linux-kernel - [PATCH v1 3/3] arm64/mm: Elide tlbi in contpte

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Message-ID: <20250219143837.44277-7-miko.lenczewski@arm.com>
Date: Wed, 19 Feb 2025 14:38:40 +0000
From: Mikołaj Lenczewski <miko.lenczewski@....com>
To: ryan.roberts@....com,
	yang@...amperecomputing.com,
	catalin.marinas@....com,
	will@...nel.org,
	joey.gouly@....com,
	broonie@...nel.org,
	mark.rutland@....com,
	james.morse@....com,
	yangyicong@...ilicon.com,
	robin.murphy@....com,
	anshuman.khandual@....com,
	maz@...nel.org,
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	david@...hat.com,
	baohua@...nel.org,
	ioworker0@...il.com,
	oliver.upton@...ux.dev,
	linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org
Cc: Mikołaj Lenczewski <miko.lenczewski@....com>
Subject: [PATCH v1 3/3] arm64/mm: Elide tlbi in contpte_convert() under BBML2

If we support bbml2 without conflict aborts, we can avoid the final
flush and have hardware manage the tlb entries for us. Avoiding flushes
is a win.

Signed-off-by: Mikołaj Lenczewski <miko.lenczewski@....com>
Reviewed-by: Ryan Roberts <ryan.roberts@....com>
---
 arch/arm64/mm/contpte.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c
index e26e8f8cfb9b..26a86248f897 100644
--- a/arch/arm64/mm/contpte.c
+++ b/arch/arm64/mm/contpte.c
@@ -72,9 +72,6 @@ static void contpte_convert(struct mm_struct *mm, unsigned long addr,
 		__flush_tlb_range(&vma, start_addr, addr, PAGE_SIZE, true, 3);
 
 	__set_ptes(mm, start_addr, start_ptep, pte, CONT_PTES);
-
-	if (system_supports_bbml2_noconflict())
-		__flush_tlb_range(&vma, start_addr, addr, PAGE_SIZE, true, 3);
 }
 
 void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
-- 
2.45.3