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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 5740AC282DD for ; Mon, 10 Jun 2019 11:07:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 33B6F206C3 for ; Mon, 10 Jun 2019 11:07:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388932AbfFJLHu (ORCPT ); Mon, 10 Jun 2019 07:07:50 -0400 Received: from foss.arm.com ([217.140.110.172]:40736 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388373AbfFJLHt (ORCPT ); Mon, 10 Jun 2019 07:07:49 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C949C337; Mon, 10 Jun 2019 04:07:48 -0700 (PDT) Received: from [10.1.196.72] (e119884-lin.cambridge.arm.com [10.1.196.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3D22E3F557; Mon, 10 Jun 2019 04:09:28 -0700 (PDT) Subject: Re: [PATCH v6 01/19] kernel: Standardize vdso_datapage To: Huw Davies Cc: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-kselftest@vger.kernel.org, Catalin Marinas , Will Deacon , Arnd Bergmann , Russell King , Ralf Baechle , Paul Burton , Daniel Lezcano , Thomas Gleixner , Mark Salyzyn , Peter Collingbourne , Shuah Khan , Dmitry Safonov <0x7f454c46@gmail.com>, Rasmus Villemoes References: <20190530141531.43462-1-vincenzo.frascino@arm.com> <20190530141531.43462-2-vincenzo.frascino@arm.com> <20190610092751.GA11076@merlot.physics.ox.ac.uk> <58cedde2-0d54-7d2d-f519-77cb71f543fd@arm.com> <20190610103151.GD11076@merlot.physics.ox.ac.uk> From: Vincenzo Frascino Message-ID: <83ab2758-0e8c-35d5-906a-0338bcee3310@arm.com> Date: Mon, 10 Jun 2019 12:07:45 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190610103151.GD11076@merlot.physics.ox.ac.uk> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Hi Huw, On 10/06/2019 11:31, Huw Davies wrote: > On Mon, Jun 10, 2019 at 11:17:48AM +0100, Vincenzo Frascino wrote: >> On 10/06/2019 10:27, Huw Davies wrote: >>> On Thu, May 30, 2019 at 03:15:13PM +0100, Vincenzo Frascino wrote: >>>> --- /dev/null >>>> +++ b/include/vdso/datapage.h >>>> @@ -0,0 +1,91 @@ >>>> +/* SPDX-License-Identifier: GPL-2.0 */ >>>> +#ifndef __VDSO_DATAPAGE_H >>>> +#define __VDSO_DATAPAGE_H >>>> + >>>> +#ifdef __KERNEL__ >>>> + >>>> +#ifndef __ASSEMBLY__ >>>> + >>>> +#include >>>> +#include >>>> +#include >>>> + >>>> +#define VDSO_BASES (CLOCK_TAI + 1) >>>> +#define VDSO_HRES (BIT(CLOCK_REALTIME) | \ >>>> + BIT(CLOCK_MONOTONIC) | \ >>>> + BIT(CLOCK_BOOTTIME) | \ >>>> + BIT(CLOCK_TAI)) >>>> +#define VDSO_COARSE (BIT(CLOCK_REALTIME_COARSE) | \ >>>> + BIT(CLOCK_MONOTONIC_COARSE)) >>>> +#define VDSO_RAW (BIT(CLOCK_MONOTONIC_RAW)) >>>> + >>>> +#define CS_HRES_COARSE 0 >>>> +#define CS_RAW 1 >>> >>> CS_HRES_COARSE seems like a confusing name choice to me. What you >>> really mean is not RAW. >>> >>> How about CS_ADJ to indicate that its updated by adjtime? >>> CS_XTIME might be another option. >>> >> >> I divided the timers in 3 sets (HRES, COARSE, RAW), CS_HRES_COARSE refers to the >> first two and CS_RAW to the third. I will ad a comment to explain the logic in >> the next iteration. > > I'm thinking ahead about a possible CLOCK_MONOTONIC_RAW_COARSE (which > would be useful at least for Wine). In that case you'd have four clock > types non-raw and raw, each with either hres or coarse. > Thanks for this, I was not aware of CLOCK_MONOTONIC_RAW_COARSE. I tried to find, though, some details, but I could not find any. Could you please provide some reference? > Huw. > -- Regards, Vincenzo