1 /* 2 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // Implementation of class OrderAccess. 26 27 // For Sun Studio - implementation is in solaris_i486.il. 28 // For gcc - implementation is just below. 29 extern "C" void _OrderAccess_acquire(); 30 extern "C" void _OrderAccess_fence(); 31 32 inline void OrderAccess::loadload() { acquire(); } 33 inline void OrderAccess::storestore() { release(); } 34 inline void OrderAccess::loadstore() { acquire(); } 35 inline void OrderAccess::storeload() { fence(); } 36 37 inline void OrderAccess::acquire() { 38 _OrderAccess_acquire(); 39 40 } 41 42 inline void OrderAccess::release() { 43 // Avoid hitting the same cache-line from 44 // different threads. 45 volatile jint local_dummy = 0; 46 } 47 48 inline void OrderAccess::fence() { 49 if (os::is_MP()) { 50 _OrderAccess_fence(); 51 } 52 } 53 54 #ifdef _GNU_SOURCE 55 56 extern "C" { 57 inline void _OrderAccess_acquire() { 58 volatile intptr_t local_dummy; 59 #ifdef AMD64 60 __asm__ volatile ("movq 0(%%rsp), %0" : "=r" (local_dummy) : : "memory"); 61 #else 62 __asm__ volatile ("movl 0(%%esp),%0" : "=r" (local_dummy) : : "memory"); 63 #endif // AMD64 64 } 65 inline void _OrderAccess_fence() { 66 // Always use locked addl since mfence is sometimes expensive 67 __asm__ volatile ("lock; addl $0,0(%%esp)" : : : "cc", "memory"); 68 } 69 70 } 71 72 #endif // GNU_SOURCE 73 74 inline jbyte OrderAccess::load_acquire(volatile jbyte* p) { return *p; } 75 inline jshort OrderAccess::load_acquire(volatile jshort* p) { return *p; } 76 inline jint OrderAccess::load_acquire(volatile jint* p) { return *p; } 77 inline jlong OrderAccess::load_acquire(volatile jlong* p) { return *p; } 78 inline jubyte OrderAccess::load_acquire(volatile jubyte* p) { return *p; } 79 inline jushort OrderAccess::load_acquire(volatile jushort* p) { return *p; } 80 inline juint OrderAccess::load_acquire(volatile juint* p) { return *p; } 81 inline julong OrderAccess::load_acquire(volatile julong* p) { return *p; } 82 inline jfloat OrderAccess::load_acquire(volatile jfloat* p) { return *p; } 83 inline jdouble OrderAccess::load_acquire(volatile jdouble* p) { return *p; } 84 85 inline intptr_t OrderAccess::load_ptr_acquire(volatile intptr_t* p) { return *p; } 86 inline void* OrderAccess::load_ptr_acquire(volatile void* p) { return *(void* volatile *)p; } 87 inline void* OrderAccess::load_ptr_acquire(const volatile void* p) { return *(void* const volatile *)p; } 88 89 inline void OrderAccess::release_store(volatile jbyte* p, jbyte v) { *p = v; } 90 inline void OrderAccess::release_store(volatile jshort* p, jshort v) { *p = v; } 91 inline void OrderAccess::release_store(volatile jint* p, jint v) { *p = v; } 92 inline void OrderAccess::release_store(volatile jlong* p, jlong v) { *p = v; } 93 inline void OrderAccess::release_store(volatile jubyte* p, jubyte v) { *p = v; } 94 inline void OrderAccess::release_store(volatile jushort* p, jushort v) { *p = v; } 95 inline void OrderAccess::release_store(volatile juint* p, juint v) { *p = v; } 96 inline void OrderAccess::release_store(volatile julong* p, julong v) { *p = v; } 97 inline void OrderAccess::release_store(volatile jfloat* p, jfloat v) { *p = v; } 98 inline void OrderAccess::release_store(volatile jdouble* p, jdouble v) { *p = v; } 99 100 inline void OrderAccess::release_store_ptr(volatile intptr_t* p, intptr_t v) { *p = v; } 101 inline void OrderAccess::release_store_ptr(volatile void* p, void* v) { *(void* volatile *)p = v; } 102 103 inline void OrderAccess::store_fence(jbyte* p, jbyte v) { *p = v; fence(); } 104 inline void OrderAccess::store_fence(jshort* p, jshort v) { *p = v; fence(); } 105 inline void OrderAccess::store_fence(jint* p, jint v) { *p = v; fence(); } 106 inline void OrderAccess::store_fence(jlong* p, jlong v) { *p = v; fence(); } 107 inline void OrderAccess::store_fence(jubyte* p, jubyte v) { *p = v; fence(); } 108 inline void OrderAccess::store_fence(jushort* p, jushort v) { *p = v; fence(); } 109 inline void OrderAccess::store_fence(juint* p, juint v) { *p = v; fence(); } 110 inline void OrderAccess::store_fence(julong* p, julong v) { *p = v; fence(); } 111 inline void OrderAccess::store_fence(jfloat* p, jfloat v) { *p = v; fence(); } 112 inline void OrderAccess::store_fence(jdouble* p, jdouble v) { *p = v; fence(); } 113 114 inline void OrderAccess::store_ptr_fence(intptr_t* p, intptr_t v) { *p = v; fence(); } 115 inline void OrderAccess::store_ptr_fence(void** p, void* v) { *p = v; fence(); } 116 117 inline void OrderAccess::release_store_fence(volatile jbyte* p, jbyte v) { *p = v; fence(); } 118 inline void OrderAccess::release_store_fence(volatile jshort* p, jshort v) { *p = v; fence(); } 119 inline void OrderAccess::release_store_fence(volatile jint* p, jint v) { *p = v; fence(); } 120 inline void OrderAccess::release_store_fence(volatile jlong* p, jlong v) { *p = v; fence(); } 121 inline void OrderAccess::release_store_fence(volatile jubyte* p, jubyte v) { *p = v; fence(); } 122 inline void OrderAccess::release_store_fence(volatile jushort* p, jushort v) { *p = v; fence(); } 123 inline void OrderAccess::release_store_fence(volatile juint* p, juint v) { *p = v; fence(); } 124 inline void OrderAccess::release_store_fence(volatile julong* p, julong v) { *p = v; fence(); } 125 inline void OrderAccess::release_store_fence(volatile jfloat* p, jfloat v) { *p = v; fence(); } 126 inline void OrderAccess::release_store_fence(volatile jdouble* p, jdouble v) { *p = v; fence(); } 127 128 inline void OrderAccess::release_store_ptr_fence(volatile intptr_t* p, intptr_t v) { *p = v; fence(); } 129 inline void OrderAccess::release_store_ptr_fence(volatile void* p, void* v) { *(void* volatile *)p = v; fence(); }