[PATCH 03/17] x86: Replace open-coded parity calculation with parity8()
From: Kuan-Wei Chiu <visitorckw@gmail.com>
Date: 2025-02-23 16:43:23
Also in:
bpf, dri-devel, linux-input, linux-media, linux-serial, linux-wireless, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Refactor parity calculations to use the standard parity8() helper. This change eliminates redundant implementations and improves code efficiency. Co-developed-by: Yu-Chun Lin <redacted> Signed-off-by: Yu-Chun Lin <redacted> Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com> --- arch/x86/kernel/bootflag.c | 18 +++--------------- 1 file changed, 3 insertions(+), 15 deletions(-)
diff --git a/arch/x86/kernel/bootflag.c b/arch/x86/kernel/bootflag.c
index 3fed7ae58b60..314ff0e84900 100644
--- a/arch/x86/kernel/bootflag.c
+++ b/arch/x86/kernel/bootflag.c@@ -8,6 +8,7 @@ #include <linux/string.h> #include <linux/spinlock.h> #include <linux/acpi.h> +#include <linux/bitops.h> #include <asm/io.h> #include <linux/mc146818rtc.h>
@@ -20,26 +21,13 @@ int sbf_port __initdata = -1; /* set via acpi_boot_init() */ -static int __init parity(u8 v) -{ - int x = 0; - int i; - - for (i = 0; i < 8; i++) { - x ^= (v & 1); - v >>= 1; - } - - return x; -} - static void __init sbf_write(u8 v) { unsigned long flags; if (sbf_port != -1) { v &= ~SBF_PARITY; - if (!parity(v)) + if (!parity8(v)) v |= SBF_PARITY; printk(KERN_INFO "Simple Boot Flag at 0x%x set to 0x%x\n",
@@ -70,7 +58,7 @@ static int __init sbf_value_valid(u8 v) { if (v & SBF_RESERVED) /* Reserved bits */ return 0; - if (!parity(v)) + if (!parity8(v)) return 0; return 1;
--
2.34.1