linux/arch/sparc/include/asm/atomic_32.h
Pranith Kumar 2291059c85 locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read()
Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile.
This is purely a stylistic change.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-03 06:06:23 +02:00

56 lines
1.8 KiB
C

/* atomic.h: These still suck, but the I-cache hit rate is higher.
*
* Copyright (C) 1996 David S. Miller (davem@davemloft.net)
* Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com.au)
* Copyright (C) 2007 Kyle McMartin (kyle@parisc-linux.org)
*
* Additions by Keith M Wesolowski (wesolows@foobazco.org) based
* on asm-parisc/atomic.h Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>.
*/
#ifndef __ARCH_SPARC_ATOMIC__
#define __ARCH_SPARC_ATOMIC__
#include <linux/types.h>
#include <asm/cmpxchg.h>
#include <asm/barrier.h>
#include <asm-generic/atomic64.h>
#define ATOMIC_INIT(i) { (i) }
int atomic_add_return(int, atomic_t *);
int atomic_cmpxchg(atomic_t *, int, int);
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
int __atomic_add_unless(atomic_t *, int, int);
void atomic_set(atomic_t *, int);
#define atomic_read(v) ACCESS_ONCE((v)->counter)
#define atomic_add(i, v) ((void)atomic_add_return( (int)(i), (v)))
#define atomic_sub(i, v) ((void)atomic_add_return(-(int)(i), (v)))
#define atomic_inc(v) ((void)atomic_add_return( 1, (v)))
#define atomic_dec(v) ((void)atomic_add_return( -1, (v)))
#define atomic_sub_return(i, v) (atomic_add_return(-(int)(i), (v)))
#define atomic_inc_return(v) (atomic_add_return( 1, (v)))
#define atomic_dec_return(v) (atomic_add_return( -1, (v)))
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
/*
* atomic_inc_and_test - increment and test
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
#endif /* !(__ARCH_SPARC_ATOMIC__) */