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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 2B191C433FF for ; Wed, 14 Aug 2019 16:07:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0046C208C2 for ; Wed, 14 Aug 2019 16:07:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565798876; bh=s3SOplqsGkMSWSphnX3KTQmhyKhK8KEfjFpxgd7RDqc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=NmHsQdvGt77ur/vMv46NOkWx2rvImPYzmIkvX56AZ902NKMeeYMVPDISJBMDR93yk hwswPqTVXLoi/WIfYCFuE/aYYtmRSrZyzjuo4UjKoW7GvDGPpHEZ20k8PqyIZk6h76 cG/GJx4Oh1Gj/OM1tIcnX2tK/mMW1zWa63y4XJYM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728344AbfHNQHy (ORCPT ); Wed, 14 Aug 2019 12:07:54 -0400 Received: from mx2.suse.de ([195.135.220.15]:37950 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726047AbfHNQHy (ORCPT ); Wed, 14 Aug 2019 12:07:54 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 61C21AB92; Wed, 14 Aug 2019 16:07:53 +0000 (UTC) Date: Wed, 14 Aug 2019 18:07:51 +0200 From: Michal Hocko To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Oscar Salvador , Pavel Tatashin , Dan Williams Subject: Re: [PATCH v2 3/5] mm/memory_hotplug: Simplify online_pages_range() Message-ID: <20190814160751.GI17933@dhcp22.suse.cz> References: <20190814154109.3448-1-david@redhat.com> <20190814154109.3448-4-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190814154109.3448-4-david@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 14-08-19 17:41:07, David Hildenbrand wrote: > online_pages always corresponds to nr_pages. Simplify the code, getting > rid of online_pages_blocks(). Add some comments. > > Cc: Andrew Morton > Cc: Oscar Salvador > Cc: Michal Hocko > Cc: Pavel Tatashin > Cc: Dan Williams > Signed-off-by: David Hildenbrand Acked-by: Michal Hocko Thanks! > --- > mm/memory_hotplug.c | 36 ++++++++++++++++-------------------- > 1 file changed, 16 insertions(+), 20 deletions(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 10ad970f3f14..63b1775f7cf8 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -632,31 +632,27 @@ static void generic_online_page(struct page *page, unsigned int order) > #endif > } > > -static int online_pages_blocks(unsigned long start, unsigned long nr_pages) > -{ > - unsigned long end = start + nr_pages; > - int order, onlined_pages = 0; > - > - while (start < end) { > - order = min(MAX_ORDER - 1, > - get_order(PFN_PHYS(end) - PFN_PHYS(start))); > - (*online_page_callback)(pfn_to_page(start), order); > - > - onlined_pages += (1UL << order); > - start += (1UL << order); > - } > - return onlined_pages; > -} > - > static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages, > void *arg) > { > - unsigned long onlined_pages = *(unsigned long *)arg; > + const unsigned long end_pfn = start_pfn + nr_pages; > + unsigned long pfn; > + int order; > + > + /* > + * Online the pages. The callback might decide to keep some pages > + * PG_reserved (to add them to the buddy later), but we still account > + * them as being online/belonging to this zone ("present"). > + */ > + for (pfn = start_pfn; pfn < end_pfn; pfn += 1ul << order) { > + order = min(MAX_ORDER - 1, get_order(PFN_PHYS(end_pfn - pfn))); > + (*online_page_callback)(pfn_to_page(pfn), order); > + } > > - onlined_pages += online_pages_blocks(start_pfn, nr_pages); > - online_mem_sections(start_pfn, start_pfn + nr_pages); > + /* mark all involved sections as online */ > + online_mem_sections(start_pfn, end_pfn); > > - *(unsigned long *)arg = onlined_pages; > + *(unsigned long *)arg += nr_pages; > return 0; > } > > -- > 2.21.0 > -- Michal Hocko SUSE Labs