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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 10A35C352A1 for ; Thu, 6 Feb 2020 01:46:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA23920658 for ; Thu, 6 Feb 2020 01:46:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="RlzdZLPU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727605AbgBFBq4 (ORCPT ); Wed, 5 Feb 2020 20:46:56 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:54116 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727170AbgBFBqz (ORCPT ); Wed, 5 Feb 2020 20:46:55 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580953614; h=from:from:reply-to:subject:subject: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=QFMZVwYTnIpL7fCFcXZb1GizaNxHu6MTVpIRsyiA0gQ=; b=RlzdZLPUl5L2d8CZkKUhvMdXjAGtEhk29SH/M0EZcTTNWSaopmSUMZxb4RR8EgsQY7hnzz o3az559rtRnNWG64hEpWZUavLF7q2UEEr/Y87EA/XvnJjFndVJoledf0kUvi7XzpBOi7Fj CAO0KPIe7dHRdxRgt2K15w7XtybFdiw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-213-FQ5uAGHWOuGLBy3AOFBdww-1; Wed, 05 Feb 2020 20:46:50 -0500 X-MC-Unique: FQ5uAGHWOuGLBy3AOFBdww-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B9A4F10753F3; Thu, 6 Feb 2020 01:46:48 +0000 (UTC) Received: from localhost (ovpn-12-19.pek2.redhat.com [10.72.12.19]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F0B271A7E3; Thu, 6 Feb 2020 01:46:45 +0000 (UTC) Date: Thu, 6 Feb 2020 09:46:42 +0800 From: Baoquan He To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Segher Boessenkool , Andrew Morton , Michal Hocko , Oscar Salvador , Wei Yang Subject: Re: [PATCH v1] mm/memory_hotplug: Easier calculation to get pages to next section boundary Message-ID: <20200206014642.GJ8965@MiWiFi-R3L-srv> References: <20200205135251.37488-1-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200205135251.37488-1-david@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/05/20 at 02:52pm, David Hildenbrand wrote: > Let's use a calculation that's easier to understand and calculates the > same result. Reusing existing macros makes this look nicer. > > We always want to have the number of pages (> 0) to the next section > boundary, starting from the current pfn. > > Suggested-by: Segher Boessenkool > Cc: Andrew Morton > Cc: Michal Hocko > Cc: Oscar Salvador > Cc: Baoquan He > Cc: Wei Yang > Signed-off-by: David Hildenbrand LGTM. Reviewed-by: Baoquan He > --- > mm/memory_hotplug.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 0a54ffac8c68..c30191183c04 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -528,7 +528,8 @@ void __remove_pages(unsigned long pfn, unsigned long nr_pages, > for (; pfn < end_pfn; pfn += cur_nr_pages) { > cond_resched(); > /* Select all remaining pages up to the next section boundary */ > - cur_nr_pages = min(end_pfn - pfn, -(pfn | PAGE_SECTION_MASK)); > + cur_nr_pages = min(end_pfn - pfn, > + SECTION_ALIGN_UP(pfn + 1) - pfn); > __remove_section(pfn, cur_nr_pages, map_offset, altmap); > map_offset = 0; > } > -- > 2.24.1 >