From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH 06/14] sysfs: Rewrite sysfs_get_dentry Date: Wed, 01 Aug 2007 19:02:05 +0900 Message-ID: <46B05A1D.5000703@gmail.com> References: <46AF15F6.6010202@suse.de> <46AF1E57.3030209@suse.de> <20070731141613.GC13674@htj.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Eric W. Biederman" Cc: Greg KH , Greg KH , cornelia.huck-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org, stern-nwvwT67g6+6dFdvTe/nMLpVzexx5G7lz@public.gmane.org, satyam-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, Linux Containers , Dave Hansen List-Id: containers.vger.kernel.org Hello, Eric. Eric W. Biederman wrote: > I will look a little more and see. But right now it looks like the > real problem with locking is that we use sysfs_mutex to lock the > sysfs_dirent s_children list. > > Instead it really looks like we should use i_mutex from the appropriate > inode. Or is there a real performance problem with forcing the directory > inodes in core when we modify the directories? I don't think there is any performance problem. Problems with using i_mutex were... * It was messy. I don't remember all the details now but IIRC symlink walk code was pretty complex. * And more importantly, inodes are reclaimable and might or might not be there. -- tejun