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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62C40C433EF for ; Wed, 29 Dec 2021 14:53:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 55C116B0071; Wed, 29 Dec 2021 09:53:40 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 4E4856B0073; Wed, 29 Dec 2021 09:53:40 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 35E8D6B0074; Wed, 29 Dec 2021 09:53:40 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0050.hostedemail.com [216.40.44.50]) by kanga.kvack.org (Postfix) with ESMTP id 216936B0071 for ; Wed, 29 Dec 2021 09:53:40 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id B767B89B3B for ; Wed, 29 Dec 2021 14:53:39 +0000 (UTC) X-FDA: 78971125758.05.8B36B74 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by imf17.hostedemail.com (Postfix) with ESMTP id C9BD340002 for ; Wed, 29 Dec 2021 14:53:22 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id DB4E621109; Wed, 29 Dec 2021 14:53:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1640789617; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=AGrhUF/lzKRcwDX1Q/od0fjVGpbS2+6A5chATdaD0Xo=; b=V69ogZWOz8qlnop+B5C7pygFjg9p230q9LePR7BjnqgBQoWImLvLHyz5wm5ThBxIF8i3BF 3qRlGONc3wzikXEl0LybXycYe3ok4cVYzOBwEOvD0onu89Dg3AYyei7k7FfYoG/Ra4bNJg 2cskwNXiv5bkgefJCANWs6wcjDzi1AI= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1640789617; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=AGrhUF/lzKRcwDX1Q/od0fjVGpbS2+6A5chATdaD0Xo=; b=nkrUSUjVX8YXSQXjtNesPIMxwQuMYxjZ11AVzoJj/pxorvpdb6wM+oTtbcn9TVw3pq38Py RtVLYH4c+3r8WYBQ== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 6927413BC1; Wed, 29 Dec 2021 14:53:37 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id qaVvFnF2zGH6WwAAMHmgww (envelope-from ); Wed, 29 Dec 2021 14:53:37 +0000 Date: Wed, 29 Dec 2021 15:53:35 +0100 From: Oscar Salvador To: Chen Wandun Cc: akpm@linux-foundation.org, vbabka@suse.cz, iamjoonsoo.kim@lge.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, wangkefeng.wang@huawei.com Subject: Re: [PATCH] mm/page_isolation: unset migratetype directly for non Buddy page Message-ID: References: <20211229033649.2760586-1-chenwandun@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211229033649.2760586-1-chenwandun@huawei.com> X-Rspamd-Queue-Id: C9BD340002 X-Stat-Signature: ox3kjz5age1qxt5wjfz77j9jffk5k191 Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=V69ogZWO; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=nkrUSUjV; dmarc=pass (policy=none) header.from=suse.de; spf=pass (imf17.hostedemail.com: domain of osalvador@suse.de designates 195.135.220.28 as permitted sender) smtp.mailfrom=osalvador@suse.de X-Rspamd-Server: rspam02 X-HE-Tag: 1640789602-385222 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 Wed, Dec 29, 2021 at 11:36:49AM +0800, Chen Wandun wrote: > There is no need to try to move_freepages_block for pages that is not > in buddy in function unset_migratetype_isolate, it can directly set > migrate type. The above could benefit from some rephrasing, someting along these lines maybe? "In unset_migratetype_isolate(), we can bypass the call to move_freepages_block() for non-buddy pages" > > It will save a few cpu cycles for some situations such as cma and > hugetlb when allocating continue pages, in these situation function > alloc_contig_pages will be called. > > alloc_contig_pages > __alloc_contig_migrate_range > isolate_freepages_range ==> pages has been remove from buddy > undo_isolate_page_range > unset_migratetype_isolate ==> can directly set migratetype > > Fixes: 3c605096d315 ("mm/page_alloc: restrict max order of merging on isolated pageblock") > Signed-off-by: Chen Wandun I am ok with the "fix", but I don't think this deserves a Fixes tag. Sure, it can spare some cpu cycles, but besides that, there is no harm in the actual code unless I missed something. Others might feel stronger about that. Reviewed-by: Oscar Salvador -- Oscar Salvador SUSE Labs