From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f198.google.com (mail-io0-f198.google.com [209.85.223.198]) by kanga.kvack.org (Postfix) with ESMTP id B2F306B0007 for ; Wed, 27 Jun 2018 23:12:14 -0400 (EDT) Received: by mail-io0-f198.google.com with SMTP id s19-v6so3231902iog.0 for ; Wed, 27 Jun 2018 20:12:14 -0700 (PDT) Received: from aserp2120.oracle.com (aserp2120.oracle.com. [141.146.126.78]) by mx.google.com with ESMTPS id r103-v6si3975412ioi.273.2018.06.27.20.12.13 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 Jun 2018 20:12:13 -0700 (PDT) Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w5S38hQe120081 for ; Thu, 28 Jun 2018 03:12:13 GMT Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by aserp2120.oracle.com with ESMTP id 2jukhsfqw3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Thu, 28 Jun 2018 03:12:13 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w5S3CCLI010754 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Thu, 28 Jun 2018 03:12:12 GMT Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w5S3CBQH015145 for ; Thu, 28 Jun 2018 03:12:12 GMT Received: by mail-oi0-f45.google.com with SMTP id k81-v6so3814400oib.4 for ; Wed, 27 Jun 2018 20:12:11 -0700 (PDT) MIME-Version: 1.0 References: <20180627013116.12411-1-bhe@redhat.com> <20180627013116.12411-3-bhe@redhat.com> <20180627095439.GA5924@techadventures.net> <20180627225945.GD8970@localhost.localdomain> In-Reply-To: <20180627225945.GD8970@localhost.localdomain> From: Pavel Tatashin Date: Wed, 27 Jun 2018 23:11:35 -0400 Message-ID: Subject: Re: [PATCH v5 2/4] mm/sparsemem: Defer the ms->section_mem_map clearing Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: bhe@redhat.com Cc: osalvador@techadventures.net, LKML , Andrew Morton , dave.hansen@intel.com, pagupta@redhat.com, Linux Memory Management List , kirill.shutemov@linux.intel.com Once you remove the ms mentioned by Oscar: Reviewed-by: Pavel Tatashin On Wed, Jun 27, 2018 at 6:59 PM Baoquan He wrote: > > On 06/27/18 at 11:54am, Oscar Salvador wrote: > > On Wed, Jun 27, 2018 at 09:31:14AM +0800, Baoquan He wrote: > > > In sparse_init(), if CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER=y, system > > > will allocate one continuous memory chunk for mem maps on one node and > > > populate the relevant page tables to map memory section one by one. If > > > fail to populate for a certain mem section, print warning and its > > > ->section_mem_map will be cleared to cancel the marking of being present. > > > Like this, the number of mem sections marked as present could become > > > less during sparse_init() execution. > > > > > > Here just defer the ms->section_mem_map clearing if failed to populate > > > its page tables until the last for_each_present_section_nr() loop. This > > > is in preparation for later optimizing the mem map allocation. > > > > > > Signed-off-by: Baoquan He > > > --- > > > mm/sparse-vmemmap.c | 1 - > > > mm/sparse.c | 12 ++++++++---- > > > 2 files changed, 8 insertions(+), 5 deletions(-) > > > > > > diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c > > > index bd0276d5f66b..640e68f8324b 100644 > > > --- a/mm/sparse-vmemmap.c > > > +++ b/mm/sparse-vmemmap.c > > > @@ -303,7 +303,6 @@ void __init sparse_mem_maps_populate_node(struct page **map_map, > > > ms = __nr_to_section(pnum); > > > pr_err("%s: sparsemem memory map backing failed some memory will not be available\n", > > > __func__); > > > - ms->section_mem_map = 0; > > > > Since we are deferring the clearing of section_mem_map, I guess we do not need > > > > struct mem_section *ms; > > ms = __nr_to_section(pnum); > > > > anymore, right? > > Right, good catch, thanks. > > I will post a new round to fix this. > > > > > > } > > > > > > if (vmemmap_buf_start) { > > > diff --git a/mm/sparse.c b/mm/sparse.c > > > index 6314303130b0..71ad53da2cd1 100644 > > > --- a/mm/sparse.c > > > +++ b/mm/sparse.c > > > @@ -451,7 +451,6 @@ void __init sparse_mem_maps_populate_node(struct page **map_map, > > > ms = __nr_to_section(pnum); > > > pr_err("%s: sparsemem memory map backing failed some memory will not be available\n", > > > __func__); > > > - ms->section_mem_map = 0; > > > > The same goes here. > > > > > > > > -- > > Oscar Salvador > > SUSE L3 >