Re: [PATCH mmotm] cgroup: remove rcu_read_lock() fromcss_get_next()

[KAMEZAWA Hiroyuki]

On Wed, 4 Mar 2009 09:59:20 +0530
Bharata B Rao <bharata@xxxxxxxxxxxxxxxxxx> wrote:

> cgroup: remove rcu_read_lock() from css_get_next()
> 
> Callers of css_get_next() are already calling css_get_next()
> under rcu_read_lock() and hence there there is no need for
> css_get_next() to re-acquire rcu_read_lock(). As per the
> comments in css_get_next(), let the callers accquire the
> rcu_read_lock().
> 
> Signed-off-by: Bharata B Rao <bharata@xxxxxxxxxxxxxxxxxx>

Yes, thank you for pointing out. This should be done by caller.

Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>


> ---
>  kernel/cgroup.c |    3 ---
>  1 file changed, 3 deletions(-)
> 
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -3553,7 +3553,6 @@ css_get_next(struct cgroup_subsys *ss, i
>  		return NULL;
>  
>  	BUG_ON(!ss->use_id);
> -	rcu_read_lock();
>  	/* fill start point for scan */
>  	tmpid = id;
>  	while (1) {
> @@ -3577,8 +3576,6 @@ css_get_next(struct cgroup_subsys *ss, i
>  		/* continue to scan from next id */
>  		tmpid = tmpid + 1;
>  	}
> -
> -	rcu_read_unlock();
>  	return ret;
>  }
>  
> Regards,
> Bharata.
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/