From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751643AbbJOIOg (ORCPT ); Thu, 15 Oct 2015 04:14:36 -0400 Received: from www.linutronix.de ([62.245.132.108]:59010 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750732AbbJOIOe (ORCPT ); Thu, 15 Oct 2015 04:14:34 -0400 Date: Thu, 15 Oct 2015 10:13:36 +0200 (CEST) From: Thomas Gleixner To: Richard Cochran cc: Christopher Hall , jeffrey.t.kirsher@intel.com, hpa@zytor.com, mingo@redhat.com, john.stultz@linaro.org, peterz@infradead.org, x86@kernel.org, intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kevin.b.stanton@intel.com Subject: Re: [PATCH v4 1/4] Produce system time from correlated clocksource In-Reply-To: <20151015054142.GA4784@netboy> Message-ID: References: <1444675522-4198-1-git-send-email-christopher.s.hall@intel.com> <1444675522-4198-2-git-send-email-christopher.s.hall@intel.com> <20151013045832.GA2437@netboy> <20151013083113.GA1931@localhost.localdomain> <20151013211224.GA19242@netboy> <20151015054142.GA4784@netboy> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 15 Oct 2015, Richard Cochran wrote: > Thomas seems to say that there are *other* applications that will want > to transform device time into system time, but why does your audio > application use the system time, when the audio-to-ptp time is > directly available, without any man in the middle? PTP time is slow to access. Having a correlation to system time makes a log of things simpler; nanosleep is the most obvious example. Thanks, tglx