2 * Copyright (C) 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
8 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
9 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
10 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
11 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
12 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
13 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
14 * PERFORMANCE OF THIS SOFTWARE.
17 /* $Id: atomic.h,v 1.3 2007/06/19 23:47:18 tbox Exp $ */
20 #define ISC_ATOMIC_H 1
22 #include <isc/platform.h>
23 #include <isc/types.h>
25 #ifdef ISC_PLATFORM_USEGCCASM
27 * This routine atomically increments the value stored in 'p' by 'val', and
28 * returns the previous value.
30 static inline isc_int32_t
31 isc_atomic_xadd(isc_int32_t *p, int val) {
34 /* add is a cheat, since MIPS has no mov instruction */
51 * This routine atomically stores the value 'val' in 'p'.
54 isc_atomic_store(isc_int32_t *p, isc_int32_t val) {
68 * This routine atomically replaces the value in 'p' with 'val', if the
69 * original value is equal to 'cmpval'. The original value is returned in any
72 static inline isc_int32_t
73 isc_atomic_cmpxchg(isc_int32_t *p, int cmpval, int val) {
86 : "m"(*p), "r"(cmpval), "r"(val)
93 #else /* !ISC_PLATFORM_USEGCCASM */
95 #error "unsupported compiler. disable atomic ops by --disable-atomic"
98 #endif /* ISC_ATOMIC_H */