 #define LOCK_CREATE_THREAD
  59 #endif
  60
  61 #ifdef LISP_FEATURE_FREEBSD
  62 #define CREATE_CLEANUP_THREAD
  63 #define LOCK_CREATE_THREAD
  64 #endif
  65
  66 #ifdef LISP_FEATURE_SB_THREAD
  67 struct thread_post_mortem {
  68 #ifdef DELAY_THREAD_POST_MORTEM
  69     struct thread_post_mortem *next;
  70 #endif
  71     os_thread_t os_thread;
  72     pthread_attr_t *os_attr;
  73     os_vm_address_t os_address;
  74 };
  75
  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;
  79 #endif
  80 static struct thread_post_mortem * volatile pending_thread_post_mortem = 0;
  81 #endif
  82
  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;
  86
  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;
  91 #endif
  92 #ifdef LISP_FEATURE_GCC_TLS
  93 __thread struct thread *current_thread;
  94 #endif
  95 pthread_key_t lisp_thread = 0;
  96 #endif
  97
  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)
 100 # ifdef LISP_FEATURE_X86_64
 101     __attribute__((sysv_abi))
 102 # endif
 103     ;
 104 #endif
 105
 106 static void
 107 link_thread(struct thread *th)
 108 {
 109     if (all_threads) all_threads->prev=th;
 110     th->next=all_threads;
 111     th->prev=0;
 112     all_threads=th;
 113 }
 114
 115 #ifdef LISP_FEATURE_SB_THREAD
 116 static void
 117 unlink_thread(struct thread *th)
 118 {
 119     if (th->prev)
 120         th->prev->next = th->next;
 121     else
 122         all_threads = th->next;
 123     if (th->next)
 124         th->next->prev = th->prev;
 125 }
 126
 127 #ifndef LISP_FEATURE_SB_SAFEPOINT
 128 /* Only access thread state with blockables blocked. */
 129 lispobj
 130 thread_state(struct thread *thread)
 131 {
 132     lispobj state;
 133     sigset_t old;
 134     block_blockable_signals(NULL, &old);
 135     os_sem_wait(thread->state_sem, "thread_state");
 136     state = thread->state;
 137     os_sem_post(thread->state_sem, "thread_state");
 138     thread_sigmask(SIG_SETMASK, &old, NULL);
 139     return state;
 140 }
 141
 142 void
 143 set_thread_state(struct thread *thread, lispobj state)
 144 {
 145     int i, waitcount = 0;
 146     sigset_t old;
 147     block_blockable_signals(NULL, &old);
 148     os_sem_wait(thread->state_sem, "set_thread_state");
 149     if (thread->state != state) {
 150         if ((STATE_STOPPED==state) ||
 151             (STATE_DEAD==state)) {
 152             waitcount = thread->state_not_running_waitcount;
 153             thread->state_not_running_waitcount = 0;
 154             for (i=0; i<waitcount; i++)
 155                 os_sem_post(thread->state_not_running_sem, "set_thread_state (not running)");
 156         }
 157         if ((STATE_RUNNING==state) ||
 158             (STATE_DEAD==state)) {
 159             waitcount = thread->state_not_stopped_waitcount;
 160             thread->state_not_stopped_waitcount = 0;
 161             for (i=0; i<waitcount; i++)
 162                 os_sem_post(thread->state_not_stopped_sem, "set_thread_state (not stopped)");
 163         }
 164         thread->state = state;
 165     }
 166     os_sem_post(thread->state_sem, "set_thread_state");
 167     thread_sigmask(SIG_SETMASK, &old, NULL);
 168 }
 169
 170 void
 171 wait_for_thread_state_change(struct thread *thread, lispobj state)
 172 {
 173     sigset_t old;
 174     os_sem_t *wait_sem;
 175     block_blockable_signals(NULL, &old);
 176   start:
 177     os_sem_wait(thread->state_sem, "wait_for_thread_state_change");
 178     if (thread->state == state) {
 179         switch (state) {
 180         case STATE_RUNNING:
 181             wait_sem = thread->state_not_running_sem;
 182             thread->state_not_running_waitcount++;
 183             break;
 184         case STATE_STOPPED:
 185             wait_sem = thread->state_not_stopped_sem;
 186             thread->state_not_stopped_waitcount++;
 187             break;
 188         default:
 189             lose("Invalid state in wait_for_thread_state_change: "OBJ_FMTX"\n", state);
 190         }
 191     } else {
 192         wait_sem = NULL;
 193     }
 194     os_sem_post(thread->state_sem, "wait_for_thread_state_change");
 195     if (wait_sem) {
 196         os_sem_wait(wait_sem, "wait_for_thread_state_change");
 197         goto start;
 198     }
 199     thread_sigmask(SIG_SETMASK, &old, NULL);
 200 }
 201 #endif /* sb-safepoint */
 202 #endif /* sb-thread */
 203
 204 static int
 205 initial_thread_trampoline(struct thread *th)
 206 {
 207     lispobj function;
 208 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 209     lispobj *args = NULL;
 210 #endif
 211 #ifdef LISP_FEATURE_SB_THREAD
 212     pthread_setspecific(lisp_thread, (void *)1);
 213 #endif
 214 #if defined(THREADS_USING_GCSIGNAL) && defined(LISP_FEATURE_PPC)
 215     /* SIG_STOP_FOR_GC defaults to blocked on PPC? */
 216     unblock_gc_signals(0,0);
 217 #endif
 218     function = th->no_tls_value_marker;
 219     th->no_tls_value_marker = NO_TLS_VALUE_MARKER_WIDETAG;
 220     if(arch_os_thread_init(th)==0) return 1;
 221     link_thread(th);
 222     th->os_thread=thread_self();
 223 #ifndef LISP_FEATURE_WIN32
 224     protect_control_stack_hard_guard_page(1, NULL);
 225 #endif
 226     protect_binding_stack_hard_guard_page(1, NULL);
 227     protect_alien_stack_hard_guard_page(1, NULL);
 228 #ifndef LISP_FEATURE_WIN32
 229     protect_control_stack_guard_page(1, NULL);
 230 #endif
 231     protect_binding_stack_guard_page(1, NULL);
 232     protect_alien_stack_guard_page(1, NULL);
 233
 234 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 235     return call_into_lisp_first_time(function,args,0);
 236 #else
 237     return funcall0(function);
 238 #endif
 239 }
 240
 241 #ifdef LISP_FEATURE_SB_THREAD
 242
 243 # if defined(IMMEDIATE_POST_MORTEM)
 244
 245 /*
 246  * If this feature is set, we are running on a stack managed by the OS,
 247  * and no fancy delays are required for anything.  Just do it.
 248  */
 249 static void
 250 schedule_thread_post_mortem(struct thread *corpse)
 251 {
 252     pthread_detach(pthread_self());
 253     gc_assert(!pthread_attr_destroy(corpse->os_attr));
 254     free(corpse->os_attr);
 255 #if defined(LISP_FEATURE_WIN32)
 256     os_invalidate_free(corpse->os_address, THREAD_STRUCT_SIZE);
 257 #else
 258     os_invalidate(corpse->os_address, THREAD_STRUCT_SIZE);
 259 #endif
 260 }
 261
 262 # else
 263
 264 /* THREAD POST MORTEM CLEANUP
 265  *
 266  * Memory allocated for the thread stacks cannot be reclaimed while
 267  * the thread is still alive, so we need a mechanism for post mortem
 268  * cleanups. FIXME: We actually have three, for historical reasons as
 269  * the saying goes. Do we really need three? Nikodemus guesses that
 270  * not anymore, now that we properly call pthread_attr_destroy before
 271  * freeing the stack. */
 272
 273 static struct thread_post_mortem *
 274 plan_thread_post_mortem(struct thread *corpse)
 275 {
 276     if (corpse) {
 277         struct thread_post_mortem *post_mortem = malloc(sizeof(struct thread_post_mortem));
 278         gc_assert(post_mortem);
 279         post_mortem->os_thread = corpse->os_thread;
 280         post_mortem->os_attr = corpse->os_attr;
 281         post_mortem->os_address = corpse->os_address;
 282 #ifdef DELAY_THREAD_POST_MORTEM
 283         post_mortem->next = NULL;
 284 #endif
 285         return post_mortem;
 286     } else {
 287         /* FIXME: When does this happen? */
 288         return NULL;
 289     }
 290 }
 291
 292 static void
 293 perform_thread_post_mortem(struct thread_post_mortem *post_mortem)
 294 {
 295 #ifdef CREATE_POST_MORTEM_THREAD
 296     pthread_detach(pthread_self());
 297 #endif
 298     if (post_mortem) {
 299         gc_assert(!pthread_join(post_mortem->os_thread, NULL));
 300         gc_assert(!pthread_attr_destroy(post_mortem->os_attr));
 301         free(post_mortem->os_attr);
 302         os_invalidate(post_mortem->os_address, THREAD_STRUCT_SIZE);
 303         free(post_mortem);
 304     }
 305 }
 306
 307 static void
 308 schedule_thread_post_mortem(struct thread *corpse)
 309 {
 310     struct thread_post_mortem *post_mortem = NULL;
 311     if (corpse) {
 312         post_mortem = plan_thread_post_mortem(corpse);
 313
 314 #ifdef DELAY_THREAD_POST_MORTEM
 315         pthread_mutex_lock(&thread_post_mortem_lock);
 316         /* First stick the new post mortem to the end of the queue. */
 317         if (pending_thread_post_mortem) {
 318             struct thread_post_mortem *next = pending_thread_post_mortem;
 319             while (next->next) {
 320                 next = next->next;
 321             }
 322             next->next = post_mortem;
 323         } else {
 324             pending_thread_post_mortem = post_mortem;
 325         }
 326         /* Then, if there are enough things in the queue, clean up one
 327          * from the head -- or increment the count, and null out the
 328          * post_mortem we have. */
 329         if (pending_thread_post_mortem_count > DELAY_THREAD_POST_MORTEM) {
 330             post_mortem = pending_thread_post_mortem;
 331             pending_thread_post_mortem = post_mortem->next;
 332         } else {
 333             pending_thread_post_mortem_count++;
 334             post_mortem = NULL;
 335         }
 336         pthread_mutex_unlock(&thread_post_mortem_lock);
 337         /* Finally run, the cleanup, if any. */
 338         perform_thread_post_mortem(post_mortem);
 339 #elif defined(CREATE_POST_MORTEM_THREAD)
 340         gc_assert(!pthread_create(&thread, NULL, perform_thread_post_mortem, post_mortem));
 341 #else
 342         post_mortem = (struct thread_post_mortem *)
 343             swap_lispobjs((lispobj *)(void *)&pending_thread_post_mortem,
 344                           (lispobj)post_mortem);
 345         perform_thread_post_mortem(post_mortem);
 346 #endif
 347     }
 348 }
 349
 350 # endif /* !IMMEDIATE_POST_MORTEM */
 351
 352 /* Note: scribble must be stack-allocated */
 353 static void
 354 init_new_thread(struct thread *th, init_thread_data *scribble, int guardp)
 355 {
 356     int lock_ret;
 357
 358     pthread_setspecific(lisp_thread, (void *)1);
 359     if(arch_os_thread_init(th)==0) {
 360         /* FIXME: handle error */
 361         lose("arch_os_thread_init failed\n");
 362     }
 363
 364     th->os_thread=thread_self();
 365     if (guardp)
 366         protect_control_stack_guard_page(1, NULL);
 367     protect_binding_stack_guard_page(1, NULL);
 368     protect_alien_stack_guard_page(1, NULL);
 369     /* Since GC can only know about this thread from the all_threads
 370      * list and we're just adding this thread to it, there is no
 371      * danger of deadlocking even with SIG_STOP_FOR_GC blocked (which
 372      * it is not). */
 373 #ifdef LISP_FEATURE_SB_SAFEPOINT
 374     *th->csp_around_foreign_call = (lispobj)scribble;
 375 #endif
 376     lock_ret = pthread_mutex_lock(&all_threads_lock);
 377     gc_assert(lock_ret == 0);
 378     link_thread(th);
 379     lock_ret = pthread_mutex_unlock(&all_threads_lock);
 380     gc_assert(lock_ret == 0);
 381
 382     /* Kludge: Changed the order of some steps between the safepoint/
 383      * non-safepoint versions of this code.  Can we unify this more?
 384      */
 385 #ifdef LISP_FEATURE_SB_SAFEPOINT
 386     gc_state_lock();
 387     gc_state_wait(GC_NONE);
 388     gc_state_unlock();
 389     push_gcing_safety(&scribble->safety);
 390 #endif
 391 }
 392
 393 static void
 394 undo_init_new_thread(struct thread *th, init_thread_data *scribble)
 395 {
 396     int lock_ret;
 397
 398     /* Kludge: Changed the order of some steps between the safepoint/
 399      * non-safepoint versions of this code.  Can we unify this more?
 400      */
 401 #ifdef LISP_FEATURE_SB_SAFEPOINT
 402     block_blockable_signals(0, 0);
 403     gc_alloc_update_page_tables(BOXED_PAGE_FLAG, &th->alloc_region);
 404     pop_gcing_safety(&scribble->safety);
 405     lock_ret = pthread_mutex_lock(&all_threads_lock);
 406     gc_assert(lock_ret == 0);
 407     unlink_thread(th);
 408     lock_ret = pthread_mutex_unlock(&all_threads_lock);
 409     gc_assert(lock_ret == 0);
 410 #else
 411     /* Block GC */
 412     block_blockable_signals(0, 0);
 413     set_thread_state(th, STATE_DEAD);
 414
 415     /* SIG_STOP_FOR_GC is blocked and GC might be waiting for this
 416      * thread, but since we are already dead it won't wait long. */
 417     lock_ret = pthread_mutex_lock(&all_threads_lock);
 418     gc_assert(lock_ret == 0);
 419
 420     gc_alloc_update_page_tables(BOXED_PAGE_FLAG, &th->alloc_region);
 421     unlink_thread(th);
 422     pthread_mutex_unlock(&all_threads_lock);
 423     gc_assert(lock_ret == 0);
 424 #endif
 425
 426     if(th->tls_cookie>=0) arch_os_thread_cleanup(th);
 427 #ifndef LISP_FEATURE_SB_SAFEPOINT
 428     os_sem_destroy(th->state_sem);
 429     os_sem_destroy(th->state_not_running_sem);
 430     os_sem_destroy(th->state_not_stopped_sem);
 431 #endif
 432
 433 #if defined(LISP_FEATURE_WIN32)
 434     free((os_vm_address_t)th->interrupt_data);
 435 #else
 436     os_invalidate((os_vm_address_t)th->interrupt_data,
 437                   (sizeof (struct interrupt_data)));
 438 #endif
 439
 440 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
 441     mach_lisp_thread_destroy(th);
 442 #endif
 443
 444 #if defined(LISP_FEATURE_WIN32)
 445     int i;
 446     for (i = 0; i<
 447              (int) (sizeof(th->private_events.events)/
 448                     sizeof(th->private_events.events[0])); ++i) {
 449       CloseHandle(th->private_events.events[i]);
 450     }
 451     TlsSetValue(OUR_TLS_INDEX,NULL);
 452 #endif
 453
 454     /* Undo the association of the current pthread to its `struct thread',
 455      * such that we can call arch_os_get_current_thread() later in this
 456      * thread and cleanly get back NULL. */
 457 #ifdef LISP_FEATURE_GCC_TLS
 458     current_thread = NULL;
 459 #else
 460     pthread_setspecific(specials, NULL);
 461 #endif
 462
 463     schedule_thread_post_mortem(th);
 464 }
 465
 466 /* this is the first thing that runs in the child (which is why the
 467  * silly calling convention).  Basically it calls the user's requested
 468  * lisp function after doing arch_os_thread_init and whatever other
 469  * bookkeeping needs to be done
 470  */
 471 int
 472 new_thread_trampoline(struct thread *th)
 473 {
 474     int result;
 475     init_thread_data scribble;
 476
 477     FSHOW((stderr,"/creating thread %lu\n", thread_self()));
 478     check_deferrables_blocked_or_lose(0);
 479 #ifndef LISP_FEATURE_SB_SAFEPOINT
 480     check_gc_signals_unblocked_or_lose(0);
 481 #endif
 482
 483     lispobj function = th->no_tls_value_marker;
 484     th->no_tls_value_marker = NO_TLS_VALUE_MARKER_WIDETAG;
 485     init_new_thread(th, &scribble, 1);
 486     result = funcall0(function);
 487     undo_init_new_thread(th, &scribble);
 488
 489     FSHOW((stderr,"/exiting thread %lu\n", thread_self()));
 490     return result;
 491 }
 492
 493 # ifdef LISP_FEATURE_SB_SAFEPOINT
 494 static struct thread *create_thread_struct(lispobj);
 495
 496 void
 497 attach_os_thread(init_thread_data *scribble)
 498 {
 499     os_thread_t os = pthread_self();
 500     odxprint(misc, "attach_os_thread: attaching to %p", os);
 501
 502     struct thread *th = create_thread_struct(NIL);
 503     block_deferrable_signals(0, &scribble->oldset);
 504     th->no_tls_value_marker = NO_TLS_VALUE_MARKER_WIDETAG;
 505     /* We don't actually want a pthread_attr here, but rather than add
 506      * `if's to the post-mostem, let's just keep that code happy by
 507      * keeping it initialized: */
 508     pthread_attr_init(th->os_attr);
 509
 510 #ifndef LISP_FEATURE_WIN32
 511     /* On windows, arch_os_thread_init will take care of finding the
 512      * stack. */
 513     pthread_attr_t attr;
 514     int pthread_getattr_np(pthread_t, pthread_attr_t *);
 515     pthread_getattr_np(os, &attr);
 516     void *stack_addr;
 517     size_t stack_size;
 518     pthread_attr_getstack(&attr, &stack_addr, &stack_size);
 519     th->control_stack_start = stack_addr;
 520     th->control_stack_end = (void *) (((uintptr_t) stack_addr) + stack_size);
 521 #endif
 522
 523     init_new_thread(th, scribble, 0);
 524
 525     /* We will be calling into Lisp soon, and the functions being called
 526      * recklessly ignore the comment in target-thread which says that we
 527      * must be careful to not cause GC while initializing a new thread.
 528      * Since we first need to create a fresh thread object, it's really
 529      * tempting to just perform such unsafe allocation though.  So let's
 530      * at least try to suppress GC before consing, and hope that it
 531      * works: */
 532     SetSymbolValue(GC_INHIBIT, T, th);
 533
 534     uword_t stacksize
 535         = (uword_t) th->control_stack_end - (uword_t) th->control_stack_start;
 536     odxprint(misc, "attach_os_thread: attached %p as %p (0x%lx bytes stack)",
 537              os, th, (long) stacksize);
 538 }
 539
 540 void
 541 detach_os_thread(init_thread_data *scribble)
 542 {
 543     struct thread *th = arch_os_get_current_thread();
 544     odxprint(misc, "detach_os_thread: detaching");
 545
 546     undo_init_new_thread(th, scribble);
 547
 548     odxprint(misc, "deattach_os_thread: detached");
 549     pthread_setspecific(lisp_thread, (void *)0);
 550     thread_sigmask(SIG_SETMASK, &scribble->oldset, 0);
 551 }
 552 # endif /* safepoint */
 553
 554 #endif /* LISP_FEATURE_SB_THREAD */
 555
 556 static void
 557 free_thread_struct(struct thread *th)
 558 {
 559 #if defined(LISP_FEATURE_WIN32)
 560     if (th->interrupt_data) {
 561         os_invalidate_free((os_vm_address_t) th->interrupt_data,
 562                       (sizeof (struct interrupt_data)));
 563     }
 564     os_invalidate_free((os_vm_address_t) th->os_address,
 565                   THREAD_STRUCT_SIZE);
 566 #else
 567     if (th->interrupt_data)
 568         os_invalidate((os_vm_address_t) th->interrupt_data,
 569                       (sizeof (struct interrupt_data)));
 570     os_invalidate((os_vm_address_t) th->os_address,
 571                   THREAD_STRUCT_SIZE);
 572 #endif
 573 }
 574
 575 #ifdef LISP_FEATURE_SB_THREAD
 576 /* FIXME: should be MAX_INTERRUPTS -1 ? */
 577 const unsigned int tls_index_start =
 578   MAX_INTERRUPTS + sizeof(struct thread)/sizeof(lispobj);
 579 #endif
 580
 581 /* this is called from any other thread to create the new one, and
 582  * initialize all parts of it that can be initialized from another
 583  * thread
 584  */
 585
 586 static struct thread *
 587 create_thread_struct(lispobj initial_function) {
 588     union per_thread_data *per_thread;
 589     struct thread *th=0;        /*  subdue gcc */
 590     void *spaces=0;
 591     void *aligned_spaces=0;
 592 #if defined(LISP_FEATURE_SB_THREAD) || defined(LISP_FEATURE_WIN32)
 593     unsigned int i;
 594 #endif
 595
 596     /* May as well allocate all the spaces at once: it saves us from
 597      * having to decide what to do if only some of the allocations
 598      * succeed. SPACES must be appropriately aligned, since the GC
 599      * expects the control stack to start at a page boundary -- and
 600      * the OS may have even more rigorous requirements. We can't rely
 601      * on the alignment passed from os_validate, since that might
 602      * assume the current (e.g. 4k) pagesize, while we calculate with
 603      * the biggest (e.g. 64k) pagesize allowed by the ABI. */
 604     spaces=os_validate(0, THREAD_STRUCT_SIZE);
 605     if(!spaces)
 606         return NULL;
 607     /* Aligning up is safe as THREAD_STRUCT_SIZE has
 608      * THREAD_ALIGNMENT_BYTES padding. */
 609     aligned_spaces = (void *)((((uword_t)(char *)spaces)
 610                                + THREAD_ALIGNMENT_BYTES-1)
 611                               &~(uword_t)(THREAD_ALIGNMENT_BYTES-1));
 612     void* csp_page=
 613         (aligned_spaces+
 614          thread_control_stack_size+
 615          BINDING_STACK_SIZE+
 616          ALIEN_STACK_SIZE);
 617     per_thread=(union per_thread_data *)
 618         (csp_page + THREAD_CSP_PAGE_SIZE);
 619     struct nonpointer_thread_data *nonpointer_data
 620         = (void *) &per_thread->dynamic_values[TLS_SIZE];
 621
 622 #ifdef LISP_FEATURE_SB_THREAD
 623     for(i = 0; i < (dynamic_values_bytes / sizeof(lispobj)); i++)
 624         per_thread->dynamic_values[i] = NO_TLS_VALUE_MARKER_WIDETAG;
 625     if (all_threads == 0) {
 626         if(SymbolValue(FREE_TLS_INDEX,0)==UNBOUND_MARKER_WIDETAG) {
 627             SetSymbolValue(FREE_TLS_INDEX,tls_index_start << WORD_SHIFT,0);
 628             SetSymbolValue(TLS_INDEX_LOCK,make_fixnum(0),0);
 629         }
 630 #define STATIC_TLS_INIT(sym,field) \
 631   ((struct symbol *)(sym-OTHER_POINTER_LOWTAG))->tls_index= \
 632   (THREAD_SLOT_OFFSET_WORDS(field) << WORD_SHIFT)
 633
 634         STATIC_TLS_INIT(BINDING_STACK_START,binding_stack_start);
 635 #ifdef BINDING_STACK_POINTER
 636         STATIC_TLS_INIT(BINDING_STACK_POINTER,binding_stack_pointer);
 637 #endif
 638         STATIC_TLS_INIT(CONTROL_STACK_START,control_stack_start);
 639         STATIC_TLS_INIT(CONTROL_STACK_END,control_stack_end);
 640 #ifdef ALIEN_STACK
 641         STATIC_TLS_INIT(ALIEN_STACK,alien_stack_pointer);
 642 #endif
 643 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
 644         STATIC_TLS_INIT(PSEUDO_ATOMIC_BITS,pseudo_atomic_bits);
 645 #endif
 646 #undef STATIC_TLS_INIT
 647     }
 648 #endif
 649
 650     th=&per_thread->thread;
 651     th->os_address = spaces;
 652     th->control_stack_start = aligned_spaces;
 653     th->binding_stack_start=
 654         (lispobj*)((void*)th->control_stack_start+thread_control_stack_size);
 655     th->control_stack_end = th->binding_stack_start;
 656     th->control_stack_guard_page_protected = T;
 657     th->alien_stack_start=
 658         (lispobj*)((void*)th->binding_stack_start+BINDING_STACK_SIZE);
 659     set_binding_stack_pointer(th,th->binding_stack_start);
 660     th->this=th;
 661     th->os_thread=0;
 662
 663 #ifdef LISP_FEATURE_SB_SAFEPOINT
 664 # ifdef LISP_FEATURE_WIN32
 665     th->carried_base_pointer = 0;
 666 # endif
 667 # ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
 668     th->pc_around_foreign_call = 0;
 669 # endif
 670     th->csp_around_foreign_call = csp_page;
 671 #endif
 672
 673 #ifdef LISP_FEATURE_SB_THREAD
 674     /* Contrary to the "allocate all the spaces at once" comment above,
 675      * the os_attr is allocated separately.  We cannot put it into the
 676      * nonpointer data, because it's used for post_mortem and freed
 677      * separately */
 678     th->os_attr=malloc(sizeof(pthread_attr_t));
 679     th->nonpointer_data = nonpointer_data;
 680 # ifndef LISP_FEATURE_SB_SAFEPOINT
 681     th->state_sem=&nonpointer_data->state_sem;
 682     th->state_not_running_sem=&nonpointer_data->state_not_running_sem;
 683     th->state_not_stopped_sem=&nonpointer_data->state_not_stopped_sem;
 684     os_sem_init(th->state_sem, 1);
 685     os_sem_init(th->state_not_running_sem, 0);
 686     os_sem_init(th->state_not_stopped_sem, 0);
 687 # endif
 688     th->state_not_running_waitcount = 0;
 689     th->state_not_stopped_waitcount = 0;
 690 #endif
 691     th->state=STATE_RUNNING;
 692 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
 693     th->alien_stack_pointer=((void *)th->alien_stack_start
 694                              + ALIEN_STACK_SIZE-N_WORD_BYTES);
 695 #else
 696     th->alien_stack_pointer=((void *)th->alien_stack_start);
 697 #endif
 698 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64) || defined(LISP_FEATURE_SB_THREAD)
 699     th->pseudo_atomic_bits=0;
 700 #endif
 701 #ifdef LISP_FEATURE_GENCGC
 702     gc_set_region_empty(&th->alloc_region);
 703 #endif
 704 #ifdef LISP_FEATURE_SB_THREAD
 705     /* This parallels the same logic in globals.c for the
 706      * single-threaded foreign_function_call_active, KLUDGE and
 707      * all. */
 708 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 709     th->foreign_function_call_active = 0;
 710 #else
 711     th->foreign_function_call_active = 1;
 712 #endif
 713 #endif
 714
 715 #ifndef LISP_FEATURE_SB_THREAD
 716     /* the tls-points-into-struct-thread trick is only good for threaded
 717      * sbcl, because unithread sbcl doesn't have tls.  So, we copy the
 718      * appropriate values from struct thread here, and make sure that
 719      * we use the appropriate SymbolValue macros to access any of the
 720      * variable quantities from the C runtime.  It's not quite OAOOM,
 721      * it just feels like it */
 722     SetSymbolValue(BINDING_STACK_START,(lispobj)th->binding_stack_start,th);
 723     SetSymbolValue(CONTROL_STACK_START,(lispobj)th->control_stack_start,th);
 724     SetSymbolValue(CONTROL_STACK_END,(lispobj)th->control_stack_end,th);
 725 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
 726     SetSymbolValue(ALIEN_STACK,(lispobj)th->alien_stack_pointer,th);
 727     SetSymbolValue(PSEUDO_ATOMIC_BITS,(lispobj)th->pseudo_atomic_bits,th);
 728 #endif
 729 #endif
 730     bind_variable(CURRENT_CATCH_BLOCK,make_fixnum(0),th);
 731     bind_variable(CURRENT_UNWIND_PROTECT_BLOCK,make_fixnum(0),th);
 732     bind_variable(FREE_INTERRUPT_CONTEXT_INDEX,make_fixnum(0),th);
 733     bind_variable(INTERRUPT_PENDING, NIL,th);
 734     bind_variable(INTERRUPTS_ENABLED,T,th);
 735     bind_variable(ALLOW_WITH_INTERRUPTS,T,th);
 736     bind_variable(GC_PENDING,NIL,th);
 737     bind_variable(ALLOC_SIGNAL,NIL,th);
 738 #ifdef PINNED_OBJECTS
 739     bind_variable(PINNED_OBJECTS,NIL,th);
 740 #endif
 741 #ifdef LISP_FEATURE_SB_THREAD
 742     bind_variable(STOP_FOR_GC_PENDING,NIL,th);
 743 #endif
 744 #if defined(LISP_FEATURE_SB_SAFEPOINT)
 745     bind_variable(GC_SAFE,NIL,th);
 746     bind_variable(IN_SAFEPOINT,NIL,th);
 747 #endif
 748 #ifdef LISP_FEATURE_SB_THRUPTION
 749     bind_variable(THRUPTION_PENDING,NIL,th);
 750     bind_variable(RESTART_CLUSTERS,NIL,th);
 751 #endif
 752 #ifndef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
 753     access_control_stack_pointer(th)=th->control_stack_start;
 754 #endif
 755
 756 #if defined(LISP_FEATURE_WIN32)
 757     th->interrupt_data = (struct interrupt_data *)
 758         calloc((sizeof (struct interrupt_data)),1);
 759 #else
 760     th->interrupt_data = (struct interrupt_data *)
 761         os_validate(0,(sizeof (struct interrupt_data)));
 762 #endif
 763     if (!th->interrupt_data) {
 764         free_thread_struct(th);
 765         return 0;
 766     }
 767     th->interrupt_data->pending_handler = 0;
 768     th->interrupt_data->gc_blocked_deferrables = 0;
 769 #ifdef GENCGC_IS_PRECISE
 770     th->interrupt_data->allocation_trap_context = 0;
 771 #endif
 772     th->no_tls_value_marker=initial_function;
 773
 774 #if defined(LISP_FEATURE_WIN32)
 775     for (i = 0; i<sizeof(th->private_events.events)/
 776            sizeof(th->private_events.events[0]); ++i) {
 777       th->private_events.events[i] = CreateEvent(NULL,FALSE,FALSE,NULL);
 778     }
 779     th->synchronous_io_handle_and_flag = 0;
 780 #endif
 781     th->stepping = NIL;
 782     return th;
 783 }
 784
 785 void create_initial_thread(lispobj initial_function) {
 786     struct thread *th=create_thread_struct(initial_function);
 787 #ifdef LISP_FEATURE_SB_THREAD
 788     pthread_key_create(&lisp_thread, 0);
 789 #endif
 790     if(th) {
 791         initial_thread_trampoline(th); /* no return */
 792     } else lose("can't create initial thread\n");
 793 }
 794
 795 #ifdef LISP_FEATURE_SB_THREAD
 796
 797 #ifndef __USE_XOPEN2K
 798 extern int pthread_attr_setstack (pthread_attr_t *__attr, void *__stackaddr,
 799                                   size_t __stacksize);
 800 #endif
 801
 802 boolean create_os_thread(struct thread *th,os_thread_t *kid_tid)
 803 {
 804     /* The new thread inherits the restrictive signal mask set here,
 805      * and enables signals again when it is set up properly. */
 806     sigset_t oldset;
 807     boolean r=1;
 808     int retcode = 0, initcode;
 809
 810     FSHOW_SIGNAL((stderr,"/create_os_thread: creating new thread\n"));
 811
 812     /* Blocking deferrable signals is enough, no need to block
 813      * SIG_STOP_FOR_GC because the child process is not linked onto
 814      * all_threads until it's ready. */
 815     block_deferrable_signals(0, &oldset);
 816
 817 #ifdef LOCK_CREATE_THREAD
 818     retcode = pthread_mutex_lock(&create_thread_lock);
 819     gc_assert(retcode == 0);
 820     FSHOW_SIGNAL((stderr,"/create_os_thread: got lock\n"));
 821 #endif
 822
 823     if((initcode = pthread_attr_init(th->os_attr)) ||
 824        /* call_into_lisp_first_time switches the stack for the initial
 825         * thread. For the others, we use this. */
 826 #if defined(LISP_FEATURE_WIN32)
 827        (pthread_attr_setstacksize(th->os_attr, thread_control_stack_size)) ||
 828 #else
 829        (pthread_attr_setstack(th->os_attr,th->control_stack_start,
 830                               thread_control_stack_size)) ||
 831 #endif
 832        (retcode = pthread_create
 833         (kid_tid,th->os_attr,(void *(*)(void *))new_thread_trampoline,th))) {
 834         FSHOW_SIGNAL((stderr, "init = %d\n", initcode));
 835         FSHOW_SIGNAL((stderr, "pthread_create returned %d, errno %d\n",
 836                       retcode, errno));
 837         if(retcode < 0) {
 838             perror("create_os_thread");
 839         }
 840         r=0;
 841     }
 842
 843 #ifdef LOCK_CREATE_THREAD
 844     retcode = pthread_mutex_unlock(&create_thread_lock);
 845     gc_assert(retcode == 0);
 846     FSHOW_SIGNAL((stderr,"/create_os_thread: released lock\n"));
 847 #endif
 848     thread_sigmask(SIG_SETMASK,&oldset,0);
 849     return r;
 850 }
 851
 852 os_thread_t create_thread(lispobj initial_function) {
 853     struct thread *th, *thread = arch_os_get_current_thread();
 854     os_thread_t kid_tid = 0;
 855
 856     /* Must defend against async unwinds. */
 857     if (SymbolValue(INTERRUPTS_ENABLED, thread) != NIL)
 858         lose("create_thread is not safe when interrupts are enabled.\n");
 859
 860     /* Assuming that a fresh thread struct has no lisp objects in it,
 861      * linking it to all_threads can be left to the thread itself
 862      * without fear of gc lossage. initial_function violates this
 863      * assumption and must stay pinned until the child starts up. */
 864     th = create_thread_struct(initial_function);
 865     if (th && !create_os_thread(th,&kid_tid)) {
 866         free_thread_struct(th);
 867         kid_tid = 0;
 868     }
 869     return kid_tid;
 870 }
 871
 872 /* stopping the world is a two-stage process.  From this thread we signal
 873  * all the others with SIG_STOP_FOR_GC.  The handler for this signal does
 874  * the usual pseudo-atomic checks (we don't want to stop a thread while
 875  * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC.
 876  */
 877 /*
 878  * (With SB-SAFEPOINT, see the definitions in safepoint.c instead.)
 879  */
 880 #ifndef LISP_FEATURE_SB_SAFEPOINT
 881
 882 /* To avoid deadlocks when gc stops the world all clients of each
 883  * mutex must enable or disable SIG_STOP_FOR_GC for the duration of
 884  * holding the lock, but they must agree on which. */
 885 void gc_stop_the_world()
 886 {
 887     struct thread *p,*th=arch_os_get_current_thread();
 888     int status, lock_ret;
 889 #ifdef LOCK_CREATE_THREAD
 890     /* KLUDGE: Stopping the thread during pthread_create() causes deadlock
 891      * on FreeBSD. */
 892     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:waiting on create_thread_lock\n"));
 893     lock_ret = pthread_mutex_lock(&create_thread_lock);
 894     gc_assert(lock_ret == 0);
 895     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:got create_thread_lock\n"));
 896 #endif
 897     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:waiting on lock\n"));
 898     /* keep threads from starting while the world is stopped. */
 899     lock_ret = pthread_mutex_lock(&all_threads_lock);      \
 900     gc_assert(lock_ret == 0);
 901
 902     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:got lock\n"));
 903     /* stop all other threads by sending them SIG_STOP_FOR_GC */
 904     for(p=all_threads; p; p=p->next) {
 905         gc_assert(p->os_thread != 0);
 906         FSHOW_SIGNAL((stderr,"/gc_stop_the_world: thread=%lu, state=%x\n",
 907                       p->os_thread, thread_state(p)));
 908         if((p!=th) && ((thread_state(p)==STATE_RUNNING))) {
 909             FSHOW_SIGNAL((stderr,"/gc_stop_the_world: suspending thread %lu\n",
 910                           p->os_thread));
 911             /* We already hold all_thread_lock, P can become DEAD but
 912              * cannot exit, ergo it's safe to use pthread_kill. */
 913             status=pthread_kill(p->os_thread,SIG_STOP_FOR_GC);
 914             if (status==ESRCH) {
 915                 /* This thread has exited. */
 916                 gc_assert(thread_state(p)==STATE_DEAD);
 917             } else if (status) {
 918                 lose("cannot send suspend thread=%lu: %d, %s\n",
 919                      p->os_thread,status,strerror(status));
 920             }
 921         }
 922     }
 923     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:signals sent\n"));
 924     for(p=all_threads;p;p=p->next) {
 925         if (p!=th) {
 926             FSHOW_SIGNAL
 927                 ((stderr,
 928                   "/gc_stop_the_world: waiting for thread=%lu: state=%x\n",
 929                   p->os_thread, thread_state(p)));
 930             wait_for_thread_state_change(p, STATE_RUNNING);
 931             if (p->state == STATE_RUNNING)
 932                 lose("/gc_stop_the_world: unexpected state");
 933         }
 934     }
 935     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:end\n"));
 936 }
 937
 938 void gc_start_the_world()
 939 {
 940     struct thread *p,*th=arch_os_get_current_thread();
 941     int lock_ret;
 942     /* if a resumed thread creates a new thread before we're done with
 943      * this loop, the new thread will get consed on the front of
 944      * all_threads, but it won't have been stopped so won't need
 945      * restarting */
 946     FSHOW_SIGNAL((stderr,"/gc_start_the_world:begin\n"));
 947     for(p=all_threads;p;p=p->next) {
 948         gc_assert(p->os_thread!=0);
 949         if (p!=th) {
 950             lispobj state = thread_state(p);
 951             if (state != STATE_DEAD) {
 952                 if(state != STATE_STOPPED) {
 953                     lose("gc_start_the_world: wrong thread state is %d\n",
 954                          fixnum_value(state));
 955                 }
 956                 FSHOW_SIGNAL((stderr, "/gc_start_the_world: resuming %lu\n",
 957                               p->os_thread));
 958                 set_thread_state(p, STATE_RUNNING);
 959             }
 960         }
 961     }
 962
 963     lock_ret = pthread_mutex_unlock(&all_threads_lock);
 964     gc_assert(lock_ret == 0);
 965 #ifdef LOCK_CREATE_THREAD
 966     lock_ret = pthread_mutex_unlock(&create_thread_lock);
 967     gc_assert(lock_ret == 0);
 968 #endif
 969
 970     FSHOW_SIGNAL((stderr,"/gc_start_the_world:end\n"));
 971 }
 972
 973 #endif /* !LISP_FEATURE_SB_SAFEPOINT */
 974 #endif /* !LISP_FEATURE_SB_THREAD */
 975
 976 int
 977 thread_yield()
 978 {
 979 #ifdef LISP_FEATURE_SB_THREAD
 980     return sched_yield();
 981 #else
 982     return 0;
 983 #endif
 984 }
 985
 986 int
 987 wake_thread(os_thread_t os_thread)
 988 {
 989 #if defined(LISP_FEATURE_WIN32)
 990     return kill_safely(os_thread, 1);
 991 #elif !defined(LISP_FEATURE_SB_THRUPTION)
 992     return kill_safely(os_thread, SIGPIPE);
 993 #else
 994     return wake_thread_posix(os_thread);
 995 #endif
 996 }
 997
 998 /* If the thread id given does not belong to a running thread (it has
 999  * exited or never even existed) pthread_kill _may_ fail with ESRCH,
1000  * but it is also allowed to just segfault, see
1001  * <http://udrepper.livejournal.com/16844.html>.
1002  *
1003  * Relying on thread ids can easily backfire since ids are recycled
1004  * (NPTL recycles them extremely fast) so a signal can be sent to
1005  * another process if the one it was sent to exited.
1006  *
1007  * For these reasons, we must make sure that the thread is still alive
1008  * when the pthread_kill is called and return if the thread is
1009  * exiting.
1010  *
1011  * Note (DFL, 2011-06-22): At the time of writing, this function is only
1012  * used for INTERRUPT-THREAD, hence the wake_thread special-case for
1013  * Windows is OK. */
1014 int
1015 kill_safely(os_thread_t os_thread, int signal)
1016 {
1017     FSHOW_SIGNAL((stderr,"/kill_safely: %lu, %d\n", os_thread, signal));
1018     {
1019 #ifdef LISP_FEATURE_SB_THREAD
1020         sigset_t oldset;
1021         struct thread *thread;
1022         /* Frequent special case: resignalling to self.  The idea is
1023          * that leave_region safepoint will acknowledge the signal, so
1024          * there is no need to take locks, roll thread to safepoint
1025          * etc. */
1026         /* Kludge (on safepoint builds): At the moment, this isn't just
1027          * an optimization; rather it masks the fact that
1028          * gc_stop_the_world() grabs the all_threads mutex without
1029          * releasing it, and since we're not using recursive pthread
1030          * mutexes, the pthread_mutex_lock() around the all_threads loop
1031          * would go wrong.  Why are we running interruptions while
1032          * stopping the world though?  Test case is (:ASYNC-UNWIND
1033          * :SPECIALS), especially with s/10/100/ in both loops. */
1034         if (os_thread == pthread_self()) {
1035             pthread_kill(os_thread, signal);
1036 #ifdef LISP_FEATURE_WIN32
1037             check_pending_thruptions(NULL);
1038 #endif
1039             return 0;
1040         }
1041
1042         /* pthread_kill is not async signal safe and we don't want to be
1043          * interrupted while holding the lock. */
1044         block_deferrable_signals(0, &oldset);
1045         pthread_mutex_lock(&all_threads_lock);
1046         for (thread = all_threads; thread; thread = thread->next) {
1047             if (thread->os_thread == os_thread) {
1048                 int status = pthread_kill(os_thread, signal);
1049                 if (status)
1050                     lose("kill_safely: pthread_kill failed with %d\n", status);
1051 #if defined(LISP_FEATURE_WIN32) && defined(LISP_FEATURE_SB_THRUPTION)
1052                 wake_thread_win32(thread);
1053 #endif
1054                 break;
1055             }
1056         }
1057         pthread_mutex_unlock(&all_threads_lock);
1058         thread_sigmask(SIG_SETMASK,&oldset,0);
1059         if (thread)
1060             return 0;
1061         else
1062             return -1;
1063 #elif defined(LISP_FEATURE_WIN32)
1064         return 0;
1065 #else
1066         int status;
1067         if (os_thread != 0)
1068             lose("kill_safely: who do you want to kill? %d?\n", os_thread);
1069         /* Dubious (as in don't know why it works) workaround for the
1070          * signal sometimes not being generated on darwin. */
1071 #ifdef LISP_FEATURE_DARWIN
1072         {
1073             sigset_t oldset;
1074             sigprocmask(SIG_BLOCK, &deferrable_sigset, &oldset);
1075             status = raise(signal);
1076             sigprocmask(SIG_SETMASK,&oldset,0);
1077         }
1078 #else
1079         status = raise(signal);
1080 #endif
1081         if (status == 0) {
1082             return 0;
1083         } else {
1084             lose("cannot raise signal %d, %d %s\n",
1085                  signal, status, strerror(errno));
1086         }
1087 #endif
1088     }
1089 }