From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753579AbbBBRW4 (ORCPT ); Mon, 2 Feb 2015 12:22:56 -0500 Received: from mail-wg0-f52.google.com ([74.125.82.52]:64572 "EHLO mail-wg0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751753AbbBBRWz (ORCPT ); Mon, 2 Feb 2015 12:22:55 -0500 Date: Mon, 2 Feb 2015 18:22:47 +0100 From: Frederic Weisbecker To: Peter Zijlstra Cc: Ingo Molnar , LKML , Steven Rostedt , Linus Torvalds Subject: Re: [RFC PATCH 2/4] sched: Use traced preempt count operations to toggle PREEMPT_ACTIVE Message-ID: <20150202172244.GB11054@lerouge> References: <1422404652-29067-1-git-send-email-fweisbec@gmail.com> <1422404652-29067-3-git-send-email-fweisbec@gmail.com> <20150128154230.GH23038@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150128154230.GH23038@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 28, 2015 at 04:42:30PM +0100, Peter Zijlstra wrote: > On Wed, Jan 28, 2015 at 01:24:10AM +0100, Frederic Weisbecker wrote: > > d1f74e20b5b064a130cd0743a256c2d3cfe84010 turned PREEMPT_ACTIVE modifiers > > to use raw untraced preempt count operations. Meanwhile this prevents > > from debugging and tracing preemption disabled if we pull that > > responsibility to schedule() callers (see following patches). > > > Why do you care anyhow? The trace format has the preempt count in, so > any change is obvious. Yeah ok, lets keep things that way. Inc/dec PREEMPT_ACTIVE + PREEMPT_OFFSET from the same place doesn't change anything anyway wrt preempt tracing. It wasn't traced before so lets keep things that way and keep the raw preempt operations. If we want to trace this place, that's another problem.