From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758815Ab3CEUDu (ORCPT ); Tue, 5 Mar 2013 15:03:50 -0500 Received: from terminus.zytor.com ([198.137.202.10]:36144 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758371Ab3CEUDr (ORCPT ); Tue, 5 Mar 2013 15:03:47 -0500 Message-ID: <51364F76.4060107@zytor.com> Date: Tue, 05 Mar 2013 12:03:02 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130219 Thunderbird/17.0.3 MIME-Version: 1.0 To: David Miller CC: bhutchings@solarflare.com, eliezer.tamir@linux.jf.intel.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, jesse.brandeburg@intel.com, e1000-devel@lists.sourceforge.net, willemb@google.com, andi@firstfloor.org, eliezer@tamir.org.il Subject: Re: [RFC PATCH 1/5] net: implement support for low latency socket polling References: <20130227175549.10611.82188.stgit@gitlad.jf.intel.com> <20130227175555.10611.42794.stgit@gitlad.jf.intel.com> <1362501781.2791.19.camel@bwh-desktop.uk.solarflarecom.com> <20130305.145524.1486936679665458305.davem@davemloft.net> In-Reply-To: <20130305.145524.1486936679665458305.davem@davemloft.net> X-Enigmail-Version: 1.5.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/05/2013 11:55 AM, David Miller wrote: > From: Ben Hutchings > Date: Tue, 5 Mar 2013 16:43:01 +0000 > >> In general it appears to require a run-time check. You might need to >> augment . > > On the other hand, unlike get_cycles, sched_clock() is always available. > On the gripping hand, we need to know when it uses something like jiffies, in which case we probably need to disable the whole interface. -hpa