Re: [PATCH] fs: nfs: return per memcg count for xattr shrinkers

[Frank van der Linden]

On Sun, Sep 27, 2020 at 04:42:20AM -0700, Yang Shi wrote:
> 
> The list_lru_count() returns the pre node count, but the new xattr
> shrinkers are memcg aware, so the shrinkers should return per memcg
> count by calling list_lru_shrink_count() instead.  Otherwise over-shrink
> might be experienced.  The problem was spotted by visual code
> inspection.
> 
> Cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> Cc: Anna Schumaker <anna.schumaker@xxxxxxxxxx>
> Cc: Frank van der Linden <fllinden@xxxxxxxxxx>
> Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
> ---
>  fs/nfs/nfs42xattr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/nfs/nfs42xattr.c b/fs/nfs/nfs42xattr.c
> index 86777996cfec..6e5f34916937 100644
> --- a/fs/nfs/nfs42xattr.c
> +++ b/fs/nfs/nfs42xattr.c
> @@ -882,7 +882,7 @@ nfs4_xattr_cache_count(struct shrinker *shrink, struct shrink_control *sc)
>  {
>         unsigned long count;
> 
> -       count = list_lru_count(&nfs4_xattr_cache_lru);
> +       count = list_lru_shrink_count(&nfs4_xattr_cache_lru, sc);
>         return vfs_pressure_ratio(count);
>  }
> 
> @@ -976,7 +976,7 @@ nfs4_xattr_entry_count(struct shrinker *shrink, struct shrink_control *sc)
>         lru = (shrink == &nfs4_xattr_large_entry_shrinker) ?
>             &nfs4_xattr_large_entry_lru : &nfs4_xattr_entry_lru;
> 
> -       count = list_lru_count(lru);
> +       count = list_lru_shrink_count(lru, sc);
>         return vfs_pressure_ratio(count);
>  }
> 
> --
> 2.26.2
> 

Yep, thanks.

Reviewed-by: Frank van der Linden <fllinden@xxxxxxxxxx>