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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 6D770C04AB5 for ; Mon, 3 Jun 2019 13:48:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 47555242DD for ; Mon, 3 Jun 2019 13:48:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728425AbfFCNsF (ORCPT ); Mon, 3 Jun 2019 09:48:05 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:51430 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727645AbfFCNsF (ORCPT ); Mon, 3 Jun 2019 09:48:05 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6583E15A2; Mon, 3 Jun 2019 06:48:04 -0700 (PDT) Received: from [10.1.196.75] (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 45F5B3F246; Mon, 3 Jun 2019 06:48:03 -0700 (PDT) Subject: Re: [PATCH] iommu: replace single-char identifiers in macros To: Qian Cai , jroedel@suse.de Cc: akpm@linux-foundation.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org References: <1559566783-13627-1-git-send-email-cai@lca.pw> <1559568571.6132.42.camel@lca.pw> From: Robin Murphy Message-ID: Date: Mon, 3 Jun 2019 14:48:01 +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: <1559568571.6132.42.camel@lca.pw> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/06/2019 14:29, Qian Cai wrote: > On Mon, 2019-06-03 at 14:07 +0100, Robin Murphy wrote: >> On 03/06/2019 13:59, Qian Cai wrote: >>> There are a few macros in IOMMU have single-char identifiers make the >>> code hard to read and debug. Replace them with meaningful names. >>> >>> Suggested-by: Andrew Morton >>> Signed-off-by: Qian Cai >>> --- >>>   include/linux/dmar.h | 14 ++++++++------ >>>   1 file changed, 8 insertions(+), 6 deletions(-) >>> >>> diff --git a/include/linux/dmar.h b/include/linux/dmar.h >>> index f8af1d770520..eb634912f475 100644 >>> --- a/include/linux/dmar.h >>> +++ b/include/linux/dmar.h >>> @@ -104,12 +104,14 @@ static inline bool dmar_rcu_check(void) >>> >>>   #define dmar_rcu_dereference(p) rcu_dereference_check((p), >>> dmar_rcu_check()) >>> >>> -#define for_each_dev_scope(a, c, p, d) \ >>> - for ((p) = 0; ((d) = (p) < (c) ? dmar_rcu_dereference((a)[(p)].dev) >>> : \ >>> - NULL, (p) < (c)); (p)++) >>> - >>> -#define for_each_active_dev_scope(a, c, p, d) \ >>> - for_each_dev_scope((a), (c), (p), (d)) if (!(d)) { continue; >>> } else >>> +#define for_each_dev_scope(devs, cnt, i, tmp) >>> \ >>> + for ((i) = 0; ((tmp) = (i) < (cnt) ? >>> \ >> >> Given that "tmp" actually appears to be some sort of device cursor, I'm >> not sure that that naming really achieves the stated goal of clarity :/ > > "tmp" is used in the callers everywhere though, although I suppose something > like "tmp_dev" can be used if you prefer. I don't have any preference, I'm just questioning the assertion in the commit message - as a reader not intimately familiar with this code, "tmp" is honestly no more meaningful than "d" was. Robin.