/contrib/bind9/lib/isc/sparc64/include/isc/atomic.h
https://bitbucket.org/freebsd/freebsd-head/ · C Header · 126 lines · 46 code · 19 blank · 61 comment · 6 complexity · 8b086b52cb3475581e90904c108541cc MD5 · raw file
- /*
- * Copyright (C) 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
- *
- * Permission to use, copy, modify, and/or distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
- * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
- * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
- * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
- * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
- * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
- * PERFORMANCE OF THIS SOFTWARE.
- */
- /* $Id: atomic.h,v 1.5 2007/06/19 23:47:18 tbox Exp $ */
- /*
- * This code was written based on FreeBSD's kernel source whose copyright
- * follows:
- */
- /*-
- * Copyright (c) 1998 Doug Rabson.
- * Copyright (c) 2001 Jake Burkholder.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. 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.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 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.
- *
- * from: FreeBSD: src/sys/i386/include/atomic.h,v 1.20 2001/02/11
- * $FreeBSD$
- */
- #ifndef ISC_ATOMIC_H
- #define ISC_ATOMIC_H 1
- #include <isc/platform.h>
- #include <isc/types.h>
- #define ASI_P 0x80 /* Primary Address Space Identifier */
- #ifdef ISC_PLATFORM_USEGCCASM
- /*
- * This routine atomically increments the value stored in 'p' by 'val', and
- * returns the previous value.
- */
- static inline isc_int32_t
- isc_atomic_xadd(isc_int32_t *p, isc_int32_t val) {
- isc_int32_t prev, swapped;
- for (prev = *(volatile isc_int32_t *)p; ; prev = swapped) {
- swapped = prev + val;
- __asm__ volatile(
- "casa [%2] %3, %4, %0"
- : "+r"(swapped), "=m"(*p)
- : "r"(p), "n"(ASI_P), "r"(prev), "m"(*p));
- if (swapped == prev)
- break;
- }
- return (prev);
- }
- /*
- * This routine atomically stores the value 'val' in 'p'.
- */
- static inline void
- isc_atomic_store(isc_int32_t *p, isc_int32_t val) {
- isc_int32_t prev, swapped;
- for (prev = *(volatile isc_int32_t *)p; ; prev = swapped) {
- swapped = val;
- __asm__ volatile(
- "casa [%2] %3, %4, %0"
- : "+r"(swapped), "=m"(*p)
- : "r"(p), "n"(ASI_P), "r"(prev), "m"(*p));
- if (swapped == prev)
- break;
- }
- }
- /*
- * This routine atomically replaces the value in 'p' with 'val', if the
- * original value is equal to 'cmpval'. The original value is returned in any
- * case.
- */
- static inline isc_int32_t
- isc_atomic_cmpxchg(isc_int32_t *p, isc_int32_t cmpval, isc_int32_t val) {
- isc_int32_t temp = val;
- __asm__ volatile(
- "casa [%2] %3, %4, %0"
- : "+r"(temp), "=m"(*p)
- : "r"(p), "n"(ASI_P), "r"(cmpval), "m"(*p));
- return (temp);
- }
- #else /* ISC_PLATFORM_USEGCCASM */
- #error "unsupported compiler. disable atomic ops by --disable-atomic"
- #endif /* ISC_PLATFORM_USEGCCASM */
- #endif /* ISC_ATOMIC_H */