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-rw-r--r--arch/ppc64/lib/dec_and_lock.c47
1 files changed, 0 insertions, 47 deletions
diff --git a/arch/ppc64/lib/dec_and_lock.c b/arch/ppc64/lib/dec_and_lock.c
deleted file mode 100644
index 7b9d4da5cf92..000000000000
--- a/arch/ppc64/lib/dec_and_lock.c
+++ /dev/null
@@ -1,47 +0,0 @@
1/*
2 * ppc64 version of atomic_dec_and_lock() using cmpxchg
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 */
9
10#include <linux/module.h>
11#include <linux/spinlock.h>
12#include <asm/atomic.h>
13#include <asm/system.h>
14
15/*
16 * This is an implementation of the notion of "decrement a
17 * reference count, and return locked if it decremented to zero".
18 *
19 * This implementation can be used on any architecture that
20 * has a cmpxchg, and where atomic->value is an int holding
21 * the value of the atomic (i.e. the high bits aren't used
22 * for a lock or anything like that).
23 */
24int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock)
25{
26 int counter;
27 int newcount;
28
29 for (;;) {
30 counter = atomic_read(atomic);
31 newcount = counter - 1;
32 if (!newcount)
33 break; /* do it the slow way */
34
35 newcount = cmpxchg(&atomic->counter, counter, newcount);
36 if (newcount == counter)
37 return 0;
38 }
39
40 spin_lock(lock);
41 if (atomic_dec_and_test(atomic))
42 return 1;
43 spin_unlock(lock);
44 return 0;
45}
46
47EXPORT_SYMBOL(_atomic_dec_and_lock);