From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753150AbeDJM0S (ORCPT ); Tue, 10 Apr 2018 08:26:18 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:52126 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753131AbeDJM0R (ORCPT ); Tue, 10 Apr 2018 08:26:17 -0400 Date: Tue, 10 Apr 2018 14:26:04 +0200 From: Peter Zijlstra To: Thomas Gleixner Cc: yuankuiz@codeaurora.org, "Rafael J. Wysocki" , Linux PM , "Rafael J. Wysocki" , Frederic Weisbecker , Ingo Molnar , Len Brown , Linux Kernel Mailing List , linux-pm-owner@vger.kernel.org Subject: Re: [PATCH] time: tick-sched: use bool for tick_stopped Message-ID: <20180410122604.GE4082@hirez.programming.kicks-ass.net> References: <891d4f632fbff5052e11f2d0b6fac35d@codeaurora.org> <20180410112637.GD4082@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 10, 2018 at 02:07:32PM +0200, Thomas Gleixner wrote: > On Tue, 10 Apr 2018, Peter Zijlstra wrote: > > Do you have any actual evidence for that? Is there a compiler stupid > > enough to generate code to convert a bool to a 1bit value? > > Sure, if you do: > > > > > > > > + bool tick_stopped : 1; > > which is stupidly allowed by the standard.... The code-gen changes are because of the layout change, not because of the type change.