Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757575AbXEIQm1 (ORCPT ); Wed, 9 May 2007 12:42:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756017AbXEIQmU (ORCPT ); Wed, 9 May 2007 12:42:20 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:57957 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755799AbXEIQmT (ORCPT ); Wed, 9 May 2007 12:42:19 -0400 Date: Wed, 9 May 2007 09:42:07 -0700 From: Greg KH To: Cornelia Huck Cc: Linus Torvalds , Adrian Bunk , linux-kernel Subject: Re: Please revert 5adc55da4a7758021bcc374904b0f8b076508a11 (PCI_MULTITHREAD_PROBE) Message-ID: <20070509164207.GA28633@kroah.com> References: <20070508153713.344cc881@gondolin.boeblingen.de.ibm.com> <20070508141149.GJ4226@stusta.de> <20070508183846.28a94797@gondolin.boeblingen.de.ibm.com> <20070509095302.GA13053@kroah.com> <20070509153813.52a7c397@gondolin.boeblingen.de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070509153813.52a7c397@gondolin.boeblingen.de.ibm.com> User-Agent: Mutt/1.5.15 (2007-04-06) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1641 Lines: 40 On Wed, May 09, 2007 at 03:38:13PM +0200, Cornelia Huck wrote: > On Wed, 9 May 2007 02:53:02 -0700, > Greg KH wrote: > > > > 2. Sheer volume of devices on a bus. Even if the indivdual probing > > > doesn't take long, having all devices probed one after the other may > > > take a lot of time. Putting the actual probe on a thread makes it > > > possible to run several probes in parallel, thereby cutting probing > > > time. > > > > Again, not for PCI, right? > > It seems that everyone agrees now that moving PCI over to a new probing > model without individual driver support was a bad idea. So generic > multithreaded probing is dead. Why is it dead? Since when is PCI the only bus in the system? > > If you want to implement this for your bus type, fine, I have no > > objection to that at all, but not for PCI, it's just not worth it. > > Infrastructure for async probing might not be such a bad idea, though. > (Aren't there some huge PCI-based machines?) However, I don't really > care whether PCI or SCSI or $HUGE_BUS use it, but serial synchronous > probing on a bus looks like a killer on most large systems. PCI probing is just reading stuff from memory. The slowness happens when storage devices need to spin up and/or discover attached drives. So, the async stuff can be done in those buses if wanted/needed, PCI is not the problem here. thanks, greg k-h - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/