From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030549AbaGPHU2 (ORCPT ); Wed, 16 Jul 2014 03:20:28 -0400 Received: from casper.infradead.org ([85.118.1.10]:33077 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933904AbaGPHU0 (ORCPT ); Wed, 16 Jul 2014 03:20:26 -0400 Date: Wed, 16 Jul 2014 09:20:17 +0200 From: Peter Zijlstra To: Thomas Gleixner Cc: John Stultz , LKML , Arnd Bergmann Subject: Re: [patch 14/55] timekeeping: Provide internal ktime_t based data Message-ID: <20140716072017.GV6758@twins.programming.kicks-ass.net> References: <20140711133623.530368377@linutronix.de> <20140711133706.426549845@linutronix.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="xWrScvulqIuecunV" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --xWrScvulqIuecunV Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Jul 16, 2014 at 09:12:52AM +0200, Thomas Gleixner wrote: > Looking into it I think for now it's the least risky approach to keep > the core logic based on the timespec stuff unmodified and update the > ktime_t members in timekeeping_update(). Converting the whole thing to > a pure nsec based mechanism and update the timespec stuff in > timekeeping_update() needs a lot more thought and we should do that > later on. It wont change any of the interfaces. So I don't think you can only do nsec, seeing how the conversion from nsec to timespec is expensive. So if we want to also avoid the timespec -> nsec conversion we need to keep both, no two ways around it. That said the timespec -> nsec conversion is heaps cheaper, although still not what you call really sheep ;-) --xWrScvulqIuecunV Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJTxiexAAoJEHZH4aRLwOS6JgEQALN5QvJQ8Irocf8VbUSTBVnc /CrW9qhwBfOUOnQ+2OkuEwT3Hei5a/FTctxaJCXoTQQpkAeNG2i32OBgCe4iKo6G OT5UnJ4OKqq896uHUlx45aqlB73k/K2uinVdBC0Pq3O74JzcCfIgAe/bsOM8KNPh UNIgDWNoMcu8NriYb11Aojy8HHIZcmZbOaz/zRiRGV4xyO2Rx2eiGVwe+qd58Zhc V/JwKEoMcV4vhqS3pV6jbWjG1REvmFjOuPO+vFdraDPzdXGFQbBaDW/nzC4P1uyc viOgNHgoQuJxayrys7D/4GeXK9ahDlQnavy0dvi/8KTKdUGd5yS2WqSNys/2oBBt /59PDKGIKSJhDd78DjhzC2jQ4nPIABl+vtaVSy8ziLPuz22llSRwa2RvOBTCcoVE LMal2zY4dFB8qPcJfr+c2T7CtiD2w88jCMJmtGtE0hzImIDG5lvAIeLJ05XpGAiP 2WXA3IXijLeeam/q0v2S6RCYxsbuCT+CDrA6/cZzJFUFPukbBCxN5RXdnerX6ePJ /i+gsg/8K775ltrn4yCNuQFHxDwk/Z8HuDFnIfrtGynIi/g0pCc0TOlDB9gCMozw vmd0C8dCCnYuvodS+CJYDA5Z4UjXuywMQp9byBRIZj5iJ9y0XsEuu/qBkqp7dQ7r bfj1HHYIEOV6dt6HmGxe =MLOh -----END PGP SIGNATURE----- --xWrScvulqIuecunV--