brintos

brintos / llvm-project-archived public Read only

0
0
Text · 137.3 KiB · fd13003 Raw
4049 lines · cpp
1/*2 * kmp_lock.cpp -- lock-related functions3 */4 5//===----------------------------------------------------------------------===//6//7// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.8// See https://llvm.org/LICENSE.txt for license information.9// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception10//11//===----------------------------------------------------------------------===//12 13#include <stddef.h>14#include <atomic>15 16#include "kmp.h"17#include "kmp_i18n.h"18#include "kmp_io.h"19#include "kmp_itt.h"20#include "kmp_lock.h"21#include "kmp_wait_release.h"22#include "kmp_wrapper_getpid.h"23 24#if KMP_USE_FUTEX25#include <sys/syscall.h>26#include <unistd.h>27// We should really include <futex.h>, but that causes compatibility problems on28// different Linux* OS distributions that either require that you include (or29// break when you try to include) <pci/types.h>. Since all we need is the two30// macros below (which are part of the kernel ABI, so can't change) we just31// define the constants here and don't include <futex.h>32#ifndef FUTEX_WAIT33#define FUTEX_WAIT 034#endif35#ifndef FUTEX_WAKE36#define FUTEX_WAKE 137#endif38#endif39 40/* Implement spin locks for internal library use.             */41/* The algorithm implemented is Lamport's bakery lock [1974]. */42 43void __kmp_validate_locks(void) {44  int i;45  kmp_uint32 x, y;46 47  /* Check to make sure unsigned arithmetic does wraps properly */48  x = ~((kmp_uint32)0) - 2;49  y = x - 2;50 51  for (i = 0; i < 8; ++i, ++x, ++y) {52    kmp_uint32 z = (x - y);53    KMP_ASSERT(z == 2);54  }55 56  KMP_ASSERT(offsetof(kmp_base_queuing_lock, tail_id) % 8 == 0);57}58 59/* ------------------------------------------------------------------------ */60/* test and set locks */61 62// For the non-nested locks, we can only assume that the first 4 bytes were63// allocated, since gcc only allocates 4 bytes for omp_lock_t, and the Intel64// compiler only allocates a 4 byte pointer on IA-32 architecture.  On65// Windows* OS on Intel(R) 64, we can assume that all 8 bytes were allocated.66//67// gcc reserves >= 8 bytes for nested locks, so we can assume that the68// entire 8 bytes were allocated for nested locks on all 64-bit platforms.69 70static kmp_int32 __kmp_get_tas_lock_owner(kmp_tas_lock_t *lck) {71  return KMP_LOCK_STRIP(KMP_ATOMIC_LD_RLX(&lck->lk.poll)) - 1;72}73 74static inline bool __kmp_is_tas_lock_nestable(kmp_tas_lock_t *lck) {75  return lck->lk.depth_locked != -1;76}77 78__forceinline static int79__kmp_acquire_tas_lock_timed_template(kmp_tas_lock_t *lck, kmp_int32 gtid) {80  KMP_MB();81 82#ifdef USE_LOCK_PROFILE83  kmp_uint32 curr = KMP_LOCK_STRIP(lck->lk.poll);84  if ((curr != 0) && (curr != gtid + 1))85    __kmp_printf("LOCK CONTENTION: %p\n", lck);86/* else __kmp_printf( "." );*/87#endif /* USE_LOCK_PROFILE */88 89  kmp_int32 tas_free = KMP_LOCK_FREE(tas);90  kmp_int32 tas_busy = KMP_LOCK_BUSY(gtid + 1, tas);91 92  if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == tas_free &&93      __kmp_atomic_compare_store_acq(&lck->lk.poll, tas_free, tas_busy)) {94    KMP_FSYNC_ACQUIRED(lck);95    return KMP_LOCK_ACQUIRED_FIRST;96  }97 98  kmp_uint32 spins;99  kmp_uint64 time;100  KMP_FSYNC_PREPARE(lck);101  KMP_INIT_YIELD(spins);102  KMP_INIT_BACKOFF(time);103  kmp_backoff_t backoff = __kmp_spin_backoff_params;104  do {105#if !KMP_HAVE_UMWAIT106    __kmp_spin_backoff(&backoff);107#else108    if (!__kmp_tpause_enabled)109      __kmp_spin_backoff(&backoff);110#endif111    KMP_YIELD_OVERSUB_ELSE_SPIN(spins, time);112  } while (KMP_ATOMIC_LD_RLX(&lck->lk.poll) != tas_free ||113           !__kmp_atomic_compare_store_acq(&lck->lk.poll, tas_free, tas_busy));114  KMP_FSYNC_ACQUIRED(lck);115  return KMP_LOCK_ACQUIRED_FIRST;116}117 118int __kmp_acquire_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) {119  int retval = __kmp_acquire_tas_lock_timed_template(lck, gtid);120  return retval;121}122 123static int __kmp_acquire_tas_lock_with_checks(kmp_tas_lock_t *lck,124                                              kmp_int32 gtid) {125  char const *const func = "omp_set_lock";126  if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) &&127      __kmp_is_tas_lock_nestable(lck)) {128    KMP_FATAL(LockNestableUsedAsSimple, func);129  }130  if ((gtid >= 0) && (__kmp_get_tas_lock_owner(lck) == gtid)) {131    KMP_FATAL(LockIsAlreadyOwned, func);132  }133  return __kmp_acquire_tas_lock(lck, gtid);134}135 136int __kmp_test_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) {137  kmp_int32 tas_free = KMP_LOCK_FREE(tas);138  kmp_int32 tas_busy = KMP_LOCK_BUSY(gtid + 1, tas);139  if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == tas_free &&140      __kmp_atomic_compare_store_acq(&lck->lk.poll, tas_free, tas_busy)) {141    KMP_FSYNC_ACQUIRED(lck);142    return TRUE;143  }144  return FALSE;145}146 147static int __kmp_test_tas_lock_with_checks(kmp_tas_lock_t *lck,148                                           kmp_int32 gtid) {149  char const *const func = "omp_test_lock";150  if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) &&151      __kmp_is_tas_lock_nestable(lck)) {152    KMP_FATAL(LockNestableUsedAsSimple, func);153  }154  return __kmp_test_tas_lock(lck, gtid);155}156 157int __kmp_release_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) {158  KMP_MB(); /* Flush all pending memory write invalidates.  */159 160  KMP_FSYNC_RELEASING(lck);161  KMP_ATOMIC_ST_REL(&lck->lk.poll, KMP_LOCK_FREE(tas));162  KMP_MB(); /* Flush all pending memory write invalidates.  */163 164  KMP_YIELD_OVERSUB();165  return KMP_LOCK_RELEASED;166}167 168static int __kmp_release_tas_lock_with_checks(kmp_tas_lock_t *lck,169                                              kmp_int32 gtid) {170  char const *const func = "omp_unset_lock";171  KMP_MB(); /* in case another processor initialized lock */172  if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) &&173      __kmp_is_tas_lock_nestable(lck)) {174    KMP_FATAL(LockNestableUsedAsSimple, func);175  }176  if (__kmp_get_tas_lock_owner(lck) == -1) {177    KMP_FATAL(LockUnsettingFree, func);178  }179  if ((gtid >= 0) && (__kmp_get_tas_lock_owner(lck) >= 0) &&180      (__kmp_get_tas_lock_owner(lck) != gtid)) {181    KMP_FATAL(LockUnsettingSetByAnother, func);182  }183  return __kmp_release_tas_lock(lck, gtid);184}185 186void __kmp_init_tas_lock(kmp_tas_lock_t *lck) {187  lck->lk.poll = KMP_LOCK_FREE(tas);188}189 190void __kmp_destroy_tas_lock(kmp_tas_lock_t *lck) { lck->lk.poll = 0; }191 192static void __kmp_destroy_tas_lock_with_checks(kmp_tas_lock_t *lck) {193  char const *const func = "omp_destroy_lock";194  if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) &&195      __kmp_is_tas_lock_nestable(lck)) {196    KMP_FATAL(LockNestableUsedAsSimple, func);197  }198  if (__kmp_get_tas_lock_owner(lck) != -1) {199    KMP_FATAL(LockStillOwned, func);200  }201  __kmp_destroy_tas_lock(lck);202}203 204// nested test and set locks205 206int __kmp_acquire_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) {207  KMP_DEBUG_ASSERT(gtid >= 0);208 209  if (__kmp_get_tas_lock_owner(lck) == gtid) {210    lck->lk.depth_locked += 1;211    return KMP_LOCK_ACQUIRED_NEXT;212  } else {213    __kmp_acquire_tas_lock_timed_template(lck, gtid);214    lck->lk.depth_locked = 1;215    return KMP_LOCK_ACQUIRED_FIRST;216  }217}218 219static int __kmp_acquire_nested_tas_lock_with_checks(kmp_tas_lock_t *lck,220                                                     kmp_int32 gtid) {221  char const *const func = "omp_set_nest_lock";222  if (!__kmp_is_tas_lock_nestable(lck)) {223    KMP_FATAL(LockSimpleUsedAsNestable, func);224  }225  return __kmp_acquire_nested_tas_lock(lck, gtid);226}227 228int __kmp_test_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) {229  int retval;230 231  KMP_DEBUG_ASSERT(gtid >= 0);232 233  if (__kmp_get_tas_lock_owner(lck) == gtid) {234    retval = ++lck->lk.depth_locked;235  } else if (!__kmp_test_tas_lock(lck, gtid)) {236    retval = 0;237  } else {238    KMP_MB();239    retval = lck->lk.depth_locked = 1;240  }241  return retval;242}243 244static int __kmp_test_nested_tas_lock_with_checks(kmp_tas_lock_t *lck,245                                                  kmp_int32 gtid) {246  char const *const func = "omp_test_nest_lock";247  if (!__kmp_is_tas_lock_nestable(lck)) {248    KMP_FATAL(LockSimpleUsedAsNestable, func);249  }250  return __kmp_test_nested_tas_lock(lck, gtid);251}252 253int __kmp_release_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) {254  KMP_DEBUG_ASSERT(gtid >= 0);255 256  KMP_MB();257  if (--(lck->lk.depth_locked) == 0) {258    __kmp_release_tas_lock(lck, gtid);259    return KMP_LOCK_RELEASED;260  }261  return KMP_LOCK_STILL_HELD;262}263 264static int __kmp_release_nested_tas_lock_with_checks(kmp_tas_lock_t *lck,265                                                     kmp_int32 gtid) {266  char const *const func = "omp_unset_nest_lock";267  KMP_MB(); /* in case another processor initialized lock */268  if (!__kmp_is_tas_lock_nestable(lck)) {269    KMP_FATAL(LockSimpleUsedAsNestable, func);270  }271  if (__kmp_get_tas_lock_owner(lck) == -1) {272    KMP_FATAL(LockUnsettingFree, func);273  }274  if (__kmp_get_tas_lock_owner(lck) != gtid) {275    KMP_FATAL(LockUnsettingSetByAnother, func);276  }277  return __kmp_release_nested_tas_lock(lck, gtid);278}279 280void __kmp_init_nested_tas_lock(kmp_tas_lock_t *lck) {281  __kmp_init_tas_lock(lck);282  lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks283}284 285void __kmp_destroy_nested_tas_lock(kmp_tas_lock_t *lck) {286  __kmp_destroy_tas_lock(lck);287  lck->lk.depth_locked = 0;288}289 290static void __kmp_destroy_nested_tas_lock_with_checks(kmp_tas_lock_t *lck) {291  char const *const func = "omp_destroy_nest_lock";292  if (!__kmp_is_tas_lock_nestable(lck)) {293    KMP_FATAL(LockSimpleUsedAsNestable, func);294  }295  if (__kmp_get_tas_lock_owner(lck) != -1) {296    KMP_FATAL(LockStillOwned, func);297  }298  __kmp_destroy_nested_tas_lock(lck);299}300 301#if KMP_USE_FUTEX302 303/* ------------------------------------------------------------------------ */304/* futex locks */305 306// futex locks are really just test and set locks, with a different method307// of handling contention.  They take the same amount of space as test and308// set locks, and are allocated the same way (i.e. use the area allocated by309// the compiler for non-nested locks / allocate nested locks on the heap).310 311static kmp_int32 __kmp_get_futex_lock_owner(kmp_futex_lock_t *lck) {312  return KMP_LOCK_STRIP((TCR_4(lck->lk.poll) >> 1)) - 1;313}314 315static inline bool __kmp_is_futex_lock_nestable(kmp_futex_lock_t *lck) {316  return lck->lk.depth_locked != -1;317}318 319__forceinline static int320__kmp_acquire_futex_lock_timed_template(kmp_futex_lock_t *lck, kmp_int32 gtid) {321  kmp_int32 gtid_code = (gtid + 1) << 1;322 323  KMP_MB();324 325#ifdef USE_LOCK_PROFILE326  kmp_uint32 curr = KMP_LOCK_STRIP(TCR_4(lck->lk.poll));327  if ((curr != 0) && (curr != gtid_code))328    __kmp_printf("LOCK CONTENTION: %p\n", lck);329/* else __kmp_printf( "." );*/330#endif /* USE_LOCK_PROFILE */331 332  KMP_FSYNC_PREPARE(lck);333  KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d entering\n",334                  lck, lck->lk.poll, gtid));335 336  kmp_int32 poll_val;337 338  while ((poll_val = KMP_COMPARE_AND_STORE_RET32(339              &(lck->lk.poll), KMP_LOCK_FREE(futex),340              KMP_LOCK_BUSY(gtid_code, futex))) != KMP_LOCK_FREE(futex)) {341 342    kmp_int32 cond = KMP_LOCK_STRIP(poll_val) & 1;343    KA_TRACE(344        1000,345        ("__kmp_acquire_futex_lock: lck:%p, T#%d poll_val = 0x%x cond = 0x%x\n",346         lck, gtid, poll_val, cond));347 348    // NOTE: if you try to use the following condition for this branch349    //350    // if ( poll_val & 1 == 0 )351    //352    // Then the 12.0 compiler has a bug where the following block will353    // always be skipped, regardless of the value of the LSB of poll_val.354    if (!cond) {355      // Try to set the lsb in the poll to indicate to the owner356      // thread that they need to wake this thread up.357      if (!KMP_COMPARE_AND_STORE_REL32(&(lck->lk.poll), poll_val,358                                       poll_val | KMP_LOCK_BUSY(1, futex))) {359        KA_TRACE(360            1000,361            ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d can't set bit 0\n",362             lck, lck->lk.poll, gtid));363        continue;364      }365      poll_val |= KMP_LOCK_BUSY(1, futex);366 367      KA_TRACE(1000,368               ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d bit 0 set\n", lck,369                lck->lk.poll, gtid));370    }371 372    KA_TRACE(373        1000,374        ("__kmp_acquire_futex_lock: lck:%p, T#%d before futex_wait(0x%x)\n",375         lck, gtid, poll_val));376 377    long rc;378    if ((rc = syscall(__NR_futex, &(lck->lk.poll), FUTEX_WAIT, poll_val, NULL,379                      NULL, 0)) != 0) {380      KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p, T#%d futex_wait(0x%x) "381                      "failed (rc=%ld errno=%d)\n",382                      lck, gtid, poll_val, rc, errno));383      continue;384    }385 386    KA_TRACE(1000,387             ("__kmp_acquire_futex_lock: lck:%p, T#%d after futex_wait(0x%x)\n",388              lck, gtid, poll_val));389    // This thread has now done a successful futex wait call and was entered on390    // the OS futex queue.  We must now perform a futex wake call when releasing391    // the lock, as we have no idea how many other threads are in the queue.392    gtid_code |= 1;393  }394 395  KMP_FSYNC_ACQUIRED(lck);396  KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d exiting\n", lck,397                  lck->lk.poll, gtid));398  return KMP_LOCK_ACQUIRED_FIRST;399}400 401int __kmp_acquire_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) {402  int retval = __kmp_acquire_futex_lock_timed_template(lck, gtid);403  return retval;404}405 406static int __kmp_acquire_futex_lock_with_checks(kmp_futex_lock_t *lck,407                                                kmp_int32 gtid) {408  char const *const func = "omp_set_lock";409  if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) &&410      __kmp_is_futex_lock_nestable(lck)) {411    KMP_FATAL(LockNestableUsedAsSimple, func);412  }413  if ((gtid >= 0) && (__kmp_get_futex_lock_owner(lck) == gtid)) {414    KMP_FATAL(LockIsAlreadyOwned, func);415  }416  return __kmp_acquire_futex_lock(lck, gtid);417}418 419int __kmp_test_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) {420  if (KMP_COMPARE_AND_STORE_ACQ32(&(lck->lk.poll), KMP_LOCK_FREE(futex),421                                  KMP_LOCK_BUSY((gtid + 1) << 1, futex))) {422    KMP_FSYNC_ACQUIRED(lck);423    return TRUE;424  }425  return FALSE;426}427 428static int __kmp_test_futex_lock_with_checks(kmp_futex_lock_t *lck,429                                             kmp_int32 gtid) {430  char const *const func = "omp_test_lock";431  if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) &&432      __kmp_is_futex_lock_nestable(lck)) {433    KMP_FATAL(LockNestableUsedAsSimple, func);434  }435  return __kmp_test_futex_lock(lck, gtid);436}437 438int __kmp_release_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) {439  KMP_MB(); /* Flush all pending memory write invalidates.  */440 441  KA_TRACE(1000, ("__kmp_release_futex_lock: lck:%p(0x%x), T#%d entering\n",442                  lck, lck->lk.poll, gtid));443 444  KMP_FSYNC_RELEASING(lck);445 446  kmp_int32 poll_val = KMP_XCHG_FIXED32(&(lck->lk.poll), KMP_LOCK_FREE(futex));447 448  KA_TRACE(1000,449           ("__kmp_release_futex_lock: lck:%p, T#%d released poll_val = 0x%x\n",450            lck, gtid, poll_val));451 452  if (KMP_LOCK_STRIP(poll_val) & 1) {453    KA_TRACE(1000,454             ("__kmp_release_futex_lock: lck:%p, T#%d futex_wake 1 thread\n",455              lck, gtid));456    syscall(__NR_futex, &(lck->lk.poll), FUTEX_WAKE, KMP_LOCK_BUSY(1, futex),457            NULL, NULL, 0);458  }459 460  KMP_MB(); /* Flush all pending memory write invalidates.  */461 462  KA_TRACE(1000, ("__kmp_release_futex_lock: lck:%p(0x%x), T#%d exiting\n", lck,463                  lck->lk.poll, gtid));464 465  KMP_YIELD_OVERSUB();466  return KMP_LOCK_RELEASED;467}468 469static int __kmp_release_futex_lock_with_checks(kmp_futex_lock_t *lck,470                                                kmp_int32 gtid) {471  char const *const func = "omp_unset_lock";472  KMP_MB(); /* in case another processor initialized lock */473  if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) &&474      __kmp_is_futex_lock_nestable(lck)) {475    KMP_FATAL(LockNestableUsedAsSimple, func);476  }477  if (__kmp_get_futex_lock_owner(lck) == -1) {478    KMP_FATAL(LockUnsettingFree, func);479  }480  if ((gtid >= 0) && (__kmp_get_futex_lock_owner(lck) >= 0) &&481      (__kmp_get_futex_lock_owner(lck) != gtid)) {482    KMP_FATAL(LockUnsettingSetByAnother, func);483  }484  return __kmp_release_futex_lock(lck, gtid);485}486 487void __kmp_init_futex_lock(kmp_futex_lock_t *lck) {488  TCW_4(lck->lk.poll, KMP_LOCK_FREE(futex));489}490 491void __kmp_destroy_futex_lock(kmp_futex_lock_t *lck) { lck->lk.poll = 0; }492 493static void __kmp_destroy_futex_lock_with_checks(kmp_futex_lock_t *lck) {494  char const *const func = "omp_destroy_lock";495  if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) &&496      __kmp_is_futex_lock_nestable(lck)) {497    KMP_FATAL(LockNestableUsedAsSimple, func);498  }499  if (__kmp_get_futex_lock_owner(lck) != -1) {500    KMP_FATAL(LockStillOwned, func);501  }502  __kmp_destroy_futex_lock(lck);503}504 505// nested futex locks506 507int __kmp_acquire_nested_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) {508  KMP_DEBUG_ASSERT(gtid >= 0);509 510  if (__kmp_get_futex_lock_owner(lck) == gtid) {511    lck->lk.depth_locked += 1;512    return KMP_LOCK_ACQUIRED_NEXT;513  } else {514    __kmp_acquire_futex_lock_timed_template(lck, gtid);515    lck->lk.depth_locked = 1;516    return KMP_LOCK_ACQUIRED_FIRST;517  }518}519 520static int __kmp_acquire_nested_futex_lock_with_checks(kmp_futex_lock_t *lck,521                                                       kmp_int32 gtid) {522  char const *const func = "omp_set_nest_lock";523  if (!__kmp_is_futex_lock_nestable(lck)) {524    KMP_FATAL(LockSimpleUsedAsNestable, func);525  }526  return __kmp_acquire_nested_futex_lock(lck, gtid);527}528 529int __kmp_test_nested_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) {530  int retval;531 532  KMP_DEBUG_ASSERT(gtid >= 0);533 534  if (__kmp_get_futex_lock_owner(lck) == gtid) {535    retval = ++lck->lk.depth_locked;536  } else if (!__kmp_test_futex_lock(lck, gtid)) {537    retval = 0;538  } else {539    KMP_MB();540    retval = lck->lk.depth_locked = 1;541  }542  return retval;543}544 545static int __kmp_test_nested_futex_lock_with_checks(kmp_futex_lock_t *lck,546                                                    kmp_int32 gtid) {547  char const *const func = "omp_test_nest_lock";548  if (!__kmp_is_futex_lock_nestable(lck)) {549    KMP_FATAL(LockSimpleUsedAsNestable, func);550  }551  return __kmp_test_nested_futex_lock(lck, gtid);552}553 554int __kmp_release_nested_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) {555  KMP_DEBUG_ASSERT(gtid >= 0);556 557  KMP_MB();558  if (--(lck->lk.depth_locked) == 0) {559    __kmp_release_futex_lock(lck, gtid);560    return KMP_LOCK_RELEASED;561  }562  return KMP_LOCK_STILL_HELD;563}564 565static int __kmp_release_nested_futex_lock_with_checks(kmp_futex_lock_t *lck,566                                                       kmp_int32 gtid) {567  char const *const func = "omp_unset_nest_lock";568  KMP_MB(); /* in case another processor initialized lock */569  if (!__kmp_is_futex_lock_nestable(lck)) {570    KMP_FATAL(LockSimpleUsedAsNestable, func);571  }572  if (__kmp_get_futex_lock_owner(lck) == -1) {573    KMP_FATAL(LockUnsettingFree, func);574  }575  if (__kmp_get_futex_lock_owner(lck) != gtid) {576    KMP_FATAL(LockUnsettingSetByAnother, func);577  }578  return __kmp_release_nested_futex_lock(lck, gtid);579}580 581void __kmp_init_nested_futex_lock(kmp_futex_lock_t *lck) {582  __kmp_init_futex_lock(lck);583  lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks584}585 586void __kmp_destroy_nested_futex_lock(kmp_futex_lock_t *lck) {587  __kmp_destroy_futex_lock(lck);588  lck->lk.depth_locked = 0;589}590 591static void __kmp_destroy_nested_futex_lock_with_checks(kmp_futex_lock_t *lck) {592  char const *const func = "omp_destroy_nest_lock";593  if (!__kmp_is_futex_lock_nestable(lck)) {594    KMP_FATAL(LockSimpleUsedAsNestable, func);595  }596  if (__kmp_get_futex_lock_owner(lck) != -1) {597    KMP_FATAL(LockStillOwned, func);598  }599  __kmp_destroy_nested_futex_lock(lck);600}601 602#endif // KMP_USE_FUTEX603 604/* ------------------------------------------------------------------------ */605/* ticket (bakery) locks */606 607static kmp_int32 __kmp_get_ticket_lock_owner(kmp_ticket_lock_t *lck) {608  return std::atomic_load_explicit(&lck->lk.owner_id,609                                   std::memory_order_relaxed) -610         1;611}612 613static inline bool __kmp_is_ticket_lock_nestable(kmp_ticket_lock_t *lck) {614  return std::atomic_load_explicit(&lck->lk.depth_locked,615                                   std::memory_order_relaxed) != -1;616}617 618static kmp_uint32 __kmp_bakery_check(void *now_serving, kmp_uint32 my_ticket) {619  return std::atomic_load_explicit((std::atomic<unsigned> *)now_serving,620                                   std::memory_order_acquire) == my_ticket;621}622 623__forceinline static int624__kmp_acquire_ticket_lock_timed_template(kmp_ticket_lock_t *lck,625                                         kmp_int32 gtid) {626  kmp_uint32 my_ticket = std::atomic_fetch_add_explicit(627      &lck->lk.next_ticket, 1U, std::memory_order_relaxed);628 629#ifdef USE_LOCK_PROFILE630  if (std::atomic_load_explicit(&lck->lk.now_serving,631                                std::memory_order_relaxed) != my_ticket)632    __kmp_printf("LOCK CONTENTION: %p\n", lck);633/* else __kmp_printf( "." );*/634#endif /* USE_LOCK_PROFILE */635 636  if (std::atomic_load_explicit(&lck->lk.now_serving,637                                std::memory_order_acquire) == my_ticket) {638    return KMP_LOCK_ACQUIRED_FIRST;639  }640  KMP_WAIT_PTR(&lck->lk.now_serving, my_ticket, __kmp_bakery_check, lck);641  return KMP_LOCK_ACQUIRED_FIRST;642}643 644int __kmp_acquire_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) {645  int retval = __kmp_acquire_ticket_lock_timed_template(lck, gtid);646  return retval;647}648 649static int __kmp_acquire_ticket_lock_with_checks(kmp_ticket_lock_t *lck,650                                                 kmp_int32 gtid) {651  char const *const func = "omp_set_lock";652 653  if (!std::atomic_load_explicit(&lck->lk.initialized,654                                 std::memory_order_relaxed)) {655    KMP_FATAL(LockIsUninitialized, func);656  }657  if (lck->lk.self != lck) {658    KMP_FATAL(LockIsUninitialized, func);659  }660  if (__kmp_is_ticket_lock_nestable(lck)) {661    KMP_FATAL(LockNestableUsedAsSimple, func);662  }663  if ((gtid >= 0) && (__kmp_get_ticket_lock_owner(lck) == gtid)) {664    KMP_FATAL(LockIsAlreadyOwned, func);665  }666 667  __kmp_acquire_ticket_lock(lck, gtid);668 669  std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1,670                             std::memory_order_relaxed);671  return KMP_LOCK_ACQUIRED_FIRST;672}673 674int __kmp_test_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) {675  kmp_uint32 my_ticket = std::atomic_load_explicit(&lck->lk.next_ticket,676                                                   std::memory_order_relaxed);677 678  if (std::atomic_load_explicit(&lck->lk.now_serving,679                                std::memory_order_relaxed) == my_ticket) {680    kmp_uint32 next_ticket = my_ticket + 1;681    if (std::atomic_compare_exchange_strong_explicit(682            &lck->lk.next_ticket, &my_ticket, next_ticket,683            std::memory_order_acquire, std::memory_order_acquire)) {684      return TRUE;685    }686  }687  return FALSE;688}689 690static int __kmp_test_ticket_lock_with_checks(kmp_ticket_lock_t *lck,691                                              kmp_int32 gtid) {692  char const *const func = "omp_test_lock";693 694  if (!std::atomic_load_explicit(&lck->lk.initialized,695                                 std::memory_order_relaxed)) {696    KMP_FATAL(LockIsUninitialized, func);697  }698  if (lck->lk.self != lck) {699    KMP_FATAL(LockIsUninitialized, func);700  }701  if (__kmp_is_ticket_lock_nestable(lck)) {702    KMP_FATAL(LockNestableUsedAsSimple, func);703  }704 705  int retval = __kmp_test_ticket_lock(lck, gtid);706 707  if (retval) {708    std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1,709                               std::memory_order_relaxed);710  }711  return retval;712}713 714int __kmp_release_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) {715  std::atomic_fetch_add_explicit(&lck->lk.now_serving, 1U,716                                 std::memory_order_release);717 718  return KMP_LOCK_RELEASED;719}720 721static int __kmp_release_ticket_lock_with_checks(kmp_ticket_lock_t *lck,722                                                 kmp_int32 gtid) {723  char const *const func = "omp_unset_lock";724 725  if (!std::atomic_load_explicit(&lck->lk.initialized,726                                 std::memory_order_relaxed)) {727    KMP_FATAL(LockIsUninitialized, func);728  }729  if (lck->lk.self != lck) {730    KMP_FATAL(LockIsUninitialized, func);731  }732  if (__kmp_is_ticket_lock_nestable(lck)) {733    KMP_FATAL(LockNestableUsedAsSimple, func);734  }735  if (__kmp_get_ticket_lock_owner(lck) == -1) {736    KMP_FATAL(LockUnsettingFree, func);737  }738  if ((gtid >= 0) && (__kmp_get_ticket_lock_owner(lck) >= 0) &&739      (__kmp_get_ticket_lock_owner(lck) != gtid)) {740    KMP_FATAL(LockUnsettingSetByAnother, func);741  }742  std::atomic_store_explicit(&lck->lk.owner_id, 0, std::memory_order_relaxed);743  return __kmp_release_ticket_lock(lck, gtid);744}745 746void __kmp_init_ticket_lock(kmp_ticket_lock_t *lck) {747  lck->lk.location = NULL;748  lck->lk.self = lck;749  std::atomic_store_explicit(&lck->lk.next_ticket, 0U,750                             std::memory_order_relaxed);751  std::atomic_store_explicit(&lck->lk.now_serving, 0U,752                             std::memory_order_relaxed);753  std::atomic_store_explicit(754      &lck->lk.owner_id, 0,755      std::memory_order_relaxed); // no thread owns the lock.756  std::atomic_store_explicit(757      &lck->lk.depth_locked, -1,758      std::memory_order_relaxed); // -1 => not a nested lock.759  std::atomic_store_explicit(&lck->lk.initialized, true,760                             std::memory_order_release);761}762 763void __kmp_destroy_ticket_lock(kmp_ticket_lock_t *lck) {764  std::atomic_store_explicit(&lck->lk.initialized, false,765                             std::memory_order_release);766  lck->lk.self = NULL;767  lck->lk.location = NULL;768  std::atomic_store_explicit(&lck->lk.next_ticket, 0U,769                             std::memory_order_relaxed);770  std::atomic_store_explicit(&lck->lk.now_serving, 0U,771                             std::memory_order_relaxed);772  std::atomic_store_explicit(&lck->lk.owner_id, 0, std::memory_order_relaxed);773  std::atomic_store_explicit(&lck->lk.depth_locked, -1,774                             std::memory_order_relaxed);775}776 777static void __kmp_destroy_ticket_lock_with_checks(kmp_ticket_lock_t *lck) {778  char const *const func = "omp_destroy_lock";779 780  if (!std::atomic_load_explicit(&lck->lk.initialized,781                                 std::memory_order_relaxed)) {782    KMP_FATAL(LockIsUninitialized, func);783  }784  if (lck->lk.self != lck) {785    KMP_FATAL(LockIsUninitialized, func);786  }787  if (__kmp_is_ticket_lock_nestable(lck)) {788    KMP_FATAL(LockNestableUsedAsSimple, func);789  }790  if (__kmp_get_ticket_lock_owner(lck) != -1) {791    KMP_FATAL(LockStillOwned, func);792  }793  __kmp_destroy_ticket_lock(lck);794}795 796// nested ticket locks797 798int __kmp_acquire_nested_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) {799  KMP_DEBUG_ASSERT(gtid >= 0);800 801  if (__kmp_get_ticket_lock_owner(lck) == gtid) {802    std::atomic_fetch_add_explicit(&lck->lk.depth_locked, 1,803                                   std::memory_order_relaxed);804    return KMP_LOCK_ACQUIRED_NEXT;805  } else {806    __kmp_acquire_ticket_lock_timed_template(lck, gtid);807    std::atomic_store_explicit(&lck->lk.depth_locked, 1,808                               std::memory_order_relaxed);809    std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1,810                               std::memory_order_relaxed);811    return KMP_LOCK_ACQUIRED_FIRST;812  }813}814 815static int __kmp_acquire_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck,816                                                        kmp_int32 gtid) {817  char const *const func = "omp_set_nest_lock";818 819  if (!std::atomic_load_explicit(&lck->lk.initialized,820                                 std::memory_order_relaxed)) {821    KMP_FATAL(LockIsUninitialized, func);822  }823  if (lck->lk.self != lck) {824    KMP_FATAL(LockIsUninitialized, func);825  }826  if (!__kmp_is_ticket_lock_nestable(lck)) {827    KMP_FATAL(LockSimpleUsedAsNestable, func);828  }829  return __kmp_acquire_nested_ticket_lock(lck, gtid);830}831 832int __kmp_test_nested_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) {833  int retval;834 835  KMP_DEBUG_ASSERT(gtid >= 0);836 837  if (__kmp_get_ticket_lock_owner(lck) == gtid) {838    retval = std::atomic_fetch_add_explicit(&lck->lk.depth_locked, 1,839                                            std::memory_order_relaxed) +840             1;841  } else if (!__kmp_test_ticket_lock(lck, gtid)) {842    retval = 0;843  } else {844    std::atomic_store_explicit(&lck->lk.depth_locked, 1,845                               std::memory_order_relaxed);846    std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1,847                               std::memory_order_relaxed);848    retval = 1;849  }850  return retval;851}852 853static int __kmp_test_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck,854                                                     kmp_int32 gtid) {855  char const *const func = "omp_test_nest_lock";856 857  if (!std::atomic_load_explicit(&lck->lk.initialized,858                                 std::memory_order_relaxed)) {859    KMP_FATAL(LockIsUninitialized, func);860  }861  if (lck->lk.self != lck) {862    KMP_FATAL(LockIsUninitialized, func);863  }864  if (!__kmp_is_ticket_lock_nestable(lck)) {865    KMP_FATAL(LockSimpleUsedAsNestable, func);866  }867  return __kmp_test_nested_ticket_lock(lck, gtid);868}869 870int __kmp_release_nested_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) {871  KMP_DEBUG_ASSERT(gtid >= 0);872 873  if ((std::atomic_fetch_add_explicit(&lck->lk.depth_locked, -1,874                                      std::memory_order_relaxed) -875       1) == 0) {876    std::atomic_store_explicit(&lck->lk.owner_id, 0, std::memory_order_relaxed);877    __kmp_release_ticket_lock(lck, gtid);878    return KMP_LOCK_RELEASED;879  }880  return KMP_LOCK_STILL_HELD;881}882 883static int __kmp_release_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck,884                                                        kmp_int32 gtid) {885  char const *const func = "omp_unset_nest_lock";886 887  if (!std::atomic_load_explicit(&lck->lk.initialized,888                                 std::memory_order_relaxed)) {889    KMP_FATAL(LockIsUninitialized, func);890  }891  if (lck->lk.self != lck) {892    KMP_FATAL(LockIsUninitialized, func);893  }894  if (!__kmp_is_ticket_lock_nestable(lck)) {895    KMP_FATAL(LockSimpleUsedAsNestable, func);896  }897  if (__kmp_get_ticket_lock_owner(lck) == -1) {898    KMP_FATAL(LockUnsettingFree, func);899  }900  if (__kmp_get_ticket_lock_owner(lck) != gtid) {901    KMP_FATAL(LockUnsettingSetByAnother, func);902  }903  return __kmp_release_nested_ticket_lock(lck, gtid);904}905 906void __kmp_init_nested_ticket_lock(kmp_ticket_lock_t *lck) {907  __kmp_init_ticket_lock(lck);908  std::atomic_store_explicit(&lck->lk.depth_locked, 0,909                             std::memory_order_relaxed);910  // >= 0 for nestable locks, -1 for simple locks911}912 913void __kmp_destroy_nested_ticket_lock(kmp_ticket_lock_t *lck) {914  __kmp_destroy_ticket_lock(lck);915  std::atomic_store_explicit(&lck->lk.depth_locked, 0,916                             std::memory_order_relaxed);917}918 919static void920__kmp_destroy_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck) {921  char const *const func = "omp_destroy_nest_lock";922 923  if (!std::atomic_load_explicit(&lck->lk.initialized,924                                 std::memory_order_relaxed)) {925    KMP_FATAL(LockIsUninitialized, func);926  }927  if (lck->lk.self != lck) {928    KMP_FATAL(LockIsUninitialized, func);929  }930  if (!__kmp_is_ticket_lock_nestable(lck)) {931    KMP_FATAL(LockSimpleUsedAsNestable, func);932  }933  if (__kmp_get_ticket_lock_owner(lck) != -1) {934    KMP_FATAL(LockStillOwned, func);935  }936  __kmp_destroy_nested_ticket_lock(lck);937}938 939// access functions to fields which don't exist for all lock kinds.940 941static const ident_t *__kmp_get_ticket_lock_location(kmp_ticket_lock_t *lck) {942  return lck->lk.location;943}944 945static void __kmp_set_ticket_lock_location(kmp_ticket_lock_t *lck,946                                           const ident_t *loc) {947  lck->lk.location = loc;948}949 950static kmp_lock_flags_t __kmp_get_ticket_lock_flags(kmp_ticket_lock_t *lck) {951  return lck->lk.flags;952}953 954static void __kmp_set_ticket_lock_flags(kmp_ticket_lock_t *lck,955                                        kmp_lock_flags_t flags) {956  lck->lk.flags = flags;957}958 959/* ------------------------------------------------------------------------ */960/* queuing locks */961 962/* First the states963   (head,tail) =              0, 0  means lock is unheld, nobody on queue964                 UINT_MAX or -1, 0  means lock is held, nobody on queue965                              h, h  means lock held or about to transition,966                                    1 element on queue967                              h, t  h <> t, means lock is held or about to968                                    transition, >1 elements on queue969 970   Now the transitions971      Acquire(0,0)  = -1 ,0972      Release(0,0)  = Error973      Acquire(-1,0) =  h ,h    h > 0974      Release(-1,0) =  0 ,0975      Acquire(h,h)  =  h ,t    h > 0, t > 0, h <> t976      Release(h,h)  = -1 ,0    h > 0977      Acquire(h,t)  =  h ,t'   h > 0, t > 0, t' > 0, h <> t, h <> t', t <> t'978      Release(h,t)  =  h',t    h > 0, t > 0, h <> t, h <> h', h' maybe = t979 980   And pictorially981 982           +-----+983           | 0, 0|------- release -------> Error984           +-----+985             |  ^986      acquire|  |release987             |  |988             |  |989             v  |990           +-----+991           |-1, 0|992           +-----+993             |  ^994      acquire|  |release995             |  |996             |  |997             v  |998           +-----+999           | h, h|1000           +-----+1001             |  ^1002      acquire|  |release1003             |  |1004             |  |1005             v  |1006           +-----+1007           | h, t|----- acquire, release loopback ---+1008           +-----+                                   |1009                ^                                    |1010                |                                    |1011                +------------------------------------+1012 */1013 1014#ifdef DEBUG_QUEUING_LOCKS1015 1016/* Stuff for circular trace buffer */1017#define TRACE_BUF_ELE 10241018static char traces[TRACE_BUF_ELE][128] = {0};1019static int tc = 0;1020#define TRACE_LOCK(X, Y)                                                       \1021  KMP_SNPRINTF(traces[tc++ % TRACE_BUF_ELE], 128, "t%d at %s\n", X, Y);1022#define TRACE_LOCK_T(X, Y, Z)                                                  \1023  KMP_SNPRINTF(traces[tc++ % TRACE_BUF_ELE], 128, "t%d at %s%d\n", X, Y, Z);1024#define TRACE_LOCK_HT(X, Y, Z, Q)                                              \1025  KMP_SNPRINTF(traces[tc++ % TRACE_BUF_ELE], 128, "t%d at %s %d,%d\n", X, Y,   \1026               Z, Q);1027 1028static void __kmp_dump_queuing_lock(kmp_info_t *this_thr, kmp_int32 gtid,1029                                    kmp_queuing_lock_t *lck, kmp_int32 head_id,1030                                    kmp_int32 tail_id) {1031  kmp_int32 t, i;1032 1033  __kmp_printf_no_lock("\n__kmp_dump_queuing_lock: TRACE BEGINS HERE! \n");1034 1035  i = tc % TRACE_BUF_ELE;1036  __kmp_printf_no_lock("%s\n", traces[i]);1037  i = (i + 1) % TRACE_BUF_ELE;1038  while (i != (tc % TRACE_BUF_ELE)) {1039    __kmp_printf_no_lock("%s", traces[i]);1040    i = (i + 1) % TRACE_BUF_ELE;1041  }1042  __kmp_printf_no_lock("\n");1043 1044  __kmp_printf_no_lock("\n__kmp_dump_queuing_lock: gtid+1:%d, spin_here:%d, "1045                       "next_wait:%d, head_id:%d, tail_id:%d\n",1046                       gtid + 1, this_thr->th.th_spin_here,1047                       this_thr->th.th_next_waiting, head_id, tail_id);1048 1049  __kmp_printf_no_lock("\t\thead: %d ", lck->lk.head_id);1050 1051  if (lck->lk.head_id >= 1) {1052    t = __kmp_threads[lck->lk.head_id - 1]->th.th_next_waiting;1053    while (t > 0) {1054      __kmp_printf_no_lock("-> %d ", t);1055      t = __kmp_threads[t - 1]->th.th_next_waiting;1056    }1057  }1058  __kmp_printf_no_lock(";  tail: %d ", lck->lk.tail_id);1059  __kmp_printf_no_lock("\n\n");1060}1061 1062#endif /* DEBUG_QUEUING_LOCKS */1063 1064static kmp_int32 __kmp_get_queuing_lock_owner(kmp_queuing_lock_t *lck) {1065  return TCR_4(lck->lk.owner_id) - 1;1066}1067 1068static inline bool __kmp_is_queuing_lock_nestable(kmp_queuing_lock_t *lck) {1069  return lck->lk.depth_locked != -1;1070}1071 1072/* Acquire a lock using a the queuing lock implementation */1073template <bool takeTime>1074/* [TLW] The unused template above is left behind because of what BEB believes1075   is a potential compiler problem with __forceinline. */1076__forceinline static int1077__kmp_acquire_queuing_lock_timed_template(kmp_queuing_lock_t *lck,1078                                          kmp_int32 gtid) {1079  kmp_info_t *this_thr = __kmp_thread_from_gtid(gtid);1080  volatile kmp_int32 *head_id_p = &lck->lk.head_id;1081  volatile kmp_int32 *tail_id_p = &lck->lk.tail_id;1082  volatile kmp_uint32 *spin_here_p;1083 1084#if OMPT_SUPPORT1085  ompt_state_t prev_state = ompt_state_undefined;1086#endif1087 1088  KA_TRACE(1000,1089           ("__kmp_acquire_queuing_lock: lck:%p, T#%d entering\n", lck, gtid));1090 1091  KMP_FSYNC_PREPARE(lck);1092  KMP_DEBUG_ASSERT(this_thr != NULL);1093  spin_here_p = &this_thr->th.th_spin_here;1094 1095#ifdef DEBUG_QUEUING_LOCKS1096  TRACE_LOCK(gtid + 1, "acq ent");1097  if (*spin_here_p)1098    __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p);1099  if (this_thr->th.th_next_waiting != 0)1100    __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p);1101#endif1102  KMP_DEBUG_ASSERT(!*spin_here_p);1103  KMP_DEBUG_ASSERT(this_thr->th.th_next_waiting == 0);1104 1105  /* The following st.rel to spin_here_p needs to precede the cmpxchg.acq to1106     head_id_p that may follow, not just in execution order, but also in1107     visibility order. This way, when a releasing thread observes the changes to1108     the queue by this thread, it can rightly assume that spin_here_p has1109     already been set to TRUE, so that when it sets spin_here_p to FALSE, it is1110     not premature.  If the releasing thread sets spin_here_p to FALSE before1111     this thread sets it to TRUE, this thread will hang. */1112  *spin_here_p = TRUE; /* before enqueuing to prevent race */1113 1114  while (1) {1115    kmp_int32 enqueued;1116    kmp_int32 head;1117    kmp_int32 tail;1118 1119    head = *head_id_p;1120 1121    switch (head) {1122 1123    case -1: {1124#ifdef DEBUG_QUEUING_LOCKS1125      tail = *tail_id_p;1126      TRACE_LOCK_HT(gtid + 1, "acq read: ", head, tail);1127#endif1128      tail = 0; /* to make sure next link asynchronously read is not set1129                accidentally; this assignment prevents us from entering the1130                if ( t > 0 ) condition in the enqueued case below, which is not1131                necessary for this state transition */1132 1133      /* try (-1,0)->(tid,tid) */1134      enqueued = KMP_COMPARE_AND_STORE_ACQ64((volatile kmp_int64 *)tail_id_p,1135                                             KMP_PACK_64(-1, 0),1136                                             KMP_PACK_64(gtid + 1, gtid + 1));1137#ifdef DEBUG_QUEUING_LOCKS1138      if (enqueued)1139        TRACE_LOCK(gtid + 1, "acq enq: (-1,0)->(tid,tid)");1140#endif1141    } break;1142 1143    default: {1144      tail = *tail_id_p;1145      KMP_DEBUG_ASSERT(tail != gtid + 1);1146 1147#ifdef DEBUG_QUEUING_LOCKS1148      TRACE_LOCK_HT(gtid + 1, "acq read: ", head, tail);1149#endif1150 1151      if (tail == 0) {1152        enqueued = FALSE;1153      } else {1154        /* try (h,t) or (h,h)->(h,tid) */1155        enqueued = KMP_COMPARE_AND_STORE_ACQ32(tail_id_p, tail, gtid + 1);1156 1157#ifdef DEBUG_QUEUING_LOCKS1158        if (enqueued)1159          TRACE_LOCK(gtid + 1, "acq enq: (h,t)->(h,tid)");1160#endif1161      }1162    } break;1163 1164    case 0: /* empty queue */1165    {1166      kmp_int32 grabbed_lock;1167 1168#ifdef DEBUG_QUEUING_LOCKS1169      tail = *tail_id_p;1170      TRACE_LOCK_HT(gtid + 1, "acq read: ", head, tail);1171#endif1172      /* try (0,0)->(-1,0) */1173 1174      /* only legal transition out of head = 0 is head = -1 with no change to1175       * tail */1176      grabbed_lock = KMP_COMPARE_AND_STORE_ACQ32(head_id_p, 0, -1);1177 1178      if (grabbed_lock) {1179 1180        *spin_here_p = FALSE;1181 1182        KA_TRACE(1183            1000,1184            ("__kmp_acquire_queuing_lock: lck:%p, T#%d exiting: no queuing\n",1185             lck, gtid));1186#ifdef DEBUG_QUEUING_LOCKS1187        TRACE_LOCK_HT(gtid + 1, "acq exit: ", head, 0);1188#endif1189 1190#if OMPT_SUPPORT1191        if (ompt_enabled.enabled && prev_state != ompt_state_undefined) {1192          /* change the state before clearing wait_id */1193          this_thr->th.ompt_thread_info.state = prev_state;1194          this_thr->th.ompt_thread_info.wait_id = 0;1195        }1196#endif1197 1198        KMP_FSYNC_ACQUIRED(lck);1199        return KMP_LOCK_ACQUIRED_FIRST; /* lock holder cannot be on queue */1200      }1201      enqueued = FALSE;1202    } break;1203    }1204 1205#if OMPT_SUPPORT1206    if (ompt_enabled.enabled && prev_state == ompt_state_undefined) {1207      /* this thread will spin; set wait_id before entering wait state */1208      prev_state = this_thr->th.ompt_thread_info.state;1209      this_thr->th.ompt_thread_info.wait_id = (uint64_t)lck;1210      this_thr->th.ompt_thread_info.state = ompt_state_wait_lock;1211    }1212#endif1213 1214    if (enqueued) {1215      if (tail > 0) {1216        kmp_info_t *tail_thr = __kmp_thread_from_gtid(tail - 1);1217        KMP_ASSERT(tail_thr != NULL);1218        tail_thr->th.th_next_waiting = gtid + 1;1219        /* corresponding wait for this write in release code */1220      }1221      KA_TRACE(1000,1222               ("__kmp_acquire_queuing_lock: lck:%p, T#%d waiting for lock\n",1223                lck, gtid));1224 1225      KMP_MB();1226      // ToDo: Use __kmp_wait_sleep or similar when blocktime != inf1227      KMP_WAIT(spin_here_p, FALSE, KMP_EQ, lck);1228      // Synchronize writes to both runtime thread structures1229      // and writes in user code.1230      KMP_MB();1231 1232#ifdef DEBUG_QUEUING_LOCKS1233      TRACE_LOCK(gtid + 1, "acq spin");1234 1235      if (this_thr->th.th_next_waiting != 0)1236        __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p);1237#endif1238      KMP_DEBUG_ASSERT(this_thr->th.th_next_waiting == 0);1239      KA_TRACE(1000, ("__kmp_acquire_queuing_lock: lck:%p, T#%d exiting: after "1240                      "waiting on queue\n",1241                      lck, gtid));1242 1243#ifdef DEBUG_QUEUING_LOCKS1244      TRACE_LOCK(gtid + 1, "acq exit 2");1245#endif1246 1247#if OMPT_SUPPORT1248      /* change the state before clearing wait_id */1249      this_thr->th.ompt_thread_info.state = prev_state;1250      this_thr->th.ompt_thread_info.wait_id = 0;1251#endif1252 1253      /* got lock, we were dequeued by the thread that released lock */1254      return KMP_LOCK_ACQUIRED_FIRST;1255    }1256 1257    /* Yield if number of threads > number of logical processors */1258    /* ToDo: Not sure why this should only be in oversubscription case,1259       maybe should be traditional YIELD_INIT/YIELD_WHEN loop */1260    KMP_YIELD_OVERSUB();1261 1262#ifdef DEBUG_QUEUING_LOCKS1263    TRACE_LOCK(gtid + 1, "acq retry");1264#endif1265  }1266  KMP_ASSERT2(0, "should not get here");1267  return KMP_LOCK_ACQUIRED_FIRST;1268}1269 1270int __kmp_acquire_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) {1271  KMP_DEBUG_ASSERT(gtid >= 0);1272 1273  int retval = __kmp_acquire_queuing_lock_timed_template<false>(lck, gtid);1274  return retval;1275}1276 1277static int __kmp_acquire_queuing_lock_with_checks(kmp_queuing_lock_t *lck,1278                                                  kmp_int32 gtid) {1279  char const *const func = "omp_set_lock";1280  if (lck->lk.initialized != lck) {1281    KMP_FATAL(LockIsUninitialized, func);1282  }1283  if (__kmp_is_queuing_lock_nestable(lck)) {1284    KMP_FATAL(LockNestableUsedAsSimple, func);1285  }1286  if (__kmp_get_queuing_lock_owner(lck) == gtid) {1287    KMP_FATAL(LockIsAlreadyOwned, func);1288  }1289 1290  __kmp_acquire_queuing_lock(lck, gtid);1291 1292  lck->lk.owner_id = gtid + 1;1293  return KMP_LOCK_ACQUIRED_FIRST;1294}1295 1296int __kmp_test_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) {1297  volatile kmp_int32 *head_id_p = &lck->lk.head_id;1298  kmp_int32 head;1299#ifdef KMP_DEBUG1300  kmp_info_t *this_thr;1301#endif1302 1303  KA_TRACE(1000, ("__kmp_test_queuing_lock: T#%d entering\n", gtid));1304  KMP_DEBUG_ASSERT(gtid >= 0);1305#ifdef KMP_DEBUG1306  this_thr = __kmp_thread_from_gtid(gtid);1307  KMP_DEBUG_ASSERT(this_thr != NULL);1308  KMP_DEBUG_ASSERT(!this_thr->th.th_spin_here);1309#endif1310 1311  head = *head_id_p;1312 1313  if (head == 0) { /* nobody on queue, nobody holding */1314    /* try (0,0)->(-1,0) */1315    if (KMP_COMPARE_AND_STORE_ACQ32(head_id_p, 0, -1)) {1316      KA_TRACE(1000,1317               ("__kmp_test_queuing_lock: T#%d exiting: holding lock\n", gtid));1318      KMP_FSYNC_ACQUIRED(lck);1319      return TRUE;1320    }1321  }1322 1323  KA_TRACE(1000,1324           ("__kmp_test_queuing_lock: T#%d exiting: without lock\n", gtid));1325  return FALSE;1326}1327 1328static int __kmp_test_queuing_lock_with_checks(kmp_queuing_lock_t *lck,1329                                               kmp_int32 gtid) {1330  char const *const func = "omp_test_lock";1331  if (lck->lk.initialized != lck) {1332    KMP_FATAL(LockIsUninitialized, func);1333  }1334  if (__kmp_is_queuing_lock_nestable(lck)) {1335    KMP_FATAL(LockNestableUsedAsSimple, func);1336  }1337 1338  int retval = __kmp_test_queuing_lock(lck, gtid);1339 1340  if (retval) {1341    lck->lk.owner_id = gtid + 1;1342  }1343  return retval;1344}1345 1346int __kmp_release_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) {1347  volatile kmp_int32 *head_id_p = &lck->lk.head_id;1348  volatile kmp_int32 *tail_id_p = &lck->lk.tail_id;1349 1350  KA_TRACE(1000,1351           ("__kmp_release_queuing_lock: lck:%p, T#%d entering\n", lck, gtid));1352  KMP_DEBUG_ASSERT(gtid >= 0);1353#if KMP_DEBUG || DEBUG_QUEUING_LOCKS1354  kmp_info_t *this_thr = __kmp_thread_from_gtid(gtid);1355#endif1356  KMP_DEBUG_ASSERT(this_thr != NULL);1357#ifdef DEBUG_QUEUING_LOCKS1358  TRACE_LOCK(gtid + 1, "rel ent");1359 1360  if (this_thr->th.th_spin_here)1361    __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p);1362  if (this_thr->th.th_next_waiting != 0)1363    __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p);1364#endif1365  KMP_DEBUG_ASSERT(!this_thr->th.th_spin_here);1366  KMP_DEBUG_ASSERT(this_thr->th.th_next_waiting == 0);1367 1368  KMP_FSYNC_RELEASING(lck);1369 1370  while (1) {1371    kmp_int32 dequeued;1372    kmp_int32 head;1373    kmp_int32 tail;1374 1375    head = *head_id_p;1376 1377#ifdef DEBUG_QUEUING_LOCKS1378    tail = *tail_id_p;1379    TRACE_LOCK_HT(gtid + 1, "rel read: ", head, tail);1380    if (head == 0)1381      __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail);1382#endif1383    KMP_DEBUG_ASSERT(head !=1384                     0); /* holding the lock, head must be -1 or queue head */1385 1386    if (head == -1) { /* nobody on queue */1387      /* try (-1,0)->(0,0) */1388      if (KMP_COMPARE_AND_STORE_REL32(head_id_p, -1, 0)) {1389        KA_TRACE(1390            1000,1391            ("__kmp_release_queuing_lock: lck:%p, T#%d exiting: queue empty\n",1392             lck, gtid));1393#ifdef DEBUG_QUEUING_LOCKS1394        TRACE_LOCK_HT(gtid + 1, "rel exit: ", 0, 0);1395#endif1396 1397#if OMPT_SUPPORT1398/* nothing to do - no other thread is trying to shift blame */1399#endif1400        return KMP_LOCK_RELEASED;1401      }1402      dequeued = FALSE;1403    } else {1404      KMP_MB();1405      tail = *tail_id_p;1406      if (head == tail) { /* only one thread on the queue */1407#ifdef DEBUG_QUEUING_LOCKS1408        if (head <= 0)1409          __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail);1410#endif1411        KMP_DEBUG_ASSERT(head > 0);1412 1413        /* try (h,h)->(-1,0) */1414        dequeued = KMP_COMPARE_AND_STORE_REL64(1415            RCAST(volatile kmp_int64 *, tail_id_p), KMP_PACK_64(head, head),1416            KMP_PACK_64(-1, 0));1417#ifdef DEBUG_QUEUING_LOCKS1418        TRACE_LOCK(gtid + 1, "rel deq: (h,h)->(-1,0)");1419#endif1420 1421      } else {1422        volatile kmp_int32 *waiting_id_p;1423        kmp_info_t *head_thr = __kmp_thread_from_gtid(head - 1);1424        KMP_DEBUG_ASSERT(head_thr != NULL);1425        waiting_id_p = &head_thr->th.th_next_waiting;1426 1427/* Does this require synchronous reads? */1428#ifdef DEBUG_QUEUING_LOCKS1429        if (head <= 0 || tail <= 0)1430          __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail);1431#endif1432        KMP_DEBUG_ASSERT(head > 0 && tail > 0);1433 1434        /* try (h,t)->(h',t) or (t,t) */1435        KMP_MB();1436        /* make sure enqueuing thread has time to update next waiting thread1437         * field */1438        *head_id_p =1439            KMP_WAIT((volatile kmp_uint32 *)waiting_id_p, 0, KMP_NEQ, NULL);1440#ifdef DEBUG_QUEUING_LOCKS1441        TRACE_LOCK(gtid + 1, "rel deq: (h,t)->(h',t)");1442#endif1443        dequeued = TRUE;1444      }1445    }1446 1447    if (dequeued) {1448      kmp_info_t *head_thr = __kmp_thread_from_gtid(head - 1);1449      KMP_DEBUG_ASSERT(head_thr != NULL);1450 1451/* Does this require synchronous reads? */1452#ifdef DEBUG_QUEUING_LOCKS1453      if (head <= 0 || tail <= 0)1454        __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail);1455#endif1456      KMP_DEBUG_ASSERT(head > 0 && tail > 0);1457 1458      /* For clean code only. Thread not released until next statement prevents1459         race with acquire code. */1460      head_thr->th.th_next_waiting = 0;1461#ifdef DEBUG_QUEUING_LOCKS1462      TRACE_LOCK_T(gtid + 1, "rel nw=0 for t=", head);1463#endif1464 1465      KMP_MB();1466      /* reset spin value */1467      head_thr->th.th_spin_here = FALSE;1468 1469      KA_TRACE(1000, ("__kmp_release_queuing_lock: lck:%p, T#%d exiting: after "1470                      "dequeuing\n",1471                      lck, gtid));1472#ifdef DEBUG_QUEUING_LOCKS1473      TRACE_LOCK(gtid + 1, "rel exit 2");1474#endif1475      return KMP_LOCK_RELEASED;1476    }1477    /* KMP_CPU_PAUSE(); don't want to make releasing thread hold up acquiring1478       threads */1479 1480#ifdef DEBUG_QUEUING_LOCKS1481    TRACE_LOCK(gtid + 1, "rel retry");1482#endif1483 1484  } /* while */1485  KMP_ASSERT2(0, "should not get here");1486  return KMP_LOCK_RELEASED;1487}1488 1489static int __kmp_release_queuing_lock_with_checks(kmp_queuing_lock_t *lck,1490                                                  kmp_int32 gtid) {1491  char const *const func = "omp_unset_lock";1492  KMP_MB(); /* in case another processor initialized lock */1493  if (lck->lk.initialized != lck) {1494    KMP_FATAL(LockIsUninitialized, func);1495  }1496  if (__kmp_is_queuing_lock_nestable(lck)) {1497    KMP_FATAL(LockNestableUsedAsSimple, func);1498  }1499  if (__kmp_get_queuing_lock_owner(lck) == -1) {1500    KMP_FATAL(LockUnsettingFree, func);1501  }1502  if (__kmp_get_queuing_lock_owner(lck) != gtid) {1503    KMP_FATAL(LockUnsettingSetByAnother, func);1504  }1505  lck->lk.owner_id = 0;1506  return __kmp_release_queuing_lock(lck, gtid);1507}1508 1509void __kmp_init_queuing_lock(kmp_queuing_lock_t *lck) {1510  lck->lk.location = NULL;1511  lck->lk.head_id = 0;1512  lck->lk.tail_id = 0;1513  lck->lk.next_ticket = 0;1514  lck->lk.now_serving = 0;1515  lck->lk.owner_id = 0; // no thread owns the lock.1516  lck->lk.depth_locked = -1; // >= 0 for nestable locks, -1 for simple locks.1517  lck->lk.initialized = lck;1518 1519  KA_TRACE(1000, ("__kmp_init_queuing_lock: lock %p initialized\n", lck));1520}1521 1522void __kmp_destroy_queuing_lock(kmp_queuing_lock_t *lck) {1523  lck->lk.initialized = NULL;1524  lck->lk.location = NULL;1525  lck->lk.head_id = 0;1526  lck->lk.tail_id = 0;1527  lck->lk.next_ticket = 0;1528  lck->lk.now_serving = 0;1529  lck->lk.owner_id = 0;1530  lck->lk.depth_locked = -1;1531}1532 1533static void __kmp_destroy_queuing_lock_with_checks(kmp_queuing_lock_t *lck) {1534  char const *const func = "omp_destroy_lock";1535  if (lck->lk.initialized != lck) {1536    KMP_FATAL(LockIsUninitialized, func);1537  }1538  if (__kmp_is_queuing_lock_nestable(lck)) {1539    KMP_FATAL(LockNestableUsedAsSimple, func);1540  }1541  if (__kmp_get_queuing_lock_owner(lck) != -1) {1542    KMP_FATAL(LockStillOwned, func);1543  }1544  __kmp_destroy_queuing_lock(lck);1545}1546 1547// nested queuing locks1548 1549int __kmp_acquire_nested_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) {1550  KMP_DEBUG_ASSERT(gtid >= 0);1551 1552  if (__kmp_get_queuing_lock_owner(lck) == gtid) {1553    lck->lk.depth_locked += 1;1554    return KMP_LOCK_ACQUIRED_NEXT;1555  } else {1556    __kmp_acquire_queuing_lock_timed_template<false>(lck, gtid);1557    KMP_MB();1558    lck->lk.depth_locked = 1;1559    KMP_MB();1560    lck->lk.owner_id = gtid + 1;1561    return KMP_LOCK_ACQUIRED_FIRST;1562  }1563}1564 1565static int1566__kmp_acquire_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck,1567                                              kmp_int32 gtid) {1568  char const *const func = "omp_set_nest_lock";1569  if (lck->lk.initialized != lck) {1570    KMP_FATAL(LockIsUninitialized, func);1571  }1572  if (!__kmp_is_queuing_lock_nestable(lck)) {1573    KMP_FATAL(LockSimpleUsedAsNestable, func);1574  }1575  return __kmp_acquire_nested_queuing_lock(lck, gtid);1576}1577 1578int __kmp_test_nested_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) {1579  int retval;1580 1581  KMP_DEBUG_ASSERT(gtid >= 0);1582 1583  if (__kmp_get_queuing_lock_owner(lck) == gtid) {1584    retval = ++lck->lk.depth_locked;1585  } else if (!__kmp_test_queuing_lock(lck, gtid)) {1586    retval = 0;1587  } else {1588    KMP_MB();1589    retval = lck->lk.depth_locked = 1;1590    KMP_MB();1591    lck->lk.owner_id = gtid + 1;1592  }1593  return retval;1594}1595 1596static int __kmp_test_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck,1597                                                      kmp_int32 gtid) {1598  char const *const func = "omp_test_nest_lock";1599  if (lck->lk.initialized != lck) {1600    KMP_FATAL(LockIsUninitialized, func);1601  }1602  if (!__kmp_is_queuing_lock_nestable(lck)) {1603    KMP_FATAL(LockSimpleUsedAsNestable, func);1604  }1605  return __kmp_test_nested_queuing_lock(lck, gtid);1606}1607 1608int __kmp_release_nested_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) {1609  KMP_DEBUG_ASSERT(gtid >= 0);1610 1611  KMP_MB();1612  if (--(lck->lk.depth_locked) == 0) {1613    KMP_MB();1614    lck->lk.owner_id = 0;1615    __kmp_release_queuing_lock(lck, gtid);1616    return KMP_LOCK_RELEASED;1617  }1618  return KMP_LOCK_STILL_HELD;1619}1620 1621static int1622__kmp_release_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck,1623                                              kmp_int32 gtid) {1624  char const *const func = "omp_unset_nest_lock";1625  KMP_MB(); /* in case another processor initialized lock */1626  if (lck->lk.initialized != lck) {1627    KMP_FATAL(LockIsUninitialized, func);1628  }1629  if (!__kmp_is_queuing_lock_nestable(lck)) {1630    KMP_FATAL(LockSimpleUsedAsNestable, func);1631  }1632  if (__kmp_get_queuing_lock_owner(lck) == -1) {1633    KMP_FATAL(LockUnsettingFree, func);1634  }1635  if (__kmp_get_queuing_lock_owner(lck) != gtid) {1636    KMP_FATAL(LockUnsettingSetByAnother, func);1637  }1638  return __kmp_release_nested_queuing_lock(lck, gtid);1639}1640 1641void __kmp_init_nested_queuing_lock(kmp_queuing_lock_t *lck) {1642  __kmp_init_queuing_lock(lck);1643  lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks1644}1645 1646void __kmp_destroy_nested_queuing_lock(kmp_queuing_lock_t *lck) {1647  __kmp_destroy_queuing_lock(lck);1648  lck->lk.depth_locked = 0;1649}1650 1651static void1652__kmp_destroy_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck) {1653  char const *const func = "omp_destroy_nest_lock";1654  if (lck->lk.initialized != lck) {1655    KMP_FATAL(LockIsUninitialized, func);1656  }1657  if (!__kmp_is_queuing_lock_nestable(lck)) {1658    KMP_FATAL(LockSimpleUsedAsNestable, func);1659  }1660  if (__kmp_get_queuing_lock_owner(lck) != -1) {1661    KMP_FATAL(LockStillOwned, func);1662  }1663  __kmp_destroy_nested_queuing_lock(lck);1664}1665 1666// access functions to fields which don't exist for all lock kinds.1667 1668static const ident_t *__kmp_get_queuing_lock_location(kmp_queuing_lock_t *lck) {1669  return lck->lk.location;1670}1671 1672static void __kmp_set_queuing_lock_location(kmp_queuing_lock_t *lck,1673                                            const ident_t *loc) {1674  lck->lk.location = loc;1675}1676 1677static kmp_lock_flags_t __kmp_get_queuing_lock_flags(kmp_queuing_lock_t *lck) {1678  return lck->lk.flags;1679}1680 1681static void __kmp_set_queuing_lock_flags(kmp_queuing_lock_t *lck,1682                                         kmp_lock_flags_t flags) {1683  lck->lk.flags = flags;1684}1685 1686#if KMP_USE_ADAPTIVE_LOCKS1687 1688/* RTM Adaptive locks */1689 1690#if KMP_HAVE_RTM_INTRINSICS1691#include <immintrin.h>1692#define SOFT_ABORT_MASK (_XABORT_RETRY | _XABORT_CONFLICT | _XABORT_EXPLICIT)1693 1694#else1695 1696// Values from the status register after failed speculation.1697#define _XBEGIN_STARTED (~0u)1698#define _XABORT_EXPLICIT (1 << 0)1699#define _XABORT_RETRY (1 << 1)1700#define _XABORT_CONFLICT (1 << 2)1701#define _XABORT_CAPACITY (1 << 3)1702#define _XABORT_DEBUG (1 << 4)1703#define _XABORT_NESTED (1 << 5)1704#define _XABORT_CODE(x) ((unsigned char)(((x) >> 24) & 0xFF))1705 1706// Aborts for which it's worth trying again immediately1707#define SOFT_ABORT_MASK (_XABORT_RETRY | _XABORT_CONFLICT | _XABORT_EXPLICIT)1708 1709#define STRINGIZE_INTERNAL(arg) #arg1710#define STRINGIZE(arg) STRINGIZE_INTERNAL(arg)1711 1712// Access to RTM instructions1713/*A version of XBegin which returns -1 on speculation, and the value of EAX on1714  an abort. This is the same definition as the compiler intrinsic that will be1715  supported at some point. */1716static __inline int _xbegin() {1717  int res = -1;1718 1719#if KMP_OS_WINDOWS1720#if KMP_ARCH_X86_641721  _asm {1722        _emit 0xC71723        _emit 0xF81724        _emit 21725        _emit 01726        _emit 01727        _emit 01728        jmp   L21729        mov   res, eax1730    L2:1731  }1732#else /* IA32 */1733  _asm {1734        _emit 0xC71735        _emit 0xF81736        _emit 21737        _emit 01738        _emit 01739        _emit 01740        jmp   L21741        mov   res, eax1742    L2:1743  }1744#endif // KMP_ARCH_X86_641745#else1746  /* Note that %eax must be noted as killed (clobbered), because the XSR is1747     returned in %eax(%rax) on abort.  Other register values are restored, so1748     don't need to be killed.1749 1750     We must also mark 'res' as an input and an output, since otherwise1751     'res=-1' may be dropped as being dead, whereas we do need the assignment on1752     the successful (i.e., non-abort) path. */1753  __asm__ volatile("1: .byte  0xC7; .byte 0xF8;\n"1754                   "   .long  1f-1b-6\n"1755                   "    jmp   2f\n"1756                   "1:  movl  %%eax,%0\n"1757                   "2:"1758                   : "+r"(res)::"memory", "%eax");1759#endif // KMP_OS_WINDOWS1760  return res;1761}1762 1763/* Transaction end */1764static __inline void _xend() {1765#if KMP_OS_WINDOWS1766  __asm {1767        _emit 0x0f1768        _emit 0x011769        _emit 0xd51770  }1771#else1772  __asm__ volatile(".byte 0x0f; .byte 0x01; .byte 0xd5" ::: "memory");1773#endif1774}1775 1776/* This is a macro, the argument must be a single byte constant which can be1777   evaluated by the inline assembler, since it is emitted as a byte into the1778   assembly code. */1779// clang-format off1780#if KMP_OS_WINDOWS1781#define _xabort(ARG) _asm _emit 0xc6 _asm _emit 0xf8 _asm _emit ARG1782#else1783#define _xabort(ARG)                                                           \1784  __asm__ volatile(".byte 0xC6; .byte 0xF8; .byte " STRINGIZE(ARG):::"memory");1785#endif1786// clang-format on1787#endif // KMP_COMPILER_ICC && __INTEL_COMPILER >= 13001788 1789// Statistics is collected for testing purpose1790#if KMP_DEBUG_ADAPTIVE_LOCKS1791 1792// We accumulate speculative lock statistics when the lock is destroyed. We1793// keep locks that haven't been destroyed in the liveLocks list so that we can1794// grab their statistics too.1795static kmp_adaptive_lock_statistics_t destroyedStats;1796 1797// To hold the list of live locks.1798static kmp_adaptive_lock_info_t liveLocks;1799 1800// A lock so we can safely update the list of locks.1801static kmp_bootstrap_lock_t chain_lock =1802    KMP_BOOTSTRAP_LOCK_INITIALIZER(chain_lock);1803 1804// Initialize the list of stats.1805void __kmp_init_speculative_stats() {1806  kmp_adaptive_lock_info_t *lck = &liveLocks;1807 1808  memset(CCAST(kmp_adaptive_lock_statistics_t *, &(lck->stats)), 0,1809         sizeof(lck->stats));1810  lck->stats.next = lck;1811  lck->stats.prev = lck;1812 1813  KMP_ASSERT(lck->stats.next->stats.prev == lck);1814  KMP_ASSERT(lck->stats.prev->stats.next == lck);1815 1816  __kmp_init_bootstrap_lock(&chain_lock);1817}1818 1819// Insert the lock into the circular list1820static void __kmp_remember_lock(kmp_adaptive_lock_info_t *lck) {1821  __kmp_acquire_bootstrap_lock(&chain_lock);1822 1823  lck->stats.next = liveLocks.stats.next;1824  lck->stats.prev = &liveLocks;1825 1826  liveLocks.stats.next = lck;1827  lck->stats.next->stats.prev = lck;1828 1829  KMP_ASSERT(lck->stats.next->stats.prev == lck);1830  KMP_ASSERT(lck->stats.prev->stats.next == lck);1831 1832  __kmp_release_bootstrap_lock(&chain_lock);1833}1834 1835static void __kmp_forget_lock(kmp_adaptive_lock_info_t *lck) {1836  KMP_ASSERT(lck->stats.next->stats.prev == lck);1837  KMP_ASSERT(lck->stats.prev->stats.next == lck);1838 1839  kmp_adaptive_lock_info_t *n = lck->stats.next;1840  kmp_adaptive_lock_info_t *p = lck->stats.prev;1841 1842  n->stats.prev = p;1843  p->stats.next = n;1844}1845 1846static void __kmp_zero_speculative_stats(kmp_adaptive_lock_info_t *lck) {1847  memset(CCAST(kmp_adaptive_lock_statistics_t *, &lck->stats), 0,1848         sizeof(lck->stats));1849  __kmp_remember_lock(lck);1850}1851 1852static void __kmp_add_stats(kmp_adaptive_lock_statistics_t *t,1853                            kmp_adaptive_lock_info_t *lck) {1854  kmp_adaptive_lock_statistics_t volatile *s = &lck->stats;1855 1856  t->nonSpeculativeAcquireAttempts += lck->acquire_attempts;1857  t->successfulSpeculations += s->successfulSpeculations;1858  t->hardFailedSpeculations += s->hardFailedSpeculations;1859  t->softFailedSpeculations += s->softFailedSpeculations;1860  t->nonSpeculativeAcquires += s->nonSpeculativeAcquires;1861  t->lemmingYields += s->lemmingYields;1862}1863 1864static void __kmp_accumulate_speculative_stats(kmp_adaptive_lock_info_t *lck) {1865  __kmp_acquire_bootstrap_lock(&chain_lock);1866 1867  __kmp_add_stats(&destroyedStats, lck);1868  __kmp_forget_lock(lck);1869 1870  __kmp_release_bootstrap_lock(&chain_lock);1871}1872 1873static float percent(kmp_uint32 count, kmp_uint32 total) {1874  return (total == 0) ? 0.0 : (100.0 * count) / total;1875}1876 1877void __kmp_print_speculative_stats() {1878  kmp_adaptive_lock_statistics_t total = destroyedStats;1879  kmp_adaptive_lock_info_t *lck;1880 1881  for (lck = liveLocks.stats.next; lck != &liveLocks; lck = lck->stats.next) {1882    __kmp_add_stats(&total, lck);1883  }1884  kmp_adaptive_lock_statistics_t *t = &total;1885  kmp_uint32 totalSections =1886      t->nonSpeculativeAcquires + t->successfulSpeculations;1887  kmp_uint32 totalSpeculations = t->successfulSpeculations +1888                                 t->hardFailedSpeculations +1889                                 t->softFailedSpeculations;1890  if (totalSections <= 0)1891    return;1892 1893  kmp_safe_raii_file_t statsFile;1894  if (strcmp(__kmp_speculative_statsfile, "-") == 0) {1895    statsFile.set_stdout();1896  } else {1897    size_t buffLen = KMP_STRLEN(__kmp_speculative_statsfile) + 20;1898    char buffer[buffLen];1899    KMP_SNPRINTF(&buffer[0], buffLen, __kmp_speculative_statsfile,1900                 (kmp_int32)getpid());1901    statsFile.open(buffer, "w");1902  }1903 1904  fprintf(statsFile, "Speculative lock statistics (all approximate!)\n");1905  fprintf(statsFile,1906          " Lock parameters: \n"1907          "   max_soft_retries               : %10d\n"1908          "   max_badness                    : %10d\n",1909          __kmp_adaptive_backoff_params.max_soft_retries,1910          __kmp_adaptive_backoff_params.max_badness);1911  fprintf(statsFile, " Non-speculative acquire attempts : %10d\n",1912          t->nonSpeculativeAcquireAttempts);1913  fprintf(statsFile, " Total critical sections          : %10d\n",1914          totalSections);1915  fprintf(statsFile, " Successful speculations          : %10d (%5.1f%%)\n",1916          t->successfulSpeculations,1917          percent(t->successfulSpeculations, totalSections));1918  fprintf(statsFile, " Non-speculative acquires         : %10d (%5.1f%%)\n",1919          t->nonSpeculativeAcquires,1920          percent(t->nonSpeculativeAcquires, totalSections));1921  fprintf(statsFile, " Lemming yields                   : %10d\n\n",1922          t->lemmingYields);1923 1924  fprintf(statsFile, " Speculative acquire attempts     : %10d\n",1925          totalSpeculations);1926  fprintf(statsFile, " Successes                        : %10d (%5.1f%%)\n",1927          t->successfulSpeculations,1928          percent(t->successfulSpeculations, totalSpeculations));1929  fprintf(statsFile, " Soft failures                    : %10d (%5.1f%%)\n",1930          t->softFailedSpeculations,1931          percent(t->softFailedSpeculations, totalSpeculations));1932  fprintf(statsFile, " Hard failures                    : %10d (%5.1f%%)\n",1933          t->hardFailedSpeculations,1934          percent(t->hardFailedSpeculations, totalSpeculations));1935}1936 1937#define KMP_INC_STAT(lck, stat) (lck->lk.adaptive.stats.stat++)1938#else1939#define KMP_INC_STAT(lck, stat)1940 1941#endif // KMP_DEBUG_ADAPTIVE_LOCKS1942 1943static inline bool __kmp_is_unlocked_queuing_lock(kmp_queuing_lock_t *lck) {1944  // It is enough to check that the head_id is zero.1945  // We don't also need to check the tail.1946  bool res = lck->lk.head_id == 0;1947 1948// We need a fence here, since we must ensure that no memory operations1949// from later in this thread float above that read.1950#if KMP_COMPILER_ICC || KMP_COMPILER_ICX1951  _mm_mfence();1952#else1953  __sync_synchronize();1954#endif1955 1956  return res;1957}1958 1959// Functions for manipulating the badness1960static __inline void1961__kmp_update_badness_after_success(kmp_adaptive_lock_t *lck) {1962  // Reset the badness to zero so we eagerly try to speculate again1963  lck->lk.adaptive.badness = 0;1964  KMP_INC_STAT(lck, successfulSpeculations);1965}1966 1967// Create a bit mask with one more set bit.1968static __inline void __kmp_step_badness(kmp_adaptive_lock_t *lck) {1969  kmp_uint32 newBadness = (lck->lk.adaptive.badness << 1) | 1;1970  if (newBadness > lck->lk.adaptive.max_badness) {1971    return;1972  } else {1973    lck->lk.adaptive.badness = newBadness;1974  }1975}1976 1977// Check whether speculation should be attempted.1978KMP_ATTRIBUTE_TARGET_RTM1979static __inline int __kmp_should_speculate(kmp_adaptive_lock_t *lck,1980                                           kmp_int32 gtid) {1981  kmp_uint32 badness = lck->lk.adaptive.badness;1982  kmp_uint32 attempts = lck->lk.adaptive.acquire_attempts;1983  int res = (attempts & badness) == 0;1984  return res;1985}1986 1987// Attempt to acquire only the speculative lock.1988// Does not back off to the non-speculative lock.1989KMP_ATTRIBUTE_TARGET_RTM1990static int __kmp_test_adaptive_lock_only(kmp_adaptive_lock_t *lck,1991                                         kmp_int32 gtid) {1992  int retries = lck->lk.adaptive.max_soft_retries;1993 1994  // We don't explicitly count the start of speculation, rather we record the1995  // results (success, hard fail, soft fail). The sum of all of those is the1996  // total number of times we started speculation since all speculations must1997  // end one of those ways.1998  do {1999    kmp_uint32 status = _xbegin();2000    // Switch this in to disable actual speculation but exercise at least some2001    // of the rest of the code. Useful for debugging...2002    // kmp_uint32 status = _XABORT_NESTED;2003 2004    if (status == _XBEGIN_STARTED) {2005      /* We have successfully started speculation. Check that no-one acquired2006         the lock for real between when we last looked and now. This also gets2007         the lock cache line into our read-set, which we need so that we'll2008         abort if anyone later claims it for real. */2009      if (!__kmp_is_unlocked_queuing_lock(GET_QLK_PTR(lck))) {2010        // Lock is now visibly acquired, so someone beat us to it. Abort the2011        // transaction so we'll restart from _xbegin with the failure status.2012        _xabort(0x01);2013        KMP_ASSERT2(0, "should not get here");2014      }2015      return 1; // Lock has been acquired (speculatively)2016    } else {2017      // We have aborted, update the statistics2018      if (status & SOFT_ABORT_MASK) {2019        KMP_INC_STAT(lck, softFailedSpeculations);2020        // and loop round to retry.2021      } else {2022        KMP_INC_STAT(lck, hardFailedSpeculations);2023        // Give up if we had a hard failure.2024        break;2025      }2026    }2027  } while (retries--); // Loop while we have retries, and didn't fail hard.2028 2029  // Either we had a hard failure or we didn't succeed softly after2030  // the full set of attempts, so back off the badness.2031  __kmp_step_badness(lck);2032  return 0;2033}2034 2035// Attempt to acquire the speculative lock, or back off to the non-speculative2036// one if the speculative lock cannot be acquired.2037// We can succeed speculatively, non-speculatively, or fail.2038static int __kmp_test_adaptive_lock(kmp_adaptive_lock_t *lck, kmp_int32 gtid) {2039  // First try to acquire the lock speculatively2040  if (__kmp_should_speculate(lck, gtid) &&2041      __kmp_test_adaptive_lock_only(lck, gtid))2042    return 1;2043 2044  // Speculative acquisition failed, so try to acquire it non-speculatively.2045  // Count the non-speculative acquire attempt2046  lck->lk.adaptive.acquire_attempts++;2047 2048  // Use base, non-speculative lock.2049  if (__kmp_test_queuing_lock(GET_QLK_PTR(lck), gtid)) {2050    KMP_INC_STAT(lck, nonSpeculativeAcquires);2051    return 1; // Lock is acquired (non-speculatively)2052  } else {2053    return 0; // Failed to acquire the lock, it's already visibly locked.2054  }2055}2056 2057static int __kmp_test_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck,2058                                                kmp_int32 gtid) {2059  char const *const func = "omp_test_lock";2060  if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) {2061    KMP_FATAL(LockIsUninitialized, func);2062  }2063 2064  int retval = __kmp_test_adaptive_lock(lck, gtid);2065 2066  if (retval) {2067    lck->lk.qlk.owner_id = gtid + 1;2068  }2069  return retval;2070}2071 2072// Block until we can acquire a speculative, adaptive lock. We check whether we2073// should be trying to speculate. If we should be, we check the real lock to see2074// if it is free, and, if not, pause without attempting to acquire it until it2075// is. Then we try the speculative acquire. This means that although we suffer2076// from lemmings a little (because all we can't acquire the lock speculatively2077// until the queue of threads waiting has cleared), we don't get into a state2078// where we can never acquire the lock speculatively (because we force the queue2079// to clear by preventing new arrivals from entering the queue). This does mean2080// that when we're trying to break lemmings, the lock is no longer fair. However2081// OpenMP makes no guarantee that its locks are fair, so this isn't a real2082// problem.2083static void __kmp_acquire_adaptive_lock(kmp_adaptive_lock_t *lck,2084                                        kmp_int32 gtid) {2085  if (__kmp_should_speculate(lck, gtid)) {2086    if (__kmp_is_unlocked_queuing_lock(GET_QLK_PTR(lck))) {2087      if (__kmp_test_adaptive_lock_only(lck, gtid))2088        return;2089      // We tried speculation and failed, so give up.2090    } else {2091      // We can't try speculation until the lock is free, so we pause here2092      // (without suspending on the queueing lock, to allow it to drain, then2093      // try again. All other threads will also see the same result for2094      // shouldSpeculate, so will be doing the same if they try to claim the2095      // lock from now on.2096      while (!__kmp_is_unlocked_queuing_lock(GET_QLK_PTR(lck))) {2097        KMP_INC_STAT(lck, lemmingYields);2098        KMP_YIELD(TRUE);2099      }2100 2101      if (__kmp_test_adaptive_lock_only(lck, gtid))2102        return;2103    }2104  }2105 2106  // Speculative acquisition failed, so acquire it non-speculatively.2107  // Count the non-speculative acquire attempt2108  lck->lk.adaptive.acquire_attempts++;2109 2110  __kmp_acquire_queuing_lock_timed_template<FALSE>(GET_QLK_PTR(lck), gtid);2111  // We have acquired the base lock, so count that.2112  KMP_INC_STAT(lck, nonSpeculativeAcquires);2113}2114 2115static void __kmp_acquire_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck,2116                                                    kmp_int32 gtid) {2117  char const *const func = "omp_set_lock";2118  if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) {2119    KMP_FATAL(LockIsUninitialized, func);2120  }2121  if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) == gtid) {2122    KMP_FATAL(LockIsAlreadyOwned, func);2123  }2124 2125  __kmp_acquire_adaptive_lock(lck, gtid);2126 2127  lck->lk.qlk.owner_id = gtid + 1;2128}2129 2130KMP_ATTRIBUTE_TARGET_RTM2131static int __kmp_release_adaptive_lock(kmp_adaptive_lock_t *lck,2132                                       kmp_int32 gtid) {2133  if (__kmp_is_unlocked_queuing_lock(GET_QLK_PTR(2134          lck))) { // If the lock doesn't look claimed we must be speculating.2135    // (Or the user's code is buggy and they're releasing without locking;2136    // if we had XTEST we'd be able to check that case...)2137    _xend(); // Exit speculation2138    __kmp_update_badness_after_success(lck);2139  } else { // Since the lock *is* visibly locked we're not speculating,2140    // so should use the underlying lock's release scheme.2141    __kmp_release_queuing_lock(GET_QLK_PTR(lck), gtid);2142  }2143  return KMP_LOCK_RELEASED;2144}2145 2146static int __kmp_release_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck,2147                                                   kmp_int32 gtid) {2148  char const *const func = "omp_unset_lock";2149  KMP_MB(); /* in case another processor initialized lock */2150  if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) {2151    KMP_FATAL(LockIsUninitialized, func);2152  }2153  if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) == -1) {2154    KMP_FATAL(LockUnsettingFree, func);2155  }2156  if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) != gtid) {2157    KMP_FATAL(LockUnsettingSetByAnother, func);2158  }2159  lck->lk.qlk.owner_id = 0;2160  __kmp_release_adaptive_lock(lck, gtid);2161  return KMP_LOCK_RELEASED;2162}2163 2164static void __kmp_init_adaptive_lock(kmp_adaptive_lock_t *lck) {2165  __kmp_init_queuing_lock(GET_QLK_PTR(lck));2166  lck->lk.adaptive.badness = 0;2167  lck->lk.adaptive.acquire_attempts = 0; // nonSpeculativeAcquireAttempts = 0;2168  lck->lk.adaptive.max_soft_retries =2169      __kmp_adaptive_backoff_params.max_soft_retries;2170  lck->lk.adaptive.max_badness = __kmp_adaptive_backoff_params.max_badness;2171#if KMP_DEBUG_ADAPTIVE_LOCKS2172  __kmp_zero_speculative_stats(&lck->lk.adaptive);2173#endif2174  KA_TRACE(1000, ("__kmp_init_adaptive_lock: lock %p initialized\n", lck));2175}2176 2177static void __kmp_destroy_adaptive_lock(kmp_adaptive_lock_t *lck) {2178#if KMP_DEBUG_ADAPTIVE_LOCKS2179  __kmp_accumulate_speculative_stats(&lck->lk.adaptive);2180#endif2181  __kmp_destroy_queuing_lock(GET_QLK_PTR(lck));2182  // Nothing needed for the speculative part.2183}2184 2185static void __kmp_destroy_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck) {2186  char const *const func = "omp_destroy_lock";2187  if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) {2188    KMP_FATAL(LockIsUninitialized, func);2189  }2190  if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) != -1) {2191    KMP_FATAL(LockStillOwned, func);2192  }2193  __kmp_destroy_adaptive_lock(lck);2194}2195 2196#endif // KMP_USE_ADAPTIVE_LOCKS2197 2198/* ------------------------------------------------------------------------ */2199/* DRDPA ticket locks                                                */2200/* "DRDPA" means Dynamically Reconfigurable Distributed Polling Area */2201 2202static kmp_int32 __kmp_get_drdpa_lock_owner(kmp_drdpa_lock_t *lck) {2203  return lck->lk.owner_id - 1;2204}2205 2206static inline bool __kmp_is_drdpa_lock_nestable(kmp_drdpa_lock_t *lck) {2207  return lck->lk.depth_locked != -1;2208}2209 2210__forceinline static int2211__kmp_acquire_drdpa_lock_timed_template(kmp_drdpa_lock_t *lck, kmp_int32 gtid) {2212  kmp_uint64 ticket = KMP_ATOMIC_INC(&lck->lk.next_ticket);2213  kmp_uint64 mask = lck->lk.mask; // atomic load2214  std::atomic<kmp_uint64> *polls = lck->lk.polls;2215 2216#ifdef USE_LOCK_PROFILE2217  if (polls[ticket & mask] != ticket)2218    __kmp_printf("LOCK CONTENTION: %p\n", lck);2219/* else __kmp_printf( "." );*/2220#endif /* USE_LOCK_PROFILE */2221 2222  // Now spin-wait, but reload the polls pointer and mask, in case the2223  // polling area has been reconfigured.  Unless it is reconfigured, the2224  // reloads stay in L1 cache and are cheap.2225  //2226  // Keep this code in sync with KMP_WAIT, in kmp_dispatch.cpp !!!2227  // The current implementation of KMP_WAIT doesn't allow for mask2228  // and poll to be re-read every spin iteration.2229  kmp_uint32 spins;2230  kmp_uint64 time;2231  KMP_FSYNC_PREPARE(lck);2232  KMP_INIT_YIELD(spins);2233  KMP_INIT_BACKOFF(time);2234  while (polls[ticket & mask] < ticket) { // atomic load2235    KMP_YIELD_OVERSUB_ELSE_SPIN(spins, time);2236    // Re-read the mask and the poll pointer from the lock structure.2237    //2238    // Make certain that "mask" is read before "polls" !!!2239    //2240    // If another thread picks reconfigures the polling area and updates their2241    // values, and we get the new value of mask and the old polls pointer, we2242    // could access memory beyond the end of the old polling area.2243    mask = lck->lk.mask; // atomic load2244    polls = lck->lk.polls; // atomic load2245  }2246 2247  // Critical section starts here2248  KMP_FSYNC_ACQUIRED(lck);2249  KA_TRACE(1000, ("__kmp_acquire_drdpa_lock: ticket #%lld acquired lock %p\n",2250                  ticket, lck));2251  lck->lk.now_serving = ticket; // non-volatile store2252 2253  // Deallocate a garbage polling area if we know that we are the last2254  // thread that could possibly access it.2255  //2256  // The >= check is in case __kmp_test_drdpa_lock() allocated the cleanup2257  // ticket.2258  if ((lck->lk.old_polls != NULL) && (ticket >= lck->lk.cleanup_ticket)) {2259    __kmp_free(lck->lk.old_polls);2260    lck->lk.old_polls = NULL;2261    lck->lk.cleanup_ticket = 0;2262  }2263 2264  // Check to see if we should reconfigure the polling area.2265  // If there is still a garbage polling area to be deallocated from a2266  // previous reconfiguration, let a later thread reconfigure it.2267  if (lck->lk.old_polls == NULL) {2268    bool reconfigure = false;2269    std::atomic<kmp_uint64> *old_polls = polls;2270    kmp_uint32 num_polls = TCR_4(lck->lk.num_polls);2271 2272    if (TCR_4(__kmp_nth) >2273        (__kmp_avail_proc ? __kmp_avail_proc : __kmp_xproc)) {2274      // We are in oversubscription mode.  Contract the polling area2275      // down to a single location, if that hasn't been done already.2276      if (num_polls > 1) {2277        reconfigure = true;2278        num_polls = TCR_4(lck->lk.num_polls);2279        mask = 0;2280        num_polls = 1;2281        polls = (std::atomic<kmp_uint64> *)__kmp_allocate(num_polls *2282                                                          sizeof(*polls));2283        polls[0] = ticket;2284      }2285    } else {2286      // We are in under/fully subscribed mode.  Check the number of2287      // threads waiting on the lock.  The size of the polling area2288      // should be at least the number of threads waiting.2289      kmp_uint64 num_waiting = TCR_8(lck->lk.next_ticket) - ticket - 1;2290      if (num_waiting > num_polls) {2291        kmp_uint32 old_num_polls = num_polls;2292        reconfigure = true;2293        do {2294          mask = (mask << 1) | 1;2295          num_polls *= 2;2296        } while (num_polls <= num_waiting);2297 2298        // Allocate the new polling area, and copy the relevant portion2299        // of the old polling area to the new area.  __kmp_allocate()2300        // zeroes the memory it allocates, and most of the old area is2301        // just zero padding, so we only copy the release counters.2302        polls = (std::atomic<kmp_uint64> *)__kmp_allocate(num_polls *2303                                                          sizeof(*polls));2304        kmp_uint32 i;2305        for (i = 0; i < old_num_polls; i++) {2306          polls[i].store(old_polls[i]);2307        }2308      }2309    }2310 2311    if (reconfigure) {2312      // Now write the updated fields back to the lock structure.2313      //2314      // Make certain that "polls" is written before "mask" !!!2315      //2316      // If another thread picks up the new value of mask and the old polls2317      // pointer , it could access memory beyond the end of the old polling2318      // area.2319      //2320      // On x86, we need memory fences.2321      KA_TRACE(1000, ("__kmp_acquire_drdpa_lock: ticket #%lld reconfiguring "2322                      "lock %p to %d polls\n",2323                      ticket, lck, num_polls));2324 2325      lck->lk.old_polls = old_polls;2326      lck->lk.polls = polls; // atomic store2327 2328      KMP_MB();2329 2330      lck->lk.num_polls = num_polls;2331      lck->lk.mask = mask; // atomic store2332 2333      KMP_MB();2334 2335      // Only after the new polling area and mask have been flushed2336      // to main memory can we update the cleanup ticket field.2337      //2338      // volatile load / non-volatile store2339      lck->lk.cleanup_ticket = lck->lk.next_ticket;2340    }2341  }2342  return KMP_LOCK_ACQUIRED_FIRST;2343}2344 2345int __kmp_acquire_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) {2346  int retval = __kmp_acquire_drdpa_lock_timed_template(lck, gtid);2347  return retval;2348}2349 2350static int __kmp_acquire_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck,2351                                                kmp_int32 gtid) {2352  char const *const func = "omp_set_lock";2353  if (lck->lk.initialized != lck) {2354    KMP_FATAL(LockIsUninitialized, func);2355  }2356  if (__kmp_is_drdpa_lock_nestable(lck)) {2357    KMP_FATAL(LockNestableUsedAsSimple, func);2358  }2359  if ((gtid >= 0) && (__kmp_get_drdpa_lock_owner(lck) == gtid)) {2360    KMP_FATAL(LockIsAlreadyOwned, func);2361  }2362 2363  __kmp_acquire_drdpa_lock(lck, gtid);2364 2365  lck->lk.owner_id = gtid + 1;2366  return KMP_LOCK_ACQUIRED_FIRST;2367}2368 2369int __kmp_test_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) {2370  // First get a ticket, then read the polls pointer and the mask.2371  // The polls pointer must be read before the mask!!! (See above)2372  kmp_uint64 ticket = lck->lk.next_ticket; // atomic load2373  std::atomic<kmp_uint64> *polls = lck->lk.polls;2374  kmp_uint64 mask = lck->lk.mask; // atomic load2375  if (polls[ticket & mask] == ticket) {2376    kmp_uint64 next_ticket = ticket + 1;2377    if (__kmp_atomic_compare_store_acq(&lck->lk.next_ticket, ticket,2378                                       next_ticket)) {2379      KMP_FSYNC_ACQUIRED(lck);2380      KA_TRACE(1000, ("__kmp_test_drdpa_lock: ticket #%lld acquired lock %p\n",2381                      ticket, lck));2382      lck->lk.now_serving = ticket; // non-volatile store2383 2384      // Since no threads are waiting, there is no possibility that we would2385      // want to reconfigure the polling area.  We might have the cleanup ticket2386      // value (which says that it is now safe to deallocate old_polls), but2387      // we'll let a later thread which calls __kmp_acquire_lock do that - this2388      // routine isn't supposed to block, and we would risk blocks if we called2389      // __kmp_free() to do the deallocation.2390      return TRUE;2391    }2392  }2393  return FALSE;2394}2395 2396static int __kmp_test_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck,2397                                             kmp_int32 gtid) {2398  char const *const func = "omp_test_lock";2399  if (lck->lk.initialized != lck) {2400    KMP_FATAL(LockIsUninitialized, func);2401  }2402  if (__kmp_is_drdpa_lock_nestable(lck)) {2403    KMP_FATAL(LockNestableUsedAsSimple, func);2404  }2405 2406  int retval = __kmp_test_drdpa_lock(lck, gtid);2407 2408  if (retval) {2409    lck->lk.owner_id = gtid + 1;2410  }2411  return retval;2412}2413 2414int __kmp_release_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) {2415  // Read the ticket value from the lock data struct, then the polls pointer and2416  // the mask.  The polls pointer must be read before the mask!!! (See above)2417  kmp_uint64 ticket = lck->lk.now_serving + 1; // non-atomic load2418  std::atomic<kmp_uint64> *polls = lck->lk.polls; // atomic load2419  kmp_uint64 mask = lck->lk.mask; // atomic load2420  KA_TRACE(1000, ("__kmp_release_drdpa_lock: ticket #%lld released lock %p\n",2421                  ticket - 1, lck));2422  KMP_FSYNC_RELEASING(lck);2423  polls[ticket & mask] = ticket; // atomic store2424  return KMP_LOCK_RELEASED;2425}2426 2427static int __kmp_release_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck,2428                                                kmp_int32 gtid) {2429  char const *const func = "omp_unset_lock";2430  KMP_MB(); /* in case another processor initialized lock */2431  if (lck->lk.initialized != lck) {2432    KMP_FATAL(LockIsUninitialized, func);2433  }2434  if (__kmp_is_drdpa_lock_nestable(lck)) {2435    KMP_FATAL(LockNestableUsedAsSimple, func);2436  }2437  if (__kmp_get_drdpa_lock_owner(lck) == -1) {2438    KMP_FATAL(LockUnsettingFree, func);2439  }2440  if ((gtid >= 0) && (__kmp_get_drdpa_lock_owner(lck) >= 0) &&2441      (__kmp_get_drdpa_lock_owner(lck) != gtid)) {2442    KMP_FATAL(LockUnsettingSetByAnother, func);2443  }2444  lck->lk.owner_id = 0;2445  return __kmp_release_drdpa_lock(lck, gtid);2446}2447 2448void __kmp_init_drdpa_lock(kmp_drdpa_lock_t *lck) {2449  lck->lk.location = NULL;2450  lck->lk.mask = 0;2451  lck->lk.num_polls = 1;2452  lck->lk.polls = (std::atomic<kmp_uint64> *)__kmp_allocate(2453      lck->lk.num_polls * sizeof(*(lck->lk.polls)));2454  lck->lk.cleanup_ticket = 0;2455  lck->lk.old_polls = NULL;2456  lck->lk.next_ticket = 0;2457  lck->lk.now_serving = 0;2458  lck->lk.owner_id = 0; // no thread owns the lock.2459  lck->lk.depth_locked = -1; // >= 0 for nestable locks, -1 for simple locks.2460  lck->lk.initialized = lck;2461 2462  KA_TRACE(1000, ("__kmp_init_drdpa_lock: lock %p initialized\n", lck));2463}2464 2465void __kmp_destroy_drdpa_lock(kmp_drdpa_lock_t *lck) {2466  lck->lk.initialized = NULL;2467  lck->lk.location = NULL;2468  if (lck->lk.polls.load() != NULL) {2469    __kmp_free(lck->lk.polls.load());2470    lck->lk.polls = NULL;2471  }2472  if (lck->lk.old_polls != NULL) {2473    __kmp_free(lck->lk.old_polls);2474    lck->lk.old_polls = NULL;2475  }2476  lck->lk.mask = 0;2477  lck->lk.num_polls = 0;2478  lck->lk.cleanup_ticket = 0;2479  lck->lk.next_ticket = 0;2480  lck->lk.now_serving = 0;2481  lck->lk.owner_id = 0;2482  lck->lk.depth_locked = -1;2483}2484 2485static void __kmp_destroy_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) {2486  char const *const func = "omp_destroy_lock";2487  if (lck->lk.initialized != lck) {2488    KMP_FATAL(LockIsUninitialized, func);2489  }2490  if (__kmp_is_drdpa_lock_nestable(lck)) {2491    KMP_FATAL(LockNestableUsedAsSimple, func);2492  }2493  if (__kmp_get_drdpa_lock_owner(lck) != -1) {2494    KMP_FATAL(LockStillOwned, func);2495  }2496  __kmp_destroy_drdpa_lock(lck);2497}2498 2499// nested drdpa ticket locks2500 2501int __kmp_acquire_nested_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) {2502  KMP_DEBUG_ASSERT(gtid >= 0);2503 2504  if (__kmp_get_drdpa_lock_owner(lck) == gtid) {2505    lck->lk.depth_locked += 1;2506    return KMP_LOCK_ACQUIRED_NEXT;2507  } else {2508    __kmp_acquire_drdpa_lock_timed_template(lck, gtid);2509    KMP_MB();2510    lck->lk.depth_locked = 1;2511    KMP_MB();2512    lck->lk.owner_id = gtid + 1;2513    return KMP_LOCK_ACQUIRED_FIRST;2514  }2515}2516 2517static void __kmp_acquire_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck,2518                                                        kmp_int32 gtid) {2519  char const *const func = "omp_set_nest_lock";2520  if (lck->lk.initialized != lck) {2521    KMP_FATAL(LockIsUninitialized, func);2522  }2523  if (!__kmp_is_drdpa_lock_nestable(lck)) {2524    KMP_FATAL(LockSimpleUsedAsNestable, func);2525  }2526  __kmp_acquire_nested_drdpa_lock(lck, gtid);2527}2528 2529int __kmp_test_nested_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) {2530  int retval;2531 2532  KMP_DEBUG_ASSERT(gtid >= 0);2533 2534  if (__kmp_get_drdpa_lock_owner(lck) == gtid) {2535    retval = ++lck->lk.depth_locked;2536  } else if (!__kmp_test_drdpa_lock(lck, gtid)) {2537    retval = 0;2538  } else {2539    KMP_MB();2540    retval = lck->lk.depth_locked = 1;2541    KMP_MB();2542    lck->lk.owner_id = gtid + 1;2543  }2544  return retval;2545}2546 2547static int __kmp_test_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck,2548                                                    kmp_int32 gtid) {2549  char const *const func = "omp_test_nest_lock";2550  if (lck->lk.initialized != lck) {2551    KMP_FATAL(LockIsUninitialized, func);2552  }2553  if (!__kmp_is_drdpa_lock_nestable(lck)) {2554    KMP_FATAL(LockSimpleUsedAsNestable, func);2555  }2556  return __kmp_test_nested_drdpa_lock(lck, gtid);2557}2558 2559int __kmp_release_nested_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) {2560  KMP_DEBUG_ASSERT(gtid >= 0);2561 2562  KMP_MB();2563  if (--(lck->lk.depth_locked) == 0) {2564    KMP_MB();2565    lck->lk.owner_id = 0;2566    __kmp_release_drdpa_lock(lck, gtid);2567    return KMP_LOCK_RELEASED;2568  }2569  return KMP_LOCK_STILL_HELD;2570}2571 2572static int __kmp_release_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck,2573                                                       kmp_int32 gtid) {2574  char const *const func = "omp_unset_nest_lock";2575  KMP_MB(); /* in case another processor initialized lock */2576  if (lck->lk.initialized != lck) {2577    KMP_FATAL(LockIsUninitialized, func);2578  }2579  if (!__kmp_is_drdpa_lock_nestable(lck)) {2580    KMP_FATAL(LockSimpleUsedAsNestable, func);2581  }2582  if (__kmp_get_drdpa_lock_owner(lck) == -1) {2583    KMP_FATAL(LockUnsettingFree, func);2584  }2585  if (__kmp_get_drdpa_lock_owner(lck) != gtid) {2586    KMP_FATAL(LockUnsettingSetByAnother, func);2587  }2588  return __kmp_release_nested_drdpa_lock(lck, gtid);2589}2590 2591void __kmp_init_nested_drdpa_lock(kmp_drdpa_lock_t *lck) {2592  __kmp_init_drdpa_lock(lck);2593  lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks2594}2595 2596void __kmp_destroy_nested_drdpa_lock(kmp_drdpa_lock_t *lck) {2597  __kmp_destroy_drdpa_lock(lck);2598  lck->lk.depth_locked = 0;2599}2600 2601static void __kmp_destroy_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) {2602  char const *const func = "omp_destroy_nest_lock";2603  if (lck->lk.initialized != lck) {2604    KMP_FATAL(LockIsUninitialized, func);2605  }2606  if (!__kmp_is_drdpa_lock_nestable(lck)) {2607    KMP_FATAL(LockSimpleUsedAsNestable, func);2608  }2609  if (__kmp_get_drdpa_lock_owner(lck) != -1) {2610    KMP_FATAL(LockStillOwned, func);2611  }2612  __kmp_destroy_nested_drdpa_lock(lck);2613}2614 2615// access functions to fields which don't exist for all lock kinds.2616 2617static const ident_t *__kmp_get_drdpa_lock_location(kmp_drdpa_lock_t *lck) {2618  return lck->lk.location;2619}2620 2621static void __kmp_set_drdpa_lock_location(kmp_drdpa_lock_t *lck,2622                                          const ident_t *loc) {2623  lck->lk.location = loc;2624}2625 2626static kmp_lock_flags_t __kmp_get_drdpa_lock_flags(kmp_drdpa_lock_t *lck) {2627  return lck->lk.flags;2628}2629 2630static void __kmp_set_drdpa_lock_flags(kmp_drdpa_lock_t *lck,2631                                       kmp_lock_flags_t flags) {2632  lck->lk.flags = flags;2633}2634 2635// Time stamp counter2636#if KMP_ARCH_X86 || KMP_ARCH_X86_642637#define __kmp_tsc() __kmp_hardware_timestamp()2638// Runtime's default backoff parameters2639kmp_backoff_t __kmp_spin_backoff_params = {1, 4096, 100};2640#else2641// Use nanoseconds for other platforms2642extern kmp_uint64 __kmp_now_nsec();2643kmp_backoff_t __kmp_spin_backoff_params = {1, 256, 100};2644#define __kmp_tsc() __kmp_now_nsec()2645#endif2646 2647// A useful predicate for dealing with timestamps that may wrap.2648// Is a before b? Since the timestamps may wrap, this is asking whether it's2649// shorter to go clockwise from a to b around the clock-face, or anti-clockwise.2650// Times where going clockwise is less distance than going anti-clockwise2651// are in the future, others are in the past. e.g. a = MAX-1, b = MAX+1 (=0),2652// then a > b (true) does not mean a reached b; whereas signed(a) = -2,2653// signed(b) = 0 captures the actual difference2654static inline bool before(kmp_uint64 a, kmp_uint64 b) {2655  return ((kmp_int64)b - (kmp_int64)a) > 0;2656}2657 2658// Truncated binary exponential backoff function2659void __kmp_spin_backoff(kmp_backoff_t *boff) {2660  // We could flatten this loop, but making it a nested loop gives better result2661  kmp_uint32 i;2662  for (i = boff->step; i > 0; i--) {2663    kmp_uint64 goal = __kmp_tsc() + boff->min_tick;2664#if KMP_HAVE_UMWAIT2665    if (__kmp_umwait_enabled) {2666      __kmp_tpause(0, boff->min_tick);2667    } else {2668#endif2669      do {2670        KMP_CPU_PAUSE();2671      } while (before(__kmp_tsc(), goal));2672#if KMP_HAVE_UMWAIT2673    }2674#endif2675  }2676  boff->step = (boff->step << 1 | 1) & (boff->max_backoff - 1);2677}2678 2679#if KMP_USE_DYNAMIC_LOCK2680 2681// Direct lock initializers. It simply writes a tag to the low 8 bits of the2682// lock word.2683static void __kmp_init_direct_lock(kmp_dyna_lock_t *lck,2684                                   kmp_dyna_lockseq_t seq) {2685  TCW_4(((kmp_base_tas_lock_t *)lck)->poll, KMP_GET_D_TAG(seq));2686  KA_TRACE(2687      20,2688      ("__kmp_init_direct_lock: initialized direct lock with type#%d\n", seq));2689}2690 2691#if KMP_USE_TSX2692 2693// HLE lock functions - imported from the testbed runtime.2694#define HLE_ACQUIRE ".byte 0xf2;"2695#define HLE_RELEASE ".byte 0xf3;"2696 2697static inline kmp_uint32 swap4(kmp_uint32 volatile *p, kmp_uint32 v) {2698  __asm__ volatile(HLE_ACQUIRE "xchg %1,%0" : "+r"(v), "+m"(*p) : : "memory");2699  return v;2700}2701 2702static void __kmp_destroy_hle_lock(kmp_dyna_lock_t *lck) { TCW_4(*lck, 0); }2703 2704static void __kmp_destroy_hle_lock_with_checks(kmp_dyna_lock_t *lck) {2705  TCW_4(*lck, 0);2706}2707 2708static void __kmp_acquire_hle_lock(kmp_dyna_lock_t *lck, kmp_int32 gtid) {2709  // Use gtid for KMP_LOCK_BUSY if necessary2710  if (swap4(lck, KMP_LOCK_BUSY(1, hle)) != KMP_LOCK_FREE(hle)) {2711    int delay = 1;2712    do {2713      while (*(kmp_uint32 volatile *)lck != KMP_LOCK_FREE(hle)) {2714        for (int i = delay; i != 0; --i)2715          KMP_CPU_PAUSE();2716        delay = ((delay << 1) | 1) & 7;2717      }2718    } while (swap4(lck, KMP_LOCK_BUSY(1, hle)) != KMP_LOCK_FREE(hle));2719  }2720}2721 2722static void __kmp_acquire_hle_lock_with_checks(kmp_dyna_lock_t *lck,2723                                               kmp_int32 gtid) {2724  __kmp_acquire_hle_lock(lck, gtid); // TODO: add checks2725}2726 2727static int __kmp_release_hle_lock(kmp_dyna_lock_t *lck, kmp_int32 gtid) {2728  __asm__ volatile(HLE_RELEASE "movl %1,%0"2729                   : "=m"(*lck)2730                   : "r"(KMP_LOCK_FREE(hle))2731                   : "memory");2732  return KMP_LOCK_RELEASED;2733}2734 2735static int __kmp_release_hle_lock_with_checks(kmp_dyna_lock_t *lck,2736                                              kmp_int32 gtid) {2737  return __kmp_release_hle_lock(lck, gtid); // TODO: add checks2738}2739 2740static int __kmp_test_hle_lock(kmp_dyna_lock_t *lck, kmp_int32 gtid) {2741  return swap4(lck, KMP_LOCK_BUSY(1, hle)) == KMP_LOCK_FREE(hle);2742}2743 2744static int __kmp_test_hle_lock_with_checks(kmp_dyna_lock_t *lck,2745                                           kmp_int32 gtid) {2746  return __kmp_test_hle_lock(lck, gtid); // TODO: add checks2747}2748 2749static void __kmp_init_rtm_queuing_lock(kmp_queuing_lock_t *lck) {2750  __kmp_init_queuing_lock(lck);2751}2752 2753static void __kmp_destroy_rtm_queuing_lock(kmp_queuing_lock_t *lck) {2754  __kmp_destroy_queuing_lock(lck);2755}2756 2757static void2758__kmp_destroy_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck) {2759  __kmp_destroy_queuing_lock_with_checks(lck);2760}2761 2762KMP_ATTRIBUTE_TARGET_RTM2763static void __kmp_acquire_rtm_queuing_lock(kmp_queuing_lock_t *lck,2764                                           kmp_int32 gtid) {2765  unsigned retries = 3, status;2766  do {2767    status = _xbegin();2768    if (status == _XBEGIN_STARTED) {2769      if (__kmp_is_unlocked_queuing_lock(lck))2770        return;2771      _xabort(0xff);2772    }2773    if ((status & _XABORT_EXPLICIT) && _XABORT_CODE(status) == 0xff) {2774      // Wait until lock becomes free2775      while (!__kmp_is_unlocked_queuing_lock(lck)) {2776        KMP_YIELD(TRUE);2777      }2778    } else if (!(status & _XABORT_RETRY))2779      break;2780  } while (retries--);2781 2782  // Fall-back non-speculative lock (xchg)2783  __kmp_acquire_queuing_lock(lck, gtid);2784}2785 2786static void __kmp_acquire_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck,2787                                                       kmp_int32 gtid) {2788  __kmp_acquire_rtm_queuing_lock(lck, gtid);2789}2790 2791KMP_ATTRIBUTE_TARGET_RTM2792static int __kmp_release_rtm_queuing_lock(kmp_queuing_lock_t *lck,2793                                          kmp_int32 gtid) {2794  if (__kmp_is_unlocked_queuing_lock(lck)) {2795    // Releasing from speculation2796    _xend();2797  } else {2798    // Releasing from a real lock2799    __kmp_release_queuing_lock(lck, gtid);2800  }2801  return KMP_LOCK_RELEASED;2802}2803 2804static int __kmp_release_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck,2805                                                      kmp_int32 gtid) {2806  return __kmp_release_rtm_queuing_lock(lck, gtid);2807}2808 2809KMP_ATTRIBUTE_TARGET_RTM2810static int __kmp_test_rtm_queuing_lock(kmp_queuing_lock_t *lck,2811                                       kmp_int32 gtid) {2812  unsigned retries = 3, status;2813  do {2814    status = _xbegin();2815    if (status == _XBEGIN_STARTED && __kmp_is_unlocked_queuing_lock(lck)) {2816      return 1;2817    }2818    if (!(status & _XABORT_RETRY))2819      break;2820  } while (retries--);2821 2822  return __kmp_test_queuing_lock(lck, gtid);2823}2824 2825static int __kmp_test_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck,2826                                                   kmp_int32 gtid) {2827  return __kmp_test_rtm_queuing_lock(lck, gtid);2828}2829 2830// Reuse kmp_tas_lock_t for TSX lock which use RTM with fall-back spin lock.2831typedef kmp_tas_lock_t kmp_rtm_spin_lock_t;2832 2833static void __kmp_destroy_rtm_spin_lock(kmp_rtm_spin_lock_t *lck) {2834  KMP_ATOMIC_ST_REL(&lck->lk.poll, 0);2835}2836 2837static void __kmp_destroy_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck) {2838  __kmp_destroy_rtm_spin_lock(lck);2839}2840 2841KMP_ATTRIBUTE_TARGET_RTM2842static int __kmp_acquire_rtm_spin_lock(kmp_rtm_spin_lock_t *lck,2843                                       kmp_int32 gtid) {2844  unsigned retries = 3, status;2845  kmp_int32 lock_free = KMP_LOCK_FREE(rtm_spin);2846  kmp_int32 lock_busy = KMP_LOCK_BUSY(1, rtm_spin);2847  do {2848    status = _xbegin();2849    if (status == _XBEGIN_STARTED) {2850      if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == lock_free)2851        return KMP_LOCK_ACQUIRED_FIRST;2852      _xabort(0xff);2853    }2854    if ((status & _XABORT_EXPLICIT) && _XABORT_CODE(status) == 0xff) {2855      // Wait until lock becomes free2856      while (KMP_ATOMIC_LD_RLX(&lck->lk.poll) != lock_free) {2857        KMP_YIELD(TRUE);2858      }2859    } else if (!(status & _XABORT_RETRY))2860      break;2861  } while (retries--);2862 2863  // Fall-back spin lock2864  KMP_FSYNC_PREPARE(lck);2865  kmp_backoff_t backoff = __kmp_spin_backoff_params;2866  while (KMP_ATOMIC_LD_RLX(&lck->lk.poll) != lock_free ||2867         !__kmp_atomic_compare_store_acq(&lck->lk.poll, lock_free, lock_busy)) {2868    __kmp_spin_backoff(&backoff);2869  }2870  KMP_FSYNC_ACQUIRED(lck);2871  return KMP_LOCK_ACQUIRED_FIRST;2872}2873 2874static int __kmp_acquire_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck,2875                                                   kmp_int32 gtid) {2876  return __kmp_acquire_rtm_spin_lock(lck, gtid);2877}2878 2879KMP_ATTRIBUTE_TARGET_RTM2880static int __kmp_release_rtm_spin_lock(kmp_rtm_spin_lock_t *lck,2881                                       kmp_int32 gtid) {2882  if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == KMP_LOCK_FREE(rtm_spin)) {2883    // Releasing from speculation2884    _xend();2885  } else {2886    // Releasing from a real lock2887    KMP_FSYNC_RELEASING(lck);2888    KMP_ATOMIC_ST_REL(&lck->lk.poll, KMP_LOCK_FREE(rtm_spin));2889  }2890  return KMP_LOCK_RELEASED;2891}2892 2893static int __kmp_release_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck,2894                                                   kmp_int32 gtid) {2895  return __kmp_release_rtm_spin_lock(lck, gtid);2896}2897 2898KMP_ATTRIBUTE_TARGET_RTM2899static int __kmp_test_rtm_spin_lock(kmp_rtm_spin_lock_t *lck, kmp_int32 gtid) {2900  unsigned retries = 3, status;2901  kmp_int32 lock_free = KMP_LOCK_FREE(rtm_spin);2902  kmp_int32 lock_busy = KMP_LOCK_BUSY(1, rtm_spin);2903  do {2904    status = _xbegin();2905    if (status == _XBEGIN_STARTED &&2906        KMP_ATOMIC_LD_RLX(&lck->lk.poll) == lock_free) {2907      return TRUE;2908    }2909    if (!(status & _XABORT_RETRY))2910      break;2911  } while (retries--);2912 2913  if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == lock_free &&2914      __kmp_atomic_compare_store_acq(&lck->lk.poll, lock_free, lock_busy)) {2915    KMP_FSYNC_ACQUIRED(lck);2916    return TRUE;2917  }2918  return FALSE;2919}2920 2921static int __kmp_test_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck,2922                                                kmp_int32 gtid) {2923  return __kmp_test_rtm_spin_lock(lck, gtid);2924}2925 2926#endif // KMP_USE_TSX2927 2928// Entry functions for indirect locks (first element of direct lock jump tables)2929static void __kmp_init_indirect_lock(kmp_dyna_lock_t *l,2930                                     kmp_dyna_lockseq_t tag);2931static void __kmp_destroy_indirect_lock(kmp_dyna_lock_t *lock);2932static int __kmp_set_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32);2933static int __kmp_unset_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32);2934static int __kmp_test_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32);2935static int __kmp_set_indirect_lock_with_checks(kmp_dyna_lock_t *lock,2936                                               kmp_int32);2937static int __kmp_unset_indirect_lock_with_checks(kmp_dyna_lock_t *lock,2938                                                 kmp_int32);2939static int __kmp_test_indirect_lock_with_checks(kmp_dyna_lock_t *lock,2940                                                kmp_int32);2941 2942// Lock function definitions for the union parameter type2943#define KMP_FOREACH_LOCK_KIND(m, a) m(ticket, a) m(queuing, a) m(drdpa, a)2944 2945#define expand1(lk, op)                                                        \2946  static void __kmp_##op##_##lk##_##lock(kmp_user_lock_p lock) {               \2947    __kmp_##op##_##lk##_##lock(&lock->lk);                                     \2948  }2949#define expand2(lk, op)                                                        \2950  static int __kmp_##op##_##lk##_##lock(kmp_user_lock_p lock,                  \2951                                        kmp_int32 gtid) {                      \2952    return __kmp_##op##_##lk##_##lock(&lock->lk, gtid);                        \2953  }2954#define expand3(lk, op)                                                        \2955  static void __kmp_set_##lk##_##lock_flags(kmp_user_lock_p lock,              \2956                                            kmp_lock_flags_t flags) {          \2957    __kmp_set_##lk##_lock_flags(&lock->lk, flags);                             \2958  }2959#define expand4(lk, op)                                                        \2960  static void __kmp_set_##lk##_##lock_location(kmp_user_lock_p lock,           \2961                                               const ident_t *loc) {           \2962    __kmp_set_##lk##_lock_location(&lock->lk, loc);                            \2963  }2964 2965KMP_FOREACH_LOCK_KIND(expand1, init)2966KMP_FOREACH_LOCK_KIND(expand1, init_nested)2967KMP_FOREACH_LOCK_KIND(expand1, destroy)2968KMP_FOREACH_LOCK_KIND(expand1, destroy_nested)2969KMP_FOREACH_LOCK_KIND(expand2, acquire)2970KMP_FOREACH_LOCK_KIND(expand2, acquire_nested)2971KMP_FOREACH_LOCK_KIND(expand2, release)2972KMP_FOREACH_LOCK_KIND(expand2, release_nested)2973KMP_FOREACH_LOCK_KIND(expand2, test)2974KMP_FOREACH_LOCK_KIND(expand2, test_nested)2975KMP_FOREACH_LOCK_KIND(expand3, )2976KMP_FOREACH_LOCK_KIND(expand4, )2977 2978#undef expand12979#undef expand22980#undef expand32981#undef expand42982 2983// Jump tables for the indirect lock functions2984// Only fill in the odd entries, that avoids the need to shift out the low bit2985 2986// init functions2987#define expand(l, op) 0, __kmp_init_direct_lock,2988void (*__kmp_direct_init[])(kmp_dyna_lock_t *, kmp_dyna_lockseq_t) = {2989    __kmp_init_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, init)};2990#undef expand2991 2992// destroy functions2993#define expand(l, op) 0, (void (*)(kmp_dyna_lock_t *))__kmp_##op##_##l##_lock,2994static void (*direct_destroy[])(kmp_dyna_lock_t *) = {2995    __kmp_destroy_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, destroy)};2996#undef expand2997#define expand(l, op)                                                          \2998  0, (void (*)(kmp_dyna_lock_t *))__kmp_destroy_##l##_lock_with_checks,2999static void (*direct_destroy_check[])(kmp_dyna_lock_t *) = {3000    __kmp_destroy_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, destroy)};3001#undef expand3002 3003// set/acquire functions3004#define expand(l, op)                                                          \3005  0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock,3006static int (*direct_set[])(kmp_dyna_lock_t *, kmp_int32) = {3007    __kmp_set_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, acquire)};3008#undef expand3009#define expand(l, op)                                                          \3010  0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock_with_checks,3011static int (*direct_set_check[])(kmp_dyna_lock_t *, kmp_int32) = {3012    __kmp_set_indirect_lock_with_checks, 0,3013    KMP_FOREACH_D_LOCK(expand, acquire)};3014#undef expand3015 3016// unset/release and test functions3017#define expand(l, op)                                                          \3018  0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock,3019static int (*direct_unset[])(kmp_dyna_lock_t *, kmp_int32) = {3020    __kmp_unset_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, release)};3021static int (*direct_test[])(kmp_dyna_lock_t *, kmp_int32) = {3022    __kmp_test_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, test)};3023#undef expand3024#define expand(l, op)                                                          \3025  0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock_with_checks,3026static int (*direct_unset_check[])(kmp_dyna_lock_t *, kmp_int32) = {3027    __kmp_unset_indirect_lock_with_checks, 0,3028    KMP_FOREACH_D_LOCK(expand, release)};3029static int (*direct_test_check[])(kmp_dyna_lock_t *, kmp_int32) = {3030    __kmp_test_indirect_lock_with_checks, 0, KMP_FOREACH_D_LOCK(expand, test)};3031#undef expand3032 3033// Exposes only one set of jump tables (*lock or *lock_with_checks).3034void (**__kmp_direct_destroy)(kmp_dyna_lock_t *) = 0;3035int (**__kmp_direct_set)(kmp_dyna_lock_t *, kmp_int32) = 0;3036int (**__kmp_direct_unset)(kmp_dyna_lock_t *, kmp_int32) = 0;3037int (**__kmp_direct_test)(kmp_dyna_lock_t *, kmp_int32) = 0;3038 3039// Jump tables for the indirect lock functions3040#define expand(l, op) (void (*)(kmp_user_lock_p)) __kmp_##op##_##l##_##lock,3041void (*__kmp_indirect_init[])(kmp_user_lock_p) = {3042    KMP_FOREACH_I_LOCK(expand, init)};3043#undef expand3044 3045#define expand(l, op) (void (*)(kmp_user_lock_p)) __kmp_##op##_##l##_##lock,3046static void (*indirect_destroy[])(kmp_user_lock_p) = {3047    KMP_FOREACH_I_LOCK(expand, destroy)};3048#undef expand3049#define expand(l, op)                                                          \3050  (void (*)(kmp_user_lock_p)) __kmp_##op##_##l##_##lock_with_checks,3051static void (*indirect_destroy_check[])(kmp_user_lock_p) = {3052    KMP_FOREACH_I_LOCK(expand, destroy)};3053#undef expand3054 3055// set/acquire functions3056#define expand(l, op)                                                          \3057  (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock,3058static int (*indirect_set[])(kmp_user_lock_p,3059                             kmp_int32) = {KMP_FOREACH_I_LOCK(expand, acquire)};3060#undef expand3061#define expand(l, op)                                                          \3062  (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock_with_checks,3063static int (*indirect_set_check[])(kmp_user_lock_p, kmp_int32) = {3064    KMP_FOREACH_I_LOCK(expand, acquire)};3065#undef expand3066 3067// unset/release and test functions3068#define expand(l, op)                                                          \3069  (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock,3070static int (*indirect_unset[])(kmp_user_lock_p, kmp_int32) = {3071    KMP_FOREACH_I_LOCK(expand, release)};3072static int (*indirect_test[])(kmp_user_lock_p,3073                              kmp_int32) = {KMP_FOREACH_I_LOCK(expand, test)};3074#undef expand3075#define expand(l, op)                                                          \3076  (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock_with_checks,3077static int (*indirect_unset_check[])(kmp_user_lock_p, kmp_int32) = {3078    KMP_FOREACH_I_LOCK(expand, release)};3079static int (*indirect_test_check[])(kmp_user_lock_p, kmp_int32) = {3080    KMP_FOREACH_I_LOCK(expand, test)};3081#undef expand3082 3083// Exposes only one jump tables (*lock or *lock_with_checks).3084void (**__kmp_indirect_destroy)(kmp_user_lock_p) = 0;3085int (**__kmp_indirect_set)(kmp_user_lock_p, kmp_int32) = 0;3086int (**__kmp_indirect_unset)(kmp_user_lock_p, kmp_int32) = 0;3087int (**__kmp_indirect_test)(kmp_user_lock_p, kmp_int32) = 0;3088 3089// Lock index table.3090kmp_indirect_lock_table_t __kmp_i_lock_table;3091 3092// Size of indirect locks.3093static kmp_uint32 __kmp_indirect_lock_size[KMP_NUM_I_LOCKS] = {0};3094 3095// Jump tables for lock accessor/modifier.3096void (*__kmp_indirect_set_location[KMP_NUM_I_LOCKS])(kmp_user_lock_p,3097                                                     const ident_t *) = {0};3098void (*__kmp_indirect_set_flags[KMP_NUM_I_LOCKS])(kmp_user_lock_p,3099                                                  kmp_lock_flags_t) = {0};3100const ident_t *(*__kmp_indirect_get_location[KMP_NUM_I_LOCKS])(3101    kmp_user_lock_p) = {0};3102kmp_lock_flags_t (*__kmp_indirect_get_flags[KMP_NUM_I_LOCKS])(3103    kmp_user_lock_p) = {0};3104 3105// Use different lock pools for different lock types.3106static kmp_indirect_lock_t *__kmp_indirect_lock_pool[KMP_NUM_I_LOCKS] = {0};3107 3108// User lock allocator for dynamically dispatched indirect locks. Every entry of3109// the indirect lock table holds the address and type of the allocated indirect3110// lock (kmp_indirect_lock_t), and the size of the table doubles when it is3111// full. A destroyed indirect lock object is returned to the reusable pool of3112// locks, unique to each lock type.3113kmp_indirect_lock_t *__kmp_allocate_indirect_lock(void **user_lock,3114                                                  kmp_int32 gtid,3115                                                  kmp_indirect_locktag_t tag) {3116  kmp_indirect_lock_t *lck;3117  kmp_lock_index_t idx, table_idx;3118 3119  __kmp_acquire_lock(&__kmp_global_lock, gtid);3120 3121  if (__kmp_indirect_lock_pool[tag] != NULL) {3122    // Reuse the allocated and destroyed lock object3123    lck = __kmp_indirect_lock_pool[tag];3124    if (OMP_LOCK_T_SIZE < sizeof(void *))3125      idx = lck->lock->pool.index;3126    __kmp_indirect_lock_pool[tag] = (kmp_indirect_lock_t *)lck->lock->pool.next;3127    KA_TRACE(20, ("__kmp_allocate_indirect_lock: reusing an existing lock %p\n",3128                  lck));3129  } else {3130    kmp_uint32 row, col;3131    kmp_indirect_lock_table_t *lock_table = &__kmp_i_lock_table;3132    idx = 0;3133    // Find location in list of lock tables to put new lock3134    while (1) {3135      table_idx = lock_table->next; // index within this table3136      idx += lock_table->next; // global index within list of tables3137      if (table_idx < lock_table->nrow_ptrs * KMP_I_LOCK_CHUNK) {3138        row = table_idx / KMP_I_LOCK_CHUNK;3139        col = table_idx % KMP_I_LOCK_CHUNK;3140        // Allocate a new row of locks if necessary3141        if (!lock_table->table[row]) {3142          lock_table->table[row] = (kmp_indirect_lock_t *)__kmp_allocate(3143              sizeof(kmp_indirect_lock_t) * KMP_I_LOCK_CHUNK);3144        }3145        break;3146      }3147      // Allocate a new lock table if necessary with double the capacity3148      if (!lock_table->next_table) {3149        kmp_indirect_lock_table_t *next_table =3150            (kmp_indirect_lock_table_t *)__kmp_allocate(3151                sizeof(kmp_indirect_lock_table_t));3152        next_table->table = (kmp_indirect_lock_t **)__kmp_allocate(3153            sizeof(kmp_indirect_lock_t *) * 2 * lock_table->nrow_ptrs);3154        next_table->nrow_ptrs = 2 * lock_table->nrow_ptrs;3155        next_table->next = 0;3156        next_table->next_table = nullptr;3157        lock_table->next_table = next_table;3158      }3159      lock_table = lock_table->next_table;3160      KMP_ASSERT(lock_table);3161    }3162    lock_table->next++;3163 3164    lck = &lock_table->table[row][col];3165    // Allocate a new base lock object3166    lck->lock = (kmp_user_lock_p)__kmp_allocate(__kmp_indirect_lock_size[tag]);3167    KA_TRACE(20,3168             ("__kmp_allocate_indirect_lock: allocated a new lock %p\n", lck));3169  }3170 3171  __kmp_release_lock(&__kmp_global_lock, gtid);3172 3173  lck->type = tag;3174 3175  if (OMP_LOCK_T_SIZE < sizeof(void *)) {3176    *(kmp_lock_index_t *)&(((kmp_base_tas_lock_t *)user_lock)->poll) =3177        idx << 1; // indirect lock word must be even3178  } else {3179    *((kmp_indirect_lock_t **)user_lock) = lck;3180  }3181 3182  return lck;3183}3184 3185// User lock lookup for dynamically dispatched locks.3186static __forceinline kmp_indirect_lock_t *3187__kmp_lookup_indirect_lock(void **user_lock, const char *func) {3188  if (__kmp_env_consistency_check) {3189    kmp_indirect_lock_t *lck = NULL;3190    if (user_lock == NULL) {3191      KMP_FATAL(LockIsUninitialized, func);3192    }3193    if (OMP_LOCK_T_SIZE < sizeof(void *)) {3194      kmp_lock_index_t idx = KMP_EXTRACT_I_INDEX(user_lock);3195      lck = __kmp_get_i_lock(idx);3196    } else {3197      lck = *((kmp_indirect_lock_t **)user_lock);3198    }3199    if (lck == NULL) {3200      KMP_FATAL(LockIsUninitialized, func);3201    }3202    return lck;3203  } else {3204    if (OMP_LOCK_T_SIZE < sizeof(void *)) {3205      return __kmp_get_i_lock(KMP_EXTRACT_I_INDEX(user_lock));3206    } else {3207      return *((kmp_indirect_lock_t **)user_lock);3208    }3209  }3210}3211 3212static void __kmp_init_indirect_lock(kmp_dyna_lock_t *lock,3213                                     kmp_dyna_lockseq_t seq) {3214#if KMP_USE_ADAPTIVE_LOCKS3215  if (seq == lockseq_adaptive && !__kmp_cpuinfo.flags.rtm) {3216    KMP_WARNING(AdaptiveNotSupported, "kmp_lockseq_t", "adaptive");3217    seq = lockseq_queuing;3218  }3219#endif3220#if KMP_USE_TSX3221  if (seq == lockseq_rtm_queuing && !__kmp_cpuinfo.flags.rtm) {3222    seq = lockseq_queuing;3223  }3224#endif3225  kmp_indirect_locktag_t tag = KMP_GET_I_TAG(seq);3226  kmp_indirect_lock_t *l =3227      __kmp_allocate_indirect_lock((void **)lock, __kmp_entry_gtid(), tag);3228  KMP_I_LOCK_FUNC(l, init)(l->lock);3229  KA_TRACE(3230      20, ("__kmp_init_indirect_lock: initialized indirect lock with type#%d\n",3231           seq));3232}3233 3234static void __kmp_destroy_indirect_lock(kmp_dyna_lock_t *lock) {3235  kmp_uint32 gtid = __kmp_entry_gtid();3236  kmp_indirect_lock_t *l =3237      __kmp_lookup_indirect_lock((void **)lock, "omp_destroy_lock");3238  if (l == nullptr)3239    return; // avoid segv if lock already destroyed3240  KMP_I_LOCK_FUNC(l, destroy)(l->lock);3241  kmp_indirect_locktag_t tag = l->type;3242 3243  __kmp_acquire_lock(&__kmp_global_lock, gtid);3244 3245  // Use the base lock's space to keep the pool chain.3246  l->lock->pool.next = (kmp_user_lock_p)__kmp_indirect_lock_pool[tag];3247  if (OMP_LOCK_T_SIZE < sizeof(void *)) {3248    l->lock->pool.index = KMP_EXTRACT_I_INDEX(lock);3249  }3250  __kmp_indirect_lock_pool[tag] = l;3251 3252  __kmp_release_lock(&__kmp_global_lock, gtid);3253}3254 3255static int __kmp_set_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32 gtid) {3256  kmp_indirect_lock_t *l = KMP_LOOKUP_I_LOCK(lock);3257  return KMP_I_LOCK_FUNC(l, set)(l->lock, gtid);3258}3259 3260static int __kmp_unset_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32 gtid) {3261  kmp_indirect_lock_t *l = KMP_LOOKUP_I_LOCK(lock);3262  return KMP_I_LOCK_FUNC(l, unset)(l->lock, gtid);3263}3264 3265static int __kmp_test_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32 gtid) {3266  kmp_indirect_lock_t *l = KMP_LOOKUP_I_LOCK(lock);3267  return KMP_I_LOCK_FUNC(l, test)(l->lock, gtid);3268}3269 3270static int __kmp_set_indirect_lock_with_checks(kmp_dyna_lock_t *lock,3271                                               kmp_int32 gtid) {3272  kmp_indirect_lock_t *l =3273      __kmp_lookup_indirect_lock((void **)lock, "omp_set_lock");3274  return KMP_I_LOCK_FUNC(l, set)(l->lock, gtid);3275}3276 3277static int __kmp_unset_indirect_lock_with_checks(kmp_dyna_lock_t *lock,3278                                                 kmp_int32 gtid) {3279  kmp_indirect_lock_t *l =3280      __kmp_lookup_indirect_lock((void **)lock, "omp_unset_lock");3281  return KMP_I_LOCK_FUNC(l, unset)(l->lock, gtid);3282}3283 3284static int __kmp_test_indirect_lock_with_checks(kmp_dyna_lock_t *lock,3285                                                kmp_int32 gtid) {3286  kmp_indirect_lock_t *l =3287      __kmp_lookup_indirect_lock((void **)lock, "omp_test_lock");3288  return KMP_I_LOCK_FUNC(l, test)(l->lock, gtid);3289}3290 3291kmp_dyna_lockseq_t __kmp_user_lock_seq = lockseq_queuing;3292 3293// This is used only in kmp_error.cpp when consistency checking is on.3294kmp_int32 __kmp_get_user_lock_owner(kmp_user_lock_p lck, kmp_uint32 seq) {3295  switch (seq) {3296  case lockseq_tas:3297  case lockseq_nested_tas:3298    return __kmp_get_tas_lock_owner((kmp_tas_lock_t *)lck);3299#if KMP_USE_FUTEX3300  case lockseq_futex:3301  case lockseq_nested_futex:3302    return __kmp_get_futex_lock_owner((kmp_futex_lock_t *)lck);3303#endif3304  case lockseq_ticket:3305  case lockseq_nested_ticket:3306    return __kmp_get_ticket_lock_owner((kmp_ticket_lock_t *)lck);3307  case lockseq_queuing:3308  case lockseq_nested_queuing:3309#if KMP_USE_ADAPTIVE_LOCKS3310  case lockseq_adaptive:3311#endif3312    return __kmp_get_queuing_lock_owner((kmp_queuing_lock_t *)lck);3313  case lockseq_drdpa:3314  case lockseq_nested_drdpa:3315    return __kmp_get_drdpa_lock_owner((kmp_drdpa_lock_t *)lck);3316  default:3317    return 0;3318  }3319}3320 3321// Initializes data for dynamic user locks.3322void __kmp_init_dynamic_user_locks() {3323  // Initialize jump table for the lock functions3324  if (__kmp_env_consistency_check) {3325    __kmp_direct_set = direct_set_check;3326    __kmp_direct_unset = direct_unset_check;3327    __kmp_direct_test = direct_test_check;3328    __kmp_direct_destroy = direct_destroy_check;3329    __kmp_indirect_set = indirect_set_check;3330    __kmp_indirect_unset = indirect_unset_check;3331    __kmp_indirect_test = indirect_test_check;3332    __kmp_indirect_destroy = indirect_destroy_check;3333  } else {3334    __kmp_direct_set = direct_set;3335    __kmp_direct_unset = direct_unset;3336    __kmp_direct_test = direct_test;3337    __kmp_direct_destroy = direct_destroy;3338    __kmp_indirect_set = indirect_set;3339    __kmp_indirect_unset = indirect_unset;3340    __kmp_indirect_test = indirect_test;3341    __kmp_indirect_destroy = indirect_destroy;3342  }3343  // If the user locks have already been initialized, then return. Allow the3344  // switch between different KMP_CONSISTENCY_CHECK values, but do not allocate3345  // new lock tables if they have already been allocated.3346  if (__kmp_init_user_locks)3347    return;3348 3349  // Initialize lock index table3350  __kmp_i_lock_table.nrow_ptrs = KMP_I_LOCK_TABLE_INIT_NROW_PTRS;3351  __kmp_i_lock_table.table = (kmp_indirect_lock_t **)__kmp_allocate(3352      sizeof(kmp_indirect_lock_t *) * KMP_I_LOCK_TABLE_INIT_NROW_PTRS);3353  *(__kmp_i_lock_table.table) = (kmp_indirect_lock_t *)__kmp_allocate(3354      KMP_I_LOCK_CHUNK * sizeof(kmp_indirect_lock_t));3355  __kmp_i_lock_table.next = 0;3356  __kmp_i_lock_table.next_table = nullptr;3357 3358  // Indirect lock size3359  __kmp_indirect_lock_size[locktag_ticket] = sizeof(kmp_ticket_lock_t);3360  __kmp_indirect_lock_size[locktag_queuing] = sizeof(kmp_queuing_lock_t);3361#if KMP_USE_ADAPTIVE_LOCKS3362  __kmp_indirect_lock_size[locktag_adaptive] = sizeof(kmp_adaptive_lock_t);3363#endif3364  __kmp_indirect_lock_size[locktag_drdpa] = sizeof(kmp_drdpa_lock_t);3365#if KMP_USE_TSX3366  __kmp_indirect_lock_size[locktag_rtm_queuing] = sizeof(kmp_queuing_lock_t);3367#endif3368  __kmp_indirect_lock_size[locktag_nested_tas] = sizeof(kmp_tas_lock_t);3369#if KMP_USE_FUTEX3370  __kmp_indirect_lock_size[locktag_nested_futex] = sizeof(kmp_futex_lock_t);3371#endif3372  __kmp_indirect_lock_size[locktag_nested_ticket] = sizeof(kmp_ticket_lock_t);3373  __kmp_indirect_lock_size[locktag_nested_queuing] = sizeof(kmp_queuing_lock_t);3374  __kmp_indirect_lock_size[locktag_nested_drdpa] = sizeof(kmp_drdpa_lock_t);3375 3376// Initialize lock accessor/modifier3377#define fill_jumps(table, expand, sep)                                         \3378  {                                                                            \3379    table[locktag##sep##ticket] = expand(ticket);                              \3380    table[locktag##sep##queuing] = expand(queuing);                            \3381    table[locktag##sep##drdpa] = expand(drdpa);                                \3382  }3383 3384#if KMP_USE_ADAPTIVE_LOCKS3385#define fill_table(table, expand)                                              \3386  {                                                                            \3387    fill_jumps(table, expand, _);                                              \3388    table[locktag_adaptive] = expand(queuing);                                 \3389    fill_jumps(table, expand, _nested_);                                       \3390  }3391#else3392#define fill_table(table, expand)                                              \3393  {                                                                            \3394    fill_jumps(table, expand, _);                                              \3395    fill_jumps(table, expand, _nested_);                                       \3396  }3397#endif // KMP_USE_ADAPTIVE_LOCKS3398 3399#define expand(l)                                                              \3400  (void (*)(kmp_user_lock_p, const ident_t *)) __kmp_set_##l##_lock_location3401  fill_table(__kmp_indirect_set_location, expand);3402#undef expand3403#define expand(l)                                                              \3404  (void (*)(kmp_user_lock_p, kmp_lock_flags_t)) __kmp_set_##l##_lock_flags3405  fill_table(__kmp_indirect_set_flags, expand);3406#undef expand3407#define expand(l)                                                              \3408  (const ident_t *(*)(kmp_user_lock_p)) __kmp_get_##l##_lock_location3409  fill_table(__kmp_indirect_get_location, expand);3410#undef expand3411#define expand(l)                                                              \3412  (kmp_lock_flags_t(*)(kmp_user_lock_p)) __kmp_get_##l##_lock_flags3413  fill_table(__kmp_indirect_get_flags, expand);3414#undef expand3415 3416  __kmp_init_user_locks = TRUE;3417}3418 3419// Clean up the lock table.3420void __kmp_cleanup_indirect_user_locks() {3421  int k;3422 3423  // Clean up locks in the pools first (they were already destroyed before going3424  // into the pools).3425  for (k = 0; k < KMP_NUM_I_LOCKS; ++k) {3426    kmp_indirect_lock_t *l = __kmp_indirect_lock_pool[k];3427    while (l != NULL) {3428      kmp_indirect_lock_t *ll = l;3429      l = (kmp_indirect_lock_t *)l->lock->pool.next;3430      KA_TRACE(20, ("__kmp_cleanup_indirect_user_locks: freeing %p from pool\n",3431                    ll));3432      __kmp_free(ll->lock);3433      ll->lock = NULL;3434    }3435    __kmp_indirect_lock_pool[k] = NULL;3436  }3437  // Clean up the remaining undestroyed locks.3438  kmp_indirect_lock_table_t *ptr = &__kmp_i_lock_table;3439  while (ptr) {3440    for (kmp_uint32 row = 0; row < ptr->nrow_ptrs; ++row) {3441      if (!ptr->table[row])3442        continue;3443      for (kmp_uint32 col = 0; col < KMP_I_LOCK_CHUNK; ++col) {3444        kmp_indirect_lock_t *l = &ptr->table[row][col];3445        if (l->lock) {3446          // Locks not destroyed explicitly need to be destroyed here.3447          KMP_I_LOCK_FUNC(l, destroy)(l->lock);3448          KA_TRACE(20, ("__kmp_cleanup_indirect_user_locks: destroy/freeing %p "3449                        "from table\n",3450                        l));3451          __kmp_free(l->lock);3452        }3453      }3454      __kmp_free(ptr->table[row]);3455    }3456    __kmp_free(ptr->table);3457    kmp_indirect_lock_table_t *next_table = ptr->next_table;3458    if (ptr != &__kmp_i_lock_table)3459      __kmp_free(ptr);3460    ptr = next_table;3461  }3462 3463  __kmp_init_user_locks = FALSE;3464}3465 3466enum kmp_lock_kind __kmp_user_lock_kind = lk_default;3467int __kmp_num_locks_in_block = 1; // FIXME - tune this value3468 3469#else // KMP_USE_DYNAMIC_LOCK3470 3471static void __kmp_init_tas_lock_with_checks(kmp_tas_lock_t *lck) {3472  __kmp_init_tas_lock(lck);3473}3474 3475static void __kmp_init_nested_tas_lock_with_checks(kmp_tas_lock_t *lck) {3476  __kmp_init_nested_tas_lock(lck);3477}3478 3479#if KMP_USE_FUTEX3480static void __kmp_init_futex_lock_with_checks(kmp_futex_lock_t *lck) {3481  __kmp_init_futex_lock(lck);3482}3483 3484static void __kmp_init_nested_futex_lock_with_checks(kmp_futex_lock_t *lck) {3485  __kmp_init_nested_futex_lock(lck);3486}3487#endif3488 3489static int __kmp_is_ticket_lock_initialized(kmp_ticket_lock_t *lck) {3490  return lck == lck->lk.self;3491}3492 3493static void __kmp_init_ticket_lock_with_checks(kmp_ticket_lock_t *lck) {3494  __kmp_init_ticket_lock(lck);3495}3496 3497static void __kmp_init_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck) {3498  __kmp_init_nested_ticket_lock(lck);3499}3500 3501static int __kmp_is_queuing_lock_initialized(kmp_queuing_lock_t *lck) {3502  return lck == lck->lk.initialized;3503}3504 3505static void __kmp_init_queuing_lock_with_checks(kmp_queuing_lock_t *lck) {3506  __kmp_init_queuing_lock(lck);3507}3508 3509static void3510__kmp_init_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck) {3511  __kmp_init_nested_queuing_lock(lck);3512}3513 3514#if KMP_USE_ADAPTIVE_LOCKS3515static void __kmp_init_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck) {3516  __kmp_init_adaptive_lock(lck);3517}3518#endif3519 3520static int __kmp_is_drdpa_lock_initialized(kmp_drdpa_lock_t *lck) {3521  return lck == lck->lk.initialized;3522}3523 3524static void __kmp_init_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) {3525  __kmp_init_drdpa_lock(lck);3526}3527 3528static void __kmp_init_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) {3529  __kmp_init_nested_drdpa_lock(lck);3530}3531 3532/* user locks3533 * They are implemented as a table of function pointers which are set to the3534 * lock functions of the appropriate kind, once that has been determined. */3535 3536enum kmp_lock_kind __kmp_user_lock_kind = lk_default;3537 3538size_t __kmp_base_user_lock_size = 0;3539size_t __kmp_user_lock_size = 0;3540 3541kmp_int32 (*__kmp_get_user_lock_owner_)(kmp_user_lock_p lck) = NULL;3542int (*__kmp_acquire_user_lock_with_checks_)(kmp_user_lock_p lck,3543                                            kmp_int32 gtid) = NULL;3544 3545int (*__kmp_test_user_lock_with_checks_)(kmp_user_lock_p lck,3546                                         kmp_int32 gtid) = NULL;3547int (*__kmp_release_user_lock_with_checks_)(kmp_user_lock_p lck,3548                                            kmp_int32 gtid) = NULL;3549void (*__kmp_init_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL;3550void (*__kmp_destroy_user_lock_)(kmp_user_lock_p lck) = NULL;3551void (*__kmp_destroy_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL;3552int (*__kmp_acquire_nested_user_lock_with_checks_)(kmp_user_lock_p lck,3553                                                   kmp_int32 gtid) = NULL;3554 3555int (*__kmp_test_nested_user_lock_with_checks_)(kmp_user_lock_p lck,3556                                                kmp_int32 gtid) = NULL;3557int (*__kmp_release_nested_user_lock_with_checks_)(kmp_user_lock_p lck,3558                                                   kmp_int32 gtid) = NULL;3559void (*__kmp_init_nested_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL;3560void (*__kmp_destroy_nested_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL;3561 3562int (*__kmp_is_user_lock_initialized_)(kmp_user_lock_p lck) = NULL;3563const ident_t *(*__kmp_get_user_lock_location_)(kmp_user_lock_p lck) = NULL;3564void (*__kmp_set_user_lock_location_)(kmp_user_lock_p lck,3565                                      const ident_t *loc) = NULL;3566kmp_lock_flags_t (*__kmp_get_user_lock_flags_)(kmp_user_lock_p lck) = NULL;3567void (*__kmp_set_user_lock_flags_)(kmp_user_lock_p lck,3568                                   kmp_lock_flags_t flags) = NULL;3569 3570void __kmp_set_user_lock_vptrs(kmp_lock_kind_t user_lock_kind) {3571  switch (user_lock_kind) {3572  case lk_default:3573  default:3574    KMP_ASSERT(0);3575 3576  case lk_tas: {3577    __kmp_base_user_lock_size = sizeof(kmp_base_tas_lock_t);3578    __kmp_user_lock_size = sizeof(kmp_tas_lock_t);3579 3580    __kmp_get_user_lock_owner_ =3581        (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_tas_lock_owner);3582 3583    if (__kmp_env_consistency_check) {3584      KMP_BIND_USER_LOCK_WITH_CHECKS(tas);3585      KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(tas);3586    } else {3587      KMP_BIND_USER_LOCK(tas);3588      KMP_BIND_NESTED_USER_LOCK(tas);3589    }3590 3591    __kmp_destroy_user_lock_ =3592        (void (*)(kmp_user_lock_p))(&__kmp_destroy_tas_lock);3593 3594    __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))NULL;3595 3596    __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))NULL;3597 3598    __kmp_set_user_lock_location_ =3599        (void (*)(kmp_user_lock_p, const ident_t *))NULL;3600 3601    __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))NULL;3602 3603    __kmp_set_user_lock_flags_ =3604        (void (*)(kmp_user_lock_p, kmp_lock_flags_t))NULL;3605  } break;3606 3607#if KMP_USE_FUTEX3608 3609  case lk_futex: {3610    __kmp_base_user_lock_size = sizeof(kmp_base_futex_lock_t);3611    __kmp_user_lock_size = sizeof(kmp_futex_lock_t);3612 3613    __kmp_get_user_lock_owner_ =3614        (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_futex_lock_owner);3615 3616    if (__kmp_env_consistency_check) {3617      KMP_BIND_USER_LOCK_WITH_CHECKS(futex);3618      KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(futex);3619    } else {3620      KMP_BIND_USER_LOCK(futex);3621      KMP_BIND_NESTED_USER_LOCK(futex);3622    }3623 3624    __kmp_destroy_user_lock_ =3625        (void (*)(kmp_user_lock_p))(&__kmp_destroy_futex_lock);3626 3627    __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))NULL;3628 3629    __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))NULL;3630 3631    __kmp_set_user_lock_location_ =3632        (void (*)(kmp_user_lock_p, const ident_t *))NULL;3633 3634    __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))NULL;3635 3636    __kmp_set_user_lock_flags_ =3637        (void (*)(kmp_user_lock_p, kmp_lock_flags_t))NULL;3638  } break;3639 3640#endif // KMP_USE_FUTEX3641 3642  case lk_ticket: {3643    __kmp_base_user_lock_size = sizeof(kmp_base_ticket_lock_t);3644    __kmp_user_lock_size = sizeof(kmp_ticket_lock_t);3645 3646    __kmp_get_user_lock_owner_ =3647        (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_ticket_lock_owner);3648 3649    if (__kmp_env_consistency_check) {3650      KMP_BIND_USER_LOCK_WITH_CHECKS(ticket);3651      KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(ticket);3652    } else {3653      KMP_BIND_USER_LOCK(ticket);3654      KMP_BIND_NESTED_USER_LOCK(ticket);3655    }3656 3657    __kmp_destroy_user_lock_ =3658        (void (*)(kmp_user_lock_p))(&__kmp_destroy_ticket_lock);3659 3660    __kmp_is_user_lock_initialized_ =3661        (int (*)(kmp_user_lock_p))(&__kmp_is_ticket_lock_initialized);3662 3663    __kmp_get_user_lock_location_ =3664        (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_ticket_lock_location);3665 3666    __kmp_set_user_lock_location_ = (void (*)(3667        kmp_user_lock_p, const ident_t *))(&__kmp_set_ticket_lock_location);3668 3669    __kmp_get_user_lock_flags_ =3670        (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_ticket_lock_flags);3671 3672    __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))(3673        &__kmp_set_ticket_lock_flags);3674  } break;3675 3676  case lk_queuing: {3677    __kmp_base_user_lock_size = sizeof(kmp_base_queuing_lock_t);3678    __kmp_user_lock_size = sizeof(kmp_queuing_lock_t);3679 3680    __kmp_get_user_lock_owner_ =3681        (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_owner);3682 3683    if (__kmp_env_consistency_check) {3684      KMP_BIND_USER_LOCK_WITH_CHECKS(queuing);3685      KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(queuing);3686    } else {3687      KMP_BIND_USER_LOCK(queuing);3688      KMP_BIND_NESTED_USER_LOCK(queuing);3689    }3690 3691    __kmp_destroy_user_lock_ =3692        (void (*)(kmp_user_lock_p))(&__kmp_destroy_queuing_lock);3693 3694    __kmp_is_user_lock_initialized_ =3695        (int (*)(kmp_user_lock_p))(&__kmp_is_queuing_lock_initialized);3696 3697    __kmp_get_user_lock_location_ =3698        (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_location);3699 3700    __kmp_set_user_lock_location_ = (void (*)(3701        kmp_user_lock_p, const ident_t *))(&__kmp_set_queuing_lock_location);3702 3703    __kmp_get_user_lock_flags_ =3704        (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_flags);3705 3706    __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))(3707        &__kmp_set_queuing_lock_flags);3708  } break;3709 3710#if KMP_USE_ADAPTIVE_LOCKS3711  case lk_adaptive: {3712    __kmp_base_user_lock_size = sizeof(kmp_base_adaptive_lock_t);3713    __kmp_user_lock_size = sizeof(kmp_adaptive_lock_t);3714 3715    __kmp_get_user_lock_owner_ =3716        (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_owner);3717 3718    if (__kmp_env_consistency_check) {3719      KMP_BIND_USER_LOCK_WITH_CHECKS(adaptive);3720    } else {3721      KMP_BIND_USER_LOCK(adaptive);3722    }3723 3724    __kmp_destroy_user_lock_ =3725        (void (*)(kmp_user_lock_p))(&__kmp_destroy_adaptive_lock);3726 3727    __kmp_is_user_lock_initialized_ =3728        (int (*)(kmp_user_lock_p))(&__kmp_is_queuing_lock_initialized);3729 3730    __kmp_get_user_lock_location_ =3731        (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_location);3732 3733    __kmp_set_user_lock_location_ = (void (*)(3734        kmp_user_lock_p, const ident_t *))(&__kmp_set_queuing_lock_location);3735 3736    __kmp_get_user_lock_flags_ =3737        (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_flags);3738 3739    __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))(3740        &__kmp_set_queuing_lock_flags);3741 3742  } break;3743#endif // KMP_USE_ADAPTIVE_LOCKS3744 3745  case lk_drdpa: {3746    __kmp_base_user_lock_size = sizeof(kmp_base_drdpa_lock_t);3747    __kmp_user_lock_size = sizeof(kmp_drdpa_lock_t);3748 3749    __kmp_get_user_lock_owner_ =3750        (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_drdpa_lock_owner);3751 3752    if (__kmp_env_consistency_check) {3753      KMP_BIND_USER_LOCK_WITH_CHECKS(drdpa);3754      KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(drdpa);3755    } else {3756      KMP_BIND_USER_LOCK(drdpa);3757      KMP_BIND_NESTED_USER_LOCK(drdpa);3758    }3759 3760    __kmp_destroy_user_lock_ =3761        (void (*)(kmp_user_lock_p))(&__kmp_destroy_drdpa_lock);3762 3763    __kmp_is_user_lock_initialized_ =3764        (int (*)(kmp_user_lock_p))(&__kmp_is_drdpa_lock_initialized);3765 3766    __kmp_get_user_lock_location_ =3767        (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_drdpa_lock_location);3768 3769    __kmp_set_user_lock_location_ = (void (*)(3770        kmp_user_lock_p, const ident_t *))(&__kmp_set_drdpa_lock_location);3771 3772    __kmp_get_user_lock_flags_ =3773        (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_drdpa_lock_flags);3774 3775    __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))(3776        &__kmp_set_drdpa_lock_flags);3777  } break;3778  }3779}3780 3781// ----------------------------------------------------------------------------3782// User lock table & lock allocation3783 3784kmp_lock_table_t __kmp_user_lock_table = {1, 0, NULL};3785kmp_user_lock_p __kmp_lock_pool = NULL;3786 3787// Lock block-allocation support.3788kmp_block_of_locks *__kmp_lock_blocks = NULL;3789int __kmp_num_locks_in_block = 1; // FIXME - tune this value3790 3791static kmp_lock_index_t __kmp_lock_table_insert(kmp_user_lock_p lck) {3792  // Assume that kmp_global_lock is held upon entry/exit.3793  kmp_lock_index_t index;3794  if (__kmp_user_lock_table.used >= __kmp_user_lock_table.allocated) {3795    kmp_lock_index_t size;3796    kmp_user_lock_p *table;3797    // Reallocate lock table.3798    if (__kmp_user_lock_table.allocated == 0) {3799      size = 1024;3800    } else {3801      size = __kmp_user_lock_table.allocated * 2;3802    }3803    table = (kmp_user_lock_p *)__kmp_allocate(sizeof(kmp_user_lock_p) * size);3804    KMP_MEMCPY(table + 1, __kmp_user_lock_table.table + 1,3805               sizeof(kmp_user_lock_p) * (__kmp_user_lock_table.used - 1));3806    table[0] = (kmp_user_lock_p)__kmp_user_lock_table.table;3807    // We cannot free the previous table now, since it may be in use by other3808    // threads. So save the pointer to the previous table in the first3809    // element of the new table. All the tables will be organized into a list,3810    // and could be freed when library shutting down.3811    __kmp_user_lock_table.table = table;3812    __kmp_user_lock_table.allocated = size;3813  }3814  KMP_DEBUG_ASSERT(__kmp_user_lock_table.used <3815                   __kmp_user_lock_table.allocated);3816  index = __kmp_user_lock_table.used;3817  __kmp_user_lock_table.table[index] = lck;3818  ++__kmp_user_lock_table.used;3819  return index;3820}3821 3822static kmp_user_lock_p __kmp_lock_block_allocate() {3823  // Assume that kmp_global_lock is held upon entry/exit.3824  static int last_index = 0;3825  if ((last_index >= __kmp_num_locks_in_block) || (__kmp_lock_blocks == NULL)) {3826    // Restart the index.3827    last_index = 0;3828    // Need to allocate a new block.3829    KMP_DEBUG_ASSERT(__kmp_user_lock_size > 0);3830    size_t space_for_locks = __kmp_user_lock_size * __kmp_num_locks_in_block;3831    char *buffer =3832        (char *)__kmp_allocate(space_for_locks + sizeof(kmp_block_of_locks));3833    // Set up the new block.3834    kmp_block_of_locks *new_block =3835        (kmp_block_of_locks *)(&buffer[space_for_locks]);3836    new_block->next_block = __kmp_lock_blocks;3837    new_block->locks = (void *)buffer;3838    // Publish the new block.3839    KMP_MB();3840    __kmp_lock_blocks = new_block;3841  }3842  kmp_user_lock_p ret = (kmp_user_lock_p)(&(3843      ((char *)(__kmp_lock_blocks->locks))[last_index * __kmp_user_lock_size]));3844  last_index++;3845  return ret;3846}3847 3848// Get memory for a lock. It may be freshly allocated memory or reused memory3849// from lock pool.3850kmp_user_lock_p __kmp_user_lock_allocate(void **user_lock, kmp_int32 gtid,3851                                         kmp_lock_flags_t flags) {3852  kmp_user_lock_p lck;3853  kmp_lock_index_t index;3854  KMP_DEBUG_ASSERT(user_lock);3855 3856  __kmp_acquire_lock(&__kmp_global_lock, gtid);3857 3858  if (__kmp_lock_pool == NULL) {3859    // Lock pool is empty. Allocate new memory.3860 3861    if (__kmp_num_locks_in_block <= 1) { // Tune this cutoff point.3862      lck = (kmp_user_lock_p)__kmp_allocate(__kmp_user_lock_size);3863    } else {3864      lck = __kmp_lock_block_allocate();3865    }3866 3867    // Insert lock in the table so that it can be freed in __kmp_cleanup,3868    // and debugger has info on all allocated locks.3869    index = __kmp_lock_table_insert(lck);3870  } else {3871    // Pick up lock from pool.3872    lck = __kmp_lock_pool;3873    index = __kmp_lock_pool->pool.index;3874    __kmp_lock_pool = __kmp_lock_pool->pool.next;3875  }3876 3877  // We could potentially differentiate between nested and regular locks3878  // here, and do the lock table lookup for regular locks only.3879  if (OMP_LOCK_T_SIZE < sizeof(void *)) {3880    *((kmp_lock_index_t *)user_lock) = index;3881  } else {3882    *((kmp_user_lock_p *)user_lock) = lck;3883  }3884 3885  // mark the lock if it is critical section lock.3886  __kmp_set_user_lock_flags(lck, flags);3887 3888  __kmp_release_lock(&__kmp_global_lock, gtid); // AC: TODO move this line upper3889 3890  return lck;3891}3892 3893// Put lock's memory to pool for reusing.3894void __kmp_user_lock_free(void **user_lock, kmp_int32 gtid,3895                          kmp_user_lock_p lck) {3896  KMP_DEBUG_ASSERT(user_lock != NULL);3897  KMP_DEBUG_ASSERT(lck != NULL);3898 3899  __kmp_acquire_lock(&__kmp_global_lock, gtid);3900 3901  lck->pool.next = __kmp_lock_pool;3902  __kmp_lock_pool = lck;3903  if (OMP_LOCK_T_SIZE < sizeof(void *)) {3904    kmp_lock_index_t index = *((kmp_lock_index_t *)user_lock);3905    KMP_DEBUG_ASSERT(0 < index && index <= __kmp_user_lock_table.used);3906    lck->pool.index = index;3907  }3908 3909  __kmp_release_lock(&__kmp_global_lock, gtid);3910}3911 3912kmp_user_lock_p __kmp_lookup_user_lock(void **user_lock, char const *func) {3913  kmp_user_lock_p lck = NULL;3914 3915  if (__kmp_env_consistency_check) {3916    if (user_lock == NULL) {3917      KMP_FATAL(LockIsUninitialized, func);3918    }3919  }3920 3921  if (OMP_LOCK_T_SIZE < sizeof(void *)) {3922    kmp_lock_index_t index = *((kmp_lock_index_t *)user_lock);3923    if (__kmp_env_consistency_check) {3924      if (!(0 < index && index < __kmp_user_lock_table.used)) {3925        KMP_FATAL(LockIsUninitialized, func);3926      }3927    }3928    KMP_DEBUG_ASSERT(0 < index && index < __kmp_user_lock_table.used);3929    KMP_DEBUG_ASSERT(__kmp_user_lock_size > 0);3930    lck = __kmp_user_lock_table.table[index];3931  } else {3932    lck = *((kmp_user_lock_p *)user_lock);3933  }3934 3935  if (__kmp_env_consistency_check) {3936    if (lck == NULL) {3937      KMP_FATAL(LockIsUninitialized, func);3938    }3939  }3940 3941  return lck;3942}3943 3944void __kmp_cleanup_user_locks(void) {3945  // Reset lock pool. Don't worry about lock in the pool--we will free them when3946  // iterating through lock table (it includes all the locks, dead or alive).3947  __kmp_lock_pool = NULL;3948 3949#define IS_CRITICAL(lck)                                                       \3950  ((__kmp_get_user_lock_flags_ != NULL) &&                                     \3951   ((*__kmp_get_user_lock_flags_)(lck)&kmp_lf_critical_section))3952 3953  // Loop through lock table, free all locks.3954  // Do not free item [0], it is reserved for lock tables list.3955  //3956  // FIXME - we are iterating through a list of (pointers to) objects of type3957  // union kmp_user_lock, but we have no way of knowing whether the base type is3958  // currently "pool" or whatever the global user lock type is.3959  //3960  // We are relying on the fact that for all of the user lock types3961  // (except "tas"), the first field in the lock struct is the "initialized"3962  // field, which is set to the address of the lock object itself when3963  // the lock is initialized.  When the union is of type "pool", the3964  // first field is a pointer to the next object in the free list, which3965  // will not be the same address as the object itself.3966  //3967  // This means that the check (*__kmp_is_user_lock_initialized_)(lck) will fail3968  // for "pool" objects on the free list.  This must happen as the "location"3969  // field of real user locks overlaps the "index" field of "pool" objects.3970  //3971  // It would be better to run through the free list, and remove all "pool"3972  // objects from the lock table before executing this loop.  However,3973  // "pool" objects do not always have their index field set (only on3974  // lin_32e), and I don't want to search the lock table for the address3975  // of every "pool" object on the free list.3976  while (__kmp_user_lock_table.used > 1) {3977    const ident *loc;3978 3979    // reduce __kmp_user_lock_table.used before freeing the lock,3980    // so that state of locks is consistent3981    kmp_user_lock_p lck =3982        __kmp_user_lock_table.table[--__kmp_user_lock_table.used];3983 3984    if ((__kmp_is_user_lock_initialized_ != NULL) &&3985        (*__kmp_is_user_lock_initialized_)(lck)) {3986      // Issue a warning if: KMP_CONSISTENCY_CHECK AND lock is initialized AND3987      // it is NOT a critical section (user is not responsible for destroying3988      // criticals) AND we know source location to report.3989      if (__kmp_env_consistency_check && (!IS_CRITICAL(lck)) &&3990          ((loc = __kmp_get_user_lock_location(lck)) != NULL) &&3991          (loc->psource != NULL)) {3992        kmp_str_loc_t str_loc = __kmp_str_loc_init(loc->psource, false);3993        KMP_WARNING(CnsLockNotDestroyed, str_loc.file, str_loc.line);3994        __kmp_str_loc_free(&str_loc);3995      }3996 3997#ifdef KMP_DEBUG3998      if (IS_CRITICAL(lck)) {3999        KA_TRACE(4000            20,4001            ("__kmp_cleanup_user_locks: free critical section lock %p (%p)\n",4002             lck, *(void **)lck));4003      } else {4004        KA_TRACE(20, ("__kmp_cleanup_user_locks: free lock %p (%p)\n", lck,4005                      *(void **)lck));4006      }4007#endif // KMP_DEBUG4008 4009      // Cleanup internal lock dynamic resources (for drdpa locks particularly).4010      __kmp_destroy_user_lock(lck);4011    }4012 4013    // Free the lock if block allocation of locks is not used.4014    if (__kmp_lock_blocks == NULL) {4015      __kmp_free(lck);4016    }4017  }4018 4019#undef IS_CRITICAL4020 4021  // delete lock table(s).4022  kmp_user_lock_p *table_ptr = __kmp_user_lock_table.table;4023  __kmp_user_lock_table.table = NULL;4024  __kmp_user_lock_table.allocated = 0;4025 4026  while (table_ptr != NULL) {4027    // In the first element we saved the pointer to the previous4028    // (smaller) lock table.4029    kmp_user_lock_p *next = (kmp_user_lock_p *)(table_ptr[0]);4030    __kmp_free(table_ptr);4031    table_ptr = next;4032  }4033 4034  // Free buffers allocated for blocks of locks.4035  kmp_block_of_locks_t *block_ptr = __kmp_lock_blocks;4036  __kmp_lock_blocks = NULL;4037 4038  while (block_ptr != NULL) {4039    kmp_block_of_locks_t *next = block_ptr->next_block;4040    __kmp_free(block_ptr->locks);4041    // *block_ptr itself was allocated at the end of the locks vector.4042    block_ptr = next;4043  }4044 4045  TCW_4(__kmp_init_user_locks, FALSE);4046}4047 4048#endif // KMP_USE_DYNAMIC_LOCK4049