Re: [PATCH] Fix dcache race during umount

["Balbir Singh" <balbir@in.ibm.com>]

> Trying again after some useful comments from Balbir.
> Note: the change to prune_dcache looks quite different now.
>
> NeilBrown
>
<snip>
>                 tmp = dentry_unused.prev;
> +               if (unlikely(sb)) {
> +                       /* Try to find a dentry for this sb, but don't try
> +                        * too hard, if they aren't near the tail they will
> +                        * be moved down again soon
> +                        */
> +                       int skip = count;
> +                       while (skip &&
> +                              tmp != &dentry_unused &&
> +                              list_entry(tmp, struct dentry, d_lru)->d_sb != sb) {
> +                               skip--;
> +                               tmp = tmp->prev;
> +                       }
> +               }

This code looks very similar to the first pass in dcache_shrink_sb().
I would prefer if we could re-use that code here, but that would
require creating a helper function by splitting the function.

Looks like a good solution to me.

Regards,
Balbir