linux-kernel - [PATCH v4] arm64/cpufeature: Refactor conditional logic in init_cpu_ftr

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Message-ID: <20241115053740.20523-1-hardevsinh.palaniya@siliconsignals.io>
Date: Fri, 15 Nov 2024 11:06:35 +0530
From: Hardevsinh Palaniya <hardevsinh.palaniya@...iconsignals.io>
To: will@...nel.org,
	broonie@...nel.org,
	anshuman.khandual@....com
Cc: Hardevsinh Palaniya <hardevsinh.palaniya@...iconsignals.io>,
	Catalin Marinas <catalin.marinas@....com>,
	Marc Zyngier <maz@...nel.org>,
	Oliver Upton <oliver.upton@...ux.dev>,
	Ard Biesheuvel <ardb@...nel.org>,
	Mark Rutland <mark.rutland@....com>,
	Joey Gouly <joey.gouly@....com>,
	Ryan Roberts <ryan.roberts@....com>,
	linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH v4] arm64/cpufeature: Refactor conditional logic in init_cpu_ftr_reg()

Unnecessarily checks ftr_ovr == tmp in an extra else if, which is not
needed because that condition would already be true by default if the
previous conditions are not satisfied.

		if (ftr_ovr != tmp) {
		} else if (ftr_new != tmp) {
		} else if (ftr_ovr == tmp) {

Logic: The first and last conditions are inverses of each other, so
the last condition must be true if the first two conditions are false.

Additionally, all branches set the variable str, making the subsequent
"if (str)" check redundant

Reviewed-by: Mark Brown <broonie@...nel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@....com>
Signed-off-by: Hardevsinh Palaniya <hardevsinh.palaniya@...iconsignals.io>
---
Changelog in V2:

- remove str check

Change in V3:

- Add logic in commit msg
- Add review tag

Change in V4:

- Change subject line
- Add review tag
---
 arch/arm64/kernel/cpufeature.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 718728a85430..728709483fb7 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -989,17 +989,16 @@ static void init_cpu_ftr_reg(u32 sys_reg, u64 new)
 				/* Override was valid */
 				ftr_new = tmp;
 				str = "forced";
-			} else if (ftr_ovr == tmp) {
+			} else {
 				/* Override was the safe value */
 				str = "already set";
 			}
 
-			if (str)
-				pr_warn("%s[%d:%d]: %s to %llx\n",
-					reg->name,
-					ftrp->shift + ftrp->width - 1,
-					ftrp->shift, str,
-					tmp & (BIT(ftrp->width) - 1));
+			pr_warn("%s[%d:%d]: %s to %llx\n",
+				reg->name,
+				ftrp->shift + ftrp->width - 1,
+				ftrp->shift, str,
+				tmp & (BIT(ftrp->width) - 1));
 		} else if ((ftr_mask & reg->override->val) == ftr_mask) {
 			reg->override->val &= ~ftr_mask;
 			pr_warn("%s[%d:%d]: impossible override, ignored\n",
-- 
2.43.0