Re: [PATCH] mm/slab_common: provide "slab_merge" option for !IS_ENABLED(CONFIG_SLAB_MERGE_DEFAULT) builds

[Rafael Aquini]

On Fri, Mar 19, 2021 at 03:22:33PM -0400, Rafael Aquini wrote:
> This is a minor addition to the allocator setup options to provide
> a simple way to on demand enable back cache merging for builds
> that by default run with CONFIG_SLAB_MERGE_DEFAULT not set.
> 
> Signed-off-by: Rafael Aquini <aquini@xxxxxxxxxx>
> ---
>  Documentation/admin-guide/kernel-parameters.txt | 7 +++++++
>  mm/slab_common.c                                | 8 ++++++++
>  2 files changed, 15 insertions(+)
> 
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 04545725f187..06519eecbfec 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -4877,6 +4877,10 @@
>  
>  	slram=		[HW,MTD]
>  
> +	slab_merge	[MM]
> +			Enable merging of slabs with similar size when the
> +			kernel is built without CONFIG_SLAB_MERGE_DEFAULT.
> +
>  	slab_nomerge	[MM]
>  			Disable merging of slabs with similar size. May be
>  			necessary if there is some reason to distinguish
> @@ -4924,6 +4928,9 @@
>  			lower than slub_max_order.
>  			For more information see Documentation/vm/slub.rst.
>  
> +	slub_merge	[MM, SLUB]
> +			Same with slab_merge.
> +
>  	slub_nomerge	[MM, SLUB]
>  			Same with slab_nomerge. This is supported for legacy.
>  			See slab_nomerge for more information.
> diff --git a/mm/slab_common.c b/mm/slab_common.c
> index 88e833986332..30db72269036 100644
> --- a/mm/slab_common.c
> +++ b/mm/slab_common.c
> @@ -71,11 +71,19 @@ static int __init setup_slab_nomerge(char *str)
>  	return 1;
>  }
>  
> +static int __init setup_slab_merge(char *str)
> +{
> +	slab_nomerge = false;
> +	return 1;
> +}
> +
>  #ifdef CONFIG_SLUB
>  __setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0);
> +__setup_param("slub_merge", slub_merge, setup_slab_merge, 0);
>  #endif
>  
>  __setup("slab_nomerge", setup_slab_nomerge);
> +__setup("slab_merge", setup_slab_nomerge);
DOH! I missed the typo here         ^^   

Sorry.