11dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* 21dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Copyright (C) 2008 The Android Open Source Project 31dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * All rights reserved. 41dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 51dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Redistribution and use in source and binary forms, with or without 61dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * modification, are permitted provided that the following conditions 71dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * are met: 81dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * * Redistributions of source code must retain the above copyright 91dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * notice, this list of conditions and the following disclaimer. 101dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * * Redistributions in binary form must reproduce the above copyright 111dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * notice, this list of conditions and the following disclaimer in 121dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * the documentation and/or other materials provided with the 131dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * distribution. 141dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 151dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 161dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 171dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 181dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 191dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 201dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 211dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 221dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 231dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 241dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 251dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 261dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * SUCH DAMAGE. 271dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 281dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#ifndef _SYS_ATOMICS_H 291dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#define _SYS_ATOMICS_H 301dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 311dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <sys/cdefs.h> 321dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <sys/time.h> 331dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 341dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project__BEGIN_DECLS 351dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 360fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner/* Note: atomic operations that were exported by the C library didn't 370fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * provide any memory barriers, which created potential issues on 380fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * multi-core devices. We now define them as inlined calls to 390fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * GCC sync builtins, which always provide a full barrier. 400fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * 410fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * NOTE: The C library still exports atomic functions by the same 420fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * name to ensure ABI stability for existing NDK machine code. 430fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * 440fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * If you are an NDK developer, we encourage you to rebuild your 450fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner * unmodified sources against this header as soon as possible. 460fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner */ 470fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner#define __ATOMIC_INLINE__ static __inline__ __attribute__((always_inline)) 480fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner 490fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner__ATOMIC_INLINE__ int 50958dad705a8c2c191e4352547fc9950c4feaa9fbChris Dearman__atomic_cmpxchg(int old_value, int new_value, volatile int* ptr) 510fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner{ 520fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner /* We must return 0 on success */ 53958dad705a8c2c191e4352547fc9950c4feaa9fbChris Dearman return __sync_val_compare_and_swap(ptr, old_value, new_value) != old_value; 540fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner} 550fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner 560fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner__ATOMIC_INLINE__ int 57958dad705a8c2c191e4352547fc9950c4feaa9fbChris Dearman__atomic_swap(int new_value, volatile int *ptr) 580fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner{ 59958dad705a8c2c191e4352547fc9950c4feaa9fbChris Dearman int old_value; 600fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner do { 61958dad705a8c2c191e4352547fc9950c4feaa9fbChris Dearman old_value = *ptr; 62958dad705a8c2c191e4352547fc9950c4feaa9fbChris Dearman } while (__sync_val_compare_and_swap(ptr, old_value, new_value) != old_value); 63958dad705a8c2c191e4352547fc9950c4feaa9fbChris Dearman return old_value; 640fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner} 650fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner 660fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner__ATOMIC_INLINE__ int 670fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner__atomic_dec(volatile int *ptr) 680fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner{ 690fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner return __sync_fetch_and_sub (ptr, 1); 700fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner} 710fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner 720fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner__ATOMIC_INLINE__ int 730fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner__atomic_inc(volatile int *ptr) 740fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner{ 750fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner return __sync_fetch_and_add (ptr, 1); 760fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner} 770fec6b9d88ee5a9e359b2208038f9806c0804538David 'Digit' Turner 781dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 791dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint __futex_wait(volatile void *ftx, int val, const struct timespec *timeout); 801dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint __futex_wake(volatile void *ftx, int count); 811dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 821dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project__END_DECLS 831dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 841dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#endif /* _SYS_ATOMICS_H */ 85