Re: [PATCH 1/8] cgroup: kill cgroup_subsys->__DEPRECATED_clear_css_refs

[Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>]

On Wed 31-10-12 12:44:03, Tejun Heo wrote:
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index 7981850..8c605e2 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -865,11 +865,8 @@ static int cgroup_call_pre_destroy(struct cgroup *cgrp)
>  			continue;
>  
>  		ret = ss->pre_destroy(cgrp);
> -		if (ret) {
> -			/* ->pre_destroy() failure is being deprecated */
> -			WARN_ON_ONCE(!ss->__DEPRECATED_clear_css_refs);
> +		if (WARN_ON_ONCE(ret))
>  			break;
> -		}
>  	}
>  
>  	return ret;

And sorry for being to annoying about this WARN_ON_ONCE but I really
don't see any reason for it. pre_destroy can still happen and now it is
even reduced to a reasonable condition (somebody shown up). So I would
put it out of way as it doesn't give us anything and as I've already
mentioned one can trigger it really easily.

-- 
Michal Hocko
SUSE Labs