[PATCH] x86_64: x86_64 version of the smp alternative patch.
Changes are largely identical to the i386 version:
* alternative #define are moved to the new alternative.h file.
* one new elf section with pointers to the lock prefixes which can be
nop'ed out for non-smp.
* two new elf sections simliar to the "classic" alternatives to
replace SMP code with simpler UP code.
* fixup headers to use alternative.h instead of defining their own
LOCK / LOCK_PREFIX macros.
The patch reuses the i386 version of the alternatives code to avoid code
duplication. The code in alternatives.c was shuffled around a bit to
reduce the number of #ifdefs needed. It also got some tweaks needed for
x86_64 (vsyscall page handling) and new features (noreplacement option
which was x86_64 only up to now). Debug printk's are changed from
compile-time to runtime.
Loosely based on a early version from Bastian Blank <waldi@debian.org>
Signed-off-by: Gerd Hoffmann <kraxel@suse.de>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-x86_64/semaphore.h b/include/asm-x86_64/semaphore.h
index a389aa6..064df08 100644
--- a/include/asm-x86_64/semaphore.h
+++ b/include/asm-x86_64/semaphore.h
@@ -106,7 +106,7 @@
__asm__ __volatile__(
"# atomic down operation\n\t"
- LOCK "decl %0\n\t" /* --sem->count */
+ LOCK_PREFIX "decl %0\n\t" /* --sem->count */
"js 2f\n"
"1:\n"
LOCK_SECTION_START("")
@@ -130,7 +130,7 @@
__asm__ __volatile__(
"# atomic interruptible down operation\n\t"
- LOCK "decl %1\n\t" /* --sem->count */
+ LOCK_PREFIX "decl %1\n\t" /* --sem->count */
"js 2f\n\t"
"xorl %0,%0\n"
"1:\n"
@@ -154,7 +154,7 @@
__asm__ __volatile__(
"# atomic interruptible down operation\n\t"
- LOCK "decl %1\n\t" /* --sem->count */
+ LOCK_PREFIX "decl %1\n\t" /* --sem->count */
"js 2f\n\t"
"xorl %0,%0\n"
"1:\n"
@@ -178,7 +178,7 @@
{
__asm__ __volatile__(
"# atomic up operation\n\t"
- LOCK "incl %0\n\t" /* ++sem->count */
+ LOCK_PREFIX "incl %0\n\t" /* ++sem->count */
"jle 2f\n"
"1:\n"
LOCK_SECTION_START("")