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Diffstat (limited to 'src/atomic.c')
-rw-r--r-- | src/atomic.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/atomic.c b/src/atomic.c new file mode 100644 index 0000000..cfe1067 --- /dev/null +++ b/src/atomic.c @@ -0,0 +1,68 @@ +/* + * Copyright (c) 2019, The Linux Foundation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * * Neither the name of The Linux Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN + * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#include "AEEatomic.h" + +uint32 atomic_Add(uint32 * volatile puDest, int nAdd) { + uint32 previous; + uint32 current; + do { + current = *puDest; + previous = atomic_CompareAndExchange(puDest, current + nAdd, current); + } while(previous != current); + return (current + nAdd); +} + +uint32 atomic_Exchange(uint32* volatile puDest, uint32 uVal) { + uint32 previous; + uint32 current; + do { + current = *puDest; + previous = atomic_CompareAndExchange(puDest, uVal, current); + } while(previous != current); + return previous; +} + +uint32 atomic_CompareOrAdd(uint32* volatile puDest, uint32 uCompare, int nAdd) { + uint32 previous; + uint32 current; + uint32 result; + do { + current = *puDest; + previous = current; + result = current; + if(current != uCompare) { + previous = atomic_CompareAndExchange(puDest, current + nAdd, current); + if(previous == current) { + result = current + nAdd; + } + } + } while(previous != current); + return result; +} + |