1 /* 2 * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2014, 2019, Red Hat Inc. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #ifndef OS_CPU_LINUX_AARCH64_ATOMIC_LINUX_AARCH64_HPP 27 #define OS_CPU_LINUX_AARCH64_ATOMIC_LINUX_AARCH64_HPP 28 29 #include "runtime/vm_version.hpp" 30 31 // Implementation of class atomic 32 // Note that memory_order_conservative requires a full barrier after atomic stores. 33 // See https://patchwork.kernel.org/patch/3575821/ 34 35 template<size_t byte_size> 36 struct Atomic::PlatformAdd 37 : Atomic::AddAndFetch<Atomic::PlatformAdd<byte_size> > 38 { 39 template<typename I, typename D> 40 D add_and_fetch(I add_value, D volatile* dest, atomic_memory_order order) const { 41 D res = __atomic_add_fetch(dest, add_value, __ATOMIC_RELEASE); 42 FULL_MEM_BARRIER; 43 return res; 44 } 45 }; 46 47 template<size_t byte_size> 48 template<typename T> 49 inline T Atomic::PlatformXchg<byte_size>::operator()(T exchange_value, 50 T volatile* dest, 51 atomic_memory_order order) const { 52 STATIC_ASSERT(byte_size == sizeof(T)); 53 T res = __atomic_exchange_n(dest, exchange_value, __ATOMIC_RELEASE); 54 FULL_MEM_BARRIER; 55 return res; 56 } 57 58 template<size_t byte_size> 59 template<typename T> 60 inline T Atomic::PlatformCmpxchg<byte_size>::operator()(T exchange_value, 61 T volatile* dest, 62 T compare_value, 63 atomic_memory_order order) const { 64 STATIC_ASSERT(byte_size == sizeof(T)); 65 if (order == memory_order_relaxed) { 66 T value = compare_value; 67 __atomic_compare_exchange(dest, &value, &exchange_value, /*weak*/false, 68 __ATOMIC_RELAXED, __ATOMIC_RELAXED); 69 return value; 70 } else { 71 T value = compare_value; 72 FULL_MEM_BARRIER; 73 __atomic_compare_exchange(dest, &value, &exchange_value, /*weak*/false, 74 __ATOMIC_RELAXED, __ATOMIC_RELAXED); 75 FULL_MEM_BARRIER; 76 return value; 77 } 78 } 79 80 template<size_t byte_size> 81 struct Atomic::PlatformOrderedLoad<byte_size, X_ACQUIRE> 82 { 83 template <typename T> 84 T operator()(const volatile T* p) const { T data; __atomic_load(const_cast<T*>(p), &data, __ATOMIC_ACQUIRE); return data; } 85 }; 86 87 template<size_t byte_size> 88 struct Atomic::PlatformOrderedStore<byte_size, RELEASE_X> 89 { 90 template <typename T> 91 void operator()(T v, volatile T* p) const { __atomic_store(const_cast<T*>(p), &v, __ATOMIC_RELEASE); } 92 }; 93 94 template<size_t byte_size> 95 struct Atomic::PlatformOrderedStore<byte_size, RELEASE_X_FENCE> 96 { 97 template <typename T> 98 void operator()(T v, volatile T* p) const { release_store(p, v); OrderAccess::fence(); } 99 }; 100 101 #endif // OS_CPU_LINUX_AARCH64_ATOMIC_LINUX_AARCH64_HPP