diff options
Diffstat (limited to 'arch/ia64/lib/dec_and_lock.c')
-rw-r--r-- | arch/ia64/lib/dec_and_lock.c | 42 |
1 files changed, 0 insertions, 42 deletions
diff --git a/arch/ia64/lib/dec_and_lock.c b/arch/ia64/lib/dec_and_lock.c deleted file mode 100644 index c7ce92f968f..00000000000 --- a/arch/ia64/lib/dec_and_lock.c +++ /dev/null | |||
@@ -1,42 +0,0 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2003 Jerome Marchand, Bull S.A. | ||
3 | * Cleaned up by David Mosberger-Tang <davidm@hpl.hp.com> | ||
4 | * | ||
5 | * This file is released under the GPLv2, or at your option any later version. | ||
6 | * | ||
7 | * ia64 version of "atomic_dec_and_lock()" using the atomic "cmpxchg" instruction. This | ||
8 | * code is an adaptation of the x86 version of "atomic_dec_and_lock()". | ||
9 | */ | ||
10 | |||
11 | #include <linux/compiler.h> | ||
12 | #include <linux/module.h> | ||
13 | #include <linux/spinlock.h> | ||
14 | #include <asm/atomic.h> | ||
15 | |||
16 | /* | ||
17 | * Decrement REFCOUNT and if the count reaches zero, acquire the spinlock. Both of these | ||
18 | * operations have to be done atomically, so that the count doesn't drop to zero without | ||
19 | * acquiring the spinlock first. | ||
20 | */ | ||
21 | int | ||
22 | _atomic_dec_and_lock (atomic_t *refcount, spinlock_t *lock) | ||
23 | { | ||
24 | int old, new; | ||
25 | |||
26 | do { | ||
27 | old = atomic_read(refcount); | ||
28 | new = old - 1; | ||
29 | |||
30 | if (unlikely (old == 1)) { | ||
31 | /* oops, we may be decrementing to zero, do it the slow way... */ | ||
32 | spin_lock(lock); | ||
33 | if (atomic_dec_and_test(refcount)) | ||
34 | return 1; | ||
35 | spin_unlock(lock); | ||
36 | return 0; | ||
37 | } | ||
38 | } while (cmpxchg(&refcount->counter, old, new) != old); | ||
39 | return 0; | ||
40 | } | ||
41 | |||
42 | EXPORT_SYMBOL(_atomic_dec_and_lock); | ||