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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 E1D50C352AA for ; Tue, 1 Oct 2019 11:37:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC6C02133F for ; Tue, 1 Oct 2019 11:37:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731466AbfJALhA (ORCPT ); Tue, 1 Oct 2019 07:37:00 -0400 Received: from mga04.intel.com ([192.55.52.120]:46171 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725951AbfJALhA (ORCPT ); Tue, 1 Oct 2019 07:37:00 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 01 Oct 2019 04:36:59 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,571,1559545200"; d="scan'208";a="191434426" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.40]) by fmsmga007.fm.intel.com with ESMTP; 01 Oct 2019 04:36:57 -0700 Received: from andy by smile with local (Exim 4.92.2) (envelope-from ) id 1iFGSd-0008Ar-Jv; Tue, 01 Oct 2019 14:36:55 +0300 Date: Tue, 1 Oct 2019 14:36:55 +0300 From: Andy Shevchenko To: Alexandre Belloni Cc: Petr Mladek , linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Hans Verkuil , Mathias Nyman , Jonathan Corbet , Thierry Reding , Jonathan Hunter , John Stultz , Thomas Gleixner Subject: Re: [PATCH v1 1/4] lib/vsprintf: Print time64_t in human readable format Message-ID: <20191001113655.GI32742@smile.fi.intel.com> References: <20190104193009.30907-1-andriy.shevchenko@linux.intel.com> <20190108152528.utr3a5huran52gsf@pathway.suse.cz> <20190110215858.GG2362@piout.net> <20190726132037.GX9224@smile.fi.intel.com> <20190930200809.GK3913@piout.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190930200809.GK3913@piout.net> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 30, 2019 at 10:08:09PM +0200, Alexandre Belloni wrote: > On 26/07/2019 16:20:37+0300, Andy Shevchenko wrote: > > On Thu, Jan 10, 2019 at 10:58:58PM +0100, Alexandre Belloni wrote: > > > On 08/01/2019 16:25:28+0100, Petr Mladek wrote: > > > > On Fri 2019-01-04 21:30:06, Andy Shevchenko wrote: > > > > > There are users which print time and date represented by content of > > > > > time64_t type in human readable format. > > > > > > > > > > Instead of open coding that each time introduce %ptT[dt][r] specifier. > > > > > > > > > > Few test cases for %ptT specifier has been added as well. > > > > > > > +void time64_to_rtc_time(time64_t time, struct rtc_time *rtc_time) > > > > > +{ > > > > > +#ifdef CONFIG_RTC_LIB > > > > > + rtc_time64_to_tm(time, rtc_time); > > > > > > I wonder if the conversion between struct tm and rtc_time > > > > might be useful in general. > > > > > > > > It might make sense to de-duplicate time64_to_tm() and > > > > rtc_time64_to_tm() implementations. > > > > > Looking at 57f1f0874f42, this seemed to be the plan at the time > > > time_to_tm was introduced but this was never done. Seeing that tm and > > > rtc_time are quite similar, we could probably always use time64_to_tm as > > > it is more accurate than rtc_time64_to_tm as the latter assumes a > > > specific year range. > > > > So, do I understand correctly that dropping #ifdef along with > > rtc_time64_to_tm() call is sufficient for now? > > > > I'd be fine with that. Good, thanks! I'll send v2 soon. > > > Maybe be rtc_str should take a struct tm instead of an rtc_time so > > > time64_to_rtc_time always uses time64_to_tm. > > > > Because this one, while sounding plausible, maybe too invasive on current > > state of affairs. > > Well, if the kernel struct tm had an int tm_year instead of long > tm_year, then you could simply cast a struct rtc_time to a struct tm. I don't think so. It will be error prone from endianess prospective on 64-bit platforms. > I'm not sure was was the rationale to have a long, especially since > userspace has an int. Yeah, this is strange, I guess we simple may long -> int in kernel's struct tm. -- With Best Regards, Andy Shevchenko