From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266310AbUG0HQw (ORCPT ); Tue, 27 Jul 2004 03:16:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266305AbUG0HQo (ORCPT ); Tue, 27 Jul 2004 03:16:44 -0400 Received: from fw.osdl.org ([65.172.181.6]:44685 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S266304AbUG0HOq (ORCPT ); Tue, 27 Jul 2004 03:14:46 -0400 Date: Tue, 27 Jul 2004 00:13:17 -0700 From: Andrew Morton To: Ravikiran G Thirumalai Cc: greg@kroah.com, linux-kernel@vger.kernel.org, viro@parcelfarce.linux.theplanet.co.uk, dipankar@in.ibm.com Subject: Re: [patch] Use kref for struct file.f_count refcounter Message-Id: <20040727001317.5c313b2d.akpm@osdl.org> In-Reply-To: <20040727065528.GB1270@obelix.in.ibm.com> References: <20040726150312.GJ1231@obelix.in.ibm.com> <20040726223036.281106c5.akpm@osdl.org> <20040727065528.GB1270@obelix.in.ibm.com> X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ravikiran G Thirumalai wrote: > > On Mon, Jul 26, 2004 at 10:30:36PM -0700, Andrew Morton wrote: > > Ravikiran G Thirumalai wrote: > > > > > > This patch makes use of the kref api for the > > > struct file.f_count refcounter. This depends > > > on the new kref apis kref_read and kref_put_last > > > added by means of my earlier patch today. > > > > Sorry, but I can't really see how this improves anything. It'll slow > > things down infinitesimally and it forces the reader to look elsewhere in > > the tree to see what's going on. > > > > It doesn't improve anything in terms of performance or anything. It just > makes use of the kref api for refcounting. My next patchset will be to > extend the kref api to do lockfree refcounting, and eliminate > use of files_struct.file_lock on the reader side (lock free fd lookup) . That would have been a useful thing to have mentioned in the description of these patches, no? > I can do a patch to just extend kref api for lockfree refcounting and > use them for for the lock free fd lookup patch directly if you like to see > it that way. uh, whatever you think is best will suit at this time. Please send all the patches, (as in: every single one) at the same time, with complete descriptions. Thanks.