aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-v850/atomic.h
diff options
context:
space:
mode:
authorNick Piggin <nickpiggin@yahoo.com.au>2005-11-13 19:07:24 -0500
committerLinus Torvalds <torvalds@g5.osdl.org>2005-11-13 21:14:16 -0500
commit4a6dae6d382e9edf3ff440b819e554ed706359bc (patch)
tree2945a5095973e2ecf05b503d6deb859083045b8e /include/asm-v850/atomic.h
parent53e86b91b7ae66d4c2757195cbd42e00d9199cf2 (diff)
[PATCH] atomic: cmpxchg
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>
Diffstat (limited to 'include/asm-v850/atomic.h')
-rw-r--r--include/asm-v850/atomic.h14
1 files changed, 14 insertions, 0 deletions
diff --git a/include/asm-v850/atomic.h b/include/asm-v850/atomic.h
index 395268a8c0de..e497166ca42b 100644
--- a/include/asm-v850/atomic.h
+++ b/include/asm-v850/atomic.h
@@ -90,6 +90,20 @@ static __inline__ void atomic_clear_mask (unsigned long mask, unsigned long *add
90#define atomic_dec_and_test(v) (atomic_sub_return (1, (v)) == 0) 90#define atomic_dec_and_test(v) (atomic_sub_return (1, (v)) == 0)
91#define atomic_add_negative(i,v) (atomic_add_return ((i), (v)) < 0) 91#define atomic_add_negative(i,v) (atomic_add_return ((i), (v)) < 0)
92 92
93static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
94{
95 int ret;
96 unsigned long flags;
97
98 local_irq_save(flags);
99 ret = v->counter;
100 if (likely(ret == old))
101 v->counter = new;
102 local_irq_restore(flags);
103
104 return ret;
105}
106
93/* Atomic operations are already serializing on ARM */ 107/* Atomic operations are already serializing on ARM */
94#define smp_mb__before_atomic_dec() barrier() 108#define smp_mb__before_atomic_dec() barrier()
95#define smp_mb__after_atomic_dec() barrier() 109#define smp_mb__after_atomic_dec() barrier()