| /* Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "apr_arch_atomic.h" |
| |
| #ifdef USE_ATOMICS_BUILTINS |
| |
| #if defined(__i386__) || defined(__x86_64__) \ |
| || defined(__s390__) || defined(__s390x__) |
| #define WEAK_MEMORY_ORDERING 0 |
| #else |
| #define WEAK_MEMORY_ORDERING 1 |
| #endif |
| |
| APR_DECLARE(apr_status_t) apr_atomic_init(apr_pool_t *p) |
| { |
| #if defined (USE_ATOMICS_GENERIC64) |
| return apr__atomic_generic64_init(p); |
| #else |
| return APR_SUCCESS; |
| #endif |
| } |
| |
| APR_DECLARE(apr_uint32_t) apr_atomic_read32(volatile apr_uint32_t *mem) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| return __atomic_load_n(mem, __ATOMIC_SEQ_CST); |
| #elif WEAK_MEMORY_ORDERING |
| /* No __sync_load() available => apr_atomic_add32(mem, 0) */ |
| return __sync_fetch_and_add(mem, 0); |
| #else |
| return *mem; |
| #endif |
| } |
| |
| APR_DECLARE(void) apr_atomic_set32(volatile apr_uint32_t *mem, apr_uint32_t val) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| __atomic_store_n(mem, val, __ATOMIC_SEQ_CST); |
| #elif WEAK_MEMORY_ORDERING |
| /* No __sync_store() available => apr_atomic_xchg32(mem, val) */ |
| __sync_synchronize(); |
| __sync_lock_test_and_set(mem, val); |
| #else |
| *mem = val; |
| #endif |
| } |
| |
| APR_DECLARE(apr_uint32_t) apr_atomic_add32(volatile apr_uint32_t *mem, apr_uint32_t val) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| return __atomic_fetch_add(mem, val, __ATOMIC_SEQ_CST); |
| #else |
| return __sync_fetch_and_add(mem, val); |
| #endif |
| } |
| |
| APR_DECLARE(void) apr_atomic_sub32(volatile apr_uint32_t *mem, apr_uint32_t val) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| __atomic_fetch_sub(mem, val, __ATOMIC_SEQ_CST); |
| #else |
| __sync_fetch_and_sub(mem, val); |
| #endif |
| } |
| |
| APR_DECLARE(apr_uint32_t) apr_atomic_inc32(volatile apr_uint32_t *mem) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| return __atomic_fetch_add(mem, 1, __ATOMIC_SEQ_CST); |
| #else |
| return __sync_fetch_and_add(mem, 1); |
| #endif |
| } |
| |
| APR_DECLARE(int) apr_atomic_dec32(volatile apr_uint32_t *mem) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| return __atomic_sub_fetch(mem, 1, __ATOMIC_SEQ_CST); |
| #else |
| return __sync_sub_and_fetch(mem, 1); |
| #endif |
| } |
| |
| APR_DECLARE(apr_uint32_t) apr_atomic_cas32(volatile apr_uint32_t *mem, apr_uint32_t val, |
| apr_uint32_t cmp) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| __atomic_compare_exchange_n(mem, &cmp, val, 0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); |
| return cmp; |
| #else |
| return __sync_val_compare_and_swap(mem, cmp, val); |
| #endif |
| } |
| |
| APR_DECLARE(apr_uint32_t) apr_atomic_xchg32(volatile apr_uint32_t *mem, apr_uint32_t val) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| return __atomic_exchange_n(mem, val, __ATOMIC_SEQ_CST); |
| #else |
| __sync_synchronize(); |
| return __sync_lock_test_and_set(mem, val); |
| #endif |
| } |
| |
| APR_DECLARE(void*) apr_atomic_casptr(void *volatile *mem, void *ptr, const void *cmp) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| __atomic_compare_exchange_n(mem, (void *)&cmp, ptr, 0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); |
| return (void *)cmp; |
| #else |
| return (void *)__sync_val_compare_and_swap(mem, (void *)cmp, ptr); |
| #endif |
| } |
| |
| APR_DECLARE(void*) apr_atomic_xchgptr(void *volatile *mem, void *ptr) |
| { |
| #if HAVE__ATOMIC_BUILTINS |
| return __atomic_exchange_n(mem, ptr, __ATOMIC_SEQ_CST); |
| #else |
| __sync_synchronize(); |
| return __sync_lock_test_and_set(mem, ptr); |
| #endif |
| } |
| |
| #endif /* USE_ATOMICS_BUILTINS */ |