Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758183Ab3HMPhI (ORCPT ); Tue, 13 Aug 2013 11:37:08 -0400 Received: from mail-la0-f50.google.com ([209.85.215.50]:45238 "EHLO mail-la0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757619Ab3HMPhG (ORCPT ); Tue, 13 Aug 2013 11:37:06 -0400 Date: Tue, 13 Aug 2013 19:37:03 +0400 From: Cyrill Gorcunov To: "H. Peter Anvin" Cc: Andy Lutomirski , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, xemul@parallels.com, mpm@selenic.com, xiaoguangrong@linux.vnet.ibm.com, mtosatti@redhat.com, kosaki.motohiro@gmail.com, sfr@canb.auug.org.au, peterz@infradead.org, aneesh.kumar@linux.vnet.ibm.com, Ingo Molnar , Thomas Gleixner Subject: Re: [patch 2/2] [PATCH] mm: Save soft-dirty bits on file pages Message-ID: <20130813153703.GE2869@moon> References: <20130730204154.407090410@gmail.com> <20130730204654.966378702@gmail.com> <20130807132812.60ad4bfe85127794094d385e@linux-foundation.org> <20130808145120.GA1775@moon> <20130812145720.3b722b066fe1bd77291331e5@linux-foundation.org> <20130813050213.GA2869@moon> <520A4D5F.6020401@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <520A4D5F.6020401@zytor.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1077 Lines: 28 On Tue, Aug 13, 2013 at 08:14:39AM -0700, H. Peter Anvin wrote: > On 08/12/2013 10:02 PM, Cyrill Gorcunov wrote: > > > > There is a case when you don't need a mask completely. And because this > > pte conversion is on hot path and time critical I kept generated code > > as it was (even if that lead to slightly less clear source code). > > > > Does it actually matter, generated-code-wise, or is the compiler smart > enough to figure it out? The reason I'm asking is because it makes the gcc-4.7.2 is smart enough to suppress useless masking (ie ((1u << 31) - 1)) completely but I don't know if this can be assumed for all gcc series. > code much harder to follow. I see. OK, I'll try to prepare more readable macro helpers. > > The other thing is can we please pretty please call it something other > than "frob"? Sure. -- 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/