[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>

1 files changed, 4 insertions, 4 deletions

diff --git a/include/asm-x86_64/semaphore.h b/include/asm-x86_64/semaphore.h
index a389aa6fe80f..064df08b9a0f 100644
--- a/include/asm-x86_64/semaphore.h
+++ b/include/asm-x86_64/semaphore.h
@@ -106,7 +106,7 @@ static inline void down(struct semaphore * sem)
 
         __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 @@ static inline int down_interruptible(struct semaphore * sem)
 
         __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 @@ static inline int down_trylock(struct semaphore * sem)
 
         __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 @@ static inline void up(struct semaphore * sem)
 {
         __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("")