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 B63DBC433EF for ; Wed, 25 May 2022 08:34:03 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5A0FE8D0002; Wed, 25 May 2022 04:34:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5295E8D0001; Wed, 25 May 2022 04:34:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3CBA38D0002; Wed, 25 May 2022 04:34:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 2E9B38D0001 for ; Wed, 25 May 2022 04:34:03 -0400 (EDT) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id F2C5D34818 for ; Wed, 25 May 2022 08:34:02 +0000 (UTC) X-FDA: 79503602724.17.B975D11 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf18.hostedemail.com (Postfix) with ESMTP id 9CEB71C0033 for ; Wed, 25 May 2022 08:33:45 +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-out2.suse.de (Postfix) with ESMTPS id 560D31F905; Wed, 25 May 2022 08:34:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1653467641; 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=xaH39BgdZFLv03clfSyy/OuxxUwtGCud54HsOpFPD38=; b=k1xMH+7P2x++1wYvAHFCl1iClP7lpj84s0LJFpEgtNS5J8k2qdvgxABOXT7KZbruELQTYX o4KTlhZ7BXqMtwlGHBsvo/78UwFN5q9HN35MVcZNH7C62omzD0DVJsL++3+k/6qGUM4yhb Nbwa3eKArznbAu0YcixnH68fnhHA0Fg= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1653467641; 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=xaH39BgdZFLv03clfSyy/OuxxUwtGCud54HsOpFPD38=; b=AzSI7r8359ObglOZswaTCnqhc2MqekTcRDN57+fVKQ8jFDwziM85Uym/W6+s8zIJtnsHDm Z5YX8yPpW67RNRBA== 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 24D6A13ADF; Wed, 25 May 2022 08:34:00 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id f83LBPjpjWKoOAAAMHmgww (envelope-from ); Wed, 25 May 2022 08:34:00 +0000 Date: Wed, 25 May 2022 10:33:58 +0200 From: Oscar Salvador To: Miaohe Lin Cc: akpm@linux-foundation.org, mike.kravetz@oracle.com, naoya.horiguchi@nec.com, peterx@redhat.com, apopple@nvidia.com, ying.huang@intel.com, david@redhat.com, songmuchun@bytedance.com, hch@lst.de, dhowells@redhat.com, cl@linux.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/4] mm/migration: remove unneeded lock page and PageMovable check Message-ID: References: <20220525081822.53547-1-linmiaohe@huawei.com> <20220525081822.53547-3-linmiaohe@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220525081822.53547-3-linmiaohe@huawei.com> Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=k1xMH+7P; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=AzSI7r83; dmarc=pass (policy=none) header.from=suse.de; spf=pass (imf18.hostedemail.com: domain of osalvador@suse.de designates 195.135.220.29 as permitted sender) smtp.mailfrom=osalvador@suse.de X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 9CEB71C0033 X-Stat-Signature: wydgj5qtceyaxypyksdcn1srrf9niuim X-HE-Tag: 1653467625-336868 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, May 25, 2022 at 04:18:20PM +0800, Miaohe Lin wrote: > When non-lru movable page was freed from under us, __ClearPageMovable must > have been done. So we can remove unneeded lock page and PageMovable check > here. Also free_pages_prepare() will clear PG_isolated for us, so we can > further remove ClearPageIsolated as suggested by David. > > Signed-off-by: Miaohe Lin > Reviewed-by: Christoph Hellwig Reviewed-by: Oscar Salvador > --- > mm/migrate.c | 9 ++------- > 1 file changed, 2 insertions(+), 7 deletions(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index e88ebb88fa6f..337336115e43 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -1090,15 +1090,10 @@ static int unmap_and_move(new_page_t get_new_page, > return -ENOSYS; > > if (page_count(page) == 1) { > - /* page was freed from under us. So we are done. */ > + /* Page was freed from under us. So we are done. */ > ClearPageActive(page); > ClearPageUnevictable(page); > - if (unlikely(__PageMovable(page))) { > - lock_page(page); > - if (!PageMovable(page)) > - ClearPageIsolated(page); > - unlock_page(page); > - } > + /* free_pages_prepare() will clear PG_isolated. */ > goto out; > } > > -- > 2.23.0 > > -- Oscar Salvador SUSE Labs