/* * kmp_lock.cpp -- lock-related functions */ //===----------------------------------------------------------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// #include #include #include "kmp.h" #include "kmp_i18n.h" #include "kmp_io.h" #include "kmp_itt.h" #include "kmp_lock.h" #include "kmp_wait_release.h" #include "kmp_wrapper_getpid.h" #if KMP_USE_FUTEX #include #include // We should really include , but that causes compatibility problems on // different Linux* OS distributions that either require that you include (or // break when you try to include) . Since all we need is the two // macros below (which are part of the kernel ABI, so can't change) we just // define the constants here and don't include #ifndef FUTEX_WAIT #define FUTEX_WAIT 0 #endif #ifndef FUTEX_WAKE #define FUTEX_WAKE 1 #endif #endif /* Implement spin locks for internal library use. */ /* The algorithm implemented is Lamport's bakery lock [1974]. */ void __kmp_validate_locks(void) { int i; kmp_uint32 x, y; /* Check to make sure unsigned arithmetic does wraps properly */ x = ~((kmp_uint32)0) - 2; y = x - 2; for (i = 0; i < 8; ++i, ++x, ++y) { kmp_uint32 z = (x - y); KMP_ASSERT(z == 2); } KMP_ASSERT(offsetof(kmp_base_queuing_lock, tail_id) % 8 == 0); } /* ------------------------------------------------------------------------ */ /* test and set locks */ // For the non-nested locks, we can only assume that the first 4 bytes were // allocated, since gcc only allocates 4 bytes for omp_lock_t, and the Intel // compiler only allocates a 4 byte pointer on IA-32 architecture. On // Windows* OS on Intel(R) 64, we can assume that all 8 bytes were allocated. // // gcc reserves >= 8 bytes for nested locks, so we can assume that the // entire 8 bytes were allocated for nested locks on all 64-bit platforms. static kmp_int32 __kmp_get_tas_lock_owner(kmp_tas_lock_t *lck) { return KMP_LOCK_STRIP(KMP_ATOMIC_LD_RLX(&lck->lk.poll)) - 1; } static inline bool __kmp_is_tas_lock_nestable(kmp_tas_lock_t *lck) { return lck->lk.depth_locked != -1; } __forceinline static int __kmp_acquire_tas_lock_timed_template(kmp_tas_lock_t *lck, kmp_int32 gtid) { KMP_MB(); #ifdef USE_LOCK_PROFILE kmp_uint32 curr = KMP_LOCK_STRIP(lck->lk.poll); if ((curr != 0) && (curr != gtid + 1)) __kmp_printf("LOCK CONTENTION: %p\n", lck); /* else __kmp_printf( "." );*/ #endif /* USE_LOCK_PROFILE */ kmp_int32 tas_free = KMP_LOCK_FREE(tas); kmp_int32 tas_busy = KMP_LOCK_BUSY(gtid + 1, tas); if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == tas_free && __kmp_atomic_compare_store_acq(&lck->lk.poll, tas_free, tas_busy)) { KMP_FSYNC_ACQUIRED(lck); return KMP_LOCK_ACQUIRED_FIRST; } kmp_uint32 spins; kmp_uint64 time; KMP_FSYNC_PREPARE(lck); KMP_INIT_YIELD(spins); KMP_INIT_BACKOFF(time); kmp_backoff_t backoff = __kmp_spin_backoff_params; do { #if !KMP_HAVE_UMWAIT __kmp_spin_backoff(&backoff); #else if (!__kmp_tpause_enabled) __kmp_spin_backoff(&backoff); #endif KMP_YIELD_OVERSUB_ELSE_SPIN(spins, time); } while (KMP_ATOMIC_LD_RLX(&lck->lk.poll) != tas_free || !__kmp_atomic_compare_store_acq(&lck->lk.poll, tas_free, tas_busy)); KMP_FSYNC_ACQUIRED(lck); return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_acquire_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) { int retval = __kmp_acquire_tas_lock_timed_template(lck, gtid); return retval; } static int __kmp_acquire_tas_lock_with_checks(kmp_tas_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_lock"; if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if ((gtid >= 0) && (__kmp_get_tas_lock_owner(lck) == gtid)) { KMP_FATAL(LockIsAlreadyOwned, func); } return __kmp_acquire_tas_lock(lck, gtid); } int __kmp_test_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) { kmp_int32 tas_free = KMP_LOCK_FREE(tas); kmp_int32 tas_busy = KMP_LOCK_BUSY(gtid + 1, tas); if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == tas_free && __kmp_atomic_compare_store_acq(&lck->lk.poll, tas_free, tas_busy)) { KMP_FSYNC_ACQUIRED(lck); return TRUE; } return FALSE; } static int __kmp_test_tas_lock_with_checks(kmp_tas_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_lock"; if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } return __kmp_test_tas_lock(lck, gtid); } int __kmp_release_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) { KMP_MB(); /* Flush all pending memory write invalidates. */ KMP_FSYNC_RELEASING(lck); KMP_ATOMIC_ST_REL(&lck->lk.poll, KMP_LOCK_FREE(tas)); KMP_MB(); /* Flush all pending memory write invalidates. */ KMP_YIELD_OVERSUB(); return KMP_LOCK_RELEASED; } static int __kmp_release_tas_lock_with_checks(kmp_tas_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_lock"; KMP_MB(); /* in case another processor initialized lock */ if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_tas_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if ((gtid >= 0) && (__kmp_get_tas_lock_owner(lck) >= 0) && (__kmp_get_tas_lock_owner(lck) != gtid)) { KMP_FATAL(LockUnsettingSetByAnother, func); } return __kmp_release_tas_lock(lck, gtid); } void __kmp_init_tas_lock(kmp_tas_lock_t *lck) { lck->lk.poll = KMP_LOCK_FREE(tas); } void __kmp_destroy_tas_lock(kmp_tas_lock_t *lck) { lck->lk.poll = 0; } static void __kmp_destroy_tas_lock_with_checks(kmp_tas_lock_t *lck) { char const *const func = "omp_destroy_lock"; if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_tas_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_tas_lock(lck); } // nested test and set locks int __kmp_acquire_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_tas_lock_owner(lck) == gtid) { lck->lk.depth_locked += 1; return KMP_LOCK_ACQUIRED_NEXT; } else { __kmp_acquire_tas_lock_timed_template(lck, gtid); lck->lk.depth_locked = 1; return KMP_LOCK_ACQUIRED_FIRST; } } static int __kmp_acquire_nested_tas_lock_with_checks(kmp_tas_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_nest_lock"; if (!__kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_acquire_nested_tas_lock(lck, gtid); } int __kmp_test_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) { int retval; KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_tas_lock_owner(lck) == gtid) { retval = ++lck->lk.depth_locked; } else if (!__kmp_test_tas_lock(lck, gtid)) { retval = 0; } else { KMP_MB(); retval = lck->lk.depth_locked = 1; } return retval; } static int __kmp_test_nested_tas_lock_with_checks(kmp_tas_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_nest_lock"; if (!__kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_test_nested_tas_lock(lck, gtid); } int __kmp_release_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); KMP_MB(); if (--(lck->lk.depth_locked) == 0) { __kmp_release_tas_lock(lck, gtid); return KMP_LOCK_RELEASED; } return KMP_LOCK_STILL_HELD; } static int __kmp_release_nested_tas_lock_with_checks(kmp_tas_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_nest_lock"; KMP_MB(); /* in case another processor initialized lock */ if (!__kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_tas_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if (__kmp_get_tas_lock_owner(lck) != gtid) { KMP_FATAL(LockUnsettingSetByAnother, func); } return __kmp_release_nested_tas_lock(lck, gtid); } void __kmp_init_nested_tas_lock(kmp_tas_lock_t *lck) { __kmp_init_tas_lock(lck); lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks } void __kmp_destroy_nested_tas_lock(kmp_tas_lock_t *lck) { __kmp_destroy_tas_lock(lck); lck->lk.depth_locked = 0; } static void __kmp_destroy_nested_tas_lock_with_checks(kmp_tas_lock_t *lck) { char const *const func = "omp_destroy_nest_lock"; if (!__kmp_is_tas_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_tas_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_nested_tas_lock(lck); } #if KMP_USE_FUTEX /* ------------------------------------------------------------------------ */ /* futex locks */ // futex locks are really just test and set locks, with a different method // of handling contention. They take the same amount of space as test and // set locks, and are allocated the same way (i.e. use the area allocated by // the compiler for non-nested locks / allocate nested locks on the heap). static kmp_int32 __kmp_get_futex_lock_owner(kmp_futex_lock_t *lck) { return KMP_LOCK_STRIP((TCR_4(lck->lk.poll) >> 1)) - 1; } static inline bool __kmp_is_futex_lock_nestable(kmp_futex_lock_t *lck) { return lck->lk.depth_locked != -1; } __forceinline static int __kmp_acquire_futex_lock_timed_template(kmp_futex_lock_t *lck, kmp_int32 gtid) { kmp_int32 gtid_code = (gtid + 1) << 1; KMP_MB(); #ifdef USE_LOCK_PROFILE kmp_uint32 curr = KMP_LOCK_STRIP(TCR_4(lck->lk.poll)); if ((curr != 0) && (curr != gtid_code)) __kmp_printf("LOCK CONTENTION: %p\n", lck); /* else __kmp_printf( "." );*/ #endif /* USE_LOCK_PROFILE */ KMP_FSYNC_PREPARE(lck); KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d entering\n", lck, lck->lk.poll, gtid)); kmp_int32 poll_val; while ((poll_val = KMP_COMPARE_AND_STORE_RET32( &(lck->lk.poll), KMP_LOCK_FREE(futex), KMP_LOCK_BUSY(gtid_code, futex))) != KMP_LOCK_FREE(futex)) { kmp_int32 cond = KMP_LOCK_STRIP(poll_val) & 1; KA_TRACE( 1000, ("__kmp_acquire_futex_lock: lck:%p, T#%d poll_val = 0x%x cond = 0x%x\n", lck, gtid, poll_val, cond)); // NOTE: if you try to use the following condition for this branch // // if ( poll_val & 1 == 0 ) // // Then the 12.0 compiler has a bug where the following block will // always be skipped, regardless of the value of the LSB of poll_val. if (!cond) { // Try to set the lsb in the poll to indicate to the owner // thread that they need to wake this thread up. if (!KMP_COMPARE_AND_STORE_REL32(&(lck->lk.poll), poll_val, poll_val | KMP_LOCK_BUSY(1, futex))) { KA_TRACE( 1000, ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d can't set bit 0\n", lck, lck->lk.poll, gtid)); continue; } poll_val |= KMP_LOCK_BUSY(1, futex); KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d bit 0 set\n", lck, lck->lk.poll, gtid)); } KA_TRACE( 1000, ("__kmp_acquire_futex_lock: lck:%p, T#%d before futex_wait(0x%x)\n", lck, gtid, poll_val)); long rc; if ((rc = syscall(__NR_futex, &(lck->lk.poll), FUTEX_WAIT, poll_val, NULL, NULL, 0)) != 0) { KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p, T#%d futex_wait(0x%x) " "failed (rc=%ld errno=%d)\n", lck, gtid, poll_val, rc, errno)); continue; } KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p, T#%d after futex_wait(0x%x)\n", lck, gtid, poll_val)); // This thread has now done a successful futex wait call and was entered on // the OS futex queue. We must now perform a futex wake call when releasing // the lock, as we have no idea how many other threads are in the queue. gtid_code |= 1; } KMP_FSYNC_ACQUIRED(lck); KA_TRACE(1000, ("__kmp_acquire_futex_lock: lck:%p(0x%x), T#%d exiting\n", lck, lck->lk.poll, gtid)); return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_acquire_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) { int retval = __kmp_acquire_futex_lock_timed_template(lck, gtid); return retval; } static int __kmp_acquire_futex_lock_with_checks(kmp_futex_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_lock"; if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if ((gtid >= 0) && (__kmp_get_futex_lock_owner(lck) == gtid)) { KMP_FATAL(LockIsAlreadyOwned, func); } return __kmp_acquire_futex_lock(lck, gtid); } int __kmp_test_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) { if (KMP_COMPARE_AND_STORE_ACQ32(&(lck->lk.poll), KMP_LOCK_FREE(futex), KMP_LOCK_BUSY((gtid + 1) << 1, futex))) { KMP_FSYNC_ACQUIRED(lck); return TRUE; } return FALSE; } static int __kmp_test_futex_lock_with_checks(kmp_futex_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_lock"; if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } return __kmp_test_futex_lock(lck, gtid); } int __kmp_release_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) { KMP_MB(); /* Flush all pending memory write invalidates. */ KA_TRACE(1000, ("__kmp_release_futex_lock: lck:%p(0x%x), T#%d entering\n", lck, lck->lk.poll, gtid)); KMP_FSYNC_RELEASING(lck); kmp_int32 poll_val = KMP_XCHG_FIXED32(&(lck->lk.poll), KMP_LOCK_FREE(futex)); KA_TRACE(1000, ("__kmp_release_futex_lock: lck:%p, T#%d released poll_val = 0x%x\n", lck, gtid, poll_val)); if (KMP_LOCK_STRIP(poll_val) & 1) { KA_TRACE(1000, ("__kmp_release_futex_lock: lck:%p, T#%d futex_wake 1 thread\n", lck, gtid)); syscall(__NR_futex, &(lck->lk.poll), FUTEX_WAKE, KMP_LOCK_BUSY(1, futex), NULL, NULL, 0); } KMP_MB(); /* Flush all pending memory write invalidates. */ KA_TRACE(1000, ("__kmp_release_futex_lock: lck:%p(0x%x), T#%d exiting\n", lck, lck->lk.poll, gtid)); KMP_YIELD_OVERSUB(); return KMP_LOCK_RELEASED; } static int __kmp_release_futex_lock_with_checks(kmp_futex_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_lock"; KMP_MB(); /* in case another processor initialized lock */ if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_futex_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if ((gtid >= 0) && (__kmp_get_futex_lock_owner(lck) >= 0) && (__kmp_get_futex_lock_owner(lck) != gtid)) { KMP_FATAL(LockUnsettingSetByAnother, func); } return __kmp_release_futex_lock(lck, gtid); } void __kmp_init_futex_lock(kmp_futex_lock_t *lck) { TCW_4(lck->lk.poll, KMP_LOCK_FREE(futex)); } void __kmp_destroy_futex_lock(kmp_futex_lock_t *lck) { lck->lk.poll = 0; } static void __kmp_destroy_futex_lock_with_checks(kmp_futex_lock_t *lck) { char const *const func = "omp_destroy_lock"; if ((sizeof(kmp_futex_lock_t) <= OMP_LOCK_T_SIZE) && __kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_futex_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_futex_lock(lck); } // nested futex locks int __kmp_acquire_nested_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_futex_lock_owner(lck) == gtid) { lck->lk.depth_locked += 1; return KMP_LOCK_ACQUIRED_NEXT; } else { __kmp_acquire_futex_lock_timed_template(lck, gtid); lck->lk.depth_locked = 1; return KMP_LOCK_ACQUIRED_FIRST; } } static int __kmp_acquire_nested_futex_lock_with_checks(kmp_futex_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_nest_lock"; if (!__kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_acquire_nested_futex_lock(lck, gtid); } int __kmp_test_nested_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) { int retval; KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_futex_lock_owner(lck) == gtid) { retval = ++lck->lk.depth_locked; } else if (!__kmp_test_futex_lock(lck, gtid)) { retval = 0; } else { KMP_MB(); retval = lck->lk.depth_locked = 1; } return retval; } static int __kmp_test_nested_futex_lock_with_checks(kmp_futex_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_nest_lock"; if (!__kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_test_nested_futex_lock(lck, gtid); } int __kmp_release_nested_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); KMP_MB(); if (--(lck->lk.depth_locked) == 0) { __kmp_release_futex_lock(lck, gtid); return KMP_LOCK_RELEASED; } return KMP_LOCK_STILL_HELD; } static int __kmp_release_nested_futex_lock_with_checks(kmp_futex_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_nest_lock"; KMP_MB(); /* in case another processor initialized lock */ if (!__kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_futex_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if (__kmp_get_futex_lock_owner(lck) != gtid) { KMP_FATAL(LockUnsettingSetByAnother, func); } return __kmp_release_nested_futex_lock(lck, gtid); } void __kmp_init_nested_futex_lock(kmp_futex_lock_t *lck) { __kmp_init_futex_lock(lck); lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks } void __kmp_destroy_nested_futex_lock(kmp_futex_lock_t *lck) { __kmp_destroy_futex_lock(lck); lck->lk.depth_locked = 0; } static void __kmp_destroy_nested_futex_lock_with_checks(kmp_futex_lock_t *lck) { char const *const func = "omp_destroy_nest_lock"; if (!__kmp_is_futex_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_futex_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_nested_futex_lock(lck); } #endif // KMP_USE_FUTEX /* ------------------------------------------------------------------------ */ /* ticket (bakery) locks */ static kmp_int32 __kmp_get_ticket_lock_owner(kmp_ticket_lock_t *lck) { return std::atomic_load_explicit(&lck->lk.owner_id, std::memory_order_relaxed) - 1; } static inline bool __kmp_is_ticket_lock_nestable(kmp_ticket_lock_t *lck) { return std::atomic_load_explicit(&lck->lk.depth_locked, std::memory_order_relaxed) != -1; } static kmp_uint32 __kmp_bakery_check(void *now_serving, kmp_uint32 my_ticket) { return std::atomic_load_explicit((std::atomic *)now_serving, std::memory_order_acquire) == my_ticket; } __forceinline static int __kmp_acquire_ticket_lock_timed_template(kmp_ticket_lock_t *lck, kmp_int32 gtid) { kmp_uint32 my_ticket = std::atomic_fetch_add_explicit( &lck->lk.next_ticket, 1U, std::memory_order_relaxed); #ifdef USE_LOCK_PROFILE if (std::atomic_load_explicit(&lck->lk.now_serving, std::memory_order_relaxed) != my_ticket) __kmp_printf("LOCK CONTENTION: %p\n", lck); /* else __kmp_printf( "." );*/ #endif /* USE_LOCK_PROFILE */ if (std::atomic_load_explicit(&lck->lk.now_serving, std::memory_order_acquire) == my_ticket) { return KMP_LOCK_ACQUIRED_FIRST; } KMP_WAIT_PTR(&lck->lk.now_serving, my_ticket, __kmp_bakery_check, lck); return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_acquire_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) { int retval = __kmp_acquire_ticket_lock_timed_template(lck, gtid); return retval; } static int __kmp_acquire_ticket_lock_with_checks(kmp_ticket_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if ((gtid >= 0) && (__kmp_get_ticket_lock_owner(lck) == gtid)) { KMP_FATAL(LockIsAlreadyOwned, func); } __kmp_acquire_ticket_lock(lck, gtid); std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1, std::memory_order_relaxed); return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_test_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) { kmp_uint32 my_ticket = std::atomic_load_explicit(&lck->lk.next_ticket, std::memory_order_relaxed); if (std::atomic_load_explicit(&lck->lk.now_serving, std::memory_order_relaxed) == my_ticket) { kmp_uint32 next_ticket = my_ticket + 1; if (std::atomic_compare_exchange_strong_explicit( &lck->lk.next_ticket, &my_ticket, next_ticket, std::memory_order_acquire, std::memory_order_acquire)) { return TRUE; } } return FALSE; } static int __kmp_test_ticket_lock_with_checks(kmp_ticket_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } int retval = __kmp_test_ticket_lock(lck, gtid); if (retval) { std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1, std::memory_order_relaxed); } return retval; } int __kmp_release_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) { kmp_uint32 distance = std::atomic_load_explicit(&lck->lk.next_ticket, std::memory_order_relaxed) - std::atomic_load_explicit(&lck->lk.now_serving, std::memory_order_relaxed); std::atomic_fetch_add_explicit(&lck->lk.now_serving, 1U, std::memory_order_release); KMP_YIELD(distance > (kmp_uint32)(__kmp_avail_proc ? __kmp_avail_proc : __kmp_xproc)); return KMP_LOCK_RELEASED; } static int __kmp_release_ticket_lock_with_checks(kmp_ticket_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_ticket_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if ((gtid >= 0) && (__kmp_get_ticket_lock_owner(lck) >= 0) && (__kmp_get_ticket_lock_owner(lck) != gtid)) { KMP_FATAL(LockUnsettingSetByAnother, func); } std::atomic_store_explicit(&lck->lk.owner_id, 0, std::memory_order_relaxed); return __kmp_release_ticket_lock(lck, gtid); } void __kmp_init_ticket_lock(kmp_ticket_lock_t *lck) { lck->lk.location = NULL; lck->lk.self = lck; std::atomic_store_explicit(&lck->lk.next_ticket, 0U, std::memory_order_relaxed); std::atomic_store_explicit(&lck->lk.now_serving, 0U, std::memory_order_relaxed); std::atomic_store_explicit( &lck->lk.owner_id, 0, std::memory_order_relaxed); // no thread owns the lock. std::atomic_store_explicit( &lck->lk.depth_locked, -1, std::memory_order_relaxed); // -1 => not a nested lock. std::atomic_store_explicit(&lck->lk.initialized, true, std::memory_order_release); } void __kmp_destroy_ticket_lock(kmp_ticket_lock_t *lck) { std::atomic_store_explicit(&lck->lk.initialized, false, std::memory_order_release); lck->lk.self = NULL; lck->lk.location = NULL; std::atomic_store_explicit(&lck->lk.next_ticket, 0U, std::memory_order_relaxed); std::atomic_store_explicit(&lck->lk.now_serving, 0U, std::memory_order_relaxed); std::atomic_store_explicit(&lck->lk.owner_id, 0, std::memory_order_relaxed); std::atomic_store_explicit(&lck->lk.depth_locked, -1, std::memory_order_relaxed); } static void __kmp_destroy_ticket_lock_with_checks(kmp_ticket_lock_t *lck) { char const *const func = "omp_destroy_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_ticket_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_ticket_lock(lck); } // nested ticket locks int __kmp_acquire_nested_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_ticket_lock_owner(lck) == gtid) { std::atomic_fetch_add_explicit(&lck->lk.depth_locked, 1, std::memory_order_relaxed); return KMP_LOCK_ACQUIRED_NEXT; } else { __kmp_acquire_ticket_lock_timed_template(lck, gtid); std::atomic_store_explicit(&lck->lk.depth_locked, 1, std::memory_order_relaxed); std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1, std::memory_order_relaxed); return KMP_LOCK_ACQUIRED_FIRST; } } static int __kmp_acquire_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_nest_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_acquire_nested_ticket_lock(lck, gtid); } int __kmp_test_nested_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) { int retval; KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_ticket_lock_owner(lck) == gtid) { retval = std::atomic_fetch_add_explicit(&lck->lk.depth_locked, 1, std::memory_order_relaxed) + 1; } else if (!__kmp_test_ticket_lock(lck, gtid)) { retval = 0; } else { std::atomic_store_explicit(&lck->lk.depth_locked, 1, std::memory_order_relaxed); std::atomic_store_explicit(&lck->lk.owner_id, gtid + 1, std::memory_order_relaxed); retval = 1; } return retval; } static int __kmp_test_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_nest_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_test_nested_ticket_lock(lck, gtid); } int __kmp_release_nested_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); if ((std::atomic_fetch_add_explicit(&lck->lk.depth_locked, -1, std::memory_order_relaxed) - 1) == 0) { std::atomic_store_explicit(&lck->lk.owner_id, 0, std::memory_order_relaxed); __kmp_release_ticket_lock(lck, gtid); return KMP_LOCK_RELEASED; } return KMP_LOCK_STILL_HELD; } static int __kmp_release_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_nest_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_ticket_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if (__kmp_get_ticket_lock_owner(lck) != gtid) { KMP_FATAL(LockUnsettingSetByAnother, func); } return __kmp_release_nested_ticket_lock(lck, gtid); } void __kmp_init_nested_ticket_lock(kmp_ticket_lock_t *lck) { __kmp_init_ticket_lock(lck); std::atomic_store_explicit(&lck->lk.depth_locked, 0, std::memory_order_relaxed); // >= 0 for nestable locks, -1 for simple locks } void __kmp_destroy_nested_ticket_lock(kmp_ticket_lock_t *lck) { __kmp_destroy_ticket_lock(lck); std::atomic_store_explicit(&lck->lk.depth_locked, 0, std::memory_order_relaxed); } static void __kmp_destroy_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck) { char const *const func = "omp_destroy_nest_lock"; if (!std::atomic_load_explicit(&lck->lk.initialized, std::memory_order_relaxed)) { KMP_FATAL(LockIsUninitialized, func); } if (lck->lk.self != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_ticket_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_ticket_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_nested_ticket_lock(lck); } // access functions to fields which don't exist for all lock kinds. static const ident_t *__kmp_get_ticket_lock_location(kmp_ticket_lock_t *lck) { return lck->lk.location; } static void __kmp_set_ticket_lock_location(kmp_ticket_lock_t *lck, const ident_t *loc) { lck->lk.location = loc; } static kmp_lock_flags_t __kmp_get_ticket_lock_flags(kmp_ticket_lock_t *lck) { return lck->lk.flags; } static void __kmp_set_ticket_lock_flags(kmp_ticket_lock_t *lck, kmp_lock_flags_t flags) { lck->lk.flags = flags; } /* ------------------------------------------------------------------------ */ /* queuing locks */ /* First the states (head,tail) = 0, 0 means lock is unheld, nobody on queue UINT_MAX or -1, 0 means lock is held, nobody on queue h, h means lock held or about to transition, 1 element on queue h, t h <> t, means lock is held or about to transition, >1 elements on queue Now the transitions Acquire(0,0) = -1 ,0 Release(0,0) = Error Acquire(-1,0) = h ,h h > 0 Release(-1,0) = 0 ,0 Acquire(h,h) = h ,t h > 0, t > 0, h <> t Release(h,h) = -1 ,0 h > 0 Acquire(h,t) = h ,t' h > 0, t > 0, t' > 0, h <> t, h <> t', t <> t' Release(h,t) = h',t h > 0, t > 0, h <> t, h <> h', h' maybe = t And pictorially +-----+ | 0, 0|------- release -------> Error +-----+ | ^ acquire| |release | | | | v | +-----+ |-1, 0| +-----+ | ^ acquire| |release | | | | v | +-----+ | h, h| +-----+ | ^ acquire| |release | | | | v | +-----+ | h, t|----- acquire, release loopback ---+ +-----+ | ^ | | | +------------------------------------+ */ #ifdef DEBUG_QUEUING_LOCKS /* Stuff for circular trace buffer */ #define TRACE_BUF_ELE 1024 static char traces[TRACE_BUF_ELE][128] = {0}; static int tc = 0; #define TRACE_LOCK(X, Y) \ KMP_SNPRINTF(traces[tc++ % TRACE_BUF_ELE], 128, "t%d at %s\n", X, Y); #define TRACE_LOCK_T(X, Y, Z) \ KMP_SNPRINTF(traces[tc++ % TRACE_BUF_ELE], 128, "t%d at %s%d\n", X, Y, Z); #define TRACE_LOCK_HT(X, Y, Z, Q) \ KMP_SNPRINTF(traces[tc++ % TRACE_BUF_ELE], 128, "t%d at %s %d,%d\n", X, Y, \ Z, Q); static void __kmp_dump_queuing_lock(kmp_info_t *this_thr, kmp_int32 gtid, kmp_queuing_lock_t *lck, kmp_int32 head_id, kmp_int32 tail_id) { kmp_int32 t, i; __kmp_printf_no_lock("\n__kmp_dump_queuing_lock: TRACE BEGINS HERE! \n"); i = tc % TRACE_BUF_ELE; __kmp_printf_no_lock("%s\n", traces[i]); i = (i + 1) % TRACE_BUF_ELE; while (i != (tc % TRACE_BUF_ELE)) { __kmp_printf_no_lock("%s", traces[i]); i = (i + 1) % TRACE_BUF_ELE; } __kmp_printf_no_lock("\n"); __kmp_printf_no_lock("\n__kmp_dump_queuing_lock: gtid+1:%d, spin_here:%d, " "next_wait:%d, head_id:%d, tail_id:%d\n", gtid + 1, this_thr->th.th_spin_here, this_thr->th.th_next_waiting, head_id, tail_id); __kmp_printf_no_lock("\t\thead: %d ", lck->lk.head_id); if (lck->lk.head_id >= 1) { t = __kmp_threads[lck->lk.head_id - 1]->th.th_next_waiting; while (t > 0) { __kmp_printf_no_lock("-> %d ", t); t = __kmp_threads[t - 1]->th.th_next_waiting; } } __kmp_printf_no_lock("; tail: %d ", lck->lk.tail_id); __kmp_printf_no_lock("\n\n"); } #endif /* DEBUG_QUEUING_LOCKS */ static kmp_int32 __kmp_get_queuing_lock_owner(kmp_queuing_lock_t *lck) { return TCR_4(lck->lk.owner_id) - 1; } static inline bool __kmp_is_queuing_lock_nestable(kmp_queuing_lock_t *lck) { return lck->lk.depth_locked != -1; } /* Acquire a lock using a the queuing lock implementation */ template /* [TLW] The unused template above is left behind because of what BEB believes is a potential compiler problem with __forceinline. */ __forceinline static int __kmp_acquire_queuing_lock_timed_template(kmp_queuing_lock_t *lck, kmp_int32 gtid) { kmp_info_t *this_thr = __kmp_thread_from_gtid(gtid); volatile kmp_int32 *head_id_p = &lck->lk.head_id; volatile kmp_int32 *tail_id_p = &lck->lk.tail_id; volatile kmp_uint32 *spin_here_p; #if OMPT_SUPPORT ompt_state_t prev_state = ompt_state_undefined; #endif KA_TRACE(1000, ("__kmp_acquire_queuing_lock: lck:%p, T#%d entering\n", lck, gtid)); KMP_FSYNC_PREPARE(lck); KMP_DEBUG_ASSERT(this_thr != NULL); spin_here_p = &this_thr->th.th_spin_here; #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "acq ent"); if (*spin_here_p) __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p); if (this_thr->th.th_next_waiting != 0) __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p); #endif KMP_DEBUG_ASSERT(!*spin_here_p); KMP_DEBUG_ASSERT(this_thr->th.th_next_waiting == 0); /* The following st.rel to spin_here_p needs to precede the cmpxchg.acq to head_id_p that may follow, not just in execution order, but also in visibility order. This way, when a releasing thread observes the changes to the queue by this thread, it can rightly assume that spin_here_p has already been set to TRUE, so that when it sets spin_here_p to FALSE, it is not premature. If the releasing thread sets spin_here_p to FALSE before this thread sets it to TRUE, this thread will hang. */ *spin_here_p = TRUE; /* before enqueuing to prevent race */ while (1) { kmp_int32 enqueued; kmp_int32 head; kmp_int32 tail; head = *head_id_p; switch (head) { case -1: { #ifdef DEBUG_QUEUING_LOCKS tail = *tail_id_p; TRACE_LOCK_HT(gtid + 1, "acq read: ", head, tail); #endif tail = 0; /* to make sure next link asynchronously read is not set accidentally; this assignment prevents us from entering the if ( t > 0 ) condition in the enqueued case below, which is not necessary for this state transition */ /* try (-1,0)->(tid,tid) */ enqueued = KMP_COMPARE_AND_STORE_ACQ64((volatile kmp_int64 *)tail_id_p, KMP_PACK_64(-1, 0), KMP_PACK_64(gtid + 1, gtid + 1)); #ifdef DEBUG_QUEUING_LOCKS if (enqueued) TRACE_LOCK(gtid + 1, "acq enq: (-1,0)->(tid,tid)"); #endif } break; default: { tail = *tail_id_p; KMP_DEBUG_ASSERT(tail != gtid + 1); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK_HT(gtid + 1, "acq read: ", head, tail); #endif if (tail == 0) { enqueued = FALSE; } else { /* try (h,t) or (h,h)->(h,tid) */ enqueued = KMP_COMPARE_AND_STORE_ACQ32(tail_id_p, tail, gtid + 1); #ifdef DEBUG_QUEUING_LOCKS if (enqueued) TRACE_LOCK(gtid + 1, "acq enq: (h,t)->(h,tid)"); #endif } } break; case 0: /* empty queue */ { kmp_int32 grabbed_lock; #ifdef DEBUG_QUEUING_LOCKS tail = *tail_id_p; TRACE_LOCK_HT(gtid + 1, "acq read: ", head, tail); #endif /* try (0,0)->(-1,0) */ /* only legal transition out of head = 0 is head = -1 with no change to * tail */ grabbed_lock = KMP_COMPARE_AND_STORE_ACQ32(head_id_p, 0, -1); if (grabbed_lock) { *spin_here_p = FALSE; KA_TRACE( 1000, ("__kmp_acquire_queuing_lock: lck:%p, T#%d exiting: no queuing\n", lck, gtid)); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK_HT(gtid + 1, "acq exit: ", head, 0); #endif #if OMPT_SUPPORT if (ompt_enabled.enabled && prev_state != ompt_state_undefined) { /* change the state before clearing wait_id */ this_thr->th.ompt_thread_info.state = prev_state; this_thr->th.ompt_thread_info.wait_id = 0; } #endif KMP_FSYNC_ACQUIRED(lck); return KMP_LOCK_ACQUIRED_FIRST; /* lock holder cannot be on queue */ } enqueued = FALSE; } break; } #if OMPT_SUPPORT if (ompt_enabled.enabled && prev_state == ompt_state_undefined) { /* this thread will spin; set wait_id before entering wait state */ prev_state = this_thr->th.ompt_thread_info.state; this_thr->th.ompt_thread_info.wait_id = (uint64_t)lck; this_thr->th.ompt_thread_info.state = ompt_state_wait_lock; } #endif if (enqueued) { if (tail > 0) { kmp_info_t *tail_thr = __kmp_thread_from_gtid(tail - 1); KMP_ASSERT(tail_thr != NULL); tail_thr->th.th_next_waiting = gtid + 1; /* corresponding wait for this write in release code */ } KA_TRACE(1000, ("__kmp_acquire_queuing_lock: lck:%p, T#%d waiting for lock\n", lck, gtid)); KMP_MB(); // ToDo: Use __kmp_wait_sleep or similar when blocktime != inf KMP_WAIT(spin_here_p, FALSE, KMP_EQ, lck); // Synchronize writes to both runtime thread structures // and writes in user code. KMP_MB(); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "acq spin"); if (this_thr->th.th_next_waiting != 0) __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p); #endif KMP_DEBUG_ASSERT(this_thr->th.th_next_waiting == 0); KA_TRACE(1000, ("__kmp_acquire_queuing_lock: lck:%p, T#%d exiting: after " "waiting on queue\n", lck, gtid)); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "acq exit 2"); #endif #if OMPT_SUPPORT /* change the state before clearing wait_id */ this_thr->th.ompt_thread_info.state = prev_state; this_thr->th.ompt_thread_info.wait_id = 0; #endif /* got lock, we were dequeued by the thread that released lock */ return KMP_LOCK_ACQUIRED_FIRST; } /* Yield if number of threads > number of logical processors */ /* ToDo: Not sure why this should only be in oversubscription case, maybe should be traditional YIELD_INIT/YIELD_WHEN loop */ KMP_YIELD_OVERSUB(); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "acq retry"); #endif } KMP_ASSERT2(0, "should not get here"); return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_acquire_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); int retval = __kmp_acquire_queuing_lock_timed_template(lck, gtid); return retval; } static int __kmp_acquire_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_queuing_lock_owner(lck) == gtid) { KMP_FATAL(LockIsAlreadyOwned, func); } __kmp_acquire_queuing_lock(lck, gtid); lck->lk.owner_id = gtid + 1; return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_test_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { volatile kmp_int32 *head_id_p = &lck->lk.head_id; kmp_int32 head; #ifdef KMP_DEBUG kmp_info_t *this_thr; #endif KA_TRACE(1000, ("__kmp_test_queuing_lock: T#%d entering\n", gtid)); KMP_DEBUG_ASSERT(gtid >= 0); #ifdef KMP_DEBUG this_thr = __kmp_thread_from_gtid(gtid); KMP_DEBUG_ASSERT(this_thr != NULL); KMP_DEBUG_ASSERT(!this_thr->th.th_spin_here); #endif head = *head_id_p; if (head == 0) { /* nobody on queue, nobody holding */ /* try (0,0)->(-1,0) */ if (KMP_COMPARE_AND_STORE_ACQ32(head_id_p, 0, -1)) { KA_TRACE(1000, ("__kmp_test_queuing_lock: T#%d exiting: holding lock\n", gtid)); KMP_FSYNC_ACQUIRED(lck); return TRUE; } } KA_TRACE(1000, ("__kmp_test_queuing_lock: T#%d exiting: without lock\n", gtid)); return FALSE; } static int __kmp_test_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } int retval = __kmp_test_queuing_lock(lck, gtid); if (retval) { lck->lk.owner_id = gtid + 1; } return retval; } int __kmp_release_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { volatile kmp_int32 *head_id_p = &lck->lk.head_id; volatile kmp_int32 *tail_id_p = &lck->lk.tail_id; KA_TRACE(1000, ("__kmp_release_queuing_lock: lck:%p, T#%d entering\n", lck, gtid)); KMP_DEBUG_ASSERT(gtid >= 0); #if KMP_DEBUG || DEBUG_QUEUING_LOCKS kmp_info_t *this_thr = __kmp_thread_from_gtid(gtid); #endif KMP_DEBUG_ASSERT(this_thr != NULL); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "rel ent"); if (this_thr->th.th_spin_here) __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p); if (this_thr->th.th_next_waiting != 0) __kmp_dump_queuing_lock(this_thr, gtid, lck, *head_id_p, *tail_id_p); #endif KMP_DEBUG_ASSERT(!this_thr->th.th_spin_here); KMP_DEBUG_ASSERT(this_thr->th.th_next_waiting == 0); KMP_FSYNC_RELEASING(lck); while (1) { kmp_int32 dequeued; kmp_int32 head; kmp_int32 tail; head = *head_id_p; #ifdef DEBUG_QUEUING_LOCKS tail = *tail_id_p; TRACE_LOCK_HT(gtid + 1, "rel read: ", head, tail); if (head == 0) __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail); #endif KMP_DEBUG_ASSERT(head != 0); /* holding the lock, head must be -1 or queue head */ if (head == -1) { /* nobody on queue */ /* try (-1,0)->(0,0) */ if (KMP_COMPARE_AND_STORE_REL32(head_id_p, -1, 0)) { KA_TRACE( 1000, ("__kmp_release_queuing_lock: lck:%p, T#%d exiting: queue empty\n", lck, gtid)); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK_HT(gtid + 1, "rel exit: ", 0, 0); #endif #if OMPT_SUPPORT /* nothing to do - no other thread is trying to shift blame */ #endif return KMP_LOCK_RELEASED; } dequeued = FALSE; } else { KMP_MB(); tail = *tail_id_p; if (head == tail) { /* only one thread on the queue */ #ifdef DEBUG_QUEUING_LOCKS if (head <= 0) __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail); #endif KMP_DEBUG_ASSERT(head > 0); /* try (h,h)->(-1,0) */ dequeued = KMP_COMPARE_AND_STORE_REL64( RCAST(volatile kmp_int64 *, tail_id_p), KMP_PACK_64(head, head), KMP_PACK_64(-1, 0)); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "rel deq: (h,h)->(-1,0)"); #endif } else { volatile kmp_int32 *waiting_id_p; kmp_info_t *head_thr = __kmp_thread_from_gtid(head - 1); KMP_DEBUG_ASSERT(head_thr != NULL); waiting_id_p = &head_thr->th.th_next_waiting; /* Does this require synchronous reads? */ #ifdef DEBUG_QUEUING_LOCKS if (head <= 0 || tail <= 0) __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail); #endif KMP_DEBUG_ASSERT(head > 0 && tail > 0); /* try (h,t)->(h',t) or (t,t) */ KMP_MB(); /* make sure enqueuing thread has time to update next waiting thread * field */ *head_id_p = KMP_WAIT((volatile kmp_uint32 *)waiting_id_p, 0, KMP_NEQ, NULL); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "rel deq: (h,t)->(h',t)"); #endif dequeued = TRUE; } } if (dequeued) { kmp_info_t *head_thr = __kmp_thread_from_gtid(head - 1); KMP_DEBUG_ASSERT(head_thr != NULL); /* Does this require synchronous reads? */ #ifdef DEBUG_QUEUING_LOCKS if (head <= 0 || tail <= 0) __kmp_dump_queuing_lock(this_thr, gtid, lck, head, tail); #endif KMP_DEBUG_ASSERT(head > 0 && tail > 0); /* For clean code only. Thread not released until next statement prevents race with acquire code. */ head_thr->th.th_next_waiting = 0; #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK_T(gtid + 1, "rel nw=0 for t=", head); #endif KMP_MB(); /* reset spin value */ head_thr->th.th_spin_here = FALSE; KA_TRACE(1000, ("__kmp_release_queuing_lock: lck:%p, T#%d exiting: after " "dequeuing\n", lck, gtid)); #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "rel exit 2"); #endif return KMP_LOCK_RELEASED; } /* KMP_CPU_PAUSE(); don't want to make releasing thread hold up acquiring threads */ #ifdef DEBUG_QUEUING_LOCKS TRACE_LOCK(gtid + 1, "rel retry"); #endif } /* while */ KMP_ASSERT2(0, "should not get here"); return KMP_LOCK_RELEASED; } static int __kmp_release_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_lock"; KMP_MB(); /* in case another processor initialized lock */ if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_queuing_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if (__kmp_get_queuing_lock_owner(lck) != gtid) { KMP_FATAL(LockUnsettingSetByAnother, func); } lck->lk.owner_id = 0; return __kmp_release_queuing_lock(lck, gtid); } void __kmp_init_queuing_lock(kmp_queuing_lock_t *lck) { lck->lk.location = NULL; lck->lk.head_id = 0; lck->lk.tail_id = 0; lck->lk.next_ticket = 0; lck->lk.now_serving = 0; lck->lk.owner_id = 0; // no thread owns the lock. lck->lk.depth_locked = -1; // >= 0 for nestable locks, -1 for simple locks. lck->lk.initialized = lck; KA_TRACE(1000, ("__kmp_init_queuing_lock: lock %p initialized\n", lck)); } void __kmp_destroy_queuing_lock(kmp_queuing_lock_t *lck) { lck->lk.initialized = NULL; lck->lk.location = NULL; lck->lk.head_id = 0; lck->lk.tail_id = 0; lck->lk.next_ticket = 0; lck->lk.now_serving = 0; lck->lk.owner_id = 0; lck->lk.depth_locked = -1; } static void __kmp_destroy_queuing_lock_with_checks(kmp_queuing_lock_t *lck) { char const *const func = "omp_destroy_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_queuing_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_queuing_lock(lck); } // nested queuing locks int __kmp_acquire_nested_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_queuing_lock_owner(lck) == gtid) { lck->lk.depth_locked += 1; return KMP_LOCK_ACQUIRED_NEXT; } else { __kmp_acquire_queuing_lock_timed_template(lck, gtid); KMP_MB(); lck->lk.depth_locked = 1; KMP_MB(); lck->lk.owner_id = gtid + 1; return KMP_LOCK_ACQUIRED_FIRST; } } static int __kmp_acquire_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_nest_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_acquire_nested_queuing_lock(lck, gtid); } int __kmp_test_nested_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { int retval; KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_queuing_lock_owner(lck) == gtid) { retval = ++lck->lk.depth_locked; } else if (!__kmp_test_queuing_lock(lck, gtid)) { retval = 0; } else { KMP_MB(); retval = lck->lk.depth_locked = 1; KMP_MB(); lck->lk.owner_id = gtid + 1; } return retval; } static int __kmp_test_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_nest_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_test_nested_queuing_lock(lck, gtid); } int __kmp_release_nested_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); KMP_MB(); if (--(lck->lk.depth_locked) == 0) { KMP_MB(); lck->lk.owner_id = 0; __kmp_release_queuing_lock(lck, gtid); return KMP_LOCK_RELEASED; } return KMP_LOCK_STILL_HELD; } static int __kmp_release_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_nest_lock"; KMP_MB(); /* in case another processor initialized lock */ if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_queuing_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if (__kmp_get_queuing_lock_owner(lck) != gtid) { KMP_FATAL(LockUnsettingSetByAnother, func); } return __kmp_release_nested_queuing_lock(lck, gtid); } void __kmp_init_nested_queuing_lock(kmp_queuing_lock_t *lck) { __kmp_init_queuing_lock(lck); lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks } void __kmp_destroy_nested_queuing_lock(kmp_queuing_lock_t *lck) { __kmp_destroy_queuing_lock(lck); lck->lk.depth_locked = 0; } static void __kmp_destroy_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck) { char const *const func = "omp_destroy_nest_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_queuing_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_queuing_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_nested_queuing_lock(lck); } // access functions to fields which don't exist for all lock kinds. static const ident_t *__kmp_get_queuing_lock_location(kmp_queuing_lock_t *lck) { return lck->lk.location; } static void __kmp_set_queuing_lock_location(kmp_queuing_lock_t *lck, const ident_t *loc) { lck->lk.location = loc; } static kmp_lock_flags_t __kmp_get_queuing_lock_flags(kmp_queuing_lock_t *lck) { return lck->lk.flags; } static void __kmp_set_queuing_lock_flags(kmp_queuing_lock_t *lck, kmp_lock_flags_t flags) { lck->lk.flags = flags; } #if KMP_USE_ADAPTIVE_LOCKS /* RTM Adaptive locks */ #if KMP_HAVE_RTM_INTRINSICS #include #define SOFT_ABORT_MASK (_XABORT_RETRY | _XABORT_CONFLICT | _XABORT_EXPLICIT) #else // Values from the status register after failed speculation. #define _XBEGIN_STARTED (~0u) #define _XABORT_EXPLICIT (1 << 0) #define _XABORT_RETRY (1 << 1) #define _XABORT_CONFLICT (1 << 2) #define _XABORT_CAPACITY (1 << 3) #define _XABORT_DEBUG (1 << 4) #define _XABORT_NESTED (1 << 5) #define _XABORT_CODE(x) ((unsigned char)(((x) >> 24) & 0xFF)) // Aborts for which it's worth trying again immediately #define SOFT_ABORT_MASK (_XABORT_RETRY | _XABORT_CONFLICT | _XABORT_EXPLICIT) #define STRINGIZE_INTERNAL(arg) #arg #define STRINGIZE(arg) STRINGIZE_INTERNAL(arg) // Access to RTM instructions /*A version of XBegin which returns -1 on speculation, and the value of EAX on an abort. This is the same definition as the compiler intrinsic that will be supported at some point. */ static __inline int _xbegin() { int res = -1; #if KMP_OS_WINDOWS #if KMP_ARCH_X86_64 _asm { _emit 0xC7 _emit 0xF8 _emit 2 _emit 0 _emit 0 _emit 0 jmp L2 mov res, eax L2: } #else /* IA32 */ _asm { _emit 0xC7 _emit 0xF8 _emit 2 _emit 0 _emit 0 _emit 0 jmp L2 mov res, eax L2: } #endif // KMP_ARCH_X86_64 #else /* Note that %eax must be noted as killed (clobbered), because the XSR is returned in %eax(%rax) on abort. Other register values are restored, so don't need to be killed. We must also mark 'res' as an input and an output, since otherwise 'res=-1' may be dropped as being dead, whereas we do need the assignment on the successful (i.e., non-abort) path. */ __asm__ volatile("1: .byte 0xC7; .byte 0xF8;\n" " .long 1f-1b-6\n" " jmp 2f\n" "1: movl %%eax,%0\n" "2:" : "+r"(res)::"memory", "%eax"); #endif // KMP_OS_WINDOWS return res; } /* Transaction end */ static __inline void _xend() { #if KMP_OS_WINDOWS __asm { _emit 0x0f _emit 0x01 _emit 0xd5 } #else __asm__ volatile(".byte 0x0f; .byte 0x01; .byte 0xd5" ::: "memory"); #endif } /* This is a macro, the argument must be a single byte constant which can be evaluated by the inline assembler, since it is emitted as a byte into the assembly code. */ // clang-format off #if KMP_OS_WINDOWS #define _xabort(ARG) _asm _emit 0xc6 _asm _emit 0xf8 _asm _emit ARG #else #define _xabort(ARG) \ __asm__ volatile(".byte 0xC6; .byte 0xF8; .byte " STRINGIZE(ARG):::"memory"); #endif // clang-format on #endif // KMP_COMPILER_ICC && __INTEL_COMPILER >= 1300 // Statistics is collected for testing purpose #if KMP_DEBUG_ADAPTIVE_LOCKS // We accumulate speculative lock statistics when the lock is destroyed. We // keep locks that haven't been destroyed in the liveLocks list so that we can // grab their statistics too. static kmp_adaptive_lock_statistics_t destroyedStats; // To hold the list of live locks. static kmp_adaptive_lock_info_t liveLocks; // A lock so we can safely update the list of locks. static kmp_bootstrap_lock_t chain_lock = KMP_BOOTSTRAP_LOCK_INITIALIZER(chain_lock); // Initialize the list of stats. void __kmp_init_speculative_stats() { kmp_adaptive_lock_info_t *lck = &liveLocks; memset(CCAST(kmp_adaptive_lock_statistics_t *, &(lck->stats)), 0, sizeof(lck->stats)); lck->stats.next = lck; lck->stats.prev = lck; KMP_ASSERT(lck->stats.next->stats.prev == lck); KMP_ASSERT(lck->stats.prev->stats.next == lck); __kmp_init_bootstrap_lock(&chain_lock); } // Insert the lock into the circular list static void __kmp_remember_lock(kmp_adaptive_lock_info_t *lck) { __kmp_acquire_bootstrap_lock(&chain_lock); lck->stats.next = liveLocks.stats.next; lck->stats.prev = &liveLocks; liveLocks.stats.next = lck; lck->stats.next->stats.prev = lck; KMP_ASSERT(lck->stats.next->stats.prev == lck); KMP_ASSERT(lck->stats.prev->stats.next == lck); __kmp_release_bootstrap_lock(&chain_lock); } static void __kmp_forget_lock(kmp_adaptive_lock_info_t *lck) { KMP_ASSERT(lck->stats.next->stats.prev == lck); KMP_ASSERT(lck->stats.prev->stats.next == lck); kmp_adaptive_lock_info_t *n = lck->stats.next; kmp_adaptive_lock_info_t *p = lck->stats.prev; n->stats.prev = p; p->stats.next = n; } static void __kmp_zero_speculative_stats(kmp_adaptive_lock_info_t *lck) { memset(CCAST(kmp_adaptive_lock_statistics_t *, &lck->stats), 0, sizeof(lck->stats)); __kmp_remember_lock(lck); } static void __kmp_add_stats(kmp_adaptive_lock_statistics_t *t, kmp_adaptive_lock_info_t *lck) { kmp_adaptive_lock_statistics_t volatile *s = &lck->stats; t->nonSpeculativeAcquireAttempts += lck->acquire_attempts; t->successfulSpeculations += s->successfulSpeculations; t->hardFailedSpeculations += s->hardFailedSpeculations; t->softFailedSpeculations += s->softFailedSpeculations; t->nonSpeculativeAcquires += s->nonSpeculativeAcquires; t->lemmingYields += s->lemmingYields; } static void __kmp_accumulate_speculative_stats(kmp_adaptive_lock_info_t *lck) { __kmp_acquire_bootstrap_lock(&chain_lock); __kmp_add_stats(&destroyedStats, lck); __kmp_forget_lock(lck); __kmp_release_bootstrap_lock(&chain_lock); } static float percent(kmp_uint32 count, kmp_uint32 total) { return (total == 0) ? 0.0 : (100.0 * count) / total; } void __kmp_print_speculative_stats() { kmp_adaptive_lock_statistics_t total = destroyedStats; kmp_adaptive_lock_info_t *lck; for (lck = liveLocks.stats.next; lck != &liveLocks; lck = lck->stats.next) { __kmp_add_stats(&total, lck); } kmp_adaptive_lock_statistics_t *t = &total; kmp_uint32 totalSections = t->nonSpeculativeAcquires + t->successfulSpeculations; kmp_uint32 totalSpeculations = t->successfulSpeculations + t->hardFailedSpeculations + t->softFailedSpeculations; if (totalSections <= 0) return; kmp_safe_raii_file_t statsFile; if (strcmp(__kmp_speculative_statsfile, "-") == 0) { statsFile.set_stdout(); } else { size_t buffLen = KMP_STRLEN(__kmp_speculative_statsfile) + 20; char buffer[buffLen]; KMP_SNPRINTF(&buffer[0], buffLen, __kmp_speculative_statsfile, (kmp_int32)getpid()); statsFile.open(buffer, "w"); } fprintf(statsFile, "Speculative lock statistics (all approximate!)\n"); fprintf(statsFile, " Lock parameters: \n" " max_soft_retries : %10d\n" " max_badness : %10d\n", __kmp_adaptive_backoff_params.max_soft_retries, __kmp_adaptive_backoff_params.max_badness); fprintf(statsFile, " Non-speculative acquire attempts : %10d\n", t->nonSpeculativeAcquireAttempts); fprintf(statsFile, " Total critical sections : %10d\n", totalSections); fprintf(statsFile, " Successful speculations : %10d (%5.1f%%)\n", t->successfulSpeculations, percent(t->successfulSpeculations, totalSections)); fprintf(statsFile, " Non-speculative acquires : %10d (%5.1f%%)\n", t->nonSpeculativeAcquires, percent(t->nonSpeculativeAcquires, totalSections)); fprintf(statsFile, " Lemming yields : %10d\n\n", t->lemmingYields); fprintf(statsFile, " Speculative acquire attempts : %10d\n", totalSpeculations); fprintf(statsFile, " Successes : %10d (%5.1f%%)\n", t->successfulSpeculations, percent(t->successfulSpeculations, totalSpeculations)); fprintf(statsFile, " Soft failures : %10d (%5.1f%%)\n", t->softFailedSpeculations, percent(t->softFailedSpeculations, totalSpeculations)); fprintf(statsFile, " Hard failures : %10d (%5.1f%%)\n", t->hardFailedSpeculations, percent(t->hardFailedSpeculations, totalSpeculations)); } #define KMP_INC_STAT(lck, stat) (lck->lk.adaptive.stats.stat++) #else #define KMP_INC_STAT(lck, stat) #endif // KMP_DEBUG_ADAPTIVE_LOCKS static inline bool __kmp_is_unlocked_queuing_lock(kmp_queuing_lock_t *lck) { // It is enough to check that the head_id is zero. // We don't also need to check the tail. bool res = lck->lk.head_id == 0; // We need a fence here, since we must ensure that no memory operations // from later in this thread float above that read. #if KMP_COMPILER_ICC || KMP_COMPILER_ICX _mm_mfence(); #else __sync_synchronize(); #endif return res; } // Functions for manipulating the badness static __inline void __kmp_update_badness_after_success(kmp_adaptive_lock_t *lck) { // Reset the badness to zero so we eagerly try to speculate again lck->lk.adaptive.badness = 0; KMP_INC_STAT(lck, successfulSpeculations); } // Create a bit mask with one more set bit. static __inline void __kmp_step_badness(kmp_adaptive_lock_t *lck) { kmp_uint32 newBadness = (lck->lk.adaptive.badness << 1) | 1; if (newBadness > lck->lk.adaptive.max_badness) { return; } else { lck->lk.adaptive.badness = newBadness; } } // Check whether speculation should be attempted. KMP_ATTRIBUTE_TARGET_RTM static __inline int __kmp_should_speculate(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { kmp_uint32 badness = lck->lk.adaptive.badness; kmp_uint32 attempts = lck->lk.adaptive.acquire_attempts; int res = (attempts & badness) == 0; return res; } // Attempt to acquire only the speculative lock. // Does not back off to the non-speculative lock. KMP_ATTRIBUTE_TARGET_RTM static int __kmp_test_adaptive_lock_only(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { int retries = lck->lk.adaptive.max_soft_retries; // We don't explicitly count the start of speculation, rather we record the // results (success, hard fail, soft fail). The sum of all of those is the // total number of times we started speculation since all speculations must // end one of those ways. do { kmp_uint32 status = _xbegin(); // Switch this in to disable actual speculation but exercise at least some // of the rest of the code. Useful for debugging... // kmp_uint32 status = _XABORT_NESTED; if (status == _XBEGIN_STARTED) { /* We have successfully started speculation. Check that no-one acquired the lock for real between when we last looked and now. This also gets the lock cache line into our read-set, which we need so that we'll abort if anyone later claims it for real. */ if (!__kmp_is_unlocked_queuing_lock(GET_QLK_PTR(lck))) { // Lock is now visibly acquired, so someone beat us to it. Abort the // transaction so we'll restart from _xbegin with the failure status. _xabort(0x01); KMP_ASSERT2(0, "should not get here"); } return 1; // Lock has been acquired (speculatively) } else { // We have aborted, update the statistics if (status & SOFT_ABORT_MASK) { KMP_INC_STAT(lck, softFailedSpeculations); // and loop round to retry. } else { KMP_INC_STAT(lck, hardFailedSpeculations); // Give up if we had a hard failure. break; } } } while (retries--); // Loop while we have retries, and didn't fail hard. // Either we had a hard failure or we didn't succeed softly after // the full set of attempts, so back off the badness. __kmp_step_badness(lck); return 0; } // Attempt to acquire the speculative lock, or back off to the non-speculative // one if the speculative lock cannot be acquired. // We can succeed speculatively, non-speculatively, or fail. static int __kmp_test_adaptive_lock(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { // First try to acquire the lock speculatively if (__kmp_should_speculate(lck, gtid) && __kmp_test_adaptive_lock_only(lck, gtid)) return 1; // Speculative acquisition failed, so try to acquire it non-speculatively. // Count the non-speculative acquire attempt lck->lk.adaptive.acquire_attempts++; // Use base, non-speculative lock. if (__kmp_test_queuing_lock(GET_QLK_PTR(lck), gtid)) { KMP_INC_STAT(lck, nonSpeculativeAcquires); return 1; // Lock is acquired (non-speculatively) } else { return 0; // Failed to acquire the lock, it's already visibly locked. } } static int __kmp_test_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_lock"; if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) { KMP_FATAL(LockIsUninitialized, func); } int retval = __kmp_test_adaptive_lock(lck, gtid); if (retval) { lck->lk.qlk.owner_id = gtid + 1; } return retval; } // Block until we can acquire a speculative, adaptive lock. We check whether we // should be trying to speculate. If we should be, we check the real lock to see // if it is free, and, if not, pause without attempting to acquire it until it // is. Then we try the speculative acquire. This means that although we suffer // from lemmings a little (because all we can't acquire the lock speculatively // until the queue of threads waiting has cleared), we don't get into a state // where we can never acquire the lock speculatively (because we force the queue // to clear by preventing new arrivals from entering the queue). This does mean // that when we're trying to break lemmings, the lock is no longer fair. However // OpenMP makes no guarantee that its locks are fair, so this isn't a real // problem. static void __kmp_acquire_adaptive_lock(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { if (__kmp_should_speculate(lck, gtid)) { if (__kmp_is_unlocked_queuing_lock(GET_QLK_PTR(lck))) { if (__kmp_test_adaptive_lock_only(lck, gtid)) return; // We tried speculation and failed, so give up. } else { // We can't try speculation until the lock is free, so we pause here // (without suspending on the queueing lock, to allow it to drain, then // try again. All other threads will also see the same result for // shouldSpeculate, so will be doing the same if they try to claim the // lock from now on. while (!__kmp_is_unlocked_queuing_lock(GET_QLK_PTR(lck))) { KMP_INC_STAT(lck, lemmingYields); KMP_YIELD(TRUE); } if (__kmp_test_adaptive_lock_only(lck, gtid)) return; } } // Speculative acquisition failed, so acquire it non-speculatively. // Count the non-speculative acquire attempt lck->lk.adaptive.acquire_attempts++; __kmp_acquire_queuing_lock_timed_template(GET_QLK_PTR(lck), gtid); // We have acquired the base lock, so count that. KMP_INC_STAT(lck, nonSpeculativeAcquires); } static void __kmp_acquire_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_lock"; if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) == gtid) { KMP_FATAL(LockIsAlreadyOwned, func); } __kmp_acquire_adaptive_lock(lck, gtid); lck->lk.qlk.owner_id = gtid + 1; } KMP_ATTRIBUTE_TARGET_RTM static int __kmp_release_adaptive_lock(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { if (__kmp_is_unlocked_queuing_lock(GET_QLK_PTR( lck))) { // If the lock doesn't look claimed we must be speculating. // (Or the user's code is buggy and they're releasing without locking; // if we had XTEST we'd be able to check that case...) _xend(); // Exit speculation __kmp_update_badness_after_success(lck); } else { // Since the lock *is* visibly locked we're not speculating, // so should use the underlying lock's release scheme. __kmp_release_queuing_lock(GET_QLK_PTR(lck), gtid); } return KMP_LOCK_RELEASED; } static int __kmp_release_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_lock"; KMP_MB(); /* in case another processor initialized lock */ if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) == -1) { KMP_FATAL(LockUnsettingFree, func); } if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) != gtid) { KMP_FATAL(LockUnsettingSetByAnother, func); } lck->lk.qlk.owner_id = 0; __kmp_release_adaptive_lock(lck, gtid); return KMP_LOCK_RELEASED; } static void __kmp_init_adaptive_lock(kmp_adaptive_lock_t *lck) { __kmp_init_queuing_lock(GET_QLK_PTR(lck)); lck->lk.adaptive.badness = 0; lck->lk.adaptive.acquire_attempts = 0; // nonSpeculativeAcquireAttempts = 0; lck->lk.adaptive.max_soft_retries = __kmp_adaptive_backoff_params.max_soft_retries; lck->lk.adaptive.max_badness = __kmp_adaptive_backoff_params.max_badness; #if KMP_DEBUG_ADAPTIVE_LOCKS __kmp_zero_speculative_stats(&lck->lk.adaptive); #endif KA_TRACE(1000, ("__kmp_init_adaptive_lock: lock %p initialized\n", lck)); } static void __kmp_destroy_adaptive_lock(kmp_adaptive_lock_t *lck) { #if KMP_DEBUG_ADAPTIVE_LOCKS __kmp_accumulate_speculative_stats(&lck->lk.adaptive); #endif __kmp_destroy_queuing_lock(GET_QLK_PTR(lck)); // Nothing needed for the speculative part. } static void __kmp_destroy_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck) { char const *const func = "omp_destroy_lock"; if (lck->lk.qlk.initialized != GET_QLK_PTR(lck)) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_get_queuing_lock_owner(GET_QLK_PTR(lck)) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_adaptive_lock(lck); } #endif // KMP_USE_ADAPTIVE_LOCKS /* ------------------------------------------------------------------------ */ /* DRDPA ticket locks */ /* "DRDPA" means Dynamically Reconfigurable Distributed Polling Area */ static kmp_int32 __kmp_get_drdpa_lock_owner(kmp_drdpa_lock_t *lck) { return lck->lk.owner_id - 1; } static inline bool __kmp_is_drdpa_lock_nestable(kmp_drdpa_lock_t *lck) { return lck->lk.depth_locked != -1; } __forceinline static int __kmp_acquire_drdpa_lock_timed_template(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { kmp_uint64 ticket = KMP_ATOMIC_INC(&lck->lk.next_ticket); kmp_uint64 mask = lck->lk.mask; // atomic load std::atomic *polls = lck->lk.polls; #ifdef USE_LOCK_PROFILE if (polls[ticket & mask] != ticket) __kmp_printf("LOCK CONTENTION: %p\n", lck); /* else __kmp_printf( "." );*/ #endif /* USE_LOCK_PROFILE */ // Now spin-wait, but reload the polls pointer and mask, in case the // polling area has been reconfigured. Unless it is reconfigured, the // reloads stay in L1 cache and are cheap. // // Keep this code in sync with KMP_WAIT, in kmp_dispatch.cpp !!! // The current implementation of KMP_WAIT doesn't allow for mask // and poll to be re-read every spin iteration. kmp_uint32 spins; kmp_uint64 time; KMP_FSYNC_PREPARE(lck); KMP_INIT_YIELD(spins); KMP_INIT_BACKOFF(time); while (polls[ticket & mask] < ticket) { // atomic load KMP_YIELD_OVERSUB_ELSE_SPIN(spins, time); // Re-read the mask and the poll pointer from the lock structure. // // Make certain that "mask" is read before "polls" !!! // // If another thread picks reconfigures the polling area and updates their // values, and we get the new value of mask and the old polls pointer, we // could access memory beyond the end of the old polling area. mask = lck->lk.mask; // atomic load polls = lck->lk.polls; // atomic load } // Critical section starts here KMP_FSYNC_ACQUIRED(lck); KA_TRACE(1000, ("__kmp_acquire_drdpa_lock: ticket #%lld acquired lock %p\n", ticket, lck)); lck->lk.now_serving = ticket; // non-volatile store // Deallocate a garbage polling area if we know that we are the last // thread that could possibly access it. // // The >= check is in case __kmp_test_drdpa_lock() allocated the cleanup // ticket. if ((lck->lk.old_polls != NULL) && (ticket >= lck->lk.cleanup_ticket)) { __kmp_free(lck->lk.old_polls); lck->lk.old_polls = NULL; lck->lk.cleanup_ticket = 0; } // Check to see if we should reconfigure the polling area. // If there is still a garbage polling area to be deallocated from a // previous reconfiguration, let a later thread reconfigure it. if (lck->lk.old_polls == NULL) { bool reconfigure = false; std::atomic *old_polls = polls; kmp_uint32 num_polls = TCR_4(lck->lk.num_polls); if (TCR_4(__kmp_nth) > (__kmp_avail_proc ? __kmp_avail_proc : __kmp_xproc)) { // We are in oversubscription mode. Contract the polling area // down to a single location, if that hasn't been done already. if (num_polls > 1) { reconfigure = true; num_polls = TCR_4(lck->lk.num_polls); mask = 0; num_polls = 1; polls = (std::atomic *)__kmp_allocate(num_polls * sizeof(*polls)); polls[0] = ticket; } } else { // We are in under/fully subscribed mode. Check the number of // threads waiting on the lock. The size of the polling area // should be at least the number of threads waiting. kmp_uint64 num_waiting = TCR_8(lck->lk.next_ticket) - ticket - 1; if (num_waiting > num_polls) { kmp_uint32 old_num_polls = num_polls; reconfigure = true; do { mask = (mask << 1) | 1; num_polls *= 2; } while (num_polls <= num_waiting); // Allocate the new polling area, and copy the relevant portion // of the old polling area to the new area. __kmp_allocate() // zeroes the memory it allocates, and most of the old area is // just zero padding, so we only copy the release counters. polls = (std::atomic *)__kmp_allocate(num_polls * sizeof(*polls)); kmp_uint32 i; for (i = 0; i < old_num_polls; i++) { polls[i].store(old_polls[i]); } } } if (reconfigure) { // Now write the updated fields back to the lock structure. // // Make certain that "polls" is written before "mask" !!! // // If another thread picks up the new value of mask and the old polls // pointer , it could access memory beyond the end of the old polling // area. // // On x86, we need memory fences. KA_TRACE(1000, ("__kmp_acquire_drdpa_lock: ticket #%lld reconfiguring " "lock %p to %d polls\n", ticket, lck, num_polls)); lck->lk.old_polls = old_polls; lck->lk.polls = polls; // atomic store KMP_MB(); lck->lk.num_polls = num_polls; lck->lk.mask = mask; // atomic store KMP_MB(); // Only after the new polling area and mask have been flushed // to main memory can we update the cleanup ticket field. // // volatile load / non-volatile store lck->lk.cleanup_ticket = lck->lk.next_ticket; } } return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_acquire_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { int retval = __kmp_acquire_drdpa_lock_timed_template(lck, gtid); return retval; } static int __kmp_acquire_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if ((gtid >= 0) && (__kmp_get_drdpa_lock_owner(lck) == gtid)) { KMP_FATAL(LockIsAlreadyOwned, func); } __kmp_acquire_drdpa_lock(lck, gtid); lck->lk.owner_id = gtid + 1; return KMP_LOCK_ACQUIRED_FIRST; } int __kmp_test_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { // First get a ticket, then read the polls pointer and the mask. // The polls pointer must be read before the mask!!! (See above) kmp_uint64 ticket = lck->lk.next_ticket; // atomic load std::atomic *polls = lck->lk.polls; kmp_uint64 mask = lck->lk.mask; // atomic load if (polls[ticket & mask] == ticket) { kmp_uint64 next_ticket = ticket + 1; if (__kmp_atomic_compare_store_acq(&lck->lk.next_ticket, ticket, next_ticket)) { KMP_FSYNC_ACQUIRED(lck); KA_TRACE(1000, ("__kmp_test_drdpa_lock: ticket #%lld acquired lock %p\n", ticket, lck)); lck->lk.now_serving = ticket; // non-volatile store // Since no threads are waiting, there is no possibility that we would // want to reconfigure the polling area. We might have the cleanup ticket // value (which says that it is now safe to deallocate old_polls), but // we'll let a later thread which calls __kmp_acquire_lock do that - this // routine isn't supposed to block, and we would risk blocks if we called // __kmp_free() to do the deallocation. return TRUE; } } return FALSE; } static int __kmp_test_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } int retval = __kmp_test_drdpa_lock(lck, gtid); if (retval) { lck->lk.owner_id = gtid + 1; } return retval; } int __kmp_release_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { // Read the ticket value from the lock data struct, then the polls pointer and // the mask. The polls pointer must be read before the mask!!! (See above) kmp_uint64 ticket = lck->lk.now_serving + 1; // non-atomic load std::atomic *polls = lck->lk.polls; // atomic load kmp_uint64 mask = lck->lk.mask; // atomic load KA_TRACE(1000, ("__kmp_release_drdpa_lock: ticket #%lld released lock %p\n", ticket - 1, lck)); KMP_FSYNC_RELEASING(lck); polls[ticket & mask] = ticket; // atomic store return KMP_LOCK_RELEASED; } static int __kmp_release_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_lock"; KMP_MB(); /* in case another processor initialized lock */ if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_drdpa_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if ((gtid >= 0) && (__kmp_get_drdpa_lock_owner(lck) >= 0) && (__kmp_get_drdpa_lock_owner(lck) != gtid)) { KMP_FATAL(LockUnsettingSetByAnother, func); } lck->lk.owner_id = 0; return __kmp_release_drdpa_lock(lck, gtid); } void __kmp_init_drdpa_lock(kmp_drdpa_lock_t *lck) { lck->lk.location = NULL; lck->lk.mask = 0; lck->lk.num_polls = 1; lck->lk.polls = (std::atomic *)__kmp_allocate( lck->lk.num_polls * sizeof(*(lck->lk.polls))); lck->lk.cleanup_ticket = 0; lck->lk.old_polls = NULL; lck->lk.next_ticket = 0; lck->lk.now_serving = 0; lck->lk.owner_id = 0; // no thread owns the lock. lck->lk.depth_locked = -1; // >= 0 for nestable locks, -1 for simple locks. lck->lk.initialized = lck; KA_TRACE(1000, ("__kmp_init_drdpa_lock: lock %p initialized\n", lck)); } void __kmp_destroy_drdpa_lock(kmp_drdpa_lock_t *lck) { lck->lk.initialized = NULL; lck->lk.location = NULL; if (lck->lk.polls.load() != NULL) { __kmp_free(lck->lk.polls.load()); lck->lk.polls = NULL; } if (lck->lk.old_polls != NULL) { __kmp_free(lck->lk.old_polls); lck->lk.old_polls = NULL; } lck->lk.mask = 0; lck->lk.num_polls = 0; lck->lk.cleanup_ticket = 0; lck->lk.next_ticket = 0; lck->lk.now_serving = 0; lck->lk.owner_id = 0; lck->lk.depth_locked = -1; } static void __kmp_destroy_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) { char const *const func = "omp_destroy_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockNestableUsedAsSimple, func); } if (__kmp_get_drdpa_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_drdpa_lock(lck); } // nested drdpa ticket locks int __kmp_acquire_nested_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_drdpa_lock_owner(lck) == gtid) { lck->lk.depth_locked += 1; return KMP_LOCK_ACQUIRED_NEXT; } else { __kmp_acquire_drdpa_lock_timed_template(lck, gtid); KMP_MB(); lck->lk.depth_locked = 1; KMP_MB(); lck->lk.owner_id = gtid + 1; return KMP_LOCK_ACQUIRED_FIRST; } } static void __kmp_acquire_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_set_nest_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } __kmp_acquire_nested_drdpa_lock(lck, gtid); } int __kmp_test_nested_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { int retval; KMP_DEBUG_ASSERT(gtid >= 0); if (__kmp_get_drdpa_lock_owner(lck) == gtid) { retval = ++lck->lk.depth_locked; } else if (!__kmp_test_drdpa_lock(lck, gtid)) { retval = 0; } else { KMP_MB(); retval = lck->lk.depth_locked = 1; KMP_MB(); lck->lk.owner_id = gtid + 1; } return retval; } static int __kmp_test_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_test_nest_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } return __kmp_test_nested_drdpa_lock(lck, gtid); } int __kmp_release_nested_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { KMP_DEBUG_ASSERT(gtid >= 0); KMP_MB(); if (--(lck->lk.depth_locked) == 0) { KMP_MB(); lck->lk.owner_id = 0; __kmp_release_drdpa_lock(lck, gtid); return KMP_LOCK_RELEASED; } return KMP_LOCK_STILL_HELD; } static int __kmp_release_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck, kmp_int32 gtid) { char const *const func = "omp_unset_nest_lock"; KMP_MB(); /* in case another processor initialized lock */ if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_drdpa_lock_owner(lck) == -1) { KMP_FATAL(LockUnsettingFree, func); } if (__kmp_get_drdpa_lock_owner(lck) != gtid) { KMP_FATAL(LockUnsettingSetByAnother, func); } return __kmp_release_nested_drdpa_lock(lck, gtid); } void __kmp_init_nested_drdpa_lock(kmp_drdpa_lock_t *lck) { __kmp_init_drdpa_lock(lck); lck->lk.depth_locked = 0; // >= 0 for nestable locks, -1 for simple locks } void __kmp_destroy_nested_drdpa_lock(kmp_drdpa_lock_t *lck) { __kmp_destroy_drdpa_lock(lck); lck->lk.depth_locked = 0; } static void __kmp_destroy_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) { char const *const func = "omp_destroy_nest_lock"; if (lck->lk.initialized != lck) { KMP_FATAL(LockIsUninitialized, func); } if (!__kmp_is_drdpa_lock_nestable(lck)) { KMP_FATAL(LockSimpleUsedAsNestable, func); } if (__kmp_get_drdpa_lock_owner(lck) != -1) { KMP_FATAL(LockStillOwned, func); } __kmp_destroy_nested_drdpa_lock(lck); } // access functions to fields which don't exist for all lock kinds. static const ident_t *__kmp_get_drdpa_lock_location(kmp_drdpa_lock_t *lck) { return lck->lk.location; } static void __kmp_set_drdpa_lock_location(kmp_drdpa_lock_t *lck, const ident_t *loc) { lck->lk.location = loc; } static kmp_lock_flags_t __kmp_get_drdpa_lock_flags(kmp_drdpa_lock_t *lck) { return lck->lk.flags; } static void __kmp_set_drdpa_lock_flags(kmp_drdpa_lock_t *lck, kmp_lock_flags_t flags) { lck->lk.flags = flags; } // Time stamp counter #if KMP_ARCH_X86 || KMP_ARCH_X86_64 #define __kmp_tsc() __kmp_hardware_timestamp() // Runtime's default backoff parameters kmp_backoff_t __kmp_spin_backoff_params = {1, 4096, 100}; #else // Use nanoseconds for other platforms extern kmp_uint64 __kmp_now_nsec(); kmp_backoff_t __kmp_spin_backoff_params = {1, 256, 100}; #define __kmp_tsc() __kmp_now_nsec() #endif // A useful predicate for dealing with timestamps that may wrap. // Is a before b? Since the timestamps may wrap, this is asking whether it's // shorter to go clockwise from a to b around the clock-face, or anti-clockwise. // Times where going clockwise is less distance than going anti-clockwise // are in the future, others are in the past. e.g. a = MAX-1, b = MAX+1 (=0), // then a > b (true) does not mean a reached b; whereas signed(a) = -2, // signed(b) = 0 captures the actual difference static inline bool before(kmp_uint64 a, kmp_uint64 b) { return ((kmp_int64)b - (kmp_int64)a) > 0; } // Truncated binary exponential backoff function void __kmp_spin_backoff(kmp_backoff_t *boff) { // We could flatten this loop, but making it a nested loop gives better result kmp_uint32 i; for (i = boff->step; i > 0; i--) { kmp_uint64 goal = __kmp_tsc() + boff->min_tick; #if KMP_HAVE_UMWAIT if (__kmp_umwait_enabled) { __kmp_tpause(0, boff->min_tick); } else { #endif do { KMP_CPU_PAUSE(); } while (before(__kmp_tsc(), goal)); #if KMP_HAVE_UMWAIT } #endif } boff->step = (boff->step << 1 | 1) & (boff->max_backoff - 1); } #if KMP_USE_DYNAMIC_LOCK // Direct lock initializers. It simply writes a tag to the low 8 bits of the // lock word. static void __kmp_init_direct_lock(kmp_dyna_lock_t *lck, kmp_dyna_lockseq_t seq) { TCW_4(*lck, KMP_GET_D_TAG(seq)); KA_TRACE( 20, ("__kmp_init_direct_lock: initialized direct lock with type#%d\n", seq)); } #if KMP_USE_TSX // HLE lock functions - imported from the testbed runtime. #define HLE_ACQUIRE ".byte 0xf2;" #define HLE_RELEASE ".byte 0xf3;" static inline kmp_uint32 swap4(kmp_uint32 volatile *p, kmp_uint32 v) { __asm__ volatile(HLE_ACQUIRE "xchg %1,%0" : "+r"(v), "+m"(*p) : : "memory"); return v; } static void __kmp_destroy_hle_lock(kmp_dyna_lock_t *lck) { TCW_4(*lck, 0); } static void __kmp_destroy_hle_lock_with_checks(kmp_dyna_lock_t *lck) { TCW_4(*lck, 0); } static void __kmp_acquire_hle_lock(kmp_dyna_lock_t *lck, kmp_int32 gtid) { // Use gtid for KMP_LOCK_BUSY if necessary if (swap4(lck, KMP_LOCK_BUSY(1, hle)) != KMP_LOCK_FREE(hle)) { int delay = 1; do { while (*(kmp_uint32 volatile *)lck != KMP_LOCK_FREE(hle)) { for (int i = delay; i != 0; --i) KMP_CPU_PAUSE(); delay = ((delay << 1) | 1) & 7; } } while (swap4(lck, KMP_LOCK_BUSY(1, hle)) != KMP_LOCK_FREE(hle)); } } static void __kmp_acquire_hle_lock_with_checks(kmp_dyna_lock_t *lck, kmp_int32 gtid) { __kmp_acquire_hle_lock(lck, gtid); // TODO: add checks } static int __kmp_release_hle_lock(kmp_dyna_lock_t *lck, kmp_int32 gtid) { __asm__ volatile(HLE_RELEASE "movl %1,%0" : "=m"(*lck) : "r"(KMP_LOCK_FREE(hle)) : "memory"); return KMP_LOCK_RELEASED; } static int __kmp_release_hle_lock_with_checks(kmp_dyna_lock_t *lck, kmp_int32 gtid) { return __kmp_release_hle_lock(lck, gtid); // TODO: add checks } static int __kmp_test_hle_lock(kmp_dyna_lock_t *lck, kmp_int32 gtid) { return swap4(lck, KMP_LOCK_BUSY(1, hle)) == KMP_LOCK_FREE(hle); } static int __kmp_test_hle_lock_with_checks(kmp_dyna_lock_t *lck, kmp_int32 gtid) { return __kmp_test_hle_lock(lck, gtid); // TODO: add checks } static void __kmp_init_rtm_queuing_lock(kmp_queuing_lock_t *lck) { __kmp_init_queuing_lock(lck); } static void __kmp_destroy_rtm_queuing_lock(kmp_queuing_lock_t *lck) { __kmp_destroy_queuing_lock(lck); } static void __kmp_destroy_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck) { __kmp_destroy_queuing_lock_with_checks(lck); } KMP_ATTRIBUTE_TARGET_RTM static void __kmp_acquire_rtm_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { unsigned retries = 3, status; do { status = _xbegin(); if (status == _XBEGIN_STARTED) { if (__kmp_is_unlocked_queuing_lock(lck)) return; _xabort(0xff); } if ((status & _XABORT_EXPLICIT) && _XABORT_CODE(status) == 0xff) { // Wait until lock becomes free while (!__kmp_is_unlocked_queuing_lock(lck)) { KMP_YIELD(TRUE); } } else if (!(status & _XABORT_RETRY)) break; } while (retries--); // Fall-back non-speculative lock (xchg) __kmp_acquire_queuing_lock(lck, gtid); } static void __kmp_acquire_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { __kmp_acquire_rtm_queuing_lock(lck, gtid); } KMP_ATTRIBUTE_TARGET_RTM static int __kmp_release_rtm_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { if (__kmp_is_unlocked_queuing_lock(lck)) { // Releasing from speculation _xend(); } else { // Releasing from a real lock __kmp_release_queuing_lock(lck, gtid); } return KMP_LOCK_RELEASED; } static int __kmp_release_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { return __kmp_release_rtm_queuing_lock(lck, gtid); } KMP_ATTRIBUTE_TARGET_RTM static int __kmp_test_rtm_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid) { unsigned retries = 3, status; do { status = _xbegin(); if (status == _XBEGIN_STARTED && __kmp_is_unlocked_queuing_lock(lck)) { return 1; } if (!(status & _XABORT_RETRY)) break; } while (retries--); return __kmp_test_queuing_lock(lck, gtid); } static int __kmp_test_rtm_queuing_lock_with_checks(kmp_queuing_lock_t *lck, kmp_int32 gtid) { return __kmp_test_rtm_queuing_lock(lck, gtid); } // Reuse kmp_tas_lock_t for TSX lock which use RTM with fall-back spin lock. typedef kmp_tas_lock_t kmp_rtm_spin_lock_t; static void __kmp_destroy_rtm_spin_lock(kmp_rtm_spin_lock_t *lck) { KMP_ATOMIC_ST_REL(&lck->lk.poll, 0); } static void __kmp_destroy_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck) { __kmp_destroy_rtm_spin_lock(lck); } KMP_ATTRIBUTE_TARGET_RTM static int __kmp_acquire_rtm_spin_lock(kmp_rtm_spin_lock_t *lck, kmp_int32 gtid) { unsigned retries = 3, status; kmp_int32 lock_free = KMP_LOCK_FREE(rtm_spin); kmp_int32 lock_busy = KMP_LOCK_BUSY(1, rtm_spin); do { status = _xbegin(); if (status == _XBEGIN_STARTED) { if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == lock_free) return KMP_LOCK_ACQUIRED_FIRST; _xabort(0xff); } if ((status & _XABORT_EXPLICIT) && _XABORT_CODE(status) == 0xff) { // Wait until lock becomes free while (KMP_ATOMIC_LD_RLX(&lck->lk.poll) != lock_free) { KMP_YIELD(TRUE); } } else if (!(status & _XABORT_RETRY)) break; } while (retries--); // Fall-back spin lock KMP_FSYNC_PREPARE(lck); kmp_backoff_t backoff = __kmp_spin_backoff_params; while (KMP_ATOMIC_LD_RLX(&lck->lk.poll) != lock_free || !__kmp_atomic_compare_store_acq(&lck->lk.poll, lock_free, lock_busy)) { __kmp_spin_backoff(&backoff); } KMP_FSYNC_ACQUIRED(lck); return KMP_LOCK_ACQUIRED_FIRST; } static int __kmp_acquire_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck, kmp_int32 gtid) { return __kmp_acquire_rtm_spin_lock(lck, gtid); } KMP_ATTRIBUTE_TARGET_RTM static int __kmp_release_rtm_spin_lock(kmp_rtm_spin_lock_t *lck, kmp_int32 gtid) { if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == KMP_LOCK_FREE(rtm_spin)) { // Releasing from speculation _xend(); } else { // Releasing from a real lock KMP_FSYNC_RELEASING(lck); KMP_ATOMIC_ST_REL(&lck->lk.poll, KMP_LOCK_FREE(rtm_spin)); } return KMP_LOCK_RELEASED; } static int __kmp_release_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck, kmp_int32 gtid) { return __kmp_release_rtm_spin_lock(lck, gtid); } KMP_ATTRIBUTE_TARGET_RTM static int __kmp_test_rtm_spin_lock(kmp_rtm_spin_lock_t *lck, kmp_int32 gtid) { unsigned retries = 3, status; kmp_int32 lock_free = KMP_LOCK_FREE(rtm_spin); kmp_int32 lock_busy = KMP_LOCK_BUSY(1, rtm_spin); do { status = _xbegin(); if (status == _XBEGIN_STARTED && KMP_ATOMIC_LD_RLX(&lck->lk.poll) == lock_free) { return TRUE; } if (!(status & _XABORT_RETRY)) break; } while (retries--); if (KMP_ATOMIC_LD_RLX(&lck->lk.poll) == lock_free && __kmp_atomic_compare_store_acq(&lck->lk.poll, lock_free, lock_busy)) { KMP_FSYNC_ACQUIRED(lck); return TRUE; } return FALSE; } static int __kmp_test_rtm_spin_lock_with_checks(kmp_rtm_spin_lock_t *lck, kmp_int32 gtid) { return __kmp_test_rtm_spin_lock(lck, gtid); } #endif // KMP_USE_TSX // Entry functions for indirect locks (first element of direct lock jump tables) static void __kmp_init_indirect_lock(kmp_dyna_lock_t *l, kmp_dyna_lockseq_t tag); static void __kmp_destroy_indirect_lock(kmp_dyna_lock_t *lock); static int __kmp_set_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32); static int __kmp_unset_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32); static int __kmp_test_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32); static int __kmp_set_indirect_lock_with_checks(kmp_dyna_lock_t *lock, kmp_int32); static int __kmp_unset_indirect_lock_with_checks(kmp_dyna_lock_t *lock, kmp_int32); static int __kmp_test_indirect_lock_with_checks(kmp_dyna_lock_t *lock, kmp_int32); // Lock function definitions for the union parameter type #define KMP_FOREACH_LOCK_KIND(m, a) m(ticket, a) m(queuing, a) m(drdpa, a) #define expand1(lk, op) \ static void __kmp_##op##_##lk##_##lock(kmp_user_lock_p lock) { \ __kmp_##op##_##lk##_##lock(&lock->lk); \ } #define expand2(lk, op) \ static int __kmp_##op##_##lk##_##lock(kmp_user_lock_p lock, \ kmp_int32 gtid) { \ return __kmp_##op##_##lk##_##lock(&lock->lk, gtid); \ } #define expand3(lk, op) \ static void __kmp_set_##lk##_##lock_flags(kmp_user_lock_p lock, \ kmp_lock_flags_t flags) { \ __kmp_set_##lk##_lock_flags(&lock->lk, flags); \ } #define expand4(lk, op) \ static void __kmp_set_##lk##_##lock_location(kmp_user_lock_p lock, \ const ident_t *loc) { \ __kmp_set_##lk##_lock_location(&lock->lk, loc); \ } KMP_FOREACH_LOCK_KIND(expand1, init) KMP_FOREACH_LOCK_KIND(expand1, init_nested) KMP_FOREACH_LOCK_KIND(expand1, destroy) KMP_FOREACH_LOCK_KIND(expand1, destroy_nested) KMP_FOREACH_LOCK_KIND(expand2, acquire) KMP_FOREACH_LOCK_KIND(expand2, acquire_nested) KMP_FOREACH_LOCK_KIND(expand2, release) KMP_FOREACH_LOCK_KIND(expand2, release_nested) KMP_FOREACH_LOCK_KIND(expand2, test) KMP_FOREACH_LOCK_KIND(expand2, test_nested) KMP_FOREACH_LOCK_KIND(expand3, ) KMP_FOREACH_LOCK_KIND(expand4, ) #undef expand1 #undef expand2 #undef expand3 #undef expand4 // Jump tables for the indirect lock functions // Only fill in the odd entries, that avoids the need to shift out the low bit // init functions #define expand(l, op) 0, __kmp_init_direct_lock, void (*__kmp_direct_init[])(kmp_dyna_lock_t *, kmp_dyna_lockseq_t) = { __kmp_init_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, init)}; #undef expand // destroy functions #define expand(l, op) 0, (void (*)(kmp_dyna_lock_t *))__kmp_##op##_##l##_lock, static void (*direct_destroy[])(kmp_dyna_lock_t *) = { __kmp_destroy_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, destroy)}; #undef expand #define expand(l, op) \ 0, (void (*)(kmp_dyna_lock_t *))__kmp_destroy_##l##_lock_with_checks, static void (*direct_destroy_check[])(kmp_dyna_lock_t *) = { __kmp_destroy_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, destroy)}; #undef expand // set/acquire functions #define expand(l, op) \ 0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock, static int (*direct_set[])(kmp_dyna_lock_t *, kmp_int32) = { __kmp_set_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, acquire)}; #undef expand #define expand(l, op) \ 0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock_with_checks, static int (*direct_set_check[])(kmp_dyna_lock_t *, kmp_int32) = { __kmp_set_indirect_lock_with_checks, 0, KMP_FOREACH_D_LOCK(expand, acquire)}; #undef expand // unset/release and test functions #define expand(l, op) \ 0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock, static int (*direct_unset[])(kmp_dyna_lock_t *, kmp_int32) = { __kmp_unset_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, release)}; static int (*direct_test[])(kmp_dyna_lock_t *, kmp_int32) = { __kmp_test_indirect_lock, 0, KMP_FOREACH_D_LOCK(expand, test)}; #undef expand #define expand(l, op) \ 0, (int (*)(kmp_dyna_lock_t *, kmp_int32))__kmp_##op##_##l##_lock_with_checks, static int (*direct_unset_check[])(kmp_dyna_lock_t *, kmp_int32) = { __kmp_unset_indirect_lock_with_checks, 0, KMP_FOREACH_D_LOCK(expand, release)}; static int (*direct_test_check[])(kmp_dyna_lock_t *, kmp_int32) = { __kmp_test_indirect_lock_with_checks, 0, KMP_FOREACH_D_LOCK(expand, test)}; #undef expand // Exposes only one set of jump tables (*lock or *lock_with_checks). void (**__kmp_direct_destroy)(kmp_dyna_lock_t *) = 0; int (**__kmp_direct_set)(kmp_dyna_lock_t *, kmp_int32) = 0; int (**__kmp_direct_unset)(kmp_dyna_lock_t *, kmp_int32) = 0; int (**__kmp_direct_test)(kmp_dyna_lock_t *, kmp_int32) = 0; // Jump tables for the indirect lock functions #define expand(l, op) (void (*)(kmp_user_lock_p)) __kmp_##op##_##l##_##lock, void (*__kmp_indirect_init[])(kmp_user_lock_p) = { KMP_FOREACH_I_LOCK(expand, init)}; #undef expand #define expand(l, op) (void (*)(kmp_user_lock_p)) __kmp_##op##_##l##_##lock, static void (*indirect_destroy[])(kmp_user_lock_p) = { KMP_FOREACH_I_LOCK(expand, destroy)}; #undef expand #define expand(l, op) \ (void (*)(kmp_user_lock_p)) __kmp_##op##_##l##_##lock_with_checks, static void (*indirect_destroy_check[])(kmp_user_lock_p) = { KMP_FOREACH_I_LOCK(expand, destroy)}; #undef expand // set/acquire functions #define expand(l, op) \ (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock, static int (*indirect_set[])(kmp_user_lock_p, kmp_int32) = {KMP_FOREACH_I_LOCK(expand, acquire)}; #undef expand #define expand(l, op) \ (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock_with_checks, static int (*indirect_set_check[])(kmp_user_lock_p, kmp_int32) = { KMP_FOREACH_I_LOCK(expand, acquire)}; #undef expand // unset/release and test functions #define expand(l, op) \ (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock, static int (*indirect_unset[])(kmp_user_lock_p, kmp_int32) = { KMP_FOREACH_I_LOCK(expand, release)}; static int (*indirect_test[])(kmp_user_lock_p, kmp_int32) = {KMP_FOREACH_I_LOCK(expand, test)}; #undef expand #define expand(l, op) \ (int (*)(kmp_user_lock_p, kmp_int32)) __kmp_##op##_##l##_##lock_with_checks, static int (*indirect_unset_check[])(kmp_user_lock_p, kmp_int32) = { KMP_FOREACH_I_LOCK(expand, release)}; static int (*indirect_test_check[])(kmp_user_lock_p, kmp_int32) = { KMP_FOREACH_I_LOCK(expand, test)}; #undef expand // Exposes only one jump tables (*lock or *lock_with_checks). void (**__kmp_indirect_destroy)(kmp_user_lock_p) = 0; int (**__kmp_indirect_set)(kmp_user_lock_p, kmp_int32) = 0; int (**__kmp_indirect_unset)(kmp_user_lock_p, kmp_int32) = 0; int (**__kmp_indirect_test)(kmp_user_lock_p, kmp_int32) = 0; // Lock index table. kmp_indirect_lock_table_t __kmp_i_lock_table; // Size of indirect locks. static kmp_uint32 __kmp_indirect_lock_size[KMP_NUM_I_LOCKS] = {0}; // Jump tables for lock accessor/modifier. void (*__kmp_indirect_set_location[KMP_NUM_I_LOCKS])(kmp_user_lock_p, const ident_t *) = {0}; void (*__kmp_indirect_set_flags[KMP_NUM_I_LOCKS])(kmp_user_lock_p, kmp_lock_flags_t) = {0}; const ident_t *(*__kmp_indirect_get_location[KMP_NUM_I_LOCKS])( kmp_user_lock_p) = {0}; kmp_lock_flags_t (*__kmp_indirect_get_flags[KMP_NUM_I_LOCKS])( kmp_user_lock_p) = {0}; // Use different lock pools for different lock types. static kmp_indirect_lock_t *__kmp_indirect_lock_pool[KMP_NUM_I_LOCKS] = {0}; // User lock allocator for dynamically dispatched indirect locks. Every entry of // the indirect lock table holds the address and type of the allocated indirect // lock (kmp_indirect_lock_t), and the size of the table doubles when it is // full. A destroyed indirect lock object is returned to the reusable pool of // locks, unique to each lock type. kmp_indirect_lock_t *__kmp_allocate_indirect_lock(void **user_lock, kmp_int32 gtid, kmp_indirect_locktag_t tag) { kmp_indirect_lock_t *lck; kmp_lock_index_t idx, table_idx; __kmp_acquire_lock(&__kmp_global_lock, gtid); if (__kmp_indirect_lock_pool[tag] != NULL) { // Reuse the allocated and destroyed lock object lck = __kmp_indirect_lock_pool[tag]; if (OMP_LOCK_T_SIZE < sizeof(void *)) idx = lck->lock->pool.index; __kmp_indirect_lock_pool[tag] = (kmp_indirect_lock_t *)lck->lock->pool.next; KA_TRACE(20, ("__kmp_allocate_indirect_lock: reusing an existing lock %p\n", lck)); } else { kmp_uint32 row, col; kmp_indirect_lock_table_t *lock_table = &__kmp_i_lock_table; idx = 0; // Find location in list of lock tables to put new lock while (1) { table_idx = lock_table->next; // index within this table idx += lock_table->next; // global index within list of tables if (table_idx < lock_table->nrow_ptrs * KMP_I_LOCK_CHUNK) { row = table_idx / KMP_I_LOCK_CHUNK; col = table_idx % KMP_I_LOCK_CHUNK; // Allocate a new row of locks if necessary if (!lock_table->table[row]) { lock_table->table[row] = (kmp_indirect_lock_t *)__kmp_allocate( sizeof(kmp_indirect_lock_t) * KMP_I_LOCK_CHUNK); } break; } // Allocate a new lock table if necessary with double the capacity if (!lock_table->next_table) { kmp_indirect_lock_table_t *next_table = (kmp_indirect_lock_table_t *)__kmp_allocate( sizeof(kmp_indirect_lock_table_t)); next_table->table = (kmp_indirect_lock_t **)__kmp_allocate( sizeof(kmp_indirect_lock_t *) * 2 * lock_table->nrow_ptrs); next_table->nrow_ptrs = 2 * lock_table->nrow_ptrs; next_table->next = 0; next_table->next_table = nullptr; lock_table->next_table = next_table; } lock_table = lock_table->next_table; KMP_ASSERT(lock_table); } lock_table->next++; lck = &lock_table->table[row][col]; // Allocate a new base lock object lck->lock = (kmp_user_lock_p)__kmp_allocate(__kmp_indirect_lock_size[tag]); KA_TRACE(20, ("__kmp_allocate_indirect_lock: allocated a new lock %p\n", lck)); } __kmp_release_lock(&__kmp_global_lock, gtid); lck->type = tag; if (OMP_LOCK_T_SIZE < sizeof(void *)) { *((kmp_lock_index_t *)user_lock) = idx << 1; // indirect lock word must be even } else { *((kmp_indirect_lock_t **)user_lock) = lck; } return lck; } // User lock lookup for dynamically dispatched locks. static __forceinline kmp_indirect_lock_t * __kmp_lookup_indirect_lock(void **user_lock, const char *func) { if (__kmp_env_consistency_check) { kmp_indirect_lock_t *lck = NULL; if (user_lock == NULL) { KMP_FATAL(LockIsUninitialized, func); } if (OMP_LOCK_T_SIZE < sizeof(void *)) { kmp_lock_index_t idx = KMP_EXTRACT_I_INDEX(user_lock); lck = __kmp_get_i_lock(idx); } else { lck = *((kmp_indirect_lock_t **)user_lock); } if (lck == NULL) { KMP_FATAL(LockIsUninitialized, func); } return lck; } else { if (OMP_LOCK_T_SIZE < sizeof(void *)) { return __kmp_get_i_lock(KMP_EXTRACT_I_INDEX(user_lock)); } else { return *((kmp_indirect_lock_t **)user_lock); } } } static void __kmp_init_indirect_lock(kmp_dyna_lock_t *lock, kmp_dyna_lockseq_t seq) { #if KMP_USE_ADAPTIVE_LOCKS if (seq == lockseq_adaptive && !__kmp_cpuinfo.flags.rtm) { KMP_WARNING(AdaptiveNotSupported, "kmp_lockseq_t", "adaptive"); seq = lockseq_queuing; } #endif #if KMP_USE_TSX if (seq == lockseq_rtm_queuing && !__kmp_cpuinfo.flags.rtm) { seq = lockseq_queuing; } #endif kmp_indirect_locktag_t tag = KMP_GET_I_TAG(seq); kmp_indirect_lock_t *l = __kmp_allocate_indirect_lock((void **)lock, __kmp_entry_gtid(), tag); KMP_I_LOCK_FUNC(l, init)(l->lock); KA_TRACE( 20, ("__kmp_init_indirect_lock: initialized indirect lock with type#%d\n", seq)); } static void __kmp_destroy_indirect_lock(kmp_dyna_lock_t *lock) { kmp_uint32 gtid = __kmp_entry_gtid(); kmp_indirect_lock_t *l = __kmp_lookup_indirect_lock((void **)lock, "omp_destroy_lock"); KMP_I_LOCK_FUNC(l, destroy)(l->lock); kmp_indirect_locktag_t tag = l->type; __kmp_acquire_lock(&__kmp_global_lock, gtid); // Use the base lock's space to keep the pool chain. l->lock->pool.next = (kmp_user_lock_p)__kmp_indirect_lock_pool[tag]; if (OMP_LOCK_T_SIZE < sizeof(void *)) { l->lock->pool.index = KMP_EXTRACT_I_INDEX(lock); } __kmp_indirect_lock_pool[tag] = l; __kmp_release_lock(&__kmp_global_lock, gtid); } static int __kmp_set_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32 gtid) { kmp_indirect_lock_t *l = KMP_LOOKUP_I_LOCK(lock); return KMP_I_LOCK_FUNC(l, set)(l->lock, gtid); } static int __kmp_unset_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32 gtid) { kmp_indirect_lock_t *l = KMP_LOOKUP_I_LOCK(lock); return KMP_I_LOCK_FUNC(l, unset)(l->lock, gtid); } static int __kmp_test_indirect_lock(kmp_dyna_lock_t *lock, kmp_int32 gtid) { kmp_indirect_lock_t *l = KMP_LOOKUP_I_LOCK(lock); return KMP_I_LOCK_FUNC(l, test)(l->lock, gtid); } static int __kmp_set_indirect_lock_with_checks(kmp_dyna_lock_t *lock, kmp_int32 gtid) { kmp_indirect_lock_t *l = __kmp_lookup_indirect_lock((void **)lock, "omp_set_lock"); return KMP_I_LOCK_FUNC(l, set)(l->lock, gtid); } static int __kmp_unset_indirect_lock_with_checks(kmp_dyna_lock_t *lock, kmp_int32 gtid) { kmp_indirect_lock_t *l = __kmp_lookup_indirect_lock((void **)lock, "omp_unset_lock"); return KMP_I_LOCK_FUNC(l, unset)(l->lock, gtid); } static int __kmp_test_indirect_lock_with_checks(kmp_dyna_lock_t *lock, kmp_int32 gtid) { kmp_indirect_lock_t *l = __kmp_lookup_indirect_lock((void **)lock, "omp_test_lock"); return KMP_I_LOCK_FUNC(l, test)(l->lock, gtid); } kmp_dyna_lockseq_t __kmp_user_lock_seq = lockseq_queuing; // This is used only in kmp_error.cpp when consistency checking is on. kmp_int32 __kmp_get_user_lock_owner(kmp_user_lock_p lck, kmp_uint32 seq) { switch (seq) { case lockseq_tas: case lockseq_nested_tas: return __kmp_get_tas_lock_owner((kmp_tas_lock_t *)lck); #if KMP_USE_FUTEX case lockseq_futex: case lockseq_nested_futex: return __kmp_get_futex_lock_owner((kmp_futex_lock_t *)lck); #endif case lockseq_ticket: case lockseq_nested_ticket: return __kmp_get_ticket_lock_owner((kmp_ticket_lock_t *)lck); case lockseq_queuing: case lockseq_nested_queuing: #if KMP_USE_ADAPTIVE_LOCKS case lockseq_adaptive: #endif return __kmp_get_queuing_lock_owner((kmp_queuing_lock_t *)lck); case lockseq_drdpa: case lockseq_nested_drdpa: return __kmp_get_drdpa_lock_owner((kmp_drdpa_lock_t *)lck); default: return 0; } } // Initializes data for dynamic user locks. void __kmp_init_dynamic_user_locks() { // Initialize jump table for the lock functions if (__kmp_env_consistency_check) { __kmp_direct_set = direct_set_check; __kmp_direct_unset = direct_unset_check; __kmp_direct_test = direct_test_check; __kmp_direct_destroy = direct_destroy_check; __kmp_indirect_set = indirect_set_check; __kmp_indirect_unset = indirect_unset_check; __kmp_indirect_test = indirect_test_check; __kmp_indirect_destroy = indirect_destroy_check; } else { __kmp_direct_set = direct_set; __kmp_direct_unset = direct_unset; __kmp_direct_test = direct_test; __kmp_direct_destroy = direct_destroy; __kmp_indirect_set = indirect_set; __kmp_indirect_unset = indirect_unset; __kmp_indirect_test = indirect_test; __kmp_indirect_destroy = indirect_destroy; } // If the user locks have already been initialized, then return. Allow the // switch between different KMP_CONSISTENCY_CHECK values, but do not allocate // new lock tables if they have already been allocated. if (__kmp_init_user_locks) return; // Initialize lock index table __kmp_i_lock_table.nrow_ptrs = KMP_I_LOCK_TABLE_INIT_NROW_PTRS; __kmp_i_lock_table.table = (kmp_indirect_lock_t **)__kmp_allocate( sizeof(kmp_indirect_lock_t *) * KMP_I_LOCK_TABLE_INIT_NROW_PTRS); *(__kmp_i_lock_table.table) = (kmp_indirect_lock_t *)__kmp_allocate( KMP_I_LOCK_CHUNK * sizeof(kmp_indirect_lock_t)); __kmp_i_lock_table.next = 0; __kmp_i_lock_table.next_table = nullptr; // Indirect lock size __kmp_indirect_lock_size[locktag_ticket] = sizeof(kmp_ticket_lock_t); __kmp_indirect_lock_size[locktag_queuing] = sizeof(kmp_queuing_lock_t); #if KMP_USE_ADAPTIVE_LOCKS __kmp_indirect_lock_size[locktag_adaptive] = sizeof(kmp_adaptive_lock_t); #endif __kmp_indirect_lock_size[locktag_drdpa] = sizeof(kmp_drdpa_lock_t); #if KMP_USE_TSX __kmp_indirect_lock_size[locktag_rtm_queuing] = sizeof(kmp_queuing_lock_t); #endif __kmp_indirect_lock_size[locktag_nested_tas] = sizeof(kmp_tas_lock_t); #if KMP_USE_FUTEX __kmp_indirect_lock_size[locktag_nested_futex] = sizeof(kmp_futex_lock_t); #endif __kmp_indirect_lock_size[locktag_nested_ticket] = sizeof(kmp_ticket_lock_t); __kmp_indirect_lock_size[locktag_nested_queuing] = sizeof(kmp_queuing_lock_t); __kmp_indirect_lock_size[locktag_nested_drdpa] = sizeof(kmp_drdpa_lock_t); // Initialize lock accessor/modifier #define fill_jumps(table, expand, sep) \ { \ table[locktag##sep##ticket] = expand(ticket); \ table[locktag##sep##queuing] = expand(queuing); \ table[locktag##sep##drdpa] = expand(drdpa); \ } #if KMP_USE_ADAPTIVE_LOCKS #define fill_table(table, expand) \ { \ fill_jumps(table, expand, _); \ table[locktag_adaptive] = expand(queuing); \ fill_jumps(table, expand, _nested_); \ } #else #define fill_table(table, expand) \ { \ fill_jumps(table, expand, _); \ fill_jumps(table, expand, _nested_); \ } #endif // KMP_USE_ADAPTIVE_LOCKS #define expand(l) \ (void (*)(kmp_user_lock_p, const ident_t *)) __kmp_set_##l##_lock_location fill_table(__kmp_indirect_set_location, expand); #undef expand #define expand(l) \ (void (*)(kmp_user_lock_p, kmp_lock_flags_t)) __kmp_set_##l##_lock_flags fill_table(__kmp_indirect_set_flags, expand); #undef expand #define expand(l) \ (const ident_t *(*)(kmp_user_lock_p)) __kmp_get_##l##_lock_location fill_table(__kmp_indirect_get_location, expand); #undef expand #define expand(l) \ (kmp_lock_flags_t(*)(kmp_user_lock_p)) __kmp_get_##l##_lock_flags fill_table(__kmp_indirect_get_flags, expand); #undef expand __kmp_init_user_locks = TRUE; } // Clean up the lock table. void __kmp_cleanup_indirect_user_locks() { int k; // Clean up locks in the pools first (they were already destroyed before going // into the pools). for (k = 0; k < KMP_NUM_I_LOCKS; ++k) { kmp_indirect_lock_t *l = __kmp_indirect_lock_pool[k]; while (l != NULL) { kmp_indirect_lock_t *ll = l; l = (kmp_indirect_lock_t *)l->lock->pool.next; KA_TRACE(20, ("__kmp_cleanup_indirect_user_locks: freeing %p from pool\n", ll)); __kmp_free(ll->lock); ll->lock = NULL; } __kmp_indirect_lock_pool[k] = NULL; } // Clean up the remaining undestroyed locks. kmp_indirect_lock_table_t *ptr = &__kmp_i_lock_table; while (ptr) { for (kmp_uint32 row = 0; row < ptr->nrow_ptrs; ++row) { if (!ptr->table[row]) continue; for (kmp_uint32 col = 0; col < KMP_I_LOCK_CHUNK; ++col) { kmp_indirect_lock_t *l = &ptr->table[row][col]; if (l->lock) { // Locks not destroyed explicitly need to be destroyed here. KMP_I_LOCK_FUNC(l, destroy)(l->lock); KA_TRACE(20, ("__kmp_cleanup_indirect_user_locks: destroy/freeing %p " "from table\n", l)); __kmp_free(l->lock); } } __kmp_free(ptr->table[row]); } kmp_indirect_lock_table_t *next_table = ptr->next_table; if (ptr != &__kmp_i_lock_table) __kmp_free(ptr); ptr = next_table; } __kmp_init_user_locks = FALSE; } enum kmp_lock_kind __kmp_user_lock_kind = lk_default; int __kmp_num_locks_in_block = 1; // FIXME - tune this value #else // KMP_USE_DYNAMIC_LOCK static void __kmp_init_tas_lock_with_checks(kmp_tas_lock_t *lck) { __kmp_init_tas_lock(lck); } static void __kmp_init_nested_tas_lock_with_checks(kmp_tas_lock_t *lck) { __kmp_init_nested_tas_lock(lck); } #if KMP_USE_FUTEX static void __kmp_init_futex_lock_with_checks(kmp_futex_lock_t *lck) { __kmp_init_futex_lock(lck); } static void __kmp_init_nested_futex_lock_with_checks(kmp_futex_lock_t *lck) { __kmp_init_nested_futex_lock(lck); } #endif static int __kmp_is_ticket_lock_initialized(kmp_ticket_lock_t *lck) { return lck == lck->lk.self; } static void __kmp_init_ticket_lock_with_checks(kmp_ticket_lock_t *lck) { __kmp_init_ticket_lock(lck); } static void __kmp_init_nested_ticket_lock_with_checks(kmp_ticket_lock_t *lck) { __kmp_init_nested_ticket_lock(lck); } static int __kmp_is_queuing_lock_initialized(kmp_queuing_lock_t *lck) { return lck == lck->lk.initialized; } static void __kmp_init_queuing_lock_with_checks(kmp_queuing_lock_t *lck) { __kmp_init_queuing_lock(lck); } static void __kmp_init_nested_queuing_lock_with_checks(kmp_queuing_lock_t *lck) { __kmp_init_nested_queuing_lock(lck); } #if KMP_USE_ADAPTIVE_LOCKS static void __kmp_init_adaptive_lock_with_checks(kmp_adaptive_lock_t *lck) { __kmp_init_adaptive_lock(lck); } #endif static int __kmp_is_drdpa_lock_initialized(kmp_drdpa_lock_t *lck) { return lck == lck->lk.initialized; } static void __kmp_init_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) { __kmp_init_drdpa_lock(lck); } static void __kmp_init_nested_drdpa_lock_with_checks(kmp_drdpa_lock_t *lck) { __kmp_init_nested_drdpa_lock(lck); } /* user locks * They are implemented as a table of function pointers which are set to the * lock functions of the appropriate kind, once that has been determined. */ enum kmp_lock_kind __kmp_user_lock_kind = lk_default; size_t __kmp_base_user_lock_size = 0; size_t __kmp_user_lock_size = 0; kmp_int32 (*__kmp_get_user_lock_owner_)(kmp_user_lock_p lck) = NULL; int (*__kmp_acquire_user_lock_with_checks_)(kmp_user_lock_p lck, kmp_int32 gtid) = NULL; int (*__kmp_test_user_lock_with_checks_)(kmp_user_lock_p lck, kmp_int32 gtid) = NULL; int (*__kmp_release_user_lock_with_checks_)(kmp_user_lock_p lck, kmp_int32 gtid) = NULL; void (*__kmp_init_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL; void (*__kmp_destroy_user_lock_)(kmp_user_lock_p lck) = NULL; void (*__kmp_destroy_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL; int (*__kmp_acquire_nested_user_lock_with_checks_)(kmp_user_lock_p lck, kmp_int32 gtid) = NULL; int (*__kmp_test_nested_user_lock_with_checks_)(kmp_user_lock_p lck, kmp_int32 gtid) = NULL; int (*__kmp_release_nested_user_lock_with_checks_)(kmp_user_lock_p lck, kmp_int32 gtid) = NULL; void (*__kmp_init_nested_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL; void (*__kmp_destroy_nested_user_lock_with_checks_)(kmp_user_lock_p lck) = NULL; int (*__kmp_is_user_lock_initialized_)(kmp_user_lock_p lck) = NULL; const ident_t *(*__kmp_get_user_lock_location_)(kmp_user_lock_p lck) = NULL; void (*__kmp_set_user_lock_location_)(kmp_user_lock_p lck, const ident_t *loc) = NULL; kmp_lock_flags_t (*__kmp_get_user_lock_flags_)(kmp_user_lock_p lck) = NULL; void (*__kmp_set_user_lock_flags_)(kmp_user_lock_p lck, kmp_lock_flags_t flags) = NULL; void __kmp_set_user_lock_vptrs(kmp_lock_kind_t user_lock_kind) { switch (user_lock_kind) { case lk_default: default: KMP_ASSERT(0); case lk_tas: { __kmp_base_user_lock_size = sizeof(kmp_base_tas_lock_t); __kmp_user_lock_size = sizeof(kmp_tas_lock_t); __kmp_get_user_lock_owner_ = (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_tas_lock_owner); if (__kmp_env_consistency_check) { KMP_BIND_USER_LOCK_WITH_CHECKS(tas); KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(tas); } else { KMP_BIND_USER_LOCK(tas); KMP_BIND_NESTED_USER_LOCK(tas); } __kmp_destroy_user_lock_ = (void (*)(kmp_user_lock_p))(&__kmp_destroy_tas_lock); __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))NULL; __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))NULL; __kmp_set_user_lock_location_ = (void (*)(kmp_user_lock_p, const ident_t *))NULL; __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))NULL; __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))NULL; } break; #if KMP_USE_FUTEX case lk_futex: { __kmp_base_user_lock_size = sizeof(kmp_base_futex_lock_t); __kmp_user_lock_size = sizeof(kmp_futex_lock_t); __kmp_get_user_lock_owner_ = (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_futex_lock_owner); if (__kmp_env_consistency_check) { KMP_BIND_USER_LOCK_WITH_CHECKS(futex); KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(futex); } else { KMP_BIND_USER_LOCK(futex); KMP_BIND_NESTED_USER_LOCK(futex); } __kmp_destroy_user_lock_ = (void (*)(kmp_user_lock_p))(&__kmp_destroy_futex_lock); __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))NULL; __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))NULL; __kmp_set_user_lock_location_ = (void (*)(kmp_user_lock_p, const ident_t *))NULL; __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))NULL; __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))NULL; } break; #endif // KMP_USE_FUTEX case lk_ticket: { __kmp_base_user_lock_size = sizeof(kmp_base_ticket_lock_t); __kmp_user_lock_size = sizeof(kmp_ticket_lock_t); __kmp_get_user_lock_owner_ = (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_ticket_lock_owner); if (__kmp_env_consistency_check) { KMP_BIND_USER_LOCK_WITH_CHECKS(ticket); KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(ticket); } else { KMP_BIND_USER_LOCK(ticket); KMP_BIND_NESTED_USER_LOCK(ticket); } __kmp_destroy_user_lock_ = (void (*)(kmp_user_lock_p))(&__kmp_destroy_ticket_lock); __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))(&__kmp_is_ticket_lock_initialized); __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_ticket_lock_location); __kmp_set_user_lock_location_ = (void (*)( kmp_user_lock_p, const ident_t *))(&__kmp_set_ticket_lock_location); __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_ticket_lock_flags); __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))( &__kmp_set_ticket_lock_flags); } break; case lk_queuing: { __kmp_base_user_lock_size = sizeof(kmp_base_queuing_lock_t); __kmp_user_lock_size = sizeof(kmp_queuing_lock_t); __kmp_get_user_lock_owner_ = (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_owner); if (__kmp_env_consistency_check) { KMP_BIND_USER_LOCK_WITH_CHECKS(queuing); KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(queuing); } else { KMP_BIND_USER_LOCK(queuing); KMP_BIND_NESTED_USER_LOCK(queuing); } __kmp_destroy_user_lock_ = (void (*)(kmp_user_lock_p))(&__kmp_destroy_queuing_lock); __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))(&__kmp_is_queuing_lock_initialized); __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_location); __kmp_set_user_lock_location_ = (void (*)( kmp_user_lock_p, const ident_t *))(&__kmp_set_queuing_lock_location); __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_flags); __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))( &__kmp_set_queuing_lock_flags); } break; #if KMP_USE_ADAPTIVE_LOCKS case lk_adaptive: { __kmp_base_user_lock_size = sizeof(kmp_base_adaptive_lock_t); __kmp_user_lock_size = sizeof(kmp_adaptive_lock_t); __kmp_get_user_lock_owner_ = (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_owner); if (__kmp_env_consistency_check) { KMP_BIND_USER_LOCK_WITH_CHECKS(adaptive); } else { KMP_BIND_USER_LOCK(adaptive); } __kmp_destroy_user_lock_ = (void (*)(kmp_user_lock_p))(&__kmp_destroy_adaptive_lock); __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))(&__kmp_is_queuing_lock_initialized); __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_location); __kmp_set_user_lock_location_ = (void (*)( kmp_user_lock_p, const ident_t *))(&__kmp_set_queuing_lock_location); __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_queuing_lock_flags); __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))( &__kmp_set_queuing_lock_flags); } break; #endif // KMP_USE_ADAPTIVE_LOCKS case lk_drdpa: { __kmp_base_user_lock_size = sizeof(kmp_base_drdpa_lock_t); __kmp_user_lock_size = sizeof(kmp_drdpa_lock_t); __kmp_get_user_lock_owner_ = (kmp_int32(*)(kmp_user_lock_p))(&__kmp_get_drdpa_lock_owner); if (__kmp_env_consistency_check) { KMP_BIND_USER_LOCK_WITH_CHECKS(drdpa); KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(drdpa); } else { KMP_BIND_USER_LOCK(drdpa); KMP_BIND_NESTED_USER_LOCK(drdpa); } __kmp_destroy_user_lock_ = (void (*)(kmp_user_lock_p))(&__kmp_destroy_drdpa_lock); __kmp_is_user_lock_initialized_ = (int (*)(kmp_user_lock_p))(&__kmp_is_drdpa_lock_initialized); __kmp_get_user_lock_location_ = (const ident_t *(*)(kmp_user_lock_p))(&__kmp_get_drdpa_lock_location); __kmp_set_user_lock_location_ = (void (*)( kmp_user_lock_p, const ident_t *))(&__kmp_set_drdpa_lock_location); __kmp_get_user_lock_flags_ = (kmp_lock_flags_t(*)(kmp_user_lock_p))(&__kmp_get_drdpa_lock_flags); __kmp_set_user_lock_flags_ = (void (*)(kmp_user_lock_p, kmp_lock_flags_t))( &__kmp_set_drdpa_lock_flags); } break; } } // ---------------------------------------------------------------------------- // User lock table & lock allocation kmp_lock_table_t __kmp_user_lock_table = {1, 0, NULL}; kmp_user_lock_p __kmp_lock_pool = NULL; // Lock block-allocation support. kmp_block_of_locks *__kmp_lock_blocks = NULL; int __kmp_num_locks_in_block = 1; // FIXME - tune this value static kmp_lock_index_t __kmp_lock_table_insert(kmp_user_lock_p lck) { // Assume that kmp_global_lock is held upon entry/exit. kmp_lock_index_t index; if (__kmp_user_lock_table.used >= __kmp_user_lock_table.allocated) { kmp_lock_index_t size; kmp_user_lock_p *table; // Reallocate lock table. if (__kmp_user_lock_table.allocated == 0) { size = 1024; } else { size = __kmp_user_lock_table.allocated * 2; } table = (kmp_user_lock_p *)__kmp_allocate(sizeof(kmp_user_lock_p) * size); KMP_MEMCPY(table + 1, __kmp_user_lock_table.table + 1, sizeof(kmp_user_lock_p) * (__kmp_user_lock_table.used - 1)); table[0] = (kmp_user_lock_p)__kmp_user_lock_table.table; // We cannot free the previous table now, since it may be in use by other // threads. So save the pointer to the previous table in in the first // element of the new table. All the tables will be organized into a list, // and could be freed when library shutting down. __kmp_user_lock_table.table = table; __kmp_user_lock_table.allocated = size; } KMP_DEBUG_ASSERT(__kmp_user_lock_table.used < __kmp_user_lock_table.allocated); index = __kmp_user_lock_table.used; __kmp_user_lock_table.table[index] = lck; ++__kmp_user_lock_table.used; return index; } static kmp_user_lock_p __kmp_lock_block_allocate() { // Assume that kmp_global_lock is held upon entry/exit. static int last_index = 0; if ((last_index >= __kmp_num_locks_in_block) || (__kmp_lock_blocks == NULL)) { // Restart the index. last_index = 0; // Need to allocate a new block. KMP_DEBUG_ASSERT(__kmp_user_lock_size > 0); size_t space_for_locks = __kmp_user_lock_size * __kmp_num_locks_in_block; char *buffer = (char *)__kmp_allocate(space_for_locks + sizeof(kmp_block_of_locks)); // Set up the new block. kmp_block_of_locks *new_block = (kmp_block_of_locks *)(&buffer[space_for_locks]); new_block->next_block = __kmp_lock_blocks; new_block->locks = (void *)buffer; // Publish the new block. KMP_MB(); __kmp_lock_blocks = new_block; } kmp_user_lock_p ret = (kmp_user_lock_p)(&( ((char *)(__kmp_lock_blocks->locks))[last_index * __kmp_user_lock_size])); last_index++; return ret; } // Get memory for a lock. It may be freshly allocated memory or reused memory // from lock pool. kmp_user_lock_p __kmp_user_lock_allocate(void **user_lock, kmp_int32 gtid, kmp_lock_flags_t flags) { kmp_user_lock_p lck; kmp_lock_index_t index; KMP_DEBUG_ASSERT(user_lock); __kmp_acquire_lock(&__kmp_global_lock, gtid); if (__kmp_lock_pool == NULL) { // Lock pool is empty. Allocate new memory. if (__kmp_num_locks_in_block <= 1) { // Tune this cutoff point. lck = (kmp_user_lock_p)__kmp_allocate(__kmp_user_lock_size); } else { lck = __kmp_lock_block_allocate(); } // Insert lock in the table so that it can be freed in __kmp_cleanup, // and debugger has info on all allocated locks. index = __kmp_lock_table_insert(lck); } else { // Pick up lock from pool. lck = __kmp_lock_pool; index = __kmp_lock_pool->pool.index; __kmp_lock_pool = __kmp_lock_pool->pool.next; } // We could potentially differentiate between nested and regular locks // here, and do the lock table lookup for regular locks only. if (OMP_LOCK_T_SIZE < sizeof(void *)) { *((kmp_lock_index_t *)user_lock) = index; } else { *((kmp_user_lock_p *)user_lock) = lck; } // mark the lock if it is critical section lock. __kmp_set_user_lock_flags(lck, flags); __kmp_release_lock(&__kmp_global_lock, gtid); // AC: TODO move this line upper return lck; } // Put lock's memory to pool for reusing. void __kmp_user_lock_free(void **user_lock, kmp_int32 gtid, kmp_user_lock_p lck) { KMP_DEBUG_ASSERT(user_lock != NULL); KMP_DEBUG_ASSERT(lck != NULL); __kmp_acquire_lock(&__kmp_global_lock, gtid); lck->pool.next = __kmp_lock_pool; __kmp_lock_pool = lck; if (OMP_LOCK_T_SIZE < sizeof(void *)) { kmp_lock_index_t index = *((kmp_lock_index_t *)user_lock); KMP_DEBUG_ASSERT(0 < index && index <= __kmp_user_lock_table.used); lck->pool.index = index; } __kmp_release_lock(&__kmp_global_lock, gtid); } kmp_user_lock_p __kmp_lookup_user_lock(void **user_lock, char const *func) { kmp_user_lock_p lck = NULL; if (__kmp_env_consistency_check) { if (user_lock == NULL) { KMP_FATAL(LockIsUninitialized, func); } } if (OMP_LOCK_T_SIZE < sizeof(void *)) { kmp_lock_index_t index = *((kmp_lock_index_t *)user_lock); if (__kmp_env_consistency_check) { if (!(0 < index && index < __kmp_user_lock_table.used)) { KMP_FATAL(LockIsUninitialized, func); } } KMP_DEBUG_ASSERT(0 < index && index < __kmp_user_lock_table.used); KMP_DEBUG_ASSERT(__kmp_user_lock_size > 0); lck = __kmp_user_lock_table.table[index]; } else { lck = *((kmp_user_lock_p *)user_lock); } if (__kmp_env_consistency_check) { if (lck == NULL) { KMP_FATAL(LockIsUninitialized, func); } } return lck; } void __kmp_cleanup_user_locks(void) { // Reset lock pool. Don't worry about lock in the pool--we will free them when // iterating through lock table (it includes all the locks, dead or alive). __kmp_lock_pool = NULL; #define IS_CRITICAL(lck) \ ((__kmp_get_user_lock_flags_ != NULL) && \ ((*__kmp_get_user_lock_flags_)(lck)&kmp_lf_critical_section)) // Loop through lock table, free all locks. // Do not free item [0], it is reserved for lock tables list. // // FIXME - we are iterating through a list of (pointers to) objects of type // union kmp_user_lock, but we have no way of knowing whether the base type is // currently "pool" or whatever the global user lock type is. // // We are relying on the fact that for all of the user lock types // (except "tas"), the first field in the lock struct is the "initialized" // field, which is set to the address of the lock object itself when // the lock is initialized. When the union is of type "pool", the // first field is a pointer to the next object in the free list, which // will not be the same address as the object itself. // // This means that the check (*__kmp_is_user_lock_initialized_)(lck) will fail // for "pool" objects on the free list. This must happen as the "location" // field of real user locks overlaps the "index" field of "pool" objects. // // It would be better to run through the free list, and remove all "pool" // objects from the lock table before executing this loop. However, // "pool" objects do not always have their index field set (only on // lin_32e), and I don't want to search the lock table for the address // of every "pool" object on the free list. while (__kmp_user_lock_table.used > 1) { const ident *loc; // reduce __kmp_user_lock_table.used before freeing the lock, // so that state of locks is consistent kmp_user_lock_p lck = __kmp_user_lock_table.table[--__kmp_user_lock_table.used]; if ((__kmp_is_user_lock_initialized_ != NULL) && (*__kmp_is_user_lock_initialized_)(lck)) { // Issue a warning if: KMP_CONSISTENCY_CHECK AND lock is initialized AND // it is NOT a critical section (user is not responsible for destroying // criticals) AND we know source location to report. if (__kmp_env_consistency_check && (!IS_CRITICAL(lck)) && ((loc = __kmp_get_user_lock_location(lck)) != NULL) && (loc->psource != NULL)) { kmp_str_loc_t str_loc = __kmp_str_loc_init(loc->psource, false); KMP_WARNING(CnsLockNotDestroyed, str_loc.file, str_loc.line); __kmp_str_loc_free(&str_loc); } #ifdef KMP_DEBUG if (IS_CRITICAL(lck)) { KA_TRACE( 20, ("__kmp_cleanup_user_locks: free critical section lock %p (%p)\n", lck, *(void **)lck)); } else { KA_TRACE(20, ("__kmp_cleanup_user_locks: free lock %p (%p)\n", lck, *(void **)lck)); } #endif // KMP_DEBUG // Cleanup internal lock dynamic resources (for drdpa locks particularly). __kmp_destroy_user_lock(lck); } // Free the lock if block allocation of locks is not used. if (__kmp_lock_blocks == NULL) { __kmp_free(lck); } } #undef IS_CRITICAL // delete lock table(s). kmp_user_lock_p *table_ptr = __kmp_user_lock_table.table; __kmp_user_lock_table.table = NULL; __kmp_user_lock_table.allocated = 0; while (table_ptr != NULL) { // In the first element we saved the pointer to the previous // (smaller) lock table. kmp_user_lock_p *next = (kmp_user_lock_p *)(table_ptr[0]); __kmp_free(table_ptr); table_ptr = next; } // Free buffers allocated for blocks of locks. kmp_block_of_locks_t *block_ptr = __kmp_lock_blocks; __kmp_lock_blocks = NULL; while (block_ptr != NULL) { kmp_block_of_locks_t *next = block_ptr->next_block; __kmp_free(block_ptr->locks); // *block_ptr itself was allocated at the end of the locks vector. block_ptr = next; } TCW_4(__kmp_init_user_locks, FALSE); } #endif // KMP_USE_DYNAMIC_LOCK