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Date: Tue, 26 Mar 2024 17:35:11 +0100
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Subject: Re: [RFC PATCH v1 4/4] arm64/mm: Override
 ptep_get_lockless_norecency()
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To: Ryan Roberts <ryan.roberts@arm.com>, Mark Rutland <mark.rutland@arm.com>,
 Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>,
 Alexander Shishkin <alexander.shishkin@linux.intel.com>,
 Jiri Olsa <jolsa@kernel.org>, Ian Rogers <irogers@google.com>,
 Adrian Hunter <adrian.hunter@intel.com>,
 Andrew Morton <akpm@linux-foundation.org>,
 Muchun Song <muchun.song@linux.dev>
Cc: linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org
References: <20240215121756.2734131-1-ryan.roberts@arm.com>
 <20240215121756.2734131-5-ryan.roberts@arm.com>
From: David Hildenbrand <david@redhat.com>
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In-Reply-To: <20240215121756.2734131-5-ryan.roberts@arm.com>
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On 15.02.24 13:17, Ryan Roberts wrote:
> Override ptep_get_lockless_norecency() when CONFIG_ARM64_CONTPTE is
> enabled. Because this API doesn't require the access and dirty bits to
> be accurate, for the contpte case, we can avoid reading all ptes in the
> contpte block to collect those bits, in contrast to ptep_get_lockless().
> 
> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
> ---
>   arch/arm64/include/asm/pgtable.h | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 401087e8a43d..c0e4ccf74714 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -1287,6 +1287,12 @@ static inline pte_t ptep_get_lockless(pte_t *ptep)
>   	return contpte_ptep_get_lockless(ptep);
>   }
> 
> +#define ptep_get_lockless_norecency ptep_get_lockless_norecency
> +static inline pte_t ptep_get_lockless_norecency(pte_t *ptep)
> +{
> +	return __ptep_get(ptep);
> +}
> +
>   static inline void set_pte(pte_t *ptep, pte_t pte)
>   {
>   	/*
> --
> 2.25.1
> 

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb