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Diffstat (limited to 'arch/x86_64/lib/dec_and_lock.c')
-rw-r--r--arch/x86_64/lib/dec_and_lock.c40
1 files changed, 0 insertions, 40 deletions
diff --git a/arch/x86_64/lib/dec_and_lock.c b/arch/x86_64/lib/dec_and_lock.c
deleted file mode 100644
index ab43394dc77..00000000000
--- a/arch/x86_64/lib/dec_and_lock.c
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * x86 version of "atomic_dec_and_lock()" using
- * the atomic "cmpxchg" instruction.
- *
- * (For CPU's lacking cmpxchg, we use the slow
- * generic version, and this one never even gets
- * compiled).
- */
-
-#include <linux/spinlock.h>
-#include <asm/atomic.h>
-
-int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock)
-{
- int counter;
- int newcount;
-
-repeat:
- counter = atomic_read(atomic);
- newcount = counter-1;
-
- if (!newcount)
- goto slow_path;
-
- asm volatile("lock; cmpxchgl %1,%2"
- :"=a" (newcount)
- :"r" (newcount), "m" (atomic->counter), "0" (counter));
-
- /* If the above failed, "eax" will have changed */
- if (newcount != counter)
- goto repeat;
- return 0;
-
-slow_path:
- spin_lock(lock);
- if (atomic_dec_and_test(atomic))
- return 1;
- spin_unlock(lock);
- return 0;
-}