From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030439AbWFJQfb (ORCPT ); Sat, 10 Jun 2006 12:35:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932447AbWFJQfb (ORCPT ); Sat, 10 Jun 2006 12:35:31 -0400 Received: from a34-mta02.direcpc.com ([66.82.4.91]:11452 "EHLO a34-mta02.direcway.com") by vger.kernel.org with ESMTP id S932314AbWFJQfa (ORCPT ); Sat, 10 Jun 2006 12:35:30 -0400 Date: Sat, 10 Jun 2006 12:34:46 -0400 From: Ben Collins Subject: Re: [PATCH] kthread conversion: convert ieee1394 from kernel_thread In-reply-to: <20060610154213.GA19077@infradead.org> To: Christoph Hellwig Cc: Stefan Richter , "Serge E. Hallyn" , weihs@ict.tuwien.ac.at, linux1394-devel@lists.sourceforge.net, bcollins@debian.org, "Eric W. Biederman" , lkml Message-id: <1149957286.4448.542.camel@grayson> Organization: Ubuntu MIME-version: 1.0 X-Mailer: Evolution 2.6.1 Content-type: text/plain Content-transfer-encoding: 7BIT References: <20060610143100.GA15536@sergelap.austin.ibm.com> <20060610144205.GA13850@infradead.org> <448AE12E.5060002@s5r6.in-berlin.de> <20060610154213.GA19077@infradead.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2006-06-10 at 16:42 +0100, Christoph Hellwig wrote: > On Sat, Jun 10, 2006 at 05:11:42PM +0200, Stefan Richter wrote: > > Serge, could you reduce your patch to the nodemgr part and resubmit? > > I'd prefer ieee1394 would just stop creating these thread entirely. > Sure, rescaning the bus might take some time, but so do pci or especially > scsi bus rescans. A user should expect his thread to block when he > writes to an attribute caled rescan. 1394 bus rescanning takes a _lot_ longer than a PCI rescan. If we don't do this in a kthread, then we have to do it as a tasklet, and take a chance of stalling for a few seconds (not ms), preventing other tasklet's from running. Suboptimal, IMO. Also, neither PCI nor SCSI rescans occur quite as often as 1394 rescans. It's more like USB (which also uses a kthread, or at least used to). -- Ubuntu - http://www.ubuntu.com/ Debian - http://www.debian.org/ Linux 1394 - http://www.linux1394.org/ SwissDisk - http://www.swissdisk.com/