diff options
Diffstat (limited to 'arch/x86/lib/memcpy_64.S')
-rw-r--r-- | arch/x86/lib/memcpy_64.S | 23 |
1 files changed, 8 insertions, 15 deletions
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index ad5441ed1b57..f82e884928af 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -20,12 +20,11 @@ /* * memcpy_c() - fast string ops (REP MOVSQ) based variant. * - * Calls to this get patched into the kernel image via the + * This gets patched over the unrolled variant (below) via the * alternative instructions framework: */ - ALIGN -memcpy_c: - CFI_STARTPROC + .section .altinstr_replacement, "ax", @progbits +.Lmemcpy_c: movq %rdi, %rax movl %edx, %ecx @@ -35,8 +34,8 @@ memcpy_c: movl %edx, %ecx rep movsb ret - CFI_ENDPROC -ENDPROC(memcpy_c) +.Lmemcpy_e: + .previous ENTRY(__memcpy) ENTRY(memcpy) @@ -128,16 +127,10 @@ ENDPROC(__memcpy) * It is also a lot simpler. Use this when possible: */ - .section .altinstr_replacement, "ax" -1: .byte 0xeb /* jmp <disp8> */ - .byte (memcpy_c - memcpy) - (2f - 1b) /* offset */ -2: - .previous - .section .altinstructions, "a" .align 8 .quad memcpy - .quad 1b + .quad .Lmemcpy_c .byte X86_FEATURE_REP_GOOD /* @@ -145,6 +138,6 @@ ENDPROC(__memcpy) * so it is silly to overwrite itself with nops - reboot is the * only outcome... */ - .byte 2b - 1b - .byte 2b - 1b + .byte .Lmemcpy_e - .Lmemcpy_c + .byte .Lmemcpy_e - .Lmemcpy_c .previous |