From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [RFD] Merge task counter into memcg
Date: Tue, 17 Apr 2012 08:23:50 -0700
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To: Alexander Nikiforov <a.nikiforov-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Cc: "Daniel P. Berrange" <berrange-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Frederic Weisbecker <fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Containers <containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, Daniel Walsh <dwalsh-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Hugh Dickins <hughd-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
List-Id: containers.vger.kernel.org

Hello,

On Tue, Apr 17, 2012 at 10:45:05AM +0400, Alexander Nikiforov wrote:
> between them. Now we have only 1 way to get notification about tasks
> file - inotify(), but this approach works only if you work from
> userspace with file (e.g. create struct file, for example with echo
> $$ /sys/abc/tasks), but when something happens from kernel side
> (do_fork()/do_exit) we cannot get any event about group of the
> process (we can scan tasks file and count number of PID, or work
> with
> waitpid(), but IMHO this is ugly solutions)

Wouldn't simply generating FS_MODIFY event on the tasks file do the
trick?

Thanks.

-- 
tejun