On Wed 10-03-21 13:19:47, Feng Tang wrote:
[...]
> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> index d66c1c0..00b19f7 100644
> --- a/mm/mempolicy.c
> +++ b/mm/mempolicy.c
> @@ -2205,9 +2205,13 @@ static struct page *alloc_pages_policy(struct mempolicy *pol, gfp_t gfp,
> * | MPOL_PREFERRED_MANY (round 2) | local | NULL |
> * +-------------------------------+---------------+------------+
> */
> - if (pol->mode == MPOL_PREFERRED_MANY)
> + if (pol->mode == MPOL_PREFERRED_MANY) {
> gfp_mask |= __GFP_RETRY_MAYFAIL | __GFP_NOWARN;
>
> + /* Skip direct reclaim, as there will be a second try */
> + gfp_mask &= ~__GFP_DIRECT_RECLAIM;
__GFP_RETRY_MAYFAIL is a reclaim modifier which doesn't make any sense
without __GFP_DIRECT_RECLAIM. Also I think it would be better to have a
proper allocation flags in the initial patch which implements the
fallback.
> + }
> +
> page = __alloc_pages_nodemask(gfp_mask, order,
> policy_node(gfp, pol, preferred_nid),
> policy_nodemask(gfp, pol));
> --
> 2.7.4
>
>
--
Michal Hocko
SUSE Labs
