[LIB]: Consolidate _atomic_dec_and_lock()
Several implementations were essentialy a common piece of C code using
the cmpxchg() macro. Put the implementation in one spot that everyone
can share, and convert sparc64 over to using this.
Alpha is the lone arch-specific implementation, which codes up a
special fast path for the common case in order to avoid GP reloading
which a pure C version would require.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/ppc/lib/Makefile b/arch/ppc/lib/Makefile
index f1e1fb4..50358e4 100644
--- a/arch/ppc/lib/Makefile
+++ b/arch/ppc/lib/Makefile
@@ -2,7 +2,7 @@
# Makefile for ppc-specific library files..
#
-obj-y := checksum.o string.o strcase.o dec_and_lock.o div64.o
+obj-y := checksum.o string.o strcase.o div64.o
obj-$(CONFIG_8xx) += rheap.o
obj-$(CONFIG_CPM2) += rheap.o
diff --git a/arch/ppc/lib/dec_and_lock.c b/arch/ppc/lib/dec_and_lock.c
deleted file mode 100644
index b18f0d9..0000000
--- a/arch/ppc/lib/dec_and_lock.c
+++ /dev/null
@@ -1,38 +0,0 @@
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <asm/atomic.h>
-#include <asm/system.h>
-
-/*
- * This is an implementation of the notion of "decrement a
- * reference count, and return locked if it decremented to zero".
- *
- * This implementation can be used on any architecture that
- * has a cmpxchg, and where atomic->value is an int holding
- * the value of the atomic (i.e. the high bits aren't used
- * for a lock or anything like that).
- */
-int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock)
-{
- int counter;
- int newcount;
-
- for (;;) {
- counter = atomic_read(atomic);
- newcount = counter - 1;
- if (!newcount)
- break; /* do it the slow way */
-
- newcount = cmpxchg(&atomic->counter, counter, newcount);
- if (newcount == counter)
- return 0;
- }
-
- spin_lock(lock);
- if (atomic_dec_and_test(atomic))
- return 1;
- spin_unlock(lock);
- return 0;
-}
-
-EXPORT_SYMBOL(_atomic_dec_and_lock);