From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [patch 1/4] fs: cleanup files_lock Date: Fri, 4 Jun 2010 04:38:18 -0400 Message-ID: <20100604083818.GA9987@infradead.org> References: <20100604064307.737085373@suse.de> <20100604072618.227745945@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Al Viro , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Frank Mayhar , John Stultz , Andi Kleen , Alan Cox , "Eric W. Biederman" , Greg Kroah-Hartman To: Nick Piggin Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:36124 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754391Ab0FDIiY (ORCPT ); Fri, 4 Jun 2010 04:38:24 -0400 Content-Disposition: inline In-Reply-To: <20100604072618.227745945@suse.de> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Fri, Jun 04, 2010 at 04:43:08PM +1000, Nick Piggin wrote: > Lock tty_files with a new spinlock, tty_files_lock; provide helpers to > manipulate the per-sb files list; unexport the files_lock spinlock. I'm still not entirely happy with this. You keep making the tty a special case by removing it from the files per-sb files list while nothing else in the system is removed from it. Thinks would be much better if you could untangle the tty code from abuse of file->f_u.fu_list entirely. And from a naive look at the tty code that actually seems pretty easy. file->private for ttys currently directly points to the tty struct. If you add a tty_private there which points back to the file, the tty and contains a list_head the open files in tty code tracking code can be completely divorced from the per-sb file tracking. After that we can decide what to do with the per-sb file tracking, where my favourite still is to get rid of it entirely.