Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932090AbVIZVDt (ORCPT ); Mon, 26 Sep 2005 17:03:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932091AbVIZVDs (ORCPT ); Mon, 26 Sep 2005 17:03:48 -0400 Received: from mx1.redhat.com ([66.187.233.31]:33246 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S932090AbVIZVDq (ORCPT ); Mon, 26 Sep 2005 17:03:46 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: george@mvista.com X-Fcc: ~/Mail/linus Cc: tglx@linutronix.de, Ingo Molnar , Oleg Nesterov , linux-kernel@vger.kernel.org, Steven Rostedt , "Paul E. McKenney" , "'high-res-timers-discourse@lists.sourceforge.net'" Subject: Re: [PATCH 2.6.13-rc6-rt9] PI aware dynamic priority adjustment In-Reply-To: George Anzinger's message of Friday, 19 August 2005 18:36:30 -0700 <4306891E.9060409@mvista.com> X-Zippy-Says: I'll take ROAST BEEF if you're out of LAMB!! Message-Id: <20050926210334.65BC7180E1F@magilla.sf.frob.com> Date: Mon, 26 Sep 2005 14:03:34 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 936 Lines: 16 > On another issue along this line, I have been thinking of changing the > x86 TSC arch cycle size to 1ns. (NOT the resolution, the units for the > arch cycle.) The reason to do this is to correctly track changes in cpu > frequency as it is today, we would need to track down and update all > pending HR timers when ever the frequency changed. By using a common > unit all we need to do is change the conversion constants (well I guess > they would not be constants any more :). I REALLY don't want to do this > as it does add conversion overhead, but I can not think of another clean > way to track TSC frequency changes. sched_clock does this conversion at sampling time, too. - 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/