0,0 → 1,97 |
/* |
* Copyright (c) 2005 Jakub Jermar |
* 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. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR 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. |
*/ |
|
/** @addtogroup libcsparc64 |
* @{ |
*/ |
/** @file |
*/ |
|
#ifndef LIBC_sparc64_ATOMIC_H_ |
#define LIBC_sparc64_ATOMIC_H_ |
|
#include <types.h> |
|
/** Atomic add operation. |
* |
* Use atomic compare and swap operation to atomically add signed value. |
* |
* @param val Atomic variable. |
* @param i Signed value to be added. |
* |
* @return Value of the atomic variable as it existed before addition. |
*/ |
static inline long atomic_add(atomic_t *val, int i) |
{ |
uint64_t a, b; |
|
do { |
volatile uintptr_t x = (uint64_t) &val->count; |
|
a = *((uint64_t *) x); |
b = a + i; |
asm volatile ("casx %0, %2, %1\n" : "+m" (*((uint64_t *)x)), "+r" (b) : "r" (a)); |
} while (a != b); |
|
return a; |
} |
|
static inline long atomic_preinc(atomic_t *val) |
{ |
return atomic_add(val, 1) + 1; |
} |
|
static inline long atomic_postinc(atomic_t *val) |
{ |
return atomic_add(val, 1); |
} |
|
static inline long atomic_predec(atomic_t *val) |
{ |
return atomic_add(val, -1) - 1; |
} |
|
static inline long atomic_postdec(atomic_t *val) |
{ |
return atomic_add(val, -1); |
} |
|
static inline void atomic_inc(atomic_t *val) |
{ |
(void) atomic_add(val, 1); |
} |
|
static inline void atomic_dec(atomic_t *val) |
{ |
(void) atomic_add(val, -1); |
} |
|
#endif |
|
/** @} |
*/ |