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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 6A53DC43142 for ; Thu, 28 Jun 2018 06:29:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2261226FB7 for ; Thu, 28 Jun 2018 06:29:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2261226FB7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753631AbeF1G3H (ORCPT ); Thu, 28 Jun 2018 02:29:07 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:59114 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751466AbeF1G3G (ORCPT ); Thu, 28 Jun 2018 02:29:06 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7936540255D7; Thu, 28 Jun 2018 06:29:05 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-8-16.pek2.redhat.com [10.72.8.16]) by smtp.corp.redhat.com (Postfix) with ESMTP id 99BF62156880; Thu, 28 Jun 2018 06:29:00 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, dave.hansen@intel.com, pagupta@redhat.com, Pavel Tatashin , Oscar Salvador Cc: linux-mm@kvack.org, kirill.shutemov@linux.intel.com, Baoquan He Subject: [PATCH v6 0/5] mm/sparse: Optimize memmap allocation during sparse_init() Date: Thu, 28 Jun 2018 14:28:52 +0800 Message-Id: <20180628062857.29658-1-bhe@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Thu, 28 Jun 2018 06:29:05 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Thu, 28 Jun 2018 06:29:05 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'bhe@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is v6 post. In sparse_init(), two temporary pointer arrays, usemap_map and map_map are allocated with the size of NR_MEM_SECTIONS. They are used to store each memory section's usemap and mem map if marked as present. In 5-level paging mode, this will cost 512M memory though they will be released at the end of sparse_init(). System with few memory, like kdump kernel which usually only has about 256M, will fail to boot because of allocation failure if CONFIG_X86_5LEVEL=y. In this patchset, optimize the memmap allocation code to only use usemap_map and map_map with the size of nr_present_sections. This makes kdump kernel boot up with normal crashkernel='' setting when CONFIG_X86_5LEVEL=y. The old version can be found below: v5: http://lkml.kernel.org/r/20180627013116.12411-1-bhe@redhat.com v4: http://lkml.kernel.org/r/20180521101555.25610-1-bhe@redhat.com v3: https://lkml.org/lkml/2018/2/27/928 V1 can be found here: https://www.spinics.net/lists/linux-mm/msg144486.html Change log: v5->v6: Oscar found the redundant "struct mem_section *ms" definition and in the old patch 2/4, after deferring the clearing of section_mem_map. Clean them up in this version. Pavel pointed out that allocating memmap together for one node at one time should be a default behaviour for all ARCH-es. And if failed on large memory, it will drop to the fallback to allocate memmap for one section at one time, it shoult not break anything. Add patch 5/5 to remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER and clean up the related codes. v4->v5: Improve patch 3/4 log according to Dave's suggestion. Correct the wrong copy&paste of making 'nr_consumed_maps' to 'alloc_usemap_and_memmap' mistakenly which is pointed out by Dave in patch 4/4 code comment. Otherwise, no code change in this version. v3->v4: Improve according to Dave's three concerns which are in patch 0004: Rename variable 'idx_present' to 'nr_consumed_maps' which used to index the memmap and usemap of present sections. Add a check if 'nr_consumed_maps' goes beyond nr_present_sections. Add code comment above the final for_each_present_section_nr() to tell why 'nr_consumed_maps' need be increased in each iteration whether the 'ms->section_mem_map' need cleared or out. v2->v3: Change nr_present_sections as __initdata and add code comment according to Andrew's suggestion. Change the local variable 'i' as idx_present which loops over the present sections, and improve the code. These are suggested by Dave and Pankaj. Add a new patch 0003 which adds a new parameter 'data_unit_size' to function alloc_usemap_and_memmap() in which we will update 'data' to make it point at new position. However its type 'void *' can't give us needed info to do that. Need pass the unit size in. So change code in patch 0004 accordingly. This is a code bug fix found when tested the memory deployed on multiple nodes. v1-v2: Split out the nr_present_sections adding as a single patch for easier reviewing. Rewrite patch log according to Dave's suggestion. Fix code bug in patch 0002 reported by test robot. Baoquan He (5): mm/sparse: Add a static variable nr_present_sections mm/sparsemem: Defer the ms->section_mem_map clearing mm/sparse: Add a new parameter 'data_unit_size' for alloc_usemap_and_memmap mm/sparse: Optimize memmap allocation during sparse_init() mm/sparse: Remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER mm/Kconfig | 4 -- mm/sparse-vmemmap.c | 9 ++--- mm/sparse.c | 109 ++++++++++++++++++++++++++++------------------------ 3 files changed, 62 insertions(+), 60 deletions(-) -- 2.13.6