Re: [PATCH] memcg: deprecate memory.force_empty knob

[Michal Hocko]

On Mon 12-05-14 11:25:07, Tejun Heo wrote:
> On Mon, May 12, 2014 at 05:20:15PM +0200, Michal Hocko wrote:
> > On Mon 12-05-14 11:00:14, Tejun Heo wrote:
> > > On Mon, May 12, 2014 at 04:58:03PM +0200, Michal Hocko wrote:
> > > > @@ -4793,6 +4793,10 @@ static int mem_cgroup_force_empty_write(struct cgroup_subsys_state *css,
> > > >  
> > > >  	if (mem_cgroup_is_root(memcg))
> > > >  		return -EINVAL;
> > > > +	pr_info("%s (%d): memory.force_empty is deprecated and will be removed.",
> > > > +			current->comm, task_pid_nr(current));
> > > > +	pr_cont(" Let us know if you know if it needed in your usecase at");
> > > > +	pr_cont(" linux-mm@xxxxxxxxx\n");
> > > >  	return mem_cgroup_force_empty(memcg);
> > > 
> > > It probably would be way easier to just mark the knob with
> > > CFTYPE_INSANE.
> > 
> > That would prevent from creating the file, right? I do not mind that but
> > I would like to see people complaining before.
> 
> Oh sure, if you wanna see people complaining before the roll out of
> unified hierarchy, but let's make sure it's also marked with
> CFTYPE_INSANE.  It's easy to remove the flag afterwards.  The other
> way isn't, so...
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