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 #if defined(LISP_FEATURE_SB_SAFEPOINT_STRICTLY) && !defined(LISP_FEATURE_WIN32)
 405     gc_alloc_update_page_tables(BOXED_PAGE_FLAG, &th->sprof_alloc_region);
 406 #endif
 407     pop_gcing_safety(&scribble->safety);
 408     lock_ret = pthread_mutex_lock(&all_threads_lock);
 409     gc_assert(lock_ret == 0);
 410     unlink_thread(th);
 411     lock_ret = pthread_mutex_unlock(&all_threads_lock);
 412     gc_assert(lock_ret == 0);
 413 #else
 414     /* Block GC */
 415     block_blockable_signals(0, 0);
 416     set_thread_state(th, STATE_DEAD);
 417
 418     /* SIG_STOP_FOR_GC is blocked and GC might be waiting for this
 419      * thread, but since we are already dead it won't wait long. */
 420     lock_ret = pthread_mutex_lock(&all_threads_lock);
 421     gc_assert(lock_ret == 0);
 422
 423     gc_alloc_update_page_tables(BOXED_PAGE_FLAG, &th->alloc_region);
 424 #if defined(LISP_FEATURE_SB_SAFEPOINT_STRICTLY) && !defined(LISP_FEATURE_WIN32)
 425     gc_alloc_update_page_tables(BOXED_PAGE_FLAG, &th->sprof_alloc_region);
 426 #endif
 427     unlink_thread(th);
 428     pthread_mutex_unlock(&all_threads_lock);
 429     gc_assert(lock_ret == 0);
 430 #endif
 431
 432     if(th->tls_cookie>=0) arch_os_thread_cleanup(th);
 433 #ifndef LISP_FEATURE_SB_SAFEPOINT
 434     os_sem_destroy(th->state_sem);
 435     os_sem_destroy(th->state_not_running_sem);
 436     os_sem_destroy(th->state_not_stopped_sem);
 437 #endif
 438
 439 #if defined(LISP_FEATURE_WIN32)
 440     free((os_vm_address_t)th->interrupt_data);
 441 #else
 442     os_invalidate((os_vm_address_t)th->interrupt_data,
 443                   (sizeof (struct interrupt_data)));
 444 #endif
 445
 446 #ifdef LISP_FEATURE_MACH_EXCEPTION_HANDLER
 447     mach_lisp_thread_destroy(th);
 448 #endif
 449
 450 #if defined(LISP_FEATURE_WIN32)
 451     int i;
 452     for (i = 0; i<
 453              (int) (sizeof(th->private_events.events)/
 454                     sizeof(th->private_events.events[0])); ++i) {
 455       CloseHandle(th->private_events.events[i]);
 456     }
 457     TlsSetValue(OUR_TLS_INDEX,NULL);
 458 #endif
 459
 460     /* Undo the association of the current pthread to its `struct thread',
 461      * such that we can call arch_os_get_current_thread() later in this
 462      * thread and cleanly get back NULL. */
 463 #ifdef LISP_FEATURE_GCC_TLS
 464     current_thread = NULL;
 465 #else
 466     pthread_setspecific(specials, NULL);
 467 #endif
 468
 469     schedule_thread_post_mortem(th);
 470 }
 471
 472 /* this is the first thing that runs in the child (which is why the
 473  * silly calling convention).  Basically it calls the user's requested
 474  * lisp function after doing arch_os_thread_init and whatever other
 475  * bookkeeping needs to be done
 476  */
 477 int
 478 new_thread_trampoline(struct thread *th)
 479 {
 480     int result;
 481     init_thread_data scribble;
 482
 483     FSHOW((stderr,"/creating thread %lu\n", thread_self()));
 484     check_deferrables_blocked_or_lose(0);
 485 #ifndef LISP_FEATURE_SB_SAFEPOINT
 486     check_gc_signals_unblocked_or_lose(0);
 487 #endif
 488
 489     lispobj function = th->no_tls_value_marker;
 490     th->no_tls_value_marker = NO_TLS_VALUE_MARKER_WIDETAG;
 491     init_new_thread(th, &scribble, 1);
 492     result = funcall0(function);
 493     undo_init_new_thread(th, &scribble);
 494
 495     FSHOW((stderr,"/exiting thread %lu\n", thread_self()));
 496     return result;
 497 }
 498
 499 # ifdef LISP_FEATURE_SB_SAFEPOINT
 500 static struct thread *create_thread_struct(lispobj);
 501
 502 void
 503 attach_os_thread(init_thread_data *scribble)
 504 {
 505     os_thread_t os = pthread_self();
 506     odxprint(misc, "attach_os_thread: attaching to %p", os);
 507
 508     struct thread *th = create_thread_struct(NIL);
 509     block_deferrable_signals(0, &scribble->oldset);
 510     th->no_tls_value_marker = NO_TLS_VALUE_MARKER_WIDETAG;
 511     /* We don't actually want a pthread_attr here, but rather than add
 512      * `if's to the post-mostem, let's just keep that code happy by
 513      * keeping it initialized: */
 514     pthread_attr_init(th->os_attr);
 515
 516 #ifndef LISP_FEATURE_WIN32
 517     /* On windows, arch_os_thread_init will take care of finding the
 518      * stack. */
 519     pthread_attr_t attr;
 520     int pthread_getattr_np(pthread_t, pthread_attr_t *);
 521     pthread_getattr_np(os, &attr);
 522     void *stack_addr;
 523     size_t stack_size;
 524     pthread_attr_getstack(&attr, &stack_addr, &stack_size);
 525     th->control_stack_start = stack_addr;
 526     th->control_stack_end = (void *) (((uintptr_t) stack_addr) + stack_size);
 527 #endif
 528
 529     init_new_thread(th, scribble, 0);
 530
 531     /* We will be calling into Lisp soon, and the functions being called
 532      * recklessly ignore the comment in target-thread which says that we
 533      * must be careful to not cause GC while initializing a new thread.
 534      * Since we first need to create a fresh thread object, it's really
 535      * tempting to just perform such unsafe allocation though.  So let's
 536      * at least try to suppress GC before consing, and hope that it
 537      * works: */
 538     bind_variable(GC_INHIBIT, T, th);
 539
 540     uword_t stacksize
 541         = (uword_t) th->control_stack_end - (uword_t) th->control_stack_start;
 542     odxprint(misc, "attach_os_thread: attached %p as %p (0x%lx bytes stack)",
 543              os, th, (long) stacksize);
 544 }
 545
 546 void
 547 detach_os_thread(init_thread_data *scribble)
 548 {
 549     struct thread *th = arch_os_get_current_thread();
 550     odxprint(misc, "detach_os_thread: detaching");
 551
 552     undo_init_new_thread(th, scribble);
 553
 554     odxprint(misc, "deattach_os_thread: detached");
 555     pthread_setspecific(lisp_thread, (void *)0);
 556     thread_sigmask(SIG_SETMASK, &scribble->oldset, 0);
 557 }
 558 # endif /* safepoint */
 559
 560 #endif /* LISP_FEATURE_SB_THREAD */
 561
 562 static void
 563 free_thread_struct(struct thread *th)
 564 {
 565 #if defined(LISP_FEATURE_WIN32)
 566     if (th->interrupt_data) {
 567         os_invalidate_free((os_vm_address_t) th->interrupt_data,
 568                       (sizeof (struct interrupt_data)));
 569     }
 570     os_invalidate_free((os_vm_address_t) th->os_address,
 571                   THREAD_STRUCT_SIZE);
 572 #else
 573     if (th->interrupt_data)
 574         os_invalidate((os_vm_address_t) th->interrupt_data,
 575                       (sizeof (struct interrupt_data)));
 576     os_invalidate((os_vm_address_t) th->os_address,
 577                   THREAD_STRUCT_SIZE);
 578 #endif
 579 }
 580
 581 #ifdef LISP_FEATURE_SB_THREAD
 582 /* FIXME: should be MAX_INTERRUPTS -1 ? */
 583 const unsigned int tls_index_start =
 584   MAX_INTERRUPTS + sizeof(struct thread)/sizeof(lispobj);
 585 #endif
 586
 587 /* this is called from any other thread to create the new one, and
 588  * initialize all parts of it that can be initialized from another
 589  * thread
 590  */
 591
 592 static struct thread *
 593 create_thread_struct(lispobj initial_function) {
 594     union per_thread_data *per_thread;
 595     struct thread *th=0;        /*  subdue gcc */
 596     void *spaces=0;
 597     void *aligned_spaces=0;
 598 #if defined(LISP_FEATURE_SB_THREAD) || defined(LISP_FEATURE_WIN32)
 599     unsigned int i;
 600 #endif
 601
 602     /* May as well allocate all the spaces at once: it saves us from
 603      * having to decide what to do if only some of the allocations
 604      * succeed. SPACES must be appropriately aligned, since the GC
 605      * expects the control stack to start at a page boundary -- and
 606      * the OS may have even more rigorous requirements. We can't rely
 607      * on the alignment passed from os_validate, since that might
 608      * assume the current (e.g. 4k) pagesize, while we calculate with
 609      * the biggest (e.g. 64k) pagesize allowed by the ABI. */
 610     spaces=os_validate(0, THREAD_STRUCT_SIZE);
 611     if(!spaces)
 612         return NULL;
 613     /* Aligning up is safe as THREAD_STRUCT_SIZE has
 614      * THREAD_ALIGNMENT_BYTES padding. */
 615     aligned_spaces = (void *)((((uword_t)(char *)spaces)
 616                                + THREAD_ALIGNMENT_BYTES-1)
 617                               &~(uword_t)(THREAD_ALIGNMENT_BYTES-1));
 618     void* csp_page=
 619         (aligned_spaces+
 620          thread_control_stack_size+
 621          BINDING_STACK_SIZE+
 622          ALIEN_STACK_SIZE);
 623     per_thread=(union per_thread_data *)
 624         (csp_page + THREAD_CSP_PAGE_SIZE);
 625     struct nonpointer_thread_data *nonpointer_data
 626         = (void *) &per_thread->dynamic_values[TLS_SIZE];
 627
 628 #ifdef LISP_FEATURE_SB_THREAD
 629     for(i = 0; i < (dynamic_values_bytes / sizeof(lispobj)); i++)
 630         per_thread->dynamic_values[i] = NO_TLS_VALUE_MARKER_WIDETAG;
 631     if (all_threads == 0) {
 632         if(SymbolValue(FREE_TLS_INDEX,0)==UNBOUND_MARKER_WIDETAG) {
 633             SetSymbolValue(FREE_TLS_INDEX,tls_index_start << WORD_SHIFT,0);
 634             SetSymbolValue(TLS_INDEX_LOCK,make_fixnum(0),0);
 635         }
 636 #define STATIC_TLS_INIT(sym,field) \
 637   ((struct symbol *)(sym-OTHER_POINTER_LOWTAG))->tls_index= \
 638   (THREAD_SLOT_OFFSET_WORDS(field) << WORD_SHIFT)
 639
 640         STATIC_TLS_INIT(BINDING_STACK_START,binding_stack_start);
 641 #ifdef BINDING_STACK_POINTER
 642         STATIC_TLS_INIT(BINDING_STACK_POINTER,binding_stack_pointer);
 643 #endif
 644         STATIC_TLS_INIT(CONTROL_STACK_START,control_stack_start);
 645         STATIC_TLS_INIT(CONTROL_STACK_END,control_stack_end);
 646 #ifdef ALIEN_STACK
 647         STATIC_TLS_INIT(ALIEN_STACK,alien_stack_pointer);
 648 #endif
 649 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
 650         STATIC_TLS_INIT(PSEUDO_ATOMIC_BITS,pseudo_atomic_bits);
 651 #endif
 652 #undef STATIC_TLS_INIT
 653     }
 654 #endif
 655
 656     th=&per_thread->thread;
 657     th->os_address = spaces;
 658     th->control_stack_start = aligned_spaces;
 659     th->binding_stack_start=
 660         (lispobj*)((void*)th->control_stack_start+thread_control_stack_size);
 661     th->control_stack_end = th->binding_stack_start;
 662     th->control_stack_guard_page_protected = T;
 663     th->alien_stack_start=
 664         (lispobj*)((void*)th->binding_stack_start+BINDING_STACK_SIZE);
 665     set_binding_stack_pointer(th,th->binding_stack_start);
 666     th->this=th;
 667     th->os_thread=0;
 668
 669 #ifdef LISP_FEATURE_SB_SAFEPOINT
 670 # ifdef LISP_FEATURE_WIN32
 671     th->carried_base_pointer = 0;
 672 # endif
 673 # ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
 674     th->pc_around_foreign_call = 0;
 675 # endif
 676     th->csp_around_foreign_call = csp_page;
 677 #endif
 678
 679 #ifdef LISP_FEATURE_SB_THREAD
 680     /* Contrary to the "allocate all the spaces at once" comment above,
 681      * the os_attr is allocated separately.  We cannot put it into the
 682      * nonpointer data, because it's used for post_mortem and freed
 683      * separately */
 684     th->os_attr=malloc(sizeof(pthread_attr_t));
 685     th->nonpointer_data = nonpointer_data;
 686 # ifndef LISP_FEATURE_SB_SAFEPOINT
 687     th->state_sem=&nonpointer_data->state_sem;
 688     th->state_not_running_sem=&nonpointer_data->state_not_running_sem;
 689     th->state_not_stopped_sem=&nonpointer_data->state_not_stopped_sem;
 690     os_sem_init(th->state_sem, 1);
 691     os_sem_init(th->state_not_running_sem, 0);
 692     os_sem_init(th->state_not_stopped_sem, 0);
 693 # endif
 694     th->state_not_running_waitcount = 0;
 695     th->state_not_stopped_waitcount = 0;
 696 #endif
 697     th->state=STATE_RUNNING;
 698 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
 699     th->alien_stack_pointer=((void *)th->alien_stack_start
 700                              + ALIEN_STACK_SIZE-N_WORD_BYTES);
 701 #else
 702     th->alien_stack_pointer=((void *)th->alien_stack_start);
 703 #endif
 704 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64) || defined(LISP_FEATURE_SB_THREAD)
 705     th->pseudo_atomic_bits=0;
 706 #endif
 707 #ifdef LISP_FEATURE_GENCGC
 708     gc_set_region_empty(&th->alloc_region);
 709 # if defined(LISP_FEATURE_SB_SAFEPOINT_STRICTLY) && !defined(LISP_FEATURE_WIN32)
 710     gc_set_region_empty(&th->sprof_alloc_region);
 711 # endif
 712 #endif
 713 #ifdef LISP_FEATURE_SB_THREAD
 714     /* This parallels the same logic in globals.c for the
 715      * single-threaded foreign_function_call_active, KLUDGE and
 716      * all. */
 717 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 718     th->foreign_function_call_active = 0;
 719 #else
 720     th->foreign_function_call_active = 1;
 721 #endif
 722 #endif
 723
 724 #ifndef LISP_FEATURE_SB_THREAD
 725     /* the tls-points-into-struct-thread trick is only good for threaded
 726      * sbcl, because unithread sbcl doesn't have tls.  So, we copy the
 727      * appropriate values from struct thread here, and make sure that
 728      * we use the appropriate SymbolValue macros to access any of the
 729      * variable quantities from the C runtime.  It's not quite OAOOM,
 730      * it just feels like it */
 731     SetSymbolValue(BINDING_STACK_START,(lispobj)th->binding_stack_start,th);
 732     SetSymbolValue(CONTROL_STACK_START,(lispobj)th->control_stack_start,th);
 733     SetSymbolValue(CONTROL_STACK_END,(lispobj)th->control_stack_end,th);
 734 #if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64)
 735     SetSymbolValue(ALIEN_STACK,(lispobj)th->alien_stack_pointer,th);
 736     SetSymbolValue(PSEUDO_ATOMIC_BITS,(lispobj)th->pseudo_atomic_bits,th);
 737 #endif
 738 #endif
 739     bind_variable(CURRENT_CATCH_BLOCK,make_fixnum(0),th);
 740     bind_variable(CURRENT_UNWIND_PROTECT_BLOCK,make_fixnum(0),th);
 741     bind_variable(FREE_INTERRUPT_CONTEXT_INDEX,make_fixnum(0),th);
 742     bind_variable(INTERRUPT_PENDING, NIL,th);
 743     bind_variable(INTERRUPTS_ENABLED,T,th);
 744     bind_variable(ALLOW_WITH_INTERRUPTS,T,th);
 745     bind_variable(GC_PENDING,NIL,th);
 746     bind_variable(ALLOC_SIGNAL,NIL,th);
 747 #ifdef PINNED_OBJECTS
 748     bind_variable(PINNED_OBJECTS,NIL,th);
 749 #endif
 750 #ifdef LISP_FEATURE_SB_THREAD
 751     bind_variable(STOP_FOR_GC_PENDING,NIL,th);
 752 #endif
 753 #if defined(LISP_FEATURE_SB_SAFEPOINT)
 754     bind_variable(GC_SAFE,NIL,th);
 755     bind_variable(IN_SAFEPOINT,NIL,th);
 756 #endif
 757 #ifdef LISP_FEATURE_SB_THRUPTION
 758     bind_variable(THRUPTION_PENDING,NIL,th);
 759     bind_variable(RESTART_CLUSTERS,NIL,th);
 760 #endif
 761 #ifndef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
 762     access_control_stack_pointer(th)=th->control_stack_start;
 763 #endif
 764
 765 #if defined(LISP_FEATURE_WIN32)
 766     th->interrupt_data = (struct interrupt_data *)
 767         calloc((sizeof (struct interrupt_data)),1);
 768 #else
 769     th->interrupt_data = (struct interrupt_data *)
 770         os_validate(0,(sizeof (struct interrupt_data)));
 771 #endif
 772     if (!th->interrupt_data) {
 773         free_thread_struct(th);
 774         return 0;
 775     }
 776     th->interrupt_data->pending_handler = 0;
 777     th->interrupt_data->gc_blocked_deferrables = 0;
 778 #ifdef GENCGC_IS_PRECISE
 779     th->interrupt_data->allocation_trap_context = 0;
 780 #endif
 781     th->no_tls_value_marker=initial_function;
 782
 783 #if defined(LISP_FEATURE_WIN32)
 784     for (i = 0; i<sizeof(th->private_events.events)/
 785            sizeof(th->private_events.events[0]); ++i) {
 786       th->private_events.events[i] = CreateEvent(NULL,FALSE,FALSE,NULL);
 787     }
 788     th->synchronous_io_handle_and_flag = 0;
 789 #endif
 790     th->stepping = NIL;
 791     return th;
 792 }
 793
 794 void create_initial_thread(lispobj initial_function) {
 795     struct thread *th=create_thread_struct(initial_function);
 796 #ifdef LISP_FEATURE_SB_THREAD
 797     pthread_key_create(&lisp_thread, 0);
 798 #endif
 799     if(th) {
 800         initial_thread_trampoline(th); /* no return */
 801     } else lose("can't create initial thread\n");
 802 }
 803
 804 #ifdef LISP_FEATURE_SB_THREAD
 805
 806 #ifndef __USE_XOPEN2K
 807 extern int pthread_attr_setstack (pthread_attr_t *__attr, void *__stackaddr,
 808                                   size_t __stacksize);
 809 #endif
 810
 811 boolean create_os_thread(struct thread *th,os_thread_t *kid_tid)
 812 {
 813     /* The new thread inherits the restrictive signal mask set here,
 814      * and enables signals again when it is set up properly. */
 815     sigset_t oldset;
 816     boolean r=1;
 817     int retcode = 0, initcode;
 818
 819     FSHOW_SIGNAL((stderr,"/create_os_thread: creating new thread\n"));
 820
 821     /* Blocking deferrable signals is enough, no need to block
 822      * SIG_STOP_FOR_GC because the child process is not linked onto
 823      * all_threads until it's ready. */
 824     block_deferrable_signals(0, &oldset);
 825
 826 #ifdef LOCK_CREATE_THREAD
 827     retcode = pthread_mutex_lock(&create_thread_lock);
 828     gc_assert(retcode == 0);
 829     FSHOW_SIGNAL((stderr,"/create_os_thread: got lock\n"));
 830 #endif
 831
 832     if((initcode = pthread_attr_init(th->os_attr)) ||
 833        /* call_into_lisp_first_time switches the stack for the initial
 834         * thread. For the others, we use this. */
 835 #if defined(LISP_FEATURE_WIN32)
 836        (pthread_attr_setstacksize(th->os_attr, thread_control_stack_size)) ||
 837 #else
 838        (pthread_attr_setstack(th->os_attr,th->control_stack_start,
 839                               thread_control_stack_size)) ||
 840 #endif
 841        (retcode = pthread_create
 842         (kid_tid,th->os_attr,(void *(*)(void *))new_thread_trampoline,th))) {
 843         FSHOW_SIGNAL((stderr, "init = %d\n", initcode));
 844         FSHOW_SIGNAL((stderr, "pthread_create returned %d, errno %d\n",
 845                       retcode, errno));
 846         if(retcode < 0) {
 847             perror("create_os_thread");
 848         }
 849         r=0;
 850     }
 851
 852 #ifdef LOCK_CREATE_THREAD
 853     retcode = pthread_mutex_unlock(&create_thread_lock);
 854     gc_assert(retcode == 0);
 855     FSHOW_SIGNAL((stderr,"/create_os_thread: released lock\n"));
 856 #endif
 857     thread_sigmask(SIG_SETMASK,&oldset,0);
 858     return r;
 859 }
 860
 861 os_thread_t create_thread(lispobj initial_function) {
 862     struct thread *th, *thread = arch_os_get_current_thread();
 863     os_thread_t kid_tid = 0;
 864
 865     /* Must defend against async unwinds. */
 866     if (SymbolValue(INTERRUPTS_ENABLED, thread) != NIL)
 867         lose("create_thread is not safe when interrupts are enabled.\n");
 868
 869     /* Assuming that a fresh thread struct has no lisp objects in it,
 870      * linking it to all_threads can be left to the thread itself
 871      * without fear of gc lossage. initial_function violates this
 872      * assumption and must stay pinned until the child starts up. */
 873     th = create_thread_struct(initial_function);
 874     if (th && !create_os_thread(th,&kid_tid)) {
 875         free_thread_struct(th);
 876         kid_tid = 0;
 877     }
 878     return kid_tid;
 879 }
 880
 881 /* stopping the world is a two-stage process.  From this thread we signal
 882  * all the others with SIG_STOP_FOR_GC.  The handler for this signal does
 883  * the usual pseudo-atomic checks (we don't want to stop a thread while
 884  * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC.
 885  */
 886 /*
 887  * (With SB-SAFEPOINT, see the definitions in safepoint.c instead.)
 888  */
 889 #ifndef LISP_FEATURE_SB_SAFEPOINT
 890
 891 /* To avoid deadlocks when gc stops the world all clients of each
 892  * mutex must enable or disable SIG_STOP_FOR_GC for the duration of
 893  * holding the lock, but they must agree on which. */
 894 void gc_stop_the_world()
 895 {
 896     struct thread *p,*th=arch_os_get_current_thread();
 897     int status, lock_ret;
 898 #ifdef LOCK_CREATE_THREAD
 899     /* KLUDGE: Stopping the thread during pthread_create() causes deadlock
 900      * on FreeBSD. */
 901     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:waiting on create_thread_lock\n"));
 902     lock_ret = pthread_mutex_lock(&create_thread_lock);
 903     gc_assert(lock_ret == 0);
 904     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:got create_thread_lock\n"));
 905 #endif
 906     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:waiting on lock\n"));
 907     /* keep threads from starting while the world is stopped. */
 908     lock_ret = pthread_mutex_lock(&all_threads_lock);      \
 909     gc_assert(lock_ret == 0);
 910
 911     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:got lock\n"));
 912     /* stop all other threads by sending them SIG_STOP_FOR_GC */
 913     for(p=all_threads; p; p=p->next) {
 914         gc_assert(p->os_thread != 0);
 915         FSHOW_SIGNAL((stderr,"/gc_stop_the_world: thread=%lu, state=%x\n",
 916                       p->os_thread, thread_state(p)));
 917         if((p!=th) && ((thread_state(p)==STATE_RUNNING))) {
 918             FSHOW_SIGNAL((stderr,"/gc_stop_the_world: suspending thread %lu\n",
 919                           p->os_thread));
 920             /* We already hold all_thread_lock, P can become DEAD but
 921              * cannot exit, ergo it's safe to use pthread_kill. */
 922             status=pthread_kill(p->os_thread,SIG_STOP_FOR_GC);
 923             if (status==ESRCH) {
 924                 /* This thread has exited. */
 925                 gc_assert(thread_state(p)==STATE_DEAD);
 926             } else if (status) {
 927                 lose("cannot send suspend thread=%lu: %d, %s\n",
 928                      p->os_thread,status,strerror(status));
 929             }
 930         }
 931     }
 932     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:signals sent\n"));
 933     for(p=all_threads;p;p=p->next) {
 934         if (p!=th) {
 935             FSHOW_SIGNAL
 936                 ((stderr,
 937                   "/gc_stop_the_world: waiting for thread=%lu: state=%x\n",
 938                   p->os_thread, thread_state(p)));
 939             wait_for_thread_state_change(p, STATE_RUNNING);
 940             if (p->state == STATE_RUNNING)
 941                 lose("/gc_stop_the_world: unexpected state");
 942         }
 943     }
 944     FSHOW_SIGNAL((stderr,"/gc_stop_the_world:end\n"));
 945 }
 946
 947 void gc_start_the_world()
 948 {
 949     struct thread *p,*th=arch_os_get_current_thread();
 950     int lock_ret;
 951     /* if a resumed thread creates a new thread before we're done with
 952      * this loop, the new thread will get consed on the front of
 953      * all_threads, but it won't have been stopped so won't need
 954      * restarting */
 955     FSHOW_SIGNAL((stderr,"/gc_start_the_world:begin\n"));
 956     for(p=all_threads;p;p=p->next) {
 957         gc_assert(p->os_thread!=0);
 958         if (p!=th) {
 959             lispobj state = thread_state(p);
 960             if (state != STATE_DEAD) {
 961                 if(state != STATE_STOPPED) {
 962                     lose("gc_start_the_world: wrong thread state is %d\n",
 963                          fixnum_value(state));
 964                 }
 965                 FSHOW_SIGNAL((stderr, "/gc_start_the_world: resuming %lu\n",
 966                               p->os_thread));
 967                 set_thread_state(p, STATE_RUNNING);
 968             }
 969         }
 970     }
 971
 972     lock_ret = pthread_mutex_unlock(&all_threads_lock);
 973     gc_assert(lock_ret == 0);
 974 #ifdef LOCK_CREATE_THREAD
 975     lock_ret = pthread_mutex_unlock(&create_thread_lock);
 976     gc_assert(lock_ret == 0);
 977 #endif
 978
 979     FSHOW_SIGNAL((stderr,"/gc_start_the_world:end\n"));
 980 }
 981
 982 #endif /* !LISP_FEATURE_SB_SAFEPOINT */
 983 #endif /* !LISP_FEATURE_SB_THREAD */
 984
 985 int
 986 thread_yield()
 987 {
 988 #ifdef LISP_FEATURE_SB_THREAD
 989     return sched_yield();
 990 #else
 991     return 0;
 992 #endif
 993 }
 994
 995 int
 996 wake_thread(os_thread_t os_thread)
 997 {
 998 #if defined(LISP_FEATURE_WIN32)
 999     return kill_safely(os_thread, 1);
1000 #elif !defined(LISP_FEATURE_SB_THRUPTION)
1001     return kill_safely(os_thread, SIGPIPE);
1002 #else
1003     return wake_thread_posix(os_thread);
1004 #endif
1005 }
1006
1007 /* If the thread id given does not belong to a running thread (it has
1008  * exited or never even existed) pthread_kill _may_ fail with ESRCH,
1009  * but it is also allowed to just segfault, see
1010  * <http://udrepper.livejournal.com/16844.html>.
1011  *
1012  * Relying on thread ids can easily backfire since ids are recycled
1013  * (NPTL recycles them extremely fast) so a signal can be sent to
1014  * another process if the one it was sent to exited.
1015  *
1016  * For these reasons, we must make sure that the thread is still alive
1017  * when the pthread_kill is called and return if the thread is
1018  * exiting.
1019  *
1020  * Note (DFL, 2011-06-22): At the time of writing, this function is only
1021  * used for INTERRUPT-THREAD, hence the wake_thread special-case for
1022  * Windows is OK. */
1023 int
1024 kill_safely(os_thread_t os_thread, int signal)
1025 {
1026     FSHOW_SIGNAL((stderr,"/kill_safely: %lu, %d\n", os_thread, signal));
1027     {
1028 #ifdef LISP_FEATURE_SB_THREAD
1029         sigset_t oldset;
1030         struct thread *thread;
1031         /* Frequent special case: resignalling to self.  The idea is
1032          * that leave_region safepoint will acknowledge the signal, so
1033          * there is no need to take locks, roll thread to safepoint
1034          * etc. */
1035         /* Kludge (on safepoint builds): At the moment, this isn't just
1036          * an optimization; rather it masks the fact that
1037          * gc_stop_the_world() grabs the all_threads mutex without
1038          * releasing it, and since we're not using recursive pthread
1039          * mutexes, the pthread_mutex_lock() around the all_threads loop
1040          * would go wrong.  Why are we running interruptions while
1041          * stopping the world though?  Test case is (:ASYNC-UNWIND
1042          * :SPECIALS), especially with s/10/100/ in both loops. */
1043         if (os_thread == pthread_self()) {
1044             pthread_kill(os_thread, signal);
1045 #ifdef LISP_FEATURE_WIN32
1046             check_pending_thruptions(NULL);
1047 #endif
1048             return 0;
1049         }
1050
1051         /* pthread_kill is not async signal safe and we don't want to be
1052          * interrupted while holding the lock. */
1053         block_deferrable_signals(0, &oldset);
1054         pthread_mutex_lock(&all_threads_lock);
1055         for (thread = all_threads; thread; thread = thread->next) {
1056             if (thread->os_thread == os_thread) {
1057                 int status = pthread_kill(os_thread, signal);
1058                 if (status)
1059                     lose("kill_safely: pthread_kill failed with %d\n", status);
1060 #if defined(LISP_FEATURE_WIN32) && defined(LISP_FEATURE_SB_THRUPTION)
1061                 wake_thread_win32(thread);
1062 #endif
1063                 break;
1064             }
1065         }
1066         pthread_mutex_unlock(&all_threads_lock);
1067         thread_sigmask(SIG_SETMASK,&oldset,0);
1068         if (thread)
1069             return 0;
1070         else
1071             return -1;
1072 #elif defined(LISP_FEATURE_WIN32)
1073         return 0;
1074 #else
1075         int status;
1076         if (os_thread != 0)
1077             lose("kill_safely: who do you want to kill? %d?\n", os_thread);
1078         /* Dubious (as in don't know why it works) workaround for the
1079          * signal sometimes not being generated on darwin. */
1080 #ifdef LISP_FEATURE_DARWIN
1081         {
1082             sigset_t oldset;
1083             sigprocmask(SIG_BLOCK, &deferrable_sigset, &oldset);
1084             status = raise(signal);
1085             sigprocmask(SIG_SETMASK,&oldset,0);
1086         }
1087 #else
1088         status = raise(signal);
1089 #endif
1090         if (status == 0) {
1091             return 0;
1092         } else {
1093             lose("cannot raise signal %d, %d %s\n",
1094                  signal, status, strerror(errno));
1095         }
1096 #endif
1097     }
1098 }