Generic semaphore implementation

Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility.  Thanks to Peter Zijlstra for fixing the lockdep
warning.  Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Matthew Wilcox
2008-03-07 21:55:58 -05:00
committed by Matthew Wilcox
parent e48b3deee4
commit 64ac24e738
113 changed files with 314 additions and 7679 deletions

View File

@@ -5,4 +5,4 @@
EXTRA_AFLAGS := -traditional
lib-y := ashldi3.o ashrdi3.o lshrdi3.o muldi3.o \
checksum.o string.o semaphore.o uaccess.o
checksum.o string.o uaccess.o

View File

@@ -1,53 +0,0 @@
/*
* linux/arch/m68k/lib/semaphore.S
*
* Copyright (C) 1996 Linus Torvalds
*
* m68k version by Andreas Schwab
*/
#include <linux/linkage.h>
#include <asm/semaphore.h>
/*
* The semaphore operations have a special calling sequence that
* allow us to do a simpler in-line version of them. These routines
* need to convert that sequence back into the C sequence when
* there is contention on the semaphore.
*/
ENTRY(__down_failed)
moveml %a0/%d0/%d1,-(%sp)
movel %a1,-(%sp)
jbsr __down
movel (%sp)+,%a1
moveml (%sp)+,%a0/%d0/%d1
rts
ENTRY(__down_failed_interruptible)
movel %a0,-(%sp)
movel %d1,-(%sp)
movel %a1,-(%sp)
jbsr __down_interruptible
movel (%sp)+,%a1
movel (%sp)+,%d1
movel (%sp)+,%a0
rts
ENTRY(__down_failed_trylock)
movel %a0,-(%sp)
movel %d1,-(%sp)
movel %a1,-(%sp)
jbsr __down_trylock
movel (%sp)+,%a1
movel (%sp)+,%d1
movel (%sp)+,%a0
rts
ENTRY(__up_wakeup)
moveml %a0/%d0/%d1,-(%sp)
movel %a1,-(%sp)
jbsr __up
movel (%sp)+,%a1
moveml (%sp)+,%a0/%d0/%d1
rts