linux-kernel - [PATCH 1/2] arm64/mm: Drop redundant 'level' range trimming in __tlbi

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Message-Id: <20251021052022.2898275-2-anshuman.khandual@arm.com>
Date: Tue, 21 Oct 2025 06:20:21 +0100
From: Anshuman Khandual <anshuman.khandual@....com>
To: linux-arm-kernel@...ts.infradead.org
Cc: Anshuman Khandual <anshuman.khandual@....com>,
	Catalin Marinas <catalin.marinas@....com>,
	Will Deacon <will@...nel.org>,
	linux-kernel@...r.kernel.org
Subject: [PATCH 1/2] arm64/mm: Drop redundant 'level' range trimming in __tlbi_level()

Page table level value has already known to be in the range [0..3] before
entering inside the conditional 'if' loop. Hence any subsequent trimming
is just redundant and can be dropped off.

Cc: Catalin Marinas <catalin.marinas@....com>
Cc: Will Deacon <will@...nel.org>
Cc: linux-arm-kernel@...ts.infradead.org
Cc: linux-kernel@...r.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@....com>
---
 arch/arm64/include/asm/tlbflush.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index 18a5dc0c9a54..131096094f5b 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -110,7 +110,7 @@ static inline unsigned long get_trans_granule(void)
 									\
 	if (alternative_has_cap_unlikely(ARM64_HAS_ARMv8_4_TTL) &&	\
 	    level >= 0 && level <= 3) {					\
-		u64 ttl = level & 3;					\
+		u64 ttl = level;					\
 		ttl |= get_trans_granule() << 2;			\
 		arg &= ~TLBI_TTL_MASK;					\
 		arg |= FIELD_PREP(TLBI_TTL_MASK, ttl);			\
-- 
2.30.2