Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750830AbWATLGO (ORCPT ); Fri, 20 Jan 2006 06:06:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750825AbWATLGO (ORCPT ); Fri, 20 Jan 2006 06:06:14 -0500 Received: from relay.2ka.mipt.ru ([194.85.82.65]:38070 "EHLO 2ka.mipt.ru") by vger.kernel.org with ESMTP id S1750824AbWATLGN (ORCPT ); Fri, 20 Jan 2006 06:06:13 -0500 Date: Fri, 20 Jan 2006 14:02:30 +0300 From: Evgeniy Polyakov To: kus Kusche Klaus Cc: John Ronciak , Adrian Bunk , Lee Revell , linux-kernel@vger.kernel.org, john.ronciak@intel.com, ganesh.venkatesan@intel.com, jesse.brandeburg@intel.com, netdev@vger.kernel.org, Steven Rostedt Subject: Re: My vote against eepro* removal Message-ID: <20060120110230.GA24815@2ka.mipt.ru> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-1.7.5 (2ka.mipt.ru [0.0.0.0]); Fri, 20 Jan 2006 14:02:31 +0300 (MSK) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1652 Lines: 40 On Fri, Jan 20, 2006 at 11:19:20AM +0100, kus Kusche Klaus (kus@keba.com) wrote: > From: Evgeniy Polyakov > > Each MDIO read can take upto 2 msecs (!) and at least 20 > > usecs in e100, > > and this runs in timer handler. > > Concider attaching (only compile tested) patch which moves > > e100 watchdog > > into workqueue. > > Hmmm, I don't think moving it around is worth the trouble > (nevertheless, I will test later if I find time). > > For a full preemption kernel, both timer code and workqueue code > are executed in a thread of their own. If I know that there is a > 500 us piece of code in either of them, I have to adjust the prio > of the corresponding thread (and all others) accordingly anyway. > > For a non-full preemption kernel, your patch moves the 500 us > piece of code from kernel to thread context, so it really > improves things. But is 500 us something to worry about in a > non-full preemption kernel? In the worst case it will be milliseconds, which is not very nice timeout for timer handler... P.S. above patch works without problems with my e100 card. > -- > Klaus Kusche (Software Development - Control Systems) > KEBA AG Gewerbepark Urfahr, A-4041 Linz, Austria (Europe) > Tel: +43 / 732 / 7090-3120 Fax: +43 / 732 / 7090-6301 > E-Mail: kus@keba.com WWW: www.keba.com -- Evgeniy Polyakov - 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/