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author | Hirokazu Takata <takata@linux-m32r.org> | 2005-11-28 21:43:59 (GMT) |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-28 22:42:24 (GMT) |
commit | 0332db5aff3eec73eead6d991782b0dee1376dc0 (patch) | |
tree | bc3299c3be9f5a64591dbe1a3ab5b86991c847b3 /include/asm-m32r/atomic.h | |
parent | 91f4ab056d85d23fa6955927fdeb1558673e8cd1 (diff) | |
download | linux-0332db5aff3eec73eead6d991782b0dee1376dc0.tar.xz |
[PATCH] m32r: Introduce atomic_cmpxchg and atomic_inc_not_zero operations
Introduce atomic_cmpxchg and atomic_inc_not_zero operations for m32r.
Signed-off-by: Hayato Fujiwara <fujiwara@linux-m32r.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/asm-m32r/atomic.h')
-rw-r--r-- | include/asm-m32r/atomic.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/include/asm-m32r/atomic.h b/include/asm-m32r/atomic.h index bfff69a..ef1fb8e 100644 --- a/include/asm-m32r/atomic.h +++ b/include/asm-m32r/atomic.h @@ -242,6 +242,27 @@ static __inline__ int atomic_dec_return(atomic_t *v) */ #define atomic_add_negative(i,v) (atomic_add_return((i), (v)) < 0) +#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n))) + +/** + * atomic_add_unless - add unless the number is a given value + * @v: pointer of type atomic_t + * @a: the amount to add to v... + * @u: ...unless v is equal to u. + * + * Atomically adds @a to @v, so long as it was not @u. + * Returns non-zero if @v was not @u, and zero otherwise. + */ +#define atomic_add_unless(v, a, u) \ +({ \ + int c, old; \ + c = atomic_read(v); \ + while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \ + c = old; \ + c != (u); \ +}) +#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) + static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t *addr) { unsigned long flags; |