src/threads/native/threads.c

   1 #include "global.h"
   2
   3 #if defined(NATIVE_THREADS)
   4
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <assert.h>
   8 #include <sys/types.h>
   9 #include <unistd.h>
  10 #include <signal.h>
  11 #include <sys/time.h>
  12 #include <time.h>
  13 #include <errno.h>
  14
  15 #include "config.h"
  16 #include "thread.h"
  17 #include "codegen.h"
  18 #include "locks.h"
  19 #include "tables.h"
  20 #include "native.h"
  21 #include "loader.h"
  22 #include "builtin.h"
  23 #include "asmpart.h"
  24 #include "exceptions.h"
  25 #include "toolbox/logging.h"
  26 #include "toolbox/memory.h"
  27 #include "toolbox/avl.h"
  28 #include "mm/boehm.h"
  29
  30 #include "nat/java_lang_Object.h"
  31 #include "nat/java_lang_Throwable.h"
  32 #include "nat/java_lang_Thread.h"
  33 #include "nat/java_lang_ThreadGroup.h"
  34 #include "nat/java_lang_VMThread.h"
  35
  36 #include <pthread.h>
  37 #include <semaphore.h>
  38
  39 #if !defined(__DARWIN__)
  40 #if defined(__LINUX__)
  41 #define GC_LINUX_THREADS
  42 #elif defined(__MIPS__)
  43 #define GC_IRIX_THREADS
  44 #endif
  45 #include "../mm/boehm-gc/include/gc.h"
  46 #endif
  47
  48 #ifdef MUTEXSIM
  49
  50 /* We need this for older MacOSX (10.1.x) */
  51
  52 typedef struct {
  53         pthread_mutex_t mutex;
  54         pthread_t owner;
  55         int count;
  56 } pthread_mutex_rec_t;
  57
  58 static void pthread_mutex_init_rec(pthread_mutex_rec_t *m)
  59 {
  60         pthread_mutex_init(&m->mutex, NULL);
  61         m->count = 0;
  62 }
  63
  64 static void pthread_mutex_destroy_rec(pthread_mutex_rec_t *m)
  65 {
  66         pthread_mutex_destroy(&m->mutex);
  67 }
  68
  69 static void pthread_mutex_lock_rec(pthread_mutex_rec_t *m)
  70 {
  71         for (;;)
  72                 if (!m->count)
  73                 {
  74                         pthread_mutex_lock(&m->mutex);
  75                         m->owner = pthread_self();
  76                         m->count++;
  77                         break;
  78                 } else {
  79                         if (m->owner != pthread_self())
  80                                 pthread_mutex_lock(&m->mutex);
  81                         else
  82                         {
  83                                 m->count++;
  84                                 break;
  85                         }
  86                 }
  87 }
  88
  89 static void pthread_mutex_unlock_rec(pthread_mutex_rec_t *m)
  90 {
  91         if (!--m->count)
  92                 pthread_mutex_unlock(&m->mutex);
  93 }
  94
  95 #else /* MUTEXSIM */
  96
  97 #define pthread_mutex_lock_rec pthread_mutex_lock
  98 #define pthread_mutex_unlock_rec pthread_mutex_unlock
  99 #define pthread_mutex_rec_t pthread_mutex_t
 100
 101 #endif /* MUTEXSIM */
 102
 103 static void setPriority(pthread_t tid, int priority)
 104 {
 105         struct sched_param schedp;
 106         int policy;
 107
 108         pthread_getschedparam(tid, &policy, &schedp);
 109         schedp.sched_priority = priority;
 110         pthread_setschedparam(tid, policy, &schedp);
 111 }
 112
 113 #include "machine-instr.h"
 114
 115 static struct avl_table *criticaltree;
 116 static threadobject *mainthreadobj;
 117
 118 #ifndef HAVE___THREAD
 119 pthread_key_t tkey_threadinfo;
 120 #else
 121 __thread threadobject *threadobj;
 122 #endif
 123
 124 static pthread_mutex_rec_t compiler_mutex;
 125 static pthread_mutex_rec_t tablelock;
 126
 127 void compiler_lock()
 128 {
 129         pthread_mutex_lock_rec(&compiler_mutex);
 130 }
 131
 132 void compiler_unlock()
 133 {
 134         pthread_mutex_unlock_rec(&compiler_mutex);
 135 }
 136
 137 void tables_lock()
 138 {
 139     pthread_mutex_lock_rec(&tablelock);
 140 }
 141
 142 void tables_unlock()
 143 {
 144     pthread_mutex_unlock_rec(&tablelock);
 145 }
 146
 147 static int criticalcompare(const void *pa, const void *pb, void *param)
 148 {
 149         const threadcritnode *na = pa;
 150         const threadcritnode *nb = pb;
 151
 152         if (na->mcodebegin < nb->mcodebegin)
 153                 return -1;
 154         if (na->mcodebegin > nb->mcodebegin)
 155                 return 1;
 156         return 0;
 157 }
 158
 159 static const threadcritnode *findcritical(u1 *mcodeptr)
 160 {
 161     struct avl_node *n = criticaltree->avl_root;
 162     const threadcritnode *m = NULL;
 163     if (!n)
 164         return NULL;
 165     for (;;)
 166     {
 167         const threadcritnode *d = n->avl_data;
 168         if (mcodeptr == d->mcodebegin)
 169             return d;
 170         if (mcodeptr < d->mcodebegin) {
 171             if (n->avl_link[0])
 172                 n = n->avl_link[0];
 173             else
 174                 return m;
 175         } else {
 176             if (n->avl_link[1]) {
 177                 m = n->avl_data;
 178                 n = n->avl_link[1];
 179             } else
 180                 return n->avl_data;
 181         }
 182     }
 183 }
 184
 185 void thread_registercritical(threadcritnode *n)
 186 {
 187         avl_insert(criticaltree, n);
 188 }
 189
 190 u1 *thread_checkcritical(u1 *mcodeptr)
 191 {
 192         const threadcritnode *n = findcritical(mcodeptr);
 193         return (n && mcodeptr < n->mcodeend && mcodeptr > n->mcodebegin) ? n->mcoderestart : NULL;
 194 }
 195
 196 static void thread_addstaticcritical()
 197 {
 198         threadcritnode *n = &asm_criticalsections;
 199
 200         while (n->mcodebegin)
 201                 thread_registercritical(n++);
 202 }
 203
 204 static pthread_mutex_t threadlistlock;
 205
 206 static pthread_mutex_t stopworldlock;
 207 volatile int stopworldwhere;
 208
 209 static sem_t suspend_ack;
 210 #if defined(__MIPS__)
 211 static pthread_mutex_t suspend_ack_lock = PTHREAD_MUTEX_INITIALIZER;
 212 static pthread_cond_t suspend_cond = PTHREAD_COND_INITIALIZER;
 213 #endif
 214
 215 /*
 216  * where - 1 from within GC
 217            2 class numbering
 218  */
 219 void lock_stopworld(int where)
 220 {
 221         pthread_mutex_lock(&stopworldlock);
 222         stopworldwhere = where;
 223 }
 224
 225 void unlock_stopworld()
 226 {
 227         stopworldwhere = 0;
 228         pthread_mutex_unlock(&stopworldlock);
 229 }
 230
 231 #if !defined(__DARWIN__)
 232 /* Caller must hold threadlistlock */
 233 static int cast_sendsignals(int sig, int count)
 234 {
 235         /* Count threads */
 236         threadobject *tobj = mainthreadobj;
 237         nativethread *infoself = THREADINFO;
 238
 239         if (count == 0)
 240                 do {
 241                         count++;
 242                         tobj = tobj->info.next;
 243                 } while (tobj != mainthreadobj);
 244
 245         do {
 246                 nativethread *info = &tobj->info;
 247                 if (info != infoself)
 248                         pthread_kill(info->tid, sig);
 249                 tobj = tobj->info.next;
 250         } while (tobj != mainthreadobj);
 251
 252         return count-1;
 253 }
 254
 255 #else
 256
 257 static void cast_darwinstop()
 258 {
 259         threadobject *tobj = mainthreadobj;
 260         nativethread *infoself = THREADINFO;
 261
 262         do {
 263                 nativethread *info = &tobj->info;
 264                 if (info != infoself)
 265                 {
 266                         thread_state_flavor_t flavor = PPC_THREAD_STATE;
 267                         mach_msg_type_number_t thread_state_count = PPC_THREAD_STATE_COUNT;
 268                         ppc_thread_state_t thread_state;
 269                         mach_port_t thread = info->mach_thread;
 270                         kern_return_t r;
 271
 272                         r = thread_suspend(thread);
 273                         if (r != KERN_SUCCESS)
 274                                 panic("thread_suspend failed");
 275
 276                         r = thread_get_state(thread, flavor,
 277                                 (natural_t*)&thread_state, &thread_state_count);
 278                         if (r != KERN_SUCCESS)
 279                                 panic("thread_get_state failed");
 280
 281                         thread_restartcriticalsection(&thread_state);
 282
 283                         r = thread_set_state(thread, flavor,
 284                                 (natural_t*)&thread_state, thread_state_count);
 285                         if (r != KERN_SUCCESS)
 286                                 panic("thread_set_state failed");
 287                 }
 288                 tobj = tobj->info.next;
 289         } while (tobj != mainthreadobj);
 290 }
 291
 292 static void cast_darwinresume()
 293 {
 294         threadobject *tobj = mainthreadobj;
 295         nativethread *infoself = THREADINFO;
 296
 297         do {
 298                 nativethread *info = &tobj->info;
 299                 if (info != infoself)
 300                 {
 301                         r = thread_resume(thread);
 302                         if (r != KERN_SUCCESS)
 303                                 panic("thread_resume failed");
 304                 }
 305                 tobj = tobj->info.next;
 306         } while (tobj != mainthreadobj);
 307 }
 308
 309 #endif
 310
 311 #if defined(__MIPS__)
 312 static void cast_irixresume()
 313 {
 314         pthread_mutex_lock(&suspend_ack_lock);
 315         pthread_cond_broadcast(&suspend_cond);
 316         pthread_mutex_unlock(&suspend_ack_lock);
 317 }
 318 #endif
 319
 320 void cast_stopworld()
 321 {
 322         int count, i;
 323         lock_stopworld(2);
 324         pthread_mutex_lock(&threadlistlock);
 325 #if defined(__DARWIN__)
 326         cast_darwinstop();
 327 #else
 328         count = cast_sendsignals(GC_signum1(), 0);
 329         for (i=0; i<count; i++)
 330                 sem_wait(&suspend_ack);
 331 #endif
 332         pthread_mutex_unlock(&threadlistlock);
 333 }
 334
 335 void cast_startworld()
 336 {
 337         pthread_mutex_lock(&threadlistlock);
 338 #if defined(__DARWIN__)
 339         cast_darwinresume();
 340 #elif defined(__MIPS__)
 341         cast_irixresume();
 342 #else
 343         cast_sendsignals(GC_signum2(), -1);
 344 #endif
 345         pthread_mutex_unlock(&threadlistlock);
 346         unlock_stopworld();
 347 }
 348
 349 #if !defined(__DARWIN__)
 350 static void sigsuspend_handler(ucontext_t *ctx)
 351 {
 352         int sig;
 353         sigset_t sigs;
 354
 355         thread_restartcriticalsection(ctx);
 356
 357         /* Do as Boehm does. On IRIX a condition variable is used for wake-up
 358            (not POSIX async-safe). */
 359 #if defined(__MIPS__)
 360         pthread_mutex_lock(&suspend_ack_lock);
 361         sem_post(&suspend_ack);
 362         pthread_cond_wait(&suspend_cond, &suspend_ack_lock);
 363         pthread_mutex_unlock(&suspend_ack_lock);
 364 #else
 365         sem_post(&suspend_ack);
 366
 367         sig = GC_signum2();
 368         sigfillset(&sigs);
 369         sigdelset(&sigs, sig);
 370         sigsuspend(&sigs);
 371 #endif
 372 }
 373
 374 int cacao_suspendhandler(ucontext_t *ctx)
 375 {
 376         if (stopworldwhere != 2)
 377                 return 0;
 378
 379         sigsuspend_handler(ctx);
 380         return 1;
 381 }
 382 #endif
 383
 384 static void setthreadobject(threadobject *thread)
 385 {
 386 #if !defined(HAVE___THREAD)
 387         pthread_setspecific(tkey_threadinfo, thread);
 388 #else
 389         threadobj = thread;
 390 #endif
 391 }
 392
 393 static monitorLockRecord *dummyLR;
 394
 395 static void initPools();
 396
 397 /*
 398  * Initialize threads.
 399  */
 400 void
 401 initThreadsEarly()
 402 {
 403 #ifndef MUTEXSIM
 404         pthread_mutexattr_t mutexattr;
 405         pthread_mutexattr_init(&mutexattr);
 406         pthread_mutexattr_settype(&mutexattr, PTHREAD_MUTEX_RECURSIVE);
 407         pthread_mutex_init(&compiler_mutex, &mutexattr);
 408         pthread_mutex_init(&tablelock, &mutexattr);
 409         pthread_mutexattr_destroy(&mutexattr);
 410 #else
 411         pthread_mutex_init_rec(&compiler_mutex);
 412         pthread_mutex_init_rec(&tablelock);
 413 #endif
 414
 415         pthread_mutex_init(&threadlistlock, NULL);
 416         pthread_mutex_init(&stopworldlock, NULL);
 417
 418         /* Allocate something so the garbage collector's signal handlers are  */
 419         /* installed. */
 420         heap_allocate(1, false, NULL);
 421
 422         mainthreadobj = NEW(threadobject);
 423         memset(mainthreadobj, 0, sizeof(threadobject));
 424         mainthreadobj->info.tid = pthread_self();
 425 #if !defined(HAVE___THREAD)
 426         pthread_key_create(&tkey_threadinfo, NULL);
 427 #endif
 428         setthreadobject(mainthreadobj);
 429         initPools();
 430
 431     criticaltree = avl_create(criticalcompare, NULL, NULL);
 432         thread_addstaticcritical();
 433         sem_init(&suspend_ack, 0, 0);
 434
 435         /* Every newly created object's monitorPtr points here so we save a check
 436          * against NULL */
 437         dummyLR = mem_alloc(sizeof(monitorLockRecord));
 438         dummyLR->o = NULL;
 439         dummyLR->ownerThread = NULL;
 440         dummyLR->waiting = false;
 441 }
 442
 443 static pthread_attr_t threadattr;
 444
 445 static void freeLockRecordPools(lockRecordPool *);
 446
 447 void
 448 initThreads(u1 *stackbottom)
 449 {
 450         classinfo *threadclass;
 451         classinfo *threadgroupclass;
 452         java_lang_String *threadname;
 453         java_lang_Thread *mainthread;
 454         java_lang_ThreadGroup *threadgroup;
 455         threadobject *tempthread = mainthreadobj;
 456         methodinfo *method;
 457
 458         threadclass = class_new(utf_new_char("java/lang/VMThread"));
 459         class_load(threadclass);
 460         class_link(threadclass);
 461
 462         if (!threadclass)
 463                 throw_exception_exit();
 464
 465         freeLockRecordPools(mainthreadobj->ee.lrpool);
 466         /* This is kinda tricky, we grow the java.lang.Thread object so we can keep
 467          * the execution environment there. No Thread object must have been created
 468          * at an earlier time */
 469         threadclass->instancesize = sizeof(threadobject);
 470
 471         /* Create a VMThread */
 472         mainthreadobj = (threadobject *) builtin_new(threadclass);
 473
 474         if (!mainthreadobj)
 475                 throw_exception_exit();
 476
 477         FREE(tempthread, threadobject);
 478         initThread(&mainthreadobj->o);
 479
 480         setthreadobject(mainthreadobj);
 481
 482         initLocks();
 483         mainthreadobj->info.next = mainthreadobj;
 484         mainthreadobj->info.prev = mainthreadobj;
 485
 486         threadname = javastring_new(utf_new_char("main"));
 487
 488         /* Allocate and init ThreadGroup */
 489         threadgroupclass = class_new(utf_new_char("java/lang/ThreadGroup"));
 490         threadgroup =
 491                 (java_lang_ThreadGroup *) native_new_and_init(threadgroupclass);
 492
 493         if (!threadgroup)
 494                 throw_exception_exit();
 495
 496         /* Create a Thread */
 497         threadclass = class_new(utf_new_char("java/lang/Thread"));
 498         mainthread = (java_lang_Thread*) builtin_new(threadclass);
 499         mainthreadobj->o.thread = mainthread;
 500
 501         if (!mainthread)
 502                 throw_exception_exit();
 503
 504         /* Call Thread constructor */
 505         method = class_resolveclassmethod(threadclass,
 506                                                                           utf_new_char("<init>"),
 507                                                                           utf_new_char("(Ljava/lang/VMThread;Ljava/lang/String;IZ)V"),
 508                                                                           threadclass,
 509                                                                           true);
 510
 511         if (!method)
 512                 throw_exception_exit();
 513
 514         asm_calljavafunction(method, mainthread, mainthreadobj, threadname, (void*) 5);
 515         if (*exceptionptr)
 516                 throw_exception_exit();
 517
 518         mainthread->group = threadgroup;
 519         /* XXX This is a hack because the fourth argument was omitted */
 520         mainthread->daemon = false;
 521
 522         /* Add mainthread to ThreadGroup */
 523         method = class_resolveclassmethod(threadgroupclass,
 524                                                                           utf_new_char("addThread"),
 525                                                                           utf_new_char("(Ljava/lang/Thread;)V"),
 526                                                                           threadgroupclass,
 527                                                                           true);
 528
 529         if (!method)
 530                 throw_exception_exit();
 531
 532         asm_calljavafunction(method, threadgroup, mainthread, NULL, NULL);
 533         if (*exceptionptr)
 534                 throw_exception_exit();
 535
 536         /* TODO InheritableThreadLocal */
 537
 538         setPriority(pthread_self(), 5);
 539
 540         pthread_attr_init(&threadattr);
 541         pthread_attr_setdetachstate(&threadattr, PTHREAD_CREATE_DETACHED);
 542 }
 543
 544 void initThread(java_lang_VMThread *t)
 545 {
 546         threadobject *thread = (threadobject*) t;
 547         nativethread *info = &thread->info;
 548         info->tid = pthread_self();
 549         pthread_mutex_init(&info->joinMutex, NULL);
 550         pthread_cond_init(&info->joinCond, NULL);
 551
 552         thread->interrupted = 0;
 553         thread->waiting = NULL;
 554 }
 555
 556 static void initThreadLocks(threadobject *);
 557
 558 typedef struct {
 559         threadobject *thread;
 560         sem_t *psem;
 561 } startupinfo;
 562
 563 static void *threadstartup(void *t)
 564 {
 565         startupinfo *startup = t;
 566         threadobject *thread = startup->thread;
 567         sem_t *psem = startup->psem;
 568         nativethread *info = &thread->info;
 569         threadobject *tnext;
 570         methodinfo *method;
 571
 572         t = NULL;
 573 #if defined(__DARWIN__)
 574         info->mach_thread = mach_thread_self();
 575 #endif
 576         setthreadobject(thread);
 577
 578         pthread_mutex_lock(&threadlistlock);
 579         info->prev = mainthreadobj;
 580         info->next = tnext = mainthreadobj->info.next;
 581         mainthreadobj->info.next = thread;
 582         tnext->info.prev = thread;
 583         pthread_mutex_unlock(&threadlistlock);
 584
 585         initThreadLocks(thread);
 586
 587         startup = NULL;
 588         sem_post(psem);
 589
 590         setPriority(info->tid, thread->o.thread->priority);
 591
 592         /* Find the run()V method and call it */
 593         method = class_resolveclassmethod(thread->o.header.vftbl->class,
 594                                                                           utf_new_char("run"),
 595                                                                           utf_new_char("()V"),
 596                                                                           thread->o.header.vftbl->class,
 597                                                                           true);
 598
 599         /* if method != NULL, we had not exception */
 600         if (method) {
 601                 asm_calljavafunction(method, thread, NULL, NULL, NULL);
 602
 603         } else {
 604                 throw_exception();
 605         }
 606
 607         /* Allow lock record pools to be used by other threads. They cannot be
 608          * deleted so we'd better not waste them. */
 609         freeLockRecordPools(thread->ee.lrpool);
 610
 611         pthread_mutex_lock(&threadlistlock);
 612         info->next->info.prev = info->prev;
 613         info->prev->info.next = info->next;
 614         pthread_mutex_unlock(&threadlistlock);
 615
 616         pthread_mutex_lock(&info->joinMutex);
 617         info->tid = 0;
 618         pthread_mutex_unlock(&info->joinMutex);
 619         pthread_cond_broadcast(&info->joinCond);
 620
 621         return NULL;
 622 }
 623
 624 void startThread(thread *t)
 625 {
 626         nativethread *info = &((threadobject*) t->vmThread)->info;
 627         sem_t sem;
 628         startupinfo startup;
 629
 630         startup.thread = (threadobject*) t->vmThread;
 631         startup.psem = &sem;
 632
 633         sem_init(&sem, 0, 0);
 634
 635         if (pthread_create(&info->tid, &threadattr, threadstartup, &startup))
 636                 panic("pthread_create failed");
 637
 638         /* Wait here until the thread has entered itself into the thread list */
 639         sem_wait(&sem);
 640         sem_destroy(&sem);
 641 }
 642
 643 /* At the end of the program, we wait for all running non-daemon threads to die
 644  */
 645
 646 static threadobject *findNonDaemon(threadobject *thread)
 647 {
 648         while (thread != mainthreadobj) {
 649                 if (!thread->o.thread->daemon)
 650                         return thread;
 651                 thread = thread->info.prev;
 652         }
 653
 654         return NULL;
 655 }
 656
 657 void joinAllThreads()
 658 {
 659         threadobject *thread;
 660         pthread_mutex_lock(&threadlistlock);
 661         while ((thread = findNonDaemon(mainthreadobj->info.prev)) != NULL) {
 662                 nativethread *info = &thread->info;
 663                 pthread_mutex_lock(&info->joinMutex);
 664                 pthread_mutex_unlock(&threadlistlock);
 665                 if (info->tid)
 666                         pthread_cond_wait(&info->joinCond, &info->joinMutex);
 667                 pthread_mutex_unlock(&info->joinMutex);
 668                 pthread_mutex_lock(&threadlistlock);
 669         }
 670         pthread_mutex_unlock(&threadlistlock);
 671 }
 672
 673 static void initLockRecord(monitorLockRecord *r, threadobject *t)
 674 {
 675         r->lockCount = 1;
 676         r->ownerThread = t;
 677         r->queuers = 0;
 678         r->o = NULL;
 679         r->waiter = NULL;
 680         r->incharge = NULL;
 681         r->waiting = false;
 682         sem_init(&r->queueSem, 0, 0);
 683         pthread_mutex_init(&r->resolveLock, NULL);
 684         pthread_cond_init(&r->resolveWait, NULL);
 685         pthread_mutex_init(&r->waitLock, NULL);
 686         pthread_cond_init(&r->waitCond, NULL);
 687 }
 688
 689 /* No lock record must ever be destroyed because there may still be references
 690  * to it.
 691
 692 static void destroyLockRecord(monitorLockRecord *r)
 693 {
 694         sem_destroy(&r->queueSem);
 695         pthread_mutex_destroy(&r->resolveLock);
 696         pthread_cond_destroy(&r->resolveWait);
 697         pthread_mutex_destroy(&r->waitLock);
 698         pthread_cond_destroy(&r->waitCond);
 699 }
 700 */
 701
 702 void initLocks()
 703 {
 704         initThreadLocks(mainthreadobj);
 705 }
 706
 707 static void initThreadLocks(threadobject *thread)
 708 {
 709         thread->ee.firstLR = NULL;
 710         thread->ee.lrpool = NULL;
 711         thread->ee.numlr = 0;
 712 }
 713
 714 static lockRecordPool *allocNewLockRecordPool(threadobject *thread, int size)
 715 {
 716         lockRecordPool *p = mem_alloc(sizeof(lockRecordPoolHeader) + sizeof(monitorLockRecord) * size);
 717         int i;
 718
 719         p->header.size = size;
 720         for (i=0; i<size; i++) {
 721                 initLockRecord(&p->lr[i], thread);
 722                 p->lr[i].nextFree = &p->lr[i+1];
 723         }
 724         p->lr[i-1].nextFree = NULL;
 725         return p;
 726 }
 727
 728 #define INITIALLOCKRECORDS 8
 729
 730 static pthread_mutex_t pool_lock;
 731 static lockRecordPool *global_pool;
 732
 733 static void initPools()
 734 {
 735         pthread_mutex_init(&pool_lock, NULL);
 736 }
 737
 738 static lockRecordPool *allocLockRecordPool(threadobject *t, int size)
 739 {
 740         pthread_mutex_lock(&pool_lock);
 741         if (global_pool) {
 742                 int i;
 743                 lockRecordPool *pool = global_pool;
 744                 global_pool = pool->header.next;
 745                 pthread_mutex_unlock(&pool_lock);
 746
 747                 for (i=0; i < pool->header.size; i++)
 748                         pool->lr[i].ownerThread = t;
 749
 750                 return pool;
 751         }
 752         pthread_mutex_unlock(&pool_lock);
 753
 754         return allocNewLockRecordPool(t, size);
 755 }
 756
 757 static void freeLockRecordPools(lockRecordPool *pool)
 758 {
 759         lockRecordPoolHeader *last;
 760         pthread_mutex_lock(&pool_lock);
 761         last = &pool->header;
 762         while (last->next)
 763                 last = &last->next->header;
 764         last->next = global_pool;
 765         global_pool = pool;
 766         pthread_mutex_unlock(&pool_lock);
 767 }
 768
 769 static monitorLockRecord *allocLockRecordSimple(threadobject *t)
 770 {
 771         monitorLockRecord *r = t->ee.firstLR;
 772
 773         if (!r) {
 774                 int poolsize = t->ee.numlr ? t->ee.numlr * 2 : INITIALLOCKRECORDS;
 775                 lockRecordPool *pool = allocLockRecordPool(t, poolsize);
 776                 pool->header.next = t->ee.lrpool;
 777                 t->ee.lrpool = pool;
 778                 r = &pool->lr[0];
 779                 t->ee.numlr += pool->header.size;
 780         }
 781
 782         t->ee.firstLR = r->nextFree;
 783         return r;
 784 }
 785
 786 static inline void recycleLockRecord(threadobject *t, monitorLockRecord *r)
 787 {
 788         r->nextFree = t->ee.firstLR;
 789         t->ee.firstLR = r;
 790 }
 791
 792 #if 0
 793 static monitorLockRecord *allocLockRecord(threadobject *t, monitorLockRecord *lr)
 794 {
 795         monitorLockRecord *r = allocLockRecordSimple(t);
 796         if (r == lr) {
 797                 monitorLockRecord *r2 = allocLockRecordSimple(t);
 798                 recycleLockRecord(t, r);
 799                 r = r2;
 800         }
 801         return r;
 802 }
 803 #endif
 804
 805 void initObjectLock(java_objectheader *o)
 806 {
 807         o->monitorPtr = dummyLR;
 808 }
 809
 810 static void queueOnLockRecord(monitorLockRecord *lr, java_objectheader *o)
 811 {
 812         atomic_add(&lr->queuers, 1);
 813         MEMORY_BARRIER_AFTER_ATOMIC();
 814         if (lr->o == o)
 815                 sem_wait(&lr->queueSem);
 816         atomic_add(&lr->queuers, -1);
 817 }
 818
 819 static void freeLockRecord(monitorLockRecord *lr)
 820 {
 821         int q;
 822         lr->o = NULL;
 823         MEMORY_BARRIER();
 824         q = lr->queuers;
 825         while (q--)
 826                 sem_post(&lr->queueSem);
 827 }
 828
 829 static inline void handleWaiter(monitorLockRecord *mlr, monitorLockRecord *lr)
 830 {
 831         if (lr->waiting)
 832                 mlr->waiter = lr;
 833 }
 834
 835 monitorLockRecord *monitorEnter(threadobject *t, java_objectheader *o)
 836 {
 837         for (;;) {
 838                 monitorLockRecord *lr = o->monitorPtr;
 839                 if (lr->o != o) {
 840                         monitorLockRecord *nlr, *mlr = allocLockRecordSimple(t);
 841                         mlr->o = o;
 842                         MEMORY_BARRIER_BEFORE_ATOMIC();
 843                         nlr = (void*) compare_and_swap((long*) &o->monitorPtr, (long) lr, (long) mlr);
 844                         if (nlr == lr) {
 845                                 if (mlr == lr || lr->o != o) {
 846                                         handleWaiter(mlr, lr);
 847                                         return mlr;
 848                                 } else {
 849                                         void *incharge;
 850                                         pthread_mutex_lock(&mlr->resolveLock);
 851                                         incharge = mlr->incharge;
 852                                         mlr->incharge = lr;
 853                                         pthread_mutex_unlock(&mlr->resolveLock);
 854                                         if (incharge)
 855                                                 pthread_cond_signal(&mlr->resolveWait);
 856                                 }
 857                                 while (lr->o == o)
 858                                         queueOnLockRecord(lr, o);
 859                                 mlr->incharge = NULL;
 860                                 handleWaiter(mlr, lr);
 861                                 return mlr;
 862                         }
 863                         freeLockRecord(mlr);
 864                         recycleLockRecord(t, mlr);
 865                         queueOnLockRecord(nlr, o);
 866                 } else {
 867                         if (lr->ownerThread == t) {
 868                                 lr->lockCount++;
 869                                 return lr;
 870                         }
 871                         queueOnLockRecord(lr, o);
 872                 }
 873         }
 874 }
 875
 876 static monitorLockRecord *grabLockRecordInCharge(monitorLockRecord *lr)
 877 {
 878         pthread_mutex_lock(&lr->resolveLock);
 879         if (!lr->incharge) {
 880                 lr->incharge = lr;
 881                 pthread_cond_wait(&lr->resolveWait, &lr->resolveLock);
 882         }
 883         pthread_mutex_unlock(&lr->resolveLock);
 884         return lr->incharge;
 885 }
 886
 887 static void wakeWaiters(monitorLockRecord *lr)
 888 {
 889         do {
 890                 int q = lr->queuers;
 891                 while (q--)
 892                         sem_post(&lr->queueSem);
 893                 lr = lr->waiter;
 894         } while (lr);
 895 }
 896
 897 #define GRAB_LR(lr,t) \
 898     if (lr->ownerThread != t) { \
 899                 lr = grabLockRecordInCharge(lr); \
 900                 assert(lr->ownerThread == t); \
 901         }
 902
 903 #define CHECK_MONITORSTATE(lr,mo,a) \
 904     if (lr->o != mo) { \
 905                 *exceptionptr = new_exception(string_java_lang_IllegalMonitorStateException); \
 906                 a; \
 907         }
 908
 909 bool monitorExit(threadobject *t, java_objectheader *o)
 910 {
 911         monitorLockRecord *lr = o->monitorPtr;
 912         GRAB_LR(lr, t);
 913         CHECK_MONITORSTATE(lr, o, return false);
 914         if (lr->lockCount > 1) {
 915                 lr->lockCount--;
 916                 return true;
 917         }
 918         if (lr->waiter) {
 919                 monitorLockRecord *wlr = lr->waiter;
 920                 if (o->monitorPtr != lr ||
 921                         (void*) compare_and_swap((long*) &o->monitorPtr, (long) lr, (long) wlr) != lr)
 922                 {
 923                         monitorLockRecord *nlr = o->monitorPtr;
 924                         nlr->waiter = wlr;
 925                         STORE_ORDER_BARRIER();
 926                 } else
 927                         wakeWaiters(wlr);
 928                 lr->waiter = NULL;
 929         }
 930         freeLockRecord(lr);
 931         recycleLockRecord(t, lr);
 932         return true;
 933 }
 934
 935 static void removeFromWaiters(monitorLockRecord *lr, monitorLockRecord *wlr)
 936 {
 937         do {
 938                 if (lr->waiter == wlr) {
 939                         lr->waiter = wlr->waiter;
 940                         break;
 941                 }
 942                 lr = lr->waiter;
 943         } while (lr);
 944 }
 945
 946 bool waitWithTimeout(threadobject *t, monitorLockRecord *lr, struct timespec *wakeupTime)
 947 {
 948         bool wasinterrupted;
 949
 950         pthread_mutex_lock(&lr->waitLock);
 951         t->waiting = lr;
 952         if (wakeupTime->tv_sec || wakeupTime->tv_nsec)
 953                 pthread_cond_timedwait(&lr->waitCond, &lr->waitLock, wakeupTime);
 954         else
 955                 pthread_cond_wait(&lr->waitCond, &lr->waitLock);
 956         wasinterrupted = t->waiting == NULL;
 957         t->waiting = NULL;
 958         pthread_mutex_unlock(&lr->waitLock);
 959         return wasinterrupted;
 960 }
 961
 962 static void calcAbsoluteTime(struct timespec *tm, s8 millis, s4 nanos)
 963 {
 964         if (millis || nanos) {
 965                 struct timeval tv;
 966                 long nsec;
 967                 gettimeofday(&tv, NULL);
 968                 tv.tv_sec += millis / 1000;
 969                 millis %= 1000;
 970                 nsec = tv.tv_usec * 1000 + (s4) millis * 1000000 + nanos;
 971                 tm->tv_sec = tv.tv_sec + nsec / 1000000000;
 972                 tm->tv_nsec = nsec % 1000000000;
 973         } else {
 974                 tm->tv_sec = 0;
 975                 tm->tv_nsec = 0;
 976         }
 977 }
 978
 979 void monitorWait(threadobject *t, java_objectheader *o, s8 millis, s4 nanos)
 980 {
 981         bool wasinterrupted;
 982         struct timespec wakeupTime;
 983         monitorLockRecord *mlr, *lr = o->monitorPtr;
 984         GRAB_LR(lr, t);
 985         CHECK_MONITORSTATE(lr, o, return);
 986
 987         calcAbsoluteTime(&wakeupTime, millis, nanos);
 988
 989         if (lr->waiter)
 990                 wakeWaiters(lr->waiter);
 991         lr->waiting = true;
 992         STORE_ORDER_BARRIER();
 993         freeLockRecord(lr);
 994         wasinterrupted = waitWithTimeout(t, lr, &wakeupTime);
 995         mlr = monitorEnter(t, o);
 996         removeFromWaiters(mlr, lr);
 997         mlr->lockCount = lr->lockCount;
 998         lr->lockCount = 1;
 999         lr->waiting = false;
1000         lr->waiter = NULL;
1001         recycleLockRecord(t, lr);
1002
1003         if (wasinterrupted)
1004                 *exceptionptr = new_exception(string_java_lang_InterruptedException);
1005 }
1006
1007 static void notifyOneOrAll(threadobject *t, java_objectheader *o, bool one)
1008 {
1009         monitorLockRecord *lr = o->monitorPtr;
1010         GRAB_LR(lr, t);
1011         CHECK_MONITORSTATE(lr, o, return);
1012         do {
1013                 monitorLockRecord *wlr = lr->waiter;
1014                 if (!wlr)
1015                         break;
1016                 pthread_cond_signal(&wlr->waitCond);
1017                 lr = wlr;
1018         } while (!one);
1019 }
1020
1021 void interruptThread(java_lang_VMThread *thread)
1022 {
1023         threadobject *t = (threadobject*) thread;
1024
1025         monitorLockRecord *lr = t->waiting;
1026         if (lr) {
1027                 pthread_mutex_lock(&lr->waitLock);
1028                 if (t->waiting == lr) {
1029                         t->waiting = NULL;
1030                         pthread_cond_signal(&lr->waitCond);
1031                 }
1032                 pthread_mutex_unlock(&lr->waitLock);
1033                 return;
1034         }
1035
1036         t->interrupted = 1;
1037 }
1038
1039 bool interruptedThread()
1040 {
1041         threadobject *t = (threadobject*) THREADOBJECT;
1042         long intr = t->interrupted;
1043         t->interrupted = 0;
1044         return intr;
1045 }
1046
1047 bool isInterruptedThread(java_lang_VMThread *thread)
1048 {
1049         threadobject *t = (threadobject*) thread;
1050         return t->interrupted;
1051 }
1052
1053 void sleepThread(s8 millis, s4 nanos)
1054 {
1055         bool wasinterrupted;
1056         threadobject *t = (threadobject*) THREADOBJECT;
1057         monitorLockRecord *lr;
1058         struct timespec wakeupTime;
1059         calcAbsoluteTime(&wakeupTime, millis, nanos);
1060
1061         lr = allocLockRecordSimple(t);
1062         wasinterrupted = waitWithTimeout(t, lr, &wakeupTime);
1063         recycleLockRecord(t, lr);
1064
1065         if (wasinterrupted)
1066                 *exceptionptr = new_exception(string_java_lang_InterruptedException);
1067 }
1068
1069 void yieldThread()
1070 {
1071         sched_yield();
1072 }
1073
1074 void setPriorityThread(thread *t, s4 priority)
1075 {
1076         nativethread *info = &((threadobject*) t->vmThread)->info;
1077         setPriority(info->tid, priority);
1078 }
1079
1080 void wait_cond_for_object(java_objectheader *o, s8 time, s4 nanos)
1081 {
1082         threadobject *t = (threadobject*) THREADOBJECT;
1083         monitorWait(t, o, time, nanos);
1084 }
1085
1086 void signal_cond_for_object(java_objectheader *o)
1087 {
1088         threadobject *t = (threadobject*) THREADOBJECT;
1089         notifyOneOrAll(t, o, true);
1090 }
1091
1092 void broadcast_cond_for_object(java_objectheader *o)
1093 {
1094         threadobject *t = (threadobject*) THREADOBJECT;
1095         notifyOneOrAll(t, o, false);
1096 }
1097
1098 #endif
1099
1100
1101 /*
1102  * These are local overrides for various environment variables in Emacs.
1103  * Please do not remove this and leave it at the end of the file, where
1104  * Emacs will automagically detect them.
1105  * ---------------------------------------------------------------------
1106  * Local variables:
1107  * mode: c
1108  * indent-tabs-mode: t
1109  * c-basic-offset: 4
1110  * tab-width: 4
1111  * End:
1112  */