1 /*	$NetBSD: atomic_add_32_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 uint32_t fetch_and_add_4(volatile uint32_t *, uint32_t, ...)
37 #if defined(_LIBC) || defined(_HARDKERNEL)
38     asm("__sync_fetch_and_add_4");	/* C runtime internal */
39 #else
40     ;
41 #endif
42 
43 uint32_t
fetch_and_add_4(volatile uint32_t * addr,uint32_t val,...)44 fetch_and_add_4(volatile uint32_t *addr, uint32_t val, ...)
45 {
46 	uint32_t old, new;
47 
48 	do {
49 		old = *addr;
50 		new = old + val;
51 	} while (atomic_cas_32(addr, old, new) != old);
52 	return old;
53 }
54 
55 void
atomic_add_32(volatile uint32_t * addr,int32_t val)56 atomic_add_32(volatile uint32_t *addr, int32_t val)
57 {
58 	(void) fetch_and_add_4(addr, val);
59 }
60 
61 #undef atomic_add_32
62 atomic_op_alias(atomic_add_32,_atomic_add_32)
63 
64 #undef atomic_add_int
65 atomic_op_alias(atomic_add_int,_atomic_add_32)
66 __strong_alias(_atomic_add_int,_atomic_add_32)
67 
68 #if !defined(_LP64)
69 #undef atomic_add_long
70 atomic_op_alias(atomic_add_long,_atomic_add_32)
71 __strong_alias(_atomic_add_long,_atomic_add_32)
72 
73 #undef atomic_add_ptr
74 atomic_op_alias(atomic_add_ptr,_atomic_add_32)
75 __strong_alias(_atomic_add_ptr,_atomic_add_32)
76 #endif /* _LP64 */
77 
78 __strong_alias(__atomic_fetch_add_4,__sync_fetch_and_add_4)
79