Home | History | Annotate | Line # | Download | only in atomic 
      1 /*	$NetBSD: atomic_add_64_cas.c,v 1.9 2014/06/23 21:53:45 joerg Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2007 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jason R. Thorpe.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include "atomic_op_namespace.h"
     33 
     34 #include <sys/atomic.h>
     35 
     36 #ifdef __HAVE_ATOMIC64_OPS
     37 
     38 uint64_t fetch_and_add_8(volatile uint64_t *, uint64_t, ...)
     39     asm("__sync_fetch_and_add_8");
     40 
     41 uint64_t
     42 fetch_and_add_8(volatile uint64_t *addr, uint64_t val, ...)
     43 {
     44 	uint64_t old, new;
     45 
     46 	do {
     47 		old = *addr;
     48 		new = old + val;
     49 	} while (atomic_cas_64(addr, old, new) != old);
     50 	return old;
     51 }
     52 
     53 void
     54 atomic_add_64(volatile uint64_t *addr, int64_t val)
     55 {
     56    (void) fetch_and_add_8(addr, val);
     57 }
     58 
     59 __strong_alias(__atomic_fetch_add_8,__sync_fetch_and_add_8)
     60 
     61 #undef atomic_add_64
     62 atomic_op_alias(atomic_add_64,_atomic_add_64)
     63 
     64 #if defined(_LP64)
     65 #undef atomic_add_long
     66 atomic_op_alias(atomic_add_long,_atomic_add_64)
     67 __strong_alias(_atomic_add_long,_atomic_add_64)
     68 
     69 #undef atomic_add_ptr
     70 atomic_op_alias(atomic_add_ptr,_atomic_add_64)
     71 __strong_alias(_atomic_add_ptr,_atomic_add_64)
     72 #endif /* _LP64 */
     73 
     74 #endif
     75