maple_tree: slub sheaves conversion

[PATCH 03/12] maple_tree: use percpu sheaves for maple_node_cache

Posted by Vlastimil Babka 3 months, 1 week ago

Setup the maple_node_cache with percpu sheaves of size 32 to hopefully
improve its performance. Note this will not immediately take advantage
of sheaf batching of kfree_rcu() operations due to the maple tree using
call_rcu with custom callbacks. The followup changes to maple tree will
change that and also make use of the prefilled sheaves functionality.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
---
 lib/maple_tree.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index b4ee2d29d7a962ca374467d0533185f2db3d35ff..a0db6bdc63793b8bbd544e246391d99e880dede3 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -6302,9 +6302,14 @@ bool mas_nomem(struct ma_state *mas, gfp_t gfp)
 
 void __init maple_tree_init(void)
 {
+	struct kmem_cache_args args = {
+		.align  = sizeof(struct maple_node),
+		.sheaf_capacity = 32,
+	};
+
 	maple_node_cache = kmem_cache_create("maple_node",
-			sizeof(struct maple_node), sizeof(struct maple_node),
-			SLAB_PANIC, NULL);
+			sizeof(struct maple_node), &args,
+			SLAB_PANIC);
 }
 
 /**

-- 
2.51.0

Re: [PATCH 03/12] maple_tree: use percpu sheaves for maple_node_cache

Posted by Sidhartha Kumar 3 months, 1 week ago

On 9/1/25 7:08 AM, Vlastimil Babka wrote:
> Setup the maple_node_cache with percpu sheaves of size 32 to hopefully
> improve its performance. Note this will not immediately take advantage
> of sheaf batching of kfree_rcu() operations due to the maple tree using
> call_rcu with custom callbacks. The followup changes to maple tree will
> change that and also make use of the prefilled sheaves functionality.
> 
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
> Reviewed-by: Suren Baghdasaryan <surenb@google.com>

Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>

> ---
>   lib/maple_tree.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index b4ee2d29d7a962ca374467d0533185f2db3d35ff..a0db6bdc63793b8bbd544e246391d99e880dede3 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -6302,9 +6302,14 @@ bool mas_nomem(struct ma_state *mas, gfp_t gfp)
>   
>   void __init maple_tree_init(void)
>   {
> +	struct kmem_cache_args args = {
> +		.align  = sizeof(struct maple_node),
> +		.sheaf_capacity = 32,
> +	};
> +
>   	maple_node_cache = kmem_cache_create("maple_node",
> -			sizeof(struct maple_node), sizeof(struct maple_node),
> -			SLAB_PANIC, NULL);
> +			sizeof(struct maple_node), &args,
> +			SLAB_PANIC);
>   }
>   
>   /**
>