From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751307Ab0JAEe3 (ORCPT ); Fri, 1 Oct 2010 00:34:29 -0400 Received: from relay3.sgi.com ([192.48.152.1]:57554 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750906Ab0JAEe2 (ORCPT ); Fri, 1 Oct 2010 00:34:28 -0400 Date: Thu, 30 Sep 2010 23:34:13 -0500 From: Robin Holt To: Eric Dumazet Cc: Robin Holt , David Miller , dipankar@in.ibm.com, viro@zeniv.linux.org.uk, bcrl@kvack.org, den@openvz.org, mingo@elte.hu, mszeredi@suse.cz, cmm@us.ibm.com, npiggin@kernel.dk, xemul@openvz.org, linux-kernel@vger.kernel.org, netdev Subject: Re: [PATCH V3] fs: allow for more than 2^31 files Message-ID: <20101001043413.GN14068@sgi.com> References: <20100923121704.GR14064@sgi.com> <1285246384.362.3.camel@edumazet-laptop> <20100923141037.GA3811@in.ibm.com> <20100927.153639.212415479.davem@davemloft.net> <1285645611.10438.27.camel@edumazet-laptop> <20100930202612.GM14068@sgi.com> <1285879545.2705.4.camel@edumazet-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1285879545.2705.4.camel@edumazet-laptop> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 30, 2010 at 10:45:45PM +0200, Eric Dumazet wrote: > Le jeudi 30 septembre 2010 à 15:26 -0500, Robin Holt a écrit : > > On Tue, Sep 28, 2010 at 05:46:51AM +0200, Eric Dumazet wrote: > > > Le lundi 27 septembre 2010 à 15:36 -0700, David Miller a écrit : > > ... > > > > > Fix is to let /proc/sys/fs/file-nr & /proc/sys/fs/file-max use long > > > integers, and change af_unix to use an atomic_long_t instead of > > > atomic_t. > > > > > > get_max_files() is changed to return an unsigned long. > > > > I _THINK_ we actually want get_max_files to return a long and have > > the files_stat_struct definitions be longs. If we do not have it that > > way, we could theoretically open enough files on a single cpu to make > > get_nr_files return a negative without overflowing max_files. That, > > of course, would require an insane amount of memory, but I think it is > > technically more correct. > > > > Number of opened file is technically a positive (or null) value, I have > no idea why you want it being signed. > > > > > > --- a/kernel/sysctl.c > > > +++ b/kernel/sysctl.c > > > @@ -1352,16 +1352,16 @@ static struct ctl_table fs_table[] = { > > > { > > > .procname = "file-nr", > > > .data = &files_stat, > > > - .maxlen = 3*sizeof(int), > > > + .maxlen = sizeof(files_stat), > > > .mode = 0444, > > > - .proc_handler = proc_nr_files, > > > + .proc_handler = proc_doulongvec_minmax, > > > > With this change, don't we lose the current nr_files value? I think > > you need proc_nr_files to stay as it was. If you disagree, we should > > probably eliminate the definitions for proc_nr_files as I don't believe > > they are used anywhere else. > > > > I have no idea why you think I changed something. I only made the value > use 64bit on 64bit arches, so that we are not anymore limited to 2^31 > files. The proc_handler used to be proc_nr_files() which would call get_nr_files() and deposit the result in files_stat.nr_files then cascade to proc_dointvec() which would dump the 3 values. Now it will dump the three values, but not update the middle (nr_files) value first. Robin