Re: [RFC 07/15] slub: Add defrag_used_ratio field and sysfs support

[Tycho Andersen]

On Fri, Mar 08, 2019 at 03:14:18PM +1100, Tobin C. Harding wrote:
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -3642,6 +3642,7 @@ static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags)
>  
>  	set_cpu_partial(s);
>  
> +	s->defrag_used_ratio = 30;
>  #ifdef CONFIG_NUMA
>  	s->remote_node_defrag_ratio = 1000;
>  #endif
> @@ -5261,6 +5262,28 @@ static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf)
>  }
>  SLAB_ATTR_RO(destroy_by_rcu);
>  
> +static ssize_t defrag_used_ratio_show(struct kmem_cache *s, char *buf)
> +{
> +	return sprintf(buf, "%d\n", s->defrag_used_ratio);
> +}
> +
> +static ssize_t defrag_used_ratio_store(struct kmem_cache *s,
> +				       const char *buf, size_t length)
> +{
> +	unsigned long ratio;
> +	int err;
> +
> +	err = kstrtoul(buf, 10, &ratio);
> +	if (err)
> +		return err;
> +
> +	if (ratio <= 100)
> +		s->defrag_used_ratio = ratio;
    else
        return -EINVAL;

maybe?

Tycho