1/*
2 * Copyright (C) 2021 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 *     http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16#ifndef SPINLOCK_H
17#define SPINLOCK_H
18
19typedef struct {
20    volatile int lock;
21} Spinlock;
22
23
24#if defined(__x86_64__)
25#include <emmintrin.h>
26
27inline static void Pause(void)
28{
29    _mm_pause();
30}
31#elif defined(RTP_ARCH_ARM)
32static inline void Pause(void)
33{
34    asm volatile("yield" ::: "memory");
35}
36#else
37static inline void Pause(void)
38{
39}
40#endif
41
42static inline void SpinLockInit(Spinlock *spinlock)
43{
44    spinlock->lock = 0;
45}
46
47static inline int SpinLockTryLock(Spinlock *spinlock)
48{
49    if (__sync_bool_compare_and_swap(&spinlock->lock, 0, 1) == 0) {
50        return 0;
51    }
52
53    return 1;
54}
55
56static inline void SpinLock(Spinlock *spinlock)
57{
58    while (!SpinLockTryLock(spinlock)) {
59        do {
60            Pause();
61        } while (!!spinlock->lock);
62    }
63}
64
65static inline void SpinUnlock(Spinlock *spinlock)
66{
67    __sync_lock_release(&spinlock->lock);
68}
69
70#endif /* SPINLOCK_H */
71
72