lkml.org 
[lkml]   [2017]   [Jun]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] swap: cond_resched in swap_cgroup_prepare()
[CC Andrew]

On Sun 04-06-17 13:01:09, Yu Zhao wrote:
> Saw need_resched() warnings when swapping on large swapfile (TBs)
> because continuously allocating many pages in swap_cgroup_prepare()
> took too long.
>
> We already cond_resched when freeing page in swap_cgroup_swapoff().
> Do the same for the page allocation.
>
> Signed-off-by: Yu Zhao <yuzhao@google.com>
> Acked-by: Michal Hocko <mhocko@suse.com>
> Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
> ---
> Changelog since v1:
> * clarify the problem in the commit message
>
> mm/swap_cgroup.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/mm/swap_cgroup.c b/mm/swap_cgroup.c
> index ac6318a064d3..3405b4ee1757 100644
> --- a/mm/swap_cgroup.c
> +++ b/mm/swap_cgroup.c
> @@ -48,6 +48,9 @@ static int swap_cgroup_prepare(int type)
> if (!page)
> goto not_enough_page;
> ctrl->map[idx] = page;
> +
> + if (!(idx % SWAP_CLUSTER_MAX))
> + cond_resched();
> }
> return 0;
> not_enough_page:
> --
> 2.13.0.506.g27d5fe0cd-goog

--
Michal Hocko
SUSE Labs

\
 
 \ /
  Last update: 2017-06-05 07:12    [W:0.305 / U:0.636 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site