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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63EE1C77B73 for ; Sat, 27 May 2023 08:00:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229819AbjE0IAl (ORCPT ); Sat, 27 May 2023 04:00:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47294 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229529AbjE0IAh (ORCPT ); Sat, 27 May 2023 04:00:37 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B7A5B2 for ; Sat, 27 May 2023 01:00:36 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 915B661013 for ; Sat, 27 May 2023 08:00:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE395C433D2; Sat, 27 May 2023 08:00:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685174434; bh=1IJdM/Bry22ESZ9un0C7ZvpkLJqgF412vz9PcaQjdIg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rrCI02dryYG9OHO3mYKo2BBgLeIlw+ElNUV0aH9Wdc/NH2b+J5QIdIGXJexUS5sNW +JMj5YGpSOLFP+yOoBAso0dUSDDFSrfOQOPGYZruEwUHLV/pAizUbs/n5SPx+1rEZ7 +YEHSd4tlKNmlGsRfmPCj5ufH3dYpSVv9RMIAyb6+72bpvhbqnTyhVL6KrMAv8Db2Y S7mgF2AbAwDtFYfIFZhvuyNK5skvr+CzUwRFmqibpVRT8xjAbjiQD9fQC7zv6IFBsP 6tQxC0qR+rp7FUB99VtQTeh5YSkQcxAPWYVd9NElX3tcssMp7qesq1X2cCaKu0EBlC K+W/iSib06T8A== Date: Sat, 27 May 2023 11:00:14 +0300 From: Mike Rapoport To: Haifeng Xu Cc: akpm@linux-foundation.org, mhocko@suse.com, david@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] mm/mm_init.c: do not calculate zone_start_pfn/zone_end_pfn in zone_absent_pages_in_node() Message-ID: <20230527080014.GD4967@kernel.org> References: <20230526085251.1977-2-haifeng.xu@shopee.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230526085251.1977-2-haifeng.xu@shopee.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 26, 2023 at 08:52:51AM +0000, Haifeng Xu wrote: > In calculate_node_totalpages(), zone_start_pfn/zone_end_pfn are already > calculated in zone_spanned_pages_in_node(), so use them as parameters > instead of node_start_pfn/node_end_pfn and the duplicated calculation > process can de dropped. > > Signed-off-by: Haifeng Xu > Suggested-by: Mike Rapoport Reviewed-by: Mike Rapoport (IBM) > --- > v2: > - remove unrelated whitespace changes > - do not replace pgdat->node_id with a local > variable > - remove redundant variable 'size' > - add check that whether a zone is empty or not > --- > mm/mm_init.c | 30 ++++++++++++------------------ > 1 file changed, 12 insertions(+), 18 deletions(-) > > diff --git a/mm/mm_init.c b/mm/mm_init.c > index f674e5798f7d..2d91bb52c619 100644 > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -1166,20 +1166,15 @@ unsigned long __init absent_pages_in_range(unsigned long start_pfn, > /* Return the number of page frames in holes in a zone on a node */ > static unsigned long __init zone_absent_pages_in_node(int nid, > unsigned long zone_type, > - unsigned long node_start_pfn, > - unsigned long node_end_pfn) > + unsigned long zone_start_pfn, > + unsigned long zone_end_pfn) > { > - unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; > - unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; > - unsigned long zone_start_pfn, zone_end_pfn; > unsigned long nr_absent; > > - zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); > - zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); > + /* zone is empty, we don't have any absent pages */ > + if (zone_start_pfn == zone_end_pfn) > + return 0; > > - adjust_zone_range_for_zone_movable(nid, zone_type, > - node_start_pfn, node_end_pfn, > - &zone_start_pfn, &zone_end_pfn); > nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); > > /* > @@ -1272,7 +1267,7 @@ static void __init calculate_node_totalpages(struct pglist_data *pgdat, > struct zone *zone = pgdat->node_zones + i; > unsigned long zone_start_pfn, zone_end_pfn; > unsigned long spanned, absent; > - unsigned long size, real_size; > + unsigned long real_size; > > spanned = zone_spanned_pages_in_node(pgdat->node_id, i, > node_start_pfn, > @@ -1280,23 +1275,22 @@ static void __init calculate_node_totalpages(struct pglist_data *pgdat, > &zone_start_pfn, > &zone_end_pfn); > absent = zone_absent_pages_in_node(pgdat->node_id, i, > - node_start_pfn, > - node_end_pfn); > + zone_start_pfn, > + zone_end_pfn); > > - size = spanned; > - real_size = size - absent; > + real_size = spanned - absent; > > - if (size) > + if (spanned) > zone->zone_start_pfn = zone_start_pfn; > else > zone->zone_start_pfn = 0; > - zone->spanned_pages = size; > + zone->spanned_pages = spanned; > zone->present_pages = real_size; > #if defined(CONFIG_MEMORY_HOTPLUG) > zone->present_early_pages = real_size; > #endif > > - totalpages += size; > + totalpages += spanned; > realtotalpages += real_size; > } > > -- > 2.25.1 > -- Sincerely yours, Mike.