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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 B9D18C4360F for ; Thu, 4 Apr 2019 13:18:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 830112075E for ; Thu, 4 Apr 2019 13:18:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729400AbfDDNSE (ORCPT ); Thu, 4 Apr 2019 09:18:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33532 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726790AbfDDNSE (ORCPT ); Thu, 4 Apr 2019 09:18:04 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 64F84306D338; Thu, 4 Apr 2019 13:18:03 +0000 (UTC) Received: from [10.36.117.116] (ovpn-117-116.ams2.redhat.com [10.36.117.116]) by smtp.corp.redhat.com (Postfix) with ESMTP id 360B26C77F; Thu, 4 Apr 2019 13:18:01 +0000 (UTC) Subject: Re: [PATCH 1/2] mm, memory_hotplug: cleanup memory offline path To: Oscar Salvador , akpm@linux-foundation.org Cc: mhocko@suse.com, dan.j.williams@intel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20190404125916.10215-1-osalvador@suse.de> <20190404125916.10215-2-osalvador@suse.de> From: David Hildenbrand Openpgp: preference=signencrypt Autocrypt: addr=david@redhat.com; prefer-encrypt=mutual; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwX4EEwECACgFAljj9eoCGwMFCQlmAYAGCwkI BwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEE3eEPcA/4Na5IIP/3T/FIQMxIfNzZshIq687qgG 8UbspuE/YSUDdv7r5szYTK6KPTlqN8NAcSfheywbuYD9A4ZeSBWD3/NAVUdrCaRP2IvFyELj xoMvfJccbq45BxzgEspg/bVahNbyuBpLBVjVWwRtFCUEXkyazksSv8pdTMAs9IucChvFmmq3 jJ2vlaz9lYt/lxN246fIVceckPMiUveimngvXZw21VOAhfQ+/sofXF8JCFv2mFcBDoa7eYob s0FLpmqFaeNRHAlzMWgSsP80qx5nWWEvRLdKWi533N2vC/EyunN3HcBwVrXH4hxRBMco3jvM m8VKLKao9wKj82qSivUnkPIwsAGNPdFoPbgghCQiBjBe6A75Z2xHFrzo7t1jg7nQfIyNC7ez MZBJ59sqA9EDMEJPlLNIeJmqslXPjmMFnE7Mby/+335WJYDulsRybN+W5rLT5aMvhC6x6POK z55fMNKrMASCzBJum2Fwjf/VnuGRYkhKCqqZ8gJ3OvmR50tInDV2jZ1DQgc3i550T5JDpToh dPBxZocIhzg+MBSRDXcJmHOx/7nQm3iQ6iLuwmXsRC6f5FbFefk9EjuTKcLMvBsEx+2DEx0E UnmJ4hVg7u1PQ+2Oy+Lh/opK/BDiqlQ8Pz2jiXv5xkECvr/3Sv59hlOCZMOaiLTTjtOIU7Tq 7ut6OL64oAq+zsFNBFXLn5EBEADn1959INH2cwYJv0tsxf5MUCghCj/CA/lc/LMthqQ773ga uB9mN+F1rE9cyyXb6jyOGn+GUjMbnq1o121Vm0+neKHUCBtHyseBfDXHA6m4B3mUTWo13nid 0e4AM71r0DS8+KYh6zvweLX/LL5kQS9GQeT+QNroXcC1NzWbitts6TZ+IrPOwT1hfB4WNC+X 2n4AzDqp3+ILiVST2DT4VBc11Gz6jijpC/KI5Al8ZDhRwG47LUiuQmt3yqrmN63V9wzaPhC+ xbwIsNZlLUvuRnmBPkTJwwrFRZvwu5GPHNndBjVpAfaSTOfppyKBTccu2AXJXWAE1Xjh6GOC 8mlFjZwLxWFqdPHR1n2aPVgoiTLk34LR/bXO+e0GpzFXT7enwyvFFFyAS0Nk1q/7EChPcbRb hJqEBpRNZemxmg55zC3GLvgLKd5A09MOM2BrMea+l0FUR+PuTenh2YmnmLRTro6eZ/qYwWkC u8FFIw4pT0OUDMyLgi+GI1aMpVogTZJ70FgV0pUAlpmrzk/bLbRkF3TwgucpyPtcpmQtTkWS gDS50QG9DR/1As3LLLcNkwJBZzBG6PWbvcOyrwMQUF1nl4SSPV0LLH63+BrrHasfJzxKXzqg rW28CTAE2x8qi7e/6M/+XXhrsMYG+uaViM7n2je3qKe7ofum3s4vq7oFCPsOgwARAQABwsFl BBgBAgAPBQJVy5+RAhsMBQkJZgGAAAoJEE3eEPcA/4NagOsP/jPoIBb/iXVbM+fmSHOjEshl KMwEl/m5iLj3iHnHPVLBUWrXPdS7iQijJA/VLxjnFknhaS60hkUNWexDMxVVP/6lbOrs4bDZ NEWDMktAeqJaFtxackPszlcpRVkAs6Msn9tu8hlvB517pyUgvuD7ZS9gGOMmYwFQDyytpepo YApVV00P0u3AaE0Cj/o71STqGJKZxcVhPaZ+LR+UCBZOyKfEyq+ZN311VpOJZ1IvTExf+S/5 lqnciDtbO3I4Wq0ArLX1gs1q1XlXLaVaA3yVqeC8E7kOchDNinD3hJS4OX0e1gdsx/e6COvy qNg5aL5n0Kl4fcVqM0LdIhsubVs4eiNCa5XMSYpXmVi3HAuFyg9dN+x8thSwI836FoMASwOl C7tHsTjnSGufB+D7F7ZBT61BffNBBIm1KdMxcxqLUVXpBQHHlGkbwI+3Ye+nE6HmZH7IwLwV W+Ajl7oYF+jeKaH4DZFtgLYGLtZ1LDwKPjX7VAsa4Yx7S5+EBAaZGxK510MjIx6SGrZWBrrV TEvdV00F2MnQoeXKzD7O4WFbL55hhyGgfWTHwZ457iN9SgYi1JLPqWkZB0JRXIEtjd4JEQcx +8Umfre0Xt4713VxMygW0PnQt5aSQdMD58jHFxTk092mU+yIHj5LeYgvwSgZN4airXk5yRXl SE+xAvmumFBY Organization: Red Hat GmbH Message-ID: Date: Thu, 4 Apr 2019 15:18:00 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190404125916.10215-2-osalvador@suse.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Thu, 04 Apr 2019 13:18:03 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04.04.19 14:59, Oscar Salvador wrote: > From: Michal Hocko > > check_pages_isolated_cb currently accounts the whole pfn range as being > offlined if test_pages_isolated suceeds on the range. This is based on > the assumption that all pages in the range are freed which is currently > the case in most cases but it won't be with later changes, as pages > marked as vmemmap won't be isolated. > > Move the offlined pages counting to offline_isolated_pages_cb and > rely on __offline_isolated_pages to return the correct value. > check_pages_isolated_cb will still do it's primary job and check the pfn > range. > > While we are at it remove check_pages_isolated and offline_isolated_pages > and use directly walk_system_ram_range as do in online_pages. > > Signed-off-by: Michal Hocko > Signed-off-by: Oscar Salvador > --- > include/linux/memory_hotplug.h | 3 ++- > mm/memory_hotplug.c | 46 +++++++++++------------------------------- > mm/page_alloc.c | 11 ++++++++-- > 3 files changed, 23 insertions(+), 37 deletions(-) > > diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h > index 8ade08c50d26..3c8cf347804c 100644 > --- a/include/linux/memory_hotplug.h > +++ b/include/linux/memory_hotplug.h > @@ -87,7 +87,8 @@ extern int add_one_highpage(struct page *page, int pfn, int bad_ppro); > extern int online_pages(unsigned long, unsigned long, int); > extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn, > unsigned long *valid_start, unsigned long *valid_end); > -extern void __offline_isolated_pages(unsigned long, unsigned long); > +extern unsigned long __offline_isolated_pages(unsigned long start_pfn, > + unsigned long end_pfn); > > typedef void (*online_page_callback_t)(struct page *page, unsigned int order); > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index f206b8b66af1..d8a3e9554aec 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1451,15 +1451,11 @@ static int > offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages, > void *data) > { > - __offline_isolated_pages(start, start + nr_pages); > - return 0; > -} > + unsigned long offlined_pages; > > -static void > -offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) > -{ > - walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL, > - offline_isolated_pages_cb); > + offlined_pages = __offline_isolated_pages(start, start + nr_pages); > + *(unsigned long *)data += offlined_pages; unsigned long *offlined_pages = data; *offlined_pages += __offline_isolated_pages(start, start + nr_pages); > + return 0; > } > > /* > @@ -1469,26 +1465,7 @@ static int > check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages, > void *data) > { > - int ret; > - long offlined = *(long *)data; > - ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true); > - offlined = nr_pages; > - if (!ret) > - *(long *)data += offlined; > - return ret; > -} > - > -static long > -check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn) > -{ > - long offlined = 0; > - int ret; > - > - ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined, > - check_pages_isolated_cb); > - if (ret < 0) > - offlined = (long)ret; > - return offlined; > + return test_pages_isolated(start_pfn, start_pfn + nr_pages, true); > } > > static int __init cmdline_parse_movable_node(char *p) > @@ -1573,7 +1550,7 @@ static int __ref __offline_pages(unsigned long start_pfn, > unsigned long end_pfn) > { > unsigned long pfn, nr_pages; > - long offlined_pages; > + unsigned long offlined_pages = 0; > int ret, node, nr_isolate_pageblock; > unsigned long flags; > unsigned long valid_start, valid_end; > @@ -1649,14 +1626,15 @@ static int __ref __offline_pages(unsigned long start_pfn, > goto failed_removal_isolated; > } > /* check again */ > - offlined_pages = check_pages_isolated(start_pfn, end_pfn); > - } while (offlined_pages < 0); > + ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL, > + check_pages_isolated_cb); indentation looks strange, but might be my mail client. > + } while (ret); > > - pr_info("Offlined Pages %ld\n", offlined_pages); > /* Ok, all of our target is isolated. > We cannot do rollback at this point. */ > - offline_isolated_pages(start_pfn, end_pfn); > - > + walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined_pages, > + offline_isolated_pages_cb); dito > + pr_info("Offlined Pages %ld\n", offlined_pages); > /* > * Onlining will reset pagetype flags and makes migrate type > * MOVABLE, so just need to decrease the number of isolated > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 0c53807a2943..d36ca67064c9 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -8375,7 +8375,7 @@ void zone_pcp_reset(struct zone *zone) > * All pages in the range must be in a single zone and isolated > * before calling this. > */ > -void > +unsigned long > __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) > { > struct page *page; > @@ -8383,12 +8383,15 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) > unsigned int order, i; > unsigned long pfn; > unsigned long flags; > + unsigned long offlined_pages = 0; > + > /* find the first valid pfn */ > for (pfn = start_pfn; pfn < end_pfn; pfn++) > if (pfn_valid(pfn)) > break; > if (pfn == end_pfn) > - return; > + return offlined_pages; > + > offline_mem_sections(pfn, end_pfn); > zone = page_zone(pfn_to_page(pfn)); > spin_lock_irqsave(&zone->lock, flags); > @@ -8406,12 +8409,14 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) > if (unlikely(!PageBuddy(page) && PageHWPoison(page))) { > pfn++; > SetPageReserved(page); > + offlined_pages++; > continue; > } > > BUG_ON(page_count(page)); > BUG_ON(!PageBuddy(page)); > order = page_order(page); > + offlined_pages += 1 << order; > #ifdef CONFIG_DEBUG_VM > pr_info("remove from free list %lx %d %lx\n", > pfn, 1 << order, end_pfn); > @@ -8422,6 +8427,8 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) > pfn += (1 << order); > } > spin_unlock_irqrestore(&zone->lock, flags); > + > + return offlined_pages; > } > #endif > > Only nits Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb