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/*-
* Copyright (c) 2010 Isilon Systems, Inc.
* Copyright (c) 2010 iX Systems, Inc.
* Copyright (c) 2010 Panasas, Inc.
* Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _ASM_ATOMIC_H_
#define _ASM_ATOMIC_H_
#include <sys/cdefs.h>
#include <sys/types.h>
#include <machine/atomic.h>
#define ATOMIC_INIT(x) { .counter = (x) }
typedef struct {
volatile int counter;
} atomic_t;
/*------------------------------------------------------------------------*
* 32-bit atomic operations
*------------------------------------------------------------------------*/
#define atomic_add(i, v) atomic_add_return((i), (v))
#define atomic_sub(i, v) atomic_sub_return((i), (v))
#define atomic_inc_return(v) atomic_add_return(1, (v))
#define atomic_add_negative(i, v) (atomic_add_return((i), (v)) < 0)
#define atomic_add_and_test(i, v) (atomic_add_return((i), (v)) == 0)
#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
#define atomic_dec_return(v) atomic_sub_return(1, (v))
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
static inline int
atomic_add_return(int i, atomic_t *v)
{
return i + atomic_fetchadd_int(&v->counter, i);
}
static inline int
atomic_sub_return(int i, atomic_t *v)
{
return atomic_fetchadd_int(&v->counter, -i) - i;
}
static inline void
atomic_set(atomic_t *v, int i)
{
atomic_store_rel_int(&v->counter, i);
}
static inline void
atomic_set_mask(unsigned int mask, atomic_t *v)
{
atomic_set_int(&v->counter, mask);
}
static inline int
atomic_read(atomic_t *v)
{
return atomic_load_acq_int(&v->counter);
}
static inline int
atomic_inc(atomic_t *v)
{
return atomic_fetchadd_int(&v->counter, 1) + 1;
}
static inline int
atomic_dec(atomic_t *v)
{
return atomic_fetchadd_int(&v->counter, -1) - 1;
}
static inline int
atomic_add_unless(atomic_t *v, int a, int u)
{
int c;
for (;;) {
c = atomic_read(v);
if (unlikely(c == u))
break;
if (likely(atomic_cmpset_int(&v->counter, c, c + a)))
break;
}
return (c != u);
}
static inline void
atomic_clear_mask(unsigned int mask, atomic_t *v)
{
atomic_clear_int(&v->counter, mask);
}
static inline int
atomic_xchg(atomic_t *v, int i)
{
#if defined(__i386__) || defined(__amd64__) || \
defined(__arm__) || defined(__aarch64__)
return (atomic_swap_int(&v->counter, i));
#else
int ret;
for (;;) {
ret = atomic_load_acq_int(&v->counter);
if (atomic_cmpset_int(&v->counter, ret, i))
break;
}
return (ret);
#endif
}
static inline int
atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret = old;
for (;;) {
if (atomic_cmpset_int(&v->counter, old, new))
break;
ret = atomic_load_acq_int(&v->counter);
if (ret != old)
break;
}
return (ret);
}
#define cmpxchg(ptr, old, new) ({ \
__typeof(*(ptr)) __ret = (old); \
CTASSERT(sizeof(__ret) == 4 || sizeof(__ret) == 8); \
for (;;) { \
if (sizeof(__ret) == 4) { \
if (atomic_cmpset_int((volatile int *) \
(ptr), (old), (new))) \
break; \
__ret = atomic_load_acq_int( \
(volatile int *)(ptr)); \
if (__ret != (old)) \
break; \
} else { \
if (atomic_cmpset_64( \
(volatile int64_t *)(ptr), \
(old), (new))) \
break; \
__ret = atomic_load_acq_64( \
(volatile int64_t *)(ptr)); \
if (__ret != (old)) \
break; \
} \
} \
__ret; \
})
#define LINUX_ATOMIC_OP(op, c_op) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
int c, old; \
\
c = v->counter; \
while ((old = atomic_cmpxchg(v, c, c c_op i)) != c) \
c = old; \
}
LINUX_ATOMIC_OP(or, |)
LINUX_ATOMIC_OP(and, &)
LINUX_ATOMIC_OP(xor, ^)
#endif /* _ASM_ATOMIC_H_ */
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