linux-kernel - [PATCH v2 3/4] arm64/mm: Elide tlbi in contpte

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Message-ID: <20250228182403.6269-5-miko.lenczewski@arm.com>
Date: Fri, 28 Feb 2025 18:24:03 +0000
From: Mikołaj Lenczewski <miko.lenczewski@....com>
To: ryan.roberts@....com,
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Cc: Mikołaj Lenczewski <miko.lenczewski@....com>
Subject: [PATCH v2 3/4] 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 145530f706a9..77ed03b30b72 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_noabort())
-		__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