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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 E6D02C34031 for ; Thu, 20 Feb 2020 06:16:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C515B2465D for ; Thu, 20 Feb 2020 06:16:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726771AbgBTGQs (ORCPT ); Thu, 20 Feb 2020 01:16:48 -0500 Received: from mga01.intel.com ([192.55.52.88]:22133 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726027AbgBTGQs (ORCPT ); Thu, 20 Feb 2020 01:16:48 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Feb 2020 22:16:47 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,463,1574150400"; d="scan'208";a="436484979" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga006.fm.intel.com with ESMTP; 19 Feb 2020 22:16:44 -0800 Date: Thu, 20 Feb 2020 14:17:04 +0800 From: Wei Yang To: Baoquan He Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, richardw.yang@linux.intel.com, david@redhat.com, osalvador@suse.de, dan.j.williams@intel.com, mhocko@suse.com, rppt@linux.ibm.com, robin.murphy@arm.com Subject: Re: [PATCH v2 4/7] mm/sparse.c: only use subsection map in VMEMMAP case Message-ID: <20200220061704.GD32521@richard> Reply-To: Wei Yang References: <20200220043316.19668-1-bhe@redhat.com> <20200220043316.19668-5-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200220043316.19668-5-bhe@redhat.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 20, 2020 at 12:33:13PM +0800, Baoquan He wrote: >Currently, subsection map is used when SPARSEMEM is enabled, including >VMEMMAP case and !VMEMMAP case. However, subsection hotplug is not >supported at all in SPARSEMEM|!VMEMMAP case, subsection map is unnecessary >and misleading. Let's adjust code to only allow subsection map being >used in VMEMMAP case. > >Signed-off-by: Baoquan He Reviewed-by: Wei Yang >--- > include/linux/mmzone.h | 2 ++ > mm/sparse.c | 20 ++++++++++++++++++++ > 2 files changed, 22 insertions(+) > >diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h >index 462f6873905a..fc0de3a9a51e 100644 >--- a/include/linux/mmzone.h >+++ b/include/linux/mmzone.h >@@ -1185,7 +1185,9 @@ static inline unsigned long section_nr_to_pfn(unsigned long sec) > #define SUBSECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SUBSECTION_MASK) > > struct mem_section_usage { >+#ifdef CONFIG_SPARSEMEM_VMEMMAP > DECLARE_BITMAP(subsection_map, SUBSECTIONS_PER_SECTION); >+#endif > /* See declaration of similar field in struct zone */ > unsigned long pageblock_flags[0]; > }; >diff --git a/mm/sparse.c b/mm/sparse.c >index df857ee9330c..66c497d6a229 100644 >--- a/mm/sparse.c >+++ b/mm/sparse.c >@@ -209,6 +209,7 @@ static inline unsigned long first_present_section_nr(void) > return next_present_section_nr(-1); > } > >+#ifdef CONFIG_SPARSEMEM_VMEMMAP > static void subsection_mask_set(unsigned long *map, unsigned long pfn, > unsigned long nr_pages) > { >@@ -243,6 +244,11 @@ void __init subsection_map_init(unsigned long pfn, unsigned long nr_pages) > nr_pages -= pfns; > } > } >+#else >+void __init subsection_map_init(unsigned long pfn, unsigned long nr_pages) >+{ >+} >+#endif > > /* Record a memory area against a node. */ > void __init memory_present(int nid, unsigned long start, unsigned long end) >@@ -726,6 +732,7 @@ static void free_map_bootmem(struct page *memmap) > } > #endif /* CONFIG_SPARSEMEM_VMEMMAP */ > >+#ifdef CONFIG_SPARSEMEM_VMEMMAP > /** > * clear_subsection_map - Clear subsection map of one memory region > * >@@ -764,6 +771,12 @@ static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages) > > return 1; > } >+#else >+static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages) >+{ >+ return 0; >+} >+#endif > > static void section_deactivate(unsigned long pfn, unsigned long nr_pages, > struct vmem_altmap *altmap) >@@ -820,6 +833,7 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages, > ms->section_mem_map = (unsigned long)NULL; > } > >+#ifdef CONFIG_SPARSEMEM_VMEMMAP > /** > * fill_subsection_map - fill subsection map of a memory region > * @pfn - start pfn of the memory range >@@ -854,6 +868,12 @@ static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages) > > return rc; > } >+#else >+static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages) >+{ >+ return 0; >+} >+#endif > > static struct page * __meminit section_activate(int nid, unsigned long pfn, > unsigned long nr_pages, struct vmem_altmap *altmap) >-- >2.17.2 -- Wei Yang Help you, Help me