Re: [PATCH 2/4] mm: introduce memalloc_noreclaim_{save,restore}

Hillf Danton
2017-04-07T07:38:43Z

On April 05, 2017 3:47 PM Vlastimil Babka wrote:
>
> The previous patch has shown that simply setting and clearing PF_MEMALLOC in
> current->flags can result in wrongly clearing a pre-existing PF_MEMALLOC flag
> and potentially lead to recursive reclaim. Let's introduce helpers that support
> proper nesting by saving the previous stat of the flag, similar to the existing
> memalloc_noio_* and memalloc_nofs_* helpers. Convert existing setting/clearing
> of PF_MEMALLOC within mm to the new helpers.
>
> There are no known issues with the converted code, but the change makes it more
> robust.
>
> Suggested-by: Michal Hocko <mhocko@suse.com>
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
> ---

Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>