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=-5.4 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 EE551C433DB for ; Fri, 5 Feb 2021 14:29:51 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4A1E0650D7 for ; Fri, 5 Feb 2021 14:29:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4A1E0650D7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34456 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l827J-0001Xc-Ud for qemu-devel@archiver.kernel.org; Fri, 05 Feb 2021 09:29:49 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:38628) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l826E-0000cT-7t for qemu-devel@nongnu.org; Fri, 05 Feb 2021 09:28:42 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:21878) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l826C-0003kp-OS for qemu-devel@nongnu.org; Fri, 05 Feb 2021 09:28:41 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612535319; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lBUVAxXgXUpb0FtTR5yhqX4TjqKgcrbnm9Akzr5taC0=; b=JazhfyAun4xJ1xmW6Q25AO8ysKX794+Ilvp7WVgoJVEMle3rzWHK+pHp2UT74U0dfu66ZF q/GXaU15B1AsPOPrUIzoQvUgzCQ6lIlBw2hYGO/bEP38pnforIm9g50dP83mnEB1mu5WSx bwyV7L3n7yY/cUEzS1AMvmEsaBm7Kfo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-538-wWvzg-L0OPCxz8O370Ux_A-1; Fri, 05 Feb 2021 09:28:36 -0500 X-MC-Unique: wWvzg-L0OPCxz8O370Ux_A-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EEC2310CE780; Fri, 5 Feb 2021 14:28:34 +0000 (UTC) Received: from [10.3.112.253] (ovpn-112-253.phx2.redhat.com [10.3.112.253]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9A2AE679EE; Fri, 5 Feb 2021 14:28:31 +0000 (UTC) Subject: Re: [PATCH 3/3] utils: Deprecate inexact fractional suffix sizes To: =?UTF-8?Q?Daniel_P=2e_Berrang=c3=a9?= References: <20210204190708.1306296-1-eblake@redhat.com> <20210204190708.1306296-4-eblake@redhat.com> <20210205111036.GE908621@redhat.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: Date: Fri, 5 Feb 2021 08:28:31 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.0 MIME-Version: 1.0 In-Reply-To: <20210205111036.GE908621@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.352, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.33, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: vsementsov@virtuozzo.com, qemu-block@nongnu.org, rjones@redhat.com, tao3.xu@intel.com, armbru@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2/5/21 5:10 AM, Daniel P. Berrangé wrote: > On Thu, Feb 04, 2021 at 01:07:08PM -0600, Eric Blake wrote: >> The value '1.1k' is inexact; 1126.4 bytes is not possible, so we >> happen to truncate it to 1126. Our use of fractional sizes is >> intended for convenience, but when a user specifies a fraction that is >> not a clean translation to binary, truncating/rounding behind their >> backs can cause confusion. Better is to deprecate inexact values, >> which still leaves '1.5k' as valid, but alerts the user to spell out >> their values as a precise byte number in cases where they are >> currently being rounded. > > I don't think we should be deprecating this, as I think it makes > it very user hostile. Users who require exact answers, won't be > using fractional syntax in the first place. IOW, by using fractional > syntax you've decided that approximation is acceptable. Given that, > I should not have to worry about whether or not the fraction I'm > using is exact or truncated. It is horrible usability to say that > "1.1k" is invalid, while "1.5k" is valid - both are valid from my > POV as a user of this. > > > >> Note that values like '0.1G' in the testsuite need adjustment as a >> result. >> >> Sadly, since qemu_strtosz() does not have an Err** parameter, we >> pollute to stderr. > > This is only an warning, so setting an Err ** would not be appropriate > right now. > > None the less we should add an Err **, because many of the callers > want an Err ** object populated, or use error_report(). That is more effort. What's the consensus - is it important enough that I should spend that effort getting rid of technical debt by adding versions of qemu_strto* that take Err** at this point in time? -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org