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| 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/ia64 | |
| parent | 4a805e863d6b9466baf7084e1d6fdbe6e0628d8e (diff) | |
| download | linux-4db2ce0199f04b6e99999f22e28ef9a0ae5f0d2f.tar.bz2 | |
[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/ia64')
| -rw-r--r-- | arch/ia64/Kconfig | 5 | ||||
| -rw-r--r-- | arch/ia64/lib/Makefile | 1 | ||||
| -rw-r--r-- | arch/ia64/lib/dec_and_lock.c | 42 |
3 files changed, 0 insertions, 48 deletions
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index ed25d66c8d50..945c15a0722b 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -298,11 +298,6 @@ config PREEMPT source "mm/Kconfig" -config HAVE_DEC_LOCK - bool - depends on (SMP || PREEMPT) - default y - config IA32_SUPPORT bool "Support for Linux/x86 binaries" help diff --git a/arch/ia64/lib/Makefile b/arch/ia64/lib/Makefile index 799407e7726f..cb1af597370b 100644 --- a/arch/ia64/lib/Makefile +++ b/arch/ia64/lib/Makefile @@ -15,7 +15,6 @@ lib-$(CONFIG_ITANIUM) += copy_page.o copy_user.o memcpy.o lib-$(CONFIG_MCKINLEY) += copy_page_mck.o memcpy_mck.o lib-$(CONFIG_PERFMON) += carta_random.o lib-$(CONFIG_MD_RAID5) += xor.o -lib-$(CONFIG_HAVE_DEC_LOCK) += dec_and_lock.o AFLAGS___divdi3.o = AFLAGS___udivdi3.o = -DUNSIGNED diff --git a/arch/ia64/lib/dec_and_lock.c b/arch/ia64/lib/dec_and_lock.c deleted file mode 100644 index c7ce92f968f1..000000000000 --- a/arch/ia64/lib/dec_and_lock.c +++ /dev/null @@ -1,42 +0,0 @@ -/* - * Copyright (C) 2003 Jerome Marchand, Bull S.A. - * Cleaned up by David Mosberger-Tang <davidm@hpl.hp.com> - * - * This file is released under the GPLv2, or at your option any later version. - * - * ia64 version of "atomic_dec_and_lock()" using the atomic "cmpxchg" instruction. This - * code is an adaptation of the x86 version of "atomic_dec_and_lock()". - */ - -#include <linux/compiler.h> -#include <linux/module.h> -#include <linux/spinlock.h> -#include <asm/atomic.h> - -/* - * Decrement REFCOUNT and if the count reaches zero, acquire the spinlock. Both of these - * operations have to be done atomically, so that the count doesn't drop to zero without - * acquiring the spinlock first. - */ -int -_atomic_dec_and_lock (atomic_t *refcount, spinlock_t *lock) -{ - int old, new; - - do { - old = atomic_read(refcount); - new = old - 1; - - if (unlikely (old == 1)) { - /* oops, we may be decrementing to zero, do it the slow way... */ - spin_lock(lock); - if (atomic_dec_and_test(refcount)) - return 1; - spin_unlock(lock); - return 0; - } - } while (cmpxchg(&refcount->counter, old, new) != old); - return 0; -} - -EXPORT_SYMBOL(_atomic_dec_and_lock); |