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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS 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 5D42DC43610 for ; Wed, 21 Nov 2018 01:04:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2317A2145D for ; Wed, 21 Nov 2018 01:04:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2317A2145D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726316AbeKULg4 (ORCPT ); Wed, 21 Nov 2018 06:36:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47510 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725939AbeKULgz (ORCPT ); Wed, 21 Nov 2018 06:36:55 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CC2F94E91A; Wed, 21 Nov 2018 01:04:52 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A628E5D75D; Wed, 21 Nov 2018 01:04:52 +0000 (UTC) Received: from zmail21.collab.prod.int.phx2.redhat.com (zmail21.collab.prod.int.phx2.redhat.com [10.5.83.24]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 65F5B181B9E3; Wed, 21 Nov 2018 01:04:52 +0000 (UTC) Date: Tue, 20 Nov 2018 20:04:51 -0500 (EST) From: Pankaj Gupta To: David Hildenbrand Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, devel@linuxdriverproject.org, linux-fsdevel@vger.kernel.org, linux-pm@vger.kernel.org, xen-devel@lists.xenproject.org, kexec-ml , pv-drivers@vmware.com, "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Kairui Song , Vitaly Kuznetsov , Andrew Morton , Matthew Wilcox , Michal Hocko , "Michael S. Tsirkin" Message-ID: <1155749039.35435813.1542762291980.JavaMail.zimbra@redhat.com> In-Reply-To: <1380154502.35259416.1542706636322.JavaMail.zimbra@redhat.com> References: <20181119101616.8901-1-david@redhat.com> <20181119101616.8901-6-david@redhat.com> <1747228.35250472.1542703532881.JavaMail.zimbra@redhat.com> <6258a58b-28c7-c055-0752-e8bd085b835f@redhat.com> <1380154502.35259416.1542706636322.JavaMail.zimbra@redhat.com> Subject: Re: [PATCH v1 5/8] hv_balloon: mark inflated pages PG_offline MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.116.39, 10.4.195.13] Thread-Topic: hv_balloon: mark inflated pages PG_offline Thread-Index: vwj8vPwTZelkM2IMC2vxi7m7cNxk+fJk6PaG X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Wed, 21 Nov 2018 01:04:53 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > >> --- > > >> drivers/hv/hv_balloon.c | 14 ++++++++++++-- > > >> 1 file changed, 12 insertions(+), 2 deletions(-) > > >> > > >> diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c > > >> index 211f3fe3a038..47719862e57f 100644 > > >> --- a/drivers/hv/hv_balloon.c > > >> +++ b/drivers/hv/hv_balloon.c > > >> @@ -681,8 +681,13 @@ static struct notifier_block hv_memory_nb = { > > >> /* Check if the particular page is backed and can be onlined and online > > >> it. > > >> */ > > >> static void hv_page_online_one(struct hv_hotadd_state *has, struct page > > >> *pg) > > >> { > > >> - if (!has_pfn_is_backed(has, page_to_pfn(pg))) > > >> + if (!has_pfn_is_backed(has, page_to_pfn(pg))) { > > >> + if (!PageOffline(pg)) > > >> + __SetPageOffline(pg); > > >> return; > > >> + } > > >> + if (PageOffline(pg)) > > >> + __ClearPageOffline(pg); > > >> > > >> /* This frame is currently backed; online the page. */ > > >> __online_page_set_limits(pg); > > >> @@ -1201,6 +1206,7 @@ static void free_balloon_pages(struct > > >> hv_dynmem_device > > >> *dm, > > >> > > >> for (i = 0; i < num_pages; i++) { > > >> pg = pfn_to_page(i + start_frame); > > >> + __ClearPageOffline(pg); > > > > > > Just thinking, do we need to care for clearing PageOffline flag before > > > freeing > > > a balloon'd page? > > > > Yes we have to otherwise the code will crash when trying to set PageBuddy. > > > > (only one page type at a time may be set right now, and it makes sense. > > A page that is offline cannot e.g. be a buddy page) > > o.k > > > > So PageOffline is completely managed by the page owner. > > Makes sense. Thanks for explaining. Looks good to me. Acked-by: Pankaj gupta