Commit 79b0379c authored by Brian Gerst's avatar Brian Gerst Committed by Ingo Molnar
Browse files

x86: Optimize loadsegment()



Zero the input register in the exception handler instead of
using an extra register to pass in a zero value.
Signed-off-by: default avatarBrian Gerst <brgerst@gmail.com>
LKML-Reference: <1259176706-5908-1-git-send-email-brgerst@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 3c93ca00
......@@ -156,18 +156,19 @@ extern void native_load_gs_index(unsigned);
* segment if something goes wrong..
*/
#define loadsegment(seg, value) \
do { \
unsigned short __val = value; \
asm volatile("\n" \
"1:\t" \
"movl %k0,%%" #seg "\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3:\t" \
"movl %k1, %%" #seg "\n\t" \
"jmp 2b\n" \
"2:\t" \
"xorl %k0,%k0\n\t" \
"jmp 1b\n" \
".previous\n" \
_ASM_EXTABLE(1b,3b) \
: :"r" (value), "r" (0) : "memory")
_ASM_EXTABLE(1b, 2b) \
: "+r" (__val) : : "memory"); \
} while (0)
/*
* Save a segment register away
......
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