lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[PATCH] atomic: cmpxchg

Browse Source 
Introduce an atomic_cmpxchg operation.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Nick Piggin
2005-11-13 16:07:24 -08:00
committed by Linus Torvalds
parent 53e86b91b7
commit 4a6dae6d38
23 changed files with 169 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
include/asm-sh/atomic.h
View File

@@ -87,6 +87,20 @@ static __inline__ int atomic_sub_return(int i, atomic_t * v)
#define atomic_inc(v) atomic_add(1,(v))
#define atomic_dec(v) atomic_sub(1,(v))
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret;
unsigned long flags;
local_irq_save(flags);
ret = v->counter;
if (likely(ret == old))
v->counter = new;
local_irq_restore(flags);
return ret;
}
static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
unsigned long flags;