[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/rwlock.h b/include/asm-x86_64/rwlock.h
index 9942cc393064..dea0e9459264 100644
--- a/include/asm-x86_64/rwlock.h
+++ b/include/asm-x86_64/rwlock.h
@@ -24,7 +24,7 @@
 #define RW_LOCK_BIAS_STR        "0x01000000"
 
 #define __build_read_lock_ptr(rw, helper)   \
-        asm volatile(LOCK "subl $1,(%0)\n\t" \
+        asm volatile(LOCK_PREFIX "subl $1,(%0)\n\t" \
                      "js 2f\n" \
                      "1:\n" \
                     LOCK_SECTION_START("") \
@@ -34,7 +34,7 @@
                      ::"a" (rw) : "memory")
 
 #define __build_read_lock_const(rw, helper)   \
-        asm volatile(LOCK "subl $1,%0\n\t" \
+        asm volatile(LOCK_PREFIX "subl $1,%0\n\t" \
                      "js 2f\n" \
                      "1:\n" \
                     LOCK_SECTION_START("") \
@@ -54,7 +54,7 @@
                                         } while (0)
 
 #define __build_write_lock_ptr(rw, helper) \
-        asm volatile(LOCK "subl $" RW_LOCK_BIAS_STR ",(%0)\n\t" \
+        asm volatile(LOCK_PREFIX "subl $" RW_LOCK_BIAS_STR ",(%0)\n\t" \
                      "jnz 2f\n" \
                      "1:\n" \
                      LOCK_SECTION_START("") \
@@ -64,7 +64,7 @@
                      ::"a" (rw) : "memory")
 
 #define __build_write_lock_const(rw, helper) \
-        asm volatile(LOCK "subl $" RW_LOCK_BIAS_STR ",%0\n\t" \
+        asm volatile(LOCK_PREFIX "subl $" RW_LOCK_BIAS_STR ",%0\n\t" \
                      "jnz 2f\n" \
                      "1:\n" \
                     LOCK_SECTION_START("") \