x86, alternative: Add altinstruction_entry macro

Add altinstruction_entry macro to generate .altinstructions section
entries from assembly code.  This should be less failure-prone than
open-coding.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-5-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h
index a63a68be1cce..94d420b360d1 100644
--- a/arch/x86/include/asm/alternative-asm.h
+++ b/arch/x86/include/asm/alternative-asm.h
@@ -15,4 +15,13 @@
         .endm
 #endif
 
+.macro altinstruction_entry orig alt feature orig_len alt_len
+        .align 8
+        .quad \orig
+        .quad \alt
+        .word \feature
+        .byte \orig_len
+        .byte \alt_len
+.endm
+
 #endif  /*  __ASSEMBLY__  */