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: Fri, 4 May 2012 10:04:12 -0700
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To: Alexander Nikiforov <a.nikiforov-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Cc: Eric Paris <eparis-H+wXaHxf7aLQT0dZR+AlfA@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>, viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org, npiggin-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org

On Fri, May 04, 2012 at 09:24:40AM +0400, Alexander Nikiforov wrote:
> Hi Eric,
> 
> I had try to implement with FSNOTIFY_EVENT_PATH. But it's pretty
> hard to obtain struct path without full chain of the sys_open()
> or may be I don't know some simple way. I'll spend some more time on
> this, but for now I have no idea how to do it. If you have some
> please share them.

Hmm... we have dentry from cfe->dentry and we can either use the first
vfsmount from sb->s_mounts or all of them (ie. generate event on each
vfsmount).  It's kinda silly either way tho.  Eric, it might be a good
idea to provide generic helper for virtual filesystems which want to
generate superblock-wide events?

Thanks.

-- 
tejun