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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 D2B85C10F27 for ; Tue, 10 Mar 2020 08:28:52 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9150A24677 for ; Tue, 10 Mar 2020 08:28:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9150A24677 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 267766B0005; Tue, 10 Mar 2020 04:28:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 218406B0006; Tue, 10 Mar 2020 04:28:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 154EC6B0007; Tue, 10 Mar 2020 04:28:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0106.hostedemail.com [216.40.44.106]) by kanga.kvack.org (Postfix) with ESMTP id EE6CF6B0005 for ; Tue, 10 Mar 2020 04:28:51 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 9394B180AD81D for ; Tue, 10 Mar 2020 08:28:51 +0000 (UTC) X-FDA: 76578776862.14.feet49_8783ca9cf2610 X-HE-Tag: feet49_8783ca9cf2610 X-Filterd-Recvd-Size: 1749 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf35.hostedemail.com (Postfix) with ESMTP for ; Tue, 10 Mar 2020 08:28:51 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 044C5B232; Tue, 10 Mar 2020 08:28:48 +0000 (UTC) Subject: Re: [PATCH v2] mm/page_alloc: simplify page_is_buddy() for better code readability To: qiwuchen55@gmail.com, akpm@linux-foundation.org, pankaj.gupta.linux@gmail.com, alexander.duyck@gmail.com, willy@infradead.org, bhe@redhat.com Cc: linux-mm@kvack.org, chenqiwu References: <1583807664-10343-1-git-send-email-qiwuchen55@gmail.com> From: Vlastimil Babka Message-ID: <30f98262-2686-c717-8b0c-fd90c204b35d@suse.cz> Date: Tue, 10 Mar 2020 09:28:46 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <1583807664-10343-1-git-send-email-qiwuchen55@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 3/10/20 3:34 AM, qiwuchen55@gmail.com wrote: > From: chenqiwu > > Simplify page_is_buddy() to reduce the redundant code for better code > readability. > > Signed-off-by: chenqiwu I would personally keep testing the page type first, and even switch it so that PageBuddy is tested before page_is_guard (but it only matters on debugging kernels). I can only speculate which will have better performance (if any), but it's more logical to test the type first. Both orders should be safe though as we have the zone lock.