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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,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 A24C0ECE587 for ; Tue, 1 Oct 2019 14:41:38 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 664522190F for ; Tue, 1 Oct 2019 14:41:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 664522190F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 183F68E000D; Tue, 1 Oct 2019 10:41:38 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 132EE8E0005; Tue, 1 Oct 2019 10:41:38 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 06F668E000D; Tue, 1 Oct 2019 10:41:38 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0128.hostedemail.com [216.40.44.128]) by kanga.kvack.org (Postfix) with ESMTP id D5B2A8E0005 for ; Tue, 1 Oct 2019 10:41:37 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id 8C32855FA5 for ; Tue, 1 Oct 2019 14:41:37 +0000 (UTC) X-FDA: 75995479434.28.maid61_828c25783bd43 X-HE-Tag: maid61_828c25783bd43 X-Filterd-Recvd-Size: 3951 Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Tue, 1 Oct 2019 14:41:36 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B3213316E536; Tue, 1 Oct 2019 14:41:35 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-54.ams2.redhat.com [10.36.116.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 117335D9C9; Tue, 1 Oct 2019 14:41:32 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , Wei Yang Subject: [PATCH v5 08/10] mm/memory_hotplug: Don't check for "all holes" in shrink_zone_span() Date: Tue, 1 Oct 2019 16:40:09 +0200 Message-Id: <20191001144011.3801-9-david@redhat.com> In-Reply-To: <20191001144011.3801-1-david@redhat.com> References: <20191001144011.3801-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Tue, 01 Oct 2019 14:41:35 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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: If we have holes, the holes will automatically get detected and removed once we remove the next bigger/smaller section. The extra checks can go. Cc: Andrew Morton Cc: Oscar Salvador Cc: Michal Hocko Cc: David Hildenbrand Cc: Pavel Tatashin Cc: Dan Williams Cc: Wei Yang Signed-off-by: David Hildenbrand --- mm/memory_hotplug.c | 34 +++++++--------------------------- 1 file changed, 7 insertions(+), 27 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 273833612774..22b3623768c8 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -393,6 +393,9 @@ static void shrink_zone_span(struct zone *zone, unsig= ned long start_pfn, if (pfn) { zone->zone_start_pfn =3D pfn; zone->spanned_pages =3D zone_end_pfn - pfn; + } else { + zone->zone_start_pfn =3D 0; + zone->spanned_pages =3D 0; } } else if (zone_end_pfn =3D=3D end_pfn) { /* @@ -405,34 +408,11 @@ static void shrink_zone_span(struct zone *zone, uns= igned long start_pfn, start_pfn); if (pfn) zone->spanned_pages =3D pfn - zone_start_pfn + 1; + else { + zone->zone_start_pfn =3D 0; + zone->spanned_pages =3D 0; + } } - - /* - * The section is not biggest or smallest mem_section in the zone, it - * only creates a hole in the zone. So in this case, we need not - * change the zone. But perhaps, the zone has only hole data. Thus - * it check the zone has only hole or not. - */ - pfn =3D zone_start_pfn; - for (; pfn < zone_end_pfn; pfn +=3D PAGES_PER_SUBSECTION) { - if (unlikely(!pfn_to_online_page(pfn))) - continue; - - if (page_zone(pfn_to_page(pfn)) !=3D zone) - continue; - - /* Skip range to be removed */ - if (pfn >=3D start_pfn && pfn < end_pfn) - continue; - - /* If we find valid section, we have nothing to do */ - zone_span_writeunlock(zone); - return; - } - - /* The zone has no valid section */ - zone->zone_start_pfn =3D 0; - zone->spanned_pages =3D 0; zone_span_writeunlock(zone); } =20 --=20 2.21.0