From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A213C2BA2B for ; Thu, 9 Apr 2020 13:26:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0CF3C20857 for ; Thu, 9 Apr 2020 13:26:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586438802; bh=cV6hSehyX6lw4Tv9+IglB58tggNYFJ6BalVHwJs8cI8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=L2pEdJFhEwczuy1J0OHqB8j0J2UE/rqrk144eFwrtk9yHv6fZjWDQ14sQLjr3EAHl dYRcjQzgwNMXzGZlViaKK8i+W+BWP8TguqIVbLxCU/8IlTu95t/qF3oBqxGK7VDk9o i/zDybVW5XBdYZK21q49twj2RRRBdB1TCyH1dtNQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726786AbgDIN0l (ORCPT ); Thu, 9 Apr 2020 09:26:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:48448 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726681AbgDIN0l (ORCPT ); Thu, 9 Apr 2020 09:26:41 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 62E882072F; Thu, 9 Apr 2020 13:26:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586438801; bh=cV6hSehyX6lw4Tv9+IglB58tggNYFJ6BalVHwJs8cI8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=H9uzvWqkZoza1WwcQy6lLYj+vDp8hvrlgELwPMjzCUzfYJ5JZZHkeINQiHfngaRFe 7WOLZlaXP9ZxF2dUO/OHweSokzXySPzG3A+GzKiIDeTCRFX6R5SSdhlywofkdfwzLU IdwaSKjwyHFZtTWRiPWDOJOI9+eAPT6vkZvZF0Jk= Date: Thu, 9 Apr 2020 14:26:34 +0100 From: Will Deacon To: Vincenzo Frascino Cc: Catalin Marinas , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, clang-built-linux@googlegroups.com, x86@kernel.org, Will Deacon , Arnd Bergmann , Russell King , Paul Burton , Thomas Gleixner , Andy Lutomirski , Ingo Molnar , Borislav Petkov , Stephen Boyd , Mark Salyzyn , Kees Cook , Peter Collingbourne , Dmitry Safonov <0x7f454c46@gmail.com>, Andrei Vagin , Nick Desaulniers , Marc Zyngier , Mark Rutland Subject: Re: [PATCH v3 21/26] arm64: Introduce asm/vdso/arch_timer.h Message-ID: <20200409132633.GD13078@willie-the-truck> References: <20200313154345.56760-1-vincenzo.frascino@arm.com> <20200313154345.56760-22-vincenzo.frascino@arm.com> <20200315183151.GE32205@mbp> <4914ad9c-3eaf-b328-f31b-5d3077ef272f@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4914ad9c-3eaf-b328-f31b-5d3077ef272f@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Hi Vincenzo, Sorry, I was on holiday when you posted this and it slipped through the cracks. On Mon, Mar 16, 2020 at 03:37:23PM +0000, Vincenzo Frascino wrote: > > On Fri, Mar 13, 2020 at 03:43:40PM +0000, Vincenzo Frascino wrote: > >> The vDSO library should only include the necessary headers required for > >> a userspace library (UAPI and a minimal set of kernel headers). To make > >> this possible it is necessary to isolate from the kernel headers the > >> common parts that are strictly necessary to build the library. > >> > >> Introduce asm/vdso/arch_timer.h to contain all the arm64 specific > >> code. This allows to replace the second isb() in __arch_get_hw_counter() > >> with a fake dependent stack read of the counter which improves the vdso > >> library peformances of ~4.5%. Below the results of vdsotest [1] ran for > >> 100 iterations. > > > > The subject seems to imply a non-functional change but as you read, it > > gets a lot more complicated. Could you keep the functional change > > separate from the header clean-up, maybe submit it as an independent > > patch? And it shouldn't go in without Will's ack ;). > > > > It is fine by me. I will repost the series with the required fixes and without > this patch. This will give to me enough time to address Mark's comments as well > and to Will to have a proper look. Please can you post whatever is left at -rc1? I'll have a look then, but let's stick to just moving code around rather than randomly changing it at the same time, ok? Thanks, Will