From patchwork Tue Apr 7 03:06:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 11477281 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7011792A for ; Tue, 7 Apr 2020 03:06:57 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 33A8C20801 for ; Tue, 7 Apr 2020 03:06:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="IyrKVTA+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 33A8C20801 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0DF408E003D; Mon, 6 Apr 2020 23:06:56 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 068218E0001; Mon, 6 Apr 2020 23:06:55 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E74558E003D; Mon, 6 Apr 2020 23:06:55 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0240.hostedemail.com [216.40.44.240]) by kanga.kvack.org (Postfix) with ESMTP id CA1778E0001 for ; Mon, 6 Apr 2020 23:06:55 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 992CE99B4 for ; Tue, 7 Apr 2020 03:06:55 +0000 (UTC) X-FDA: 76679571990.08.start54_76a55519eeb19 X-Spam-Summary: 2,0,0,706b4e477a5dccd6,d41d8cd98f00b204,akpm@linux-foundation.org,,RULES_HIT:41:355:379:421:560:800:960:967:968:973:988:989:1260:1263:1345:1359:1381:1431:1437:1534:1541:1711:1730:1747:1777:1792:2393:2525:2559:2563:2682:2685:2859:2902:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3352:3503:3504:3865:3866:3867:3868:3870:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4321:5007:6119:6261:6653:6737:7514:7576:7903:8599:9025:9545:10004:10913:11026:11473:11658:11914:12043:12048:12297:12517:12519:12555:12679:12783:12986:13069:13161:13229:13255:13311:13357:13846:14181:14384:14721:14849:21080:21451:21627:21939:30034:30054:30064,0,RBL:198.145.29.99:@linux-foundation.org:.lbl8.mailshell.net-64.100.201.201 62.2.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:1,LUA_SUMMARY:none X-HE-Tag: start54_76a55519eeb19 X-Filterd-Recvd-Size: 3229 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf41.hostedemail.com (Postfix) with ESMTP for ; Tue, 7 Apr 2020 03:06:55 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2CD00215A4; Tue, 7 Apr 2020 03:06:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586228814; bh=E9Tai8+viH+9WOCLSIXDTax+aR2CLqEaIVCMbuSsNiE=; h=Date:From:To:Subject:In-Reply-To:From; b=IyrKVTA++d0J7QjyupqzDF1B2d3BAroE7lUy+kG6fNLWjrsB0Xjxe+eP3ugd1RxSf c/h67OJYyj4XqqGZnsA7WFMnJfIgI1h/pskVr78M+bfGblyHgNnwpgKFYjtpYhpQZS PNZj1KNGCPKNlb9wlAF7lauvaK3YO3dMFeeW3gJI= Date: Mon, 06 Apr 2020 20:06:53 -0700 From: Andrew Morton To: akpm@linux-foundation.org, bhe@redhat.com, dan.j.williams@intel.com, david@redhat.com, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, osalvador@suse.de, richard.weiyang@gmail.com, segher@kernel.crashing.org, torvalds@linux-foundation.org Subject: [patch 056/166] mm/memory_hotplug.c: simplify calculation of number of pages in __remove_pages() Message-ID: <20200407030653.PJ_dMcGKr%akpm@linux-foundation.org> In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> User-Agent: s-nail v14.8.16 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: From: David Hildenbrand Subject: mm/memory_hotplug.c: simplify calculation of number of pages in __remove_pages() In commit 52fb87c81f11 ("mm/memory_hotplug: cleanup __remove_pages()"), we cleaned up __remove_pages(), and introduced a shorter variant to calculate the number of pages to the next section boundary. Turns out we can make this calculation easier to read. We always want to have the number of pages (> 0) to the next section boundary, starting from the current pfn. We'll clean up __remove_pages() in a follow-up patch and directly make use of this computation. Link: http://lkml.kernel.org/r/20200228095819.10750-2-david@redhat.com Signed-off-by: David Hildenbrand Suggested-by: Segher Boessenkool Reviewed-by: Baoquan He Reviewed-by: Wei Yang Cc: Oscar Salvador Cc: Michal Hocko Cc: Dan Williams Signed-off-by: Andrew Morton --- mm/memory_hotplug.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/memory_hotplug.c~mm-memory_hotplug-simplify-calculation-of-number-of-pages-in-__remove_pages +++ a/mm/memory_hotplug.c @@ -534,7 +534,8 @@ void __remove_pages(unsigned long pfn, u 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; }