From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262154AbVGKQxx (ORCPT ); Mon, 11 Jul 2005 12:53:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262172AbVGKQvv (ORCPT ); Mon, 11 Jul 2005 12:51:51 -0400 Received: from gateway-1237.mvista.com ([12.44.186.158]:7407 "EHLO av.mvista.com") by vger.kernel.org with ESMTP id S262177AbVGKQtx (ORCPT ); Mon, 11 Jul 2005 12:49:53 -0400 Subject: Re: Attempted summary of "RT patch acceptance" thread, take 2 From: Daniel Walker To: paulmck@us.ibm.com Cc: linux-kernel@vger.kernel.org In-Reply-To: <20050711164322.GD1304@us.ibm.com> References: <20050711145552.GA1489@us.ibm.com> <1121098272.7050.13.camel@c-67-188-6-232.hsd1.ca.comcast.net> <20050711164322.GD1304@us.ibm.com> Content-Type: text/plain Date: Mon, 11 Jul 2005 09:49:48 -0700 Message-Id: <1121100589.7050.24.camel@c-67-188-6-232.hsd1.ca.comcast.net> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-4) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2005-07-11 at 09:43 -0700, Paul E. McKenney wrote: > Hello, Daniel, > > In principle, one could inspect the Linux kernel with the PREEMPT_RT patch > applied, and calculate the worst-case time during which interrupts are > disabled, though I have not heard of anyone actually doing this. Is this > what you are getting at, or are you thinking in terms of Kristian's and > Karim's testing? Well with the PREEMPT_RT patch applied the interrupt off sections are reduced to a small number, ~100 irrespective of config options or drivers (although I think APM might be the one exception) . So with the patch applied it becomes trivial to test/inspect each of the interrupt off sections , and thus give a hard guarantee for _all_ PREEMPT_RT kernels. Daniel