1*f6217f89SApple OSS Distributions /*
2*f6217f89SApple OSS Distributions * Copyright (c) 2020 Apple Computer, Inc. All rights reserved.
3*f6217f89SApple OSS Distributions *
4*f6217f89SApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*f6217f89SApple OSS Distributions *
6*f6217f89SApple OSS Distributions * This file contains Original Code and/or Modifications of Original Code
7*f6217f89SApple OSS Distributions * as defined in and that are subject to the Apple Public Source License
8*f6217f89SApple OSS Distributions * Version 2.0 (the 'License'). You may not use this file except in
9*f6217f89SApple OSS Distributions * compliance with the License. The rights granted to you under the License
10*f6217f89SApple OSS Distributions * may not be used to create, or enable the creation or redistribution of,
11*f6217f89SApple OSS Distributions * unlawful or unlicensed copies of an Apple operating system, or to
12*f6217f89SApple OSS Distributions * circumvent, violate, or enable the circumvention or violation of, any
13*f6217f89SApple OSS Distributions * terms of an Apple operating system software license agreement.
14*f6217f89SApple OSS Distributions *
15*f6217f89SApple OSS Distributions * Please obtain a copy of the License at
16*f6217f89SApple OSS Distributions * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*f6217f89SApple OSS Distributions *
18*f6217f89SApple OSS Distributions * The Original Code and all software distributed under the License are
19*f6217f89SApple OSS Distributions * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*f6217f89SApple OSS Distributions * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*f6217f89SApple OSS Distributions * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*f6217f89SApple OSS Distributions * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*f6217f89SApple OSS Distributions * Please see the License for the specific language governing rights and
24*f6217f89SApple OSS Distributions * limitations under the License.
25*f6217f89SApple OSS Distributions *
26*f6217f89SApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*f6217f89SApple OSS Distributions */
28*f6217f89SApple OSS Distributions
29*f6217f89SApple OSS Distributions #include <libkern/OSAtomic.h>
30*f6217f89SApple OSS Distributions #include <machine/atomic.h>
31*f6217f89SApple OSS Distributions
32*f6217f89SApple OSS Distributions _Static_assert(sizeof(int) == sizeof(OSSpinLock), "OSSpinLock size mismatch");
33*f6217f89SApple OSS Distributions
34*f6217f89SApple OSS Distributions void
OSSpinLockUnlock(volatile OSSpinLock * lock)35*f6217f89SApple OSS Distributions OSSpinLockUnlock(volatile OSSpinLock *lock)
36*f6217f89SApple OSS Distributions {
37*f6217f89SApple OSS Distributions os_atomic_store(lock, 0, release);
38*f6217f89SApple OSS Distributions }
39*f6217f89SApple OSS Distributions
40*f6217f89SApple OSS Distributions Boolean
OSSpinLockTry(volatile OSSpinLock * lock)41*f6217f89SApple OSS Distributions OSSpinLockTry(volatile OSSpinLock *lock)
42*f6217f89SApple OSS Distributions {
43*f6217f89SApple OSS Distributions return os_atomic_cmpxchg(lock, 0, 1, acquire);
44*f6217f89SApple OSS Distributions }
45