Commit adf68192 authored by Uros Bizjak's avatar Uros Bizjak Committed by Ingo Molnar
Browse files

x86/bootflag: Micro-optimize sbf_write() 



Change parity bit with XOR when !parity instead of masking bit out
and conditionally setting it when !parity.

Saves a couple of bytes in the object file.

Co-developed-by: default avatar"H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: default avatar"H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: default avatarUros Bizjak <ubizjak@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250226153709.6370-1-ubizjak@gmail.com
parent 7d8f03f7

arch/x86/kernel/bootflag.c

+1 −2
Original line number Diff line number Diff line
@@ -38,9 +38,8 @@ static void __init sbf_write(u8 v) 
	unsigned long flags;



	if (sbf_port != -1) {

		v &= ~SBF_PARITY;

		if (!parity(v))

			v |= SBF_PARITY;

			v ^= SBF_PARITY;



		printk(KERN_INFO "Simple Boot Flag at 0x%x set to 0x%x\n",

			sbf_port, v);