diff options
author | David S. Miller <davem@davemloft.net> | 2005-09-14 21:47:01 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2005-09-14 21:47:01 -0700 |
commit | 4db2ce0199f04b6e99999f22e28ef9a0ae5f0d2f (patch) | |
tree | 87a00c97e02a77cdfec517398caa3f1d8f6a2f0d /arch/mips/lib | |
parent | 4a805e863d6b9466baf7084e1d6fdbe6e0628d8e (diff) | |
download | kernel-crypto-4db2ce0199f04b6e99999f22e28ef9a0ae5f0d2f.tar.gz kernel-crypto-4db2ce0199f04b6e99999f22e28ef9a0ae5f0d2f.tar.xz kernel-crypto-4db2ce0199f04b6e99999f22e28ef9a0ae5f0d2f.zip |
[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>
Diffstat (limited to 'arch/mips/lib')
-rw-r--r-- | arch/mips/lib/Makefile | 2 | ||||
-rw-r--r-- | arch/mips/lib/dec_and_lock.c | 47 |
2 files changed, 1 insertions, 48 deletions
diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile index 21b92b9dd01..03730341290 100644 --- a/arch/mips/lib/Makefile +++ b/arch/mips/lib/Makefile @@ -2,7 +2,7 @@ # Makefile for MIPS-specific library files.. # -lib-y += csum_partial_copy.o dec_and_lock.o memcpy.o promlib.o \ +lib-y += csum_partial_copy.o memcpy.o promlib.o \ strlen_user.o strncpy_user.o strnlen_user.o obj-y += iomap.o diff --git a/arch/mips/lib/dec_and_lock.c b/arch/mips/lib/dec_and_lock.c deleted file mode 100644 index fd82c84a93b..00000000000 --- a/arch/mips/lib/dec_and_lock.c +++ /dev/null @@ -1,47 +0,0 @@ -/* - * MIPS version of atomic_dec_and_lock() using cmpxchg - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ - -#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); |