From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Subject: Re: [patch 1/2] fs: cleanup files_lock Date: Thu, 18 Mar 2010 01:38:26 +1100 Message-ID: <20100317143826.GM2869@laptop> References: <20100316094423.GM2869@laptop> <20100317141602.GA26661@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Al Viro , Frank Mayhar , John Stultz , Andi Kleen , linux-fsdevel@vger.kernel.org, Alan Cox , "Eric W. Biederman" , Linus Torvalds To: Greg KH Return-path: Received: from cantor.suse.de ([195.135.220.2]:46063 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753562Ab0CQOik (ORCPT ); Wed, 17 Mar 2010 10:38:40 -0400 Content-Disposition: inline In-Reply-To: <20100317141602.GA26661@suse.de> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Wed, Mar 17, 2010 at 07:16:02AM -0700, Greg KH wrote: > On Tue, Mar 16, 2010 at 08:44:23PM +1100, Nick Piggin wrote: > > I would like to start sending bits of vfs scalability improvements to > > be reviewed and hopefully merged. > > > > I will start with files_lock. Last time this one came up, it was > > criticised because some hoped to get rid of files list, and because > > it didn't have enough justification of the scalability improvement. > > > > For the first criticism, it isn't any more difficult to rip out if > > we are ever able to remove files list. For the second, I have gathered > > some statistics and written better justification. Andi I believe is > > finding kbuild is becoming limited by files lock on larger systems. > > > > -- > > > > fs: cleanup files_lock > > > > Lock tty_files with a new spinlock, tty_files_lock; provide helpers to > > manipulate the per-sb files list; unexport the files_lock spinlock. > > > > Signed-off-by: Nick Piggin > > Looks good to me. So long as the tty file always gets removed before file_sb_list_del in __fput or put_filp. Otherwise file_sb_list_del would use the wrong lock for it. As far as I could see, it should always get removed by tty_release. > Do you want me to apply this to my tty tree, or do > you want to take it through your tree because your other patch depends > on this? > > If you want to do it, feel free to add: > Acked-by: Greg Kroah-Hartman > to the patch. If they aren't both applied to -vfs tree in this round I'll ask you to apply this one. Thanks, Nick