diff mbox series

[RFC,v1,4/4] arm64/mm: Override ptep_get_lockless_norecency()

Message ID 20240215121756.2734131-5-ryan.roberts@arm.com (mailing list archive)
State New
Headers show
Series Reduce cost of ptep_get_lockless on arm64 | expand

Commit Message

Ryan Roberts Feb. 15, 2024, 12:17 p.m. UTC
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(+)

--
2.25.1

Comments

David Hildenbrand March 26, 2024, 4:35 p.m. UTC | #1
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>
diff mbox series

Patch

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)
 {
 	/*