Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760263AbYHFTWO (ORCPT ); Wed, 6 Aug 2008 15:22:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756686AbYHFTUS (ORCPT ); Wed, 6 Aug 2008 15:20:18 -0400 Received: from proxima.lp0.eu ([85.158.45.36]:55249 "EHLO proxima.lp0.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755681AbYHFTUR (ORCPT ); Wed, 6 Aug 2008 15:20:17 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=exim; d=fire.lp0.eu; h=Received:Message-ID:Date:From:User-Agent:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=G2PxcnZmp3XAmuGb8qPgKLoO9Vq7Q3/+Os3aSaRqds36EEiQgFcfm6pZ+uVhWK6pkBSGOr6W/LwG4BzbsmXH98rrOqMrUv+3TyrnfoZ6CExY0/eej/xFoPR9OFRRcXpU; Message-ID: <4899F96D.9060809@simon.arlott.org.uk> Date: Wed, 06 Aug 2008 20:20:13 +0100 From: Simon Arlott User-Agent: Thunderbird 2.0.0.16 (X11/20080726) MIME-Version: 1.0 To: Alan Stern CC: Rene Herman , Arjan van de Ven , linux-kernel@vger.kernel.org, mingo@elte.hu, Daniel Walker , USB list , Greg Kroah-Hartman Subject: Re: [PATCH RFC] USB: Add HCD fastboot References: In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1624 Lines: 37 On 06/08/08 20:11, Alan Stern wrote: > On Wed, 6 Aug 2008, Simon Arlott wrote: > >> On 31/07/08 20:16, Alan Stern wrote: >> >> > It's not entirely clear why usblp is blocking at all. Probably because >> >> > it is waiting on the device semaphores for devices that are currently >> >> > being probed -- the driver core won't allow two threads to probe the >> >> > same device concurrently. >> >> >> >> Ok - so there could be some big improvements to be had by making the hcd >> >> init happen as early as possible and the device initcalls later? >> > >> > Maybe. Perhaps a better approach would be to make the device driver >> > initcalls before there are any devices for their probe routines to >> > block on. >> >> What about this? >> >> The Makefiles become a bit messy, but by moving things around I get the >> desired effect without splitting their initcalls. > > Wouldn't it be much simpler, and less objectionable, to do what I > suggested earlier? That is, add a 5-second delay at the start of > hub_thread() in drivers/usb/core/hub.c. No messing with Makefiles, no > changes to the initcall scheduling. Aside from 5 seconds being too long, and anything less being a race between hub_thread() and driver initcalls, it doesn't improve anything because it'll still have to wait for the devices to finish initialising in userspace instead. -- Simon Arlott -- 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/