Re: [PATCH 2/2] mm/cgroup: delay soft limit data allocation
From: Balbir Singh
Date: Wed Feb 22 2017 - 20:24:41 EST
On Wed, Feb 22, 2017 at 04:58:11PM +0100, Laurent Dufour wrote:
> Until a soft limit is set to a cgroup, the soft limit data are useless
> so delay this allocation when a limit is set.
> Suggested-by: Michal Hocko <mhocko@xxxxxxxxxx>
> Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxxxxxxx>
> @@ -3000,6 +3035,8 @@ static ssize_t mem_cgroup_write(struct kernfs_open_file *of,
> case RES_SOFT_LIMIT:
> + if (!soft_limit_initialized)
> + soft_limit_initialize();
What happens if this fails? Do we disable this interface?
It's a good idea, but I wonder if we can deal with certain
memory cgroups not supporting soft limits due to memory
shortage at the time of using them.
> memcg->soft_limit = nr_pages;
> ret = 0;