__sync_atomic.h

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/* -*- C -*- */
/*
 * Copyright (c) 2012-2020 Seagate Technology LLC and/or its Affiliates
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * For any questions about this software or licensing,
 * please email opensource@seagate.com or cortx-questions@seagate.com.
 *
 */


#pragma once

#ifndef __MOTR_LIB___SYNC_ATOMIC_H__
#define __MOTR_LIB___SYNC_ATOMIC_H__

#include "lib/types.h"
#include "lib/assert.h"

struct m0_atomic64 {
        long a_value;
};

static inline void m0_atomic64_set(struct m0_atomic64 *a, int64_t num)
{
        M0_CASSERT(sizeof a->a_value == sizeof num);

        a->a_value = num;
}

static inline int64_t m0_atomic64_get(const struct m0_atomic64 *a)
{
        return a->a_value;
}

static inline void m0_atomic64_inc(struct m0_atomic64 *a)
{
        __sync_fetch_and_add(&a->a_value, 1);
}

static inline void m0_atomic64_dec(struct m0_atomic64 *a)
{
        __sync_fetch_and_sub(&a->a_value, 1);
}

static inline void m0_atomic64_add(struct m0_atomic64 *a, int64_t num)
{
        __sync_fetch_and_add(&a->a_value, num);
}

static inline void m0_atomic64_sub(struct m0_atomic64 *a, int64_t num)
{
        __sync_fetch_and_sub(&a->a_value, num);
}

static inline int64_t m0_atomic64_add_return(struct m0_atomic64 *a,
                                             int64_t delta)
{
        return __sync_add_and_fetch(&a->a_value, delta);
}

static inline int64_t m0_atomic64_sub_return(struct m0_atomic64 *a,
                                             int64_t delta)
{
        return m0_atomic64_add_return(a, -delta);
}

static inline bool m0_atomic64_inc_and_test(struct m0_atomic64 *a)
{
        return __sync_add_and_fetch(&a->a_value, 1) == 0;
}

static inline bool m0_atomic64_dec_and_test(struct m0_atomic64 *a)
{
        return __sync_sub_and_fetch(&a->a_value, 1) == 0;
}

static inline bool
m0_atomic64_cas(int64_t * loc, int64_t oldval, int64_t newval)
{
        return __sync_bool_compare_and_swap(loc, oldval, newval);
}

static inline void m0_mb(void)
{
        __sync_synchronize();
}

#endif /* __MOTR_LIB___SYNC_ATOMIC_H__ */

/*
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 *  c-indentation-style: "K&R"
 *  c-basic-offset: 8
 *  tab-width: 8
 *  fill-column: 80
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 *  End:
 */