Re: [PATCH 01/18] kernel: add bl_list

Andi Kleen
2010-10-08T08:18:47Z

Dave Chinner <david@fromorbit.com> writes:

> +static inline void __hlist_bl_del(struct hlist_bl_node *n)
> +{
> + struct hlist_bl_node *next = n->next;
> + struct hlist_bl_node **pprev = n->pprev;
> +
> + LIST_BL_BUG_ON((unsigned long)n & LIST_BL_LOCKMASK);
> +
> + /* pprev may be `first`, so be careful not to lose the lock bit */
> + *pprev = (struct hlist_bl_node *)
> + ((unsigned long)next |
> + ((unsigned long)*pprev & LIST_BL_LOCKMASK));
> + if (next)
> + next->pprev = pprev;
> +}

Should this set n->pprev to NULL so that unhashed returns true
afterwards?

> +
> +static inline void hlist_bl_del(struct hlist_bl_node *n)
> +{
> + __hlist_bl_del(n);
> + n->next = BL_LIST_POISON1;
> + n->pprev = BL_LIST_POISON2;
> +}

Ok so unhashed only works once. Seems unsymmetric.

Other than that looks good to me.

Reviewed-by: Andi Kleen <ak@linux.intel.com>

-Andi

--
ak@linux.intel.com -- Speaking for myself only.