From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH -V3 1/1] cgroup: Add inotify event on change tasks file
 (fork, exit, move pid from file)
Date: Tue, 15 May 2012 08:28:44 -0700
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To: Eric Paris <eparis-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Cc: Al Viro <viro-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>, Alexander Nikiforov <a.nikiforov-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, "Kirill A. Shutemov" <kirill-oKw7cIdHH8eLwutG50LtGA@public.gmane.org>, lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, KAMEZAWA Hiroyuki <kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org>, Dmitry Solodkiy <d.solodkiy-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, npiggin-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org

Hello,

On Tue, May 15, 2012 at 11:25:17AM -0400, Eric Paris wrote:
> On Tue, 2012-05-15 at 08:16 -0700, Tejun Heo wrote:
> > On Mon, May 07, 2012 at 01:38:48PM -0700, Tejun Heo wrote:
> > > On Fri, May 04, 2012 at 06:43:30PM +0100, Al Viro wrote:
> > > > 	Consider that preemptively NAKed.  Eric, would you mind explaining
> > > > WTF would fsnotify *do* with vfsmount(s) here, seeing that they might very
> > > > well be not mounted in anyone's namespace?  And as for generating an event
> > > > for each, they might appear and disappear at zero notice.
> > > 
> > > Eric, any ideas on how to proceed?
> > 
> > Ping?
> 
> Oh sorry, if Al's correct, and there is just absolutely no way to come
> up with any kind of mnt for the path we have no choice.  Do it the way
> you were.

The thing is that people have been requesting recursive notification
for cgroup events (especially cgroup becoming empty).  IIRC, that
can't be done without path, right?  Why so?  Can we change that?

Thanks.

-- 
tejun