From patchwork Mon Dec 9 17:48:36 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11279779 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 6445F1575 for ; Mon, 9 Dec 2019 17:48:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1C22420836 for ; Mon, 9 Dec 2019 17:48:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="V+fWroDq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1C22420836 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 82DD26B27EA; Mon, 9 Dec 2019 12:48:54 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 7B6D76B27E9; Mon, 9 Dec 2019 12:48:54 -0500 (EST) 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 5C7A06B27E9; Mon, 9 Dec 2019 12:48:54 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0163.hostedemail.com [216.40.44.163]) by kanga.kvack.org (Postfix) with ESMTP id 424366B27E9 for ; Mon, 9 Dec 2019 12:48:54 -0500 (EST) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id E050A8249980 for ; Mon, 9 Dec 2019 17:48:53 +0000 (UTC) X-FDA: 76246338546.15.lead18_6abc5aacf3059 X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,david@redhat.com,:linux-kernel@vger.kernel.org::david@redhat.com:akpm@linux-foundation.org:osalvador@suse.de:mhocko@kernel.org:dan.j.williams@intel.com:n-horiguchi@ah.jp.nec.com,RULES_HIT:30003:30034:30045:30054:30064:30070:30090,0,RBL:207.211.31.120:@redhat.com:.lbl8.mailshell.net-62.18.0.100 66.10.201.10,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: lead18_6abc5aacf3059 X-Filterd-Recvd-Size: 9365 Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by imf19.hostedemail.com (Postfix) with ESMTP for ; Mon, 9 Dec 2019 17:48:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1575913732; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JIMYiSqspAv8n61S8tgbkZ68HfWcOMbw8/ayJuQpZ20=; b=V+fWroDq7ImftUmpnRueGkPTEGxSG4J5m/u1oceKMLdCpNnpbdnxDQtJNdMW1EZNXdgX3H pCtnZKxaotIeHdFFKjbmkDzk1bjLHRE3XyEn9M3nOxcv5cK4u0Uxa+vE9rw/XdMdnaBTtu s4x/Vc2ML43qwR0fw+gl1wfG8zaZbhs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-195-J57-AI3yNo22k9uftEx15w-1; Mon, 09 Dec 2019 12:48:51 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1B6B6801E77; Mon, 9 Dec 2019 17:48:50 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-214.ams2.redhat.com [10.36.116.214]) by smtp.corp.redhat.com (Postfix) with ESMTP id 580941001938; Mon, 9 Dec 2019 17:48:48 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Dan Williams , Naoya Horiguchi Subject: [PATCH v1 3/3] mm: initialize memmap of unavailable memory directly Date: Mon, 9 Dec 2019 18:48:36 +0100 Message-Id: <20191209174836.11063-4-david@redhat.com> In-Reply-To: <20191209174836.11063-1-david@redhat.com> References: <20191209174836.11063-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-MC-Unique: J57-AI3yNo22k9uftEx15w-1 X-Mimecast-Spam-Score: 0 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: Let's make sure that all memory holes are actually marked PageReserved(), that page_to_pfn() produces reliable results, and that these pages are not detected as "mmap" pages due to the mapcount. E.g., booting a x86-64 QEMU guest with 4160 MB: [ 0.010585] Early memory node ranges [ 0.010586] node 0: [mem 0x0000000000001000-0x000000000009efff] [ 0.010588] node 0: [mem 0x0000000000100000-0x00000000bffdefff] [ 0.010589] node 0: [mem 0x0000000100000000-0x0000000143ffffff] max_pfn is 0x144000. Before this change: [root@localhost ~]# ./page-types -r -a 0x144000, flags page-count MB symbolic-flags long-symbolic-flags 0x0000000000000800 16384 64 ___________M_______________________________ mmap total 16384 64 After this change: [root@localhost ~]# ./page-types -r -a 0x144000, flags page-count MB symbolic-flags long-symbolic-flags 0x0000000100000000 16384 64 ___________________________r_______________ reserved total 16384 64 IOW, especially the unavailable physical memory ("memory hole") in the last section would not get properly marked PageReserved() and is indicated to be "mmap" memory. Drop the trace of that function from include/linux/mm.h - nobody else needs it, and rename it accordingly. Note: The fake zone/node might not be covered by the zone/node span. This is not an urgent issue (for now, we had the same node/zone due to the zeroing). We'll need a clean way to mark memory holes (e.g., using a page type PageHole() if possible or a fake ZONE_INVALID) and eventually stop marking these memory holes PageReserved(). Cc: Andrew Morton Cc: Oscar Salvador Cc: Michal Hocko Cc: Dan Williams Cc: Naoya Horiguchi Signed-off-by: David Hildenbrand --- include/linux/mm.h | 6 ------ mm/page_alloc.c | 33 ++++++++++++++++++++++----------- 2 files changed, 22 insertions(+), 17 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5dfbc0e56e67..93ee776c2a1e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2176,12 +2176,6 @@ extern int __meminit __early_pfn_to_nid(unsigned long pfn, struct mminit_pfnnid_cache *state); #endif -#if !defined(CONFIG_FLAT_NODE_MEM_MAP) -void zero_resv_unavail(void); -#else -static inline void zero_resv_unavail(void) {} -#endif - extern void set_dma_reserve(unsigned long new_dma_reserve); extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long, enum memmap_context, struct vmem_altmap *); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1eb2ce7c79e4..85064abafcc3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6901,10 +6901,10 @@ void __init free_area_init_node(int nid, unsigned long *zones_size, #if !defined(CONFIG_FLAT_NODE_MEM_MAP) /* - * Zero all valid struct pages in range [spfn, epfn), return number of struct - * pages zeroed + * Initialize all valid struct pages in the range [spfn, epfn) and mark them + * PageReserved(). Return the number of struct pages that were initialized. */ -static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn) +static u64 __init init_unavailable_range(unsigned long spfn, unsigned long epfn) { unsigned long pfn; u64 pgcnt = 0; @@ -6915,7 +6915,13 @@ static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn) + pageblock_nr_pages - 1; continue; } - mm_zero_struct_page(pfn_to_page(pfn)); + /* + * Use a fake node/zone (0) for now. Some of these pages + * (in memblock.reserved but not in memblock.memory) will + * get re-initialized via reserve_bootmem_region() later. + */ + __init_single_page(pfn_to_page(pfn), pfn, 0, 0); + __SetPageReserved(pfn_to_page(pfn)); pgcnt++; } @@ -6927,7 +6933,7 @@ static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn) * initialized by going through __init_single_page(). But, there are some * struct pages which are reserved in memblock allocator and their fields * may be accessed (for example page_to_pfn() on some configuration accesses - * flags). We must explicitly zero those struct pages. + * flags). We must explicitly initialize those struct pages. * * This function also addresses a similar issue where struct pages are left * uninitialized because the physical address range is not covered by @@ -6935,7 +6941,7 @@ static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn) * layout is manually configured via memmap=, or when the highest physical * address (max_pfn) does not end on a section boundary. */ -void __init zero_resv_unavail(void) +static void __init init_unavailable_mem(void) { phys_addr_t start, end; u64 i, pgcnt; @@ -6948,7 +6954,8 @@ void __init zero_resv_unavail(void) for_each_mem_range(i, &memblock.memory, NULL, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end, NULL) { if (next < start) - pgcnt += zero_pfn_range(PFN_DOWN(next), PFN_UP(start)); + pgcnt += init_unavailable_range(PFN_DOWN(next), + PFN_UP(start)); next = end; } @@ -6959,8 +6966,8 @@ void __init zero_resv_unavail(void) * considered initialized. Make sure that memmap has a well defined * state. */ - pgcnt += zero_pfn_range(PFN_DOWN(next), - round_up(max_pfn, PAGES_PER_SECTION)); + pgcnt += init_unavailable_range(PFN_DOWN(next), + round_up(max_pfn, PAGES_PER_SECTION)); /* * Struct pages that do not have backing memory. This could be because @@ -6969,6 +6976,10 @@ void __init zero_resv_unavail(void) if (pgcnt) pr_info("Zeroed struct page in unavailable ranges: %lld pages", pgcnt); } +#else +static inline void __init init_unavailable_mem(void) +{ +} #endif /* !CONFIG_FLAT_NODE_MEM_MAP */ #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP @@ -7398,7 +7409,7 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn) /* Initialise every node */ mminit_verify_pageflags_layout(); setup_nr_node_ids(); - zero_resv_unavail(); + init_unavailable_mem(); for_each_online_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); free_area_init_node(nid, NULL, @@ -7593,7 +7604,7 @@ void __init set_dma_reserve(unsigned long new_dma_reserve) void __init free_area_init(unsigned long *zones_size) { - zero_resv_unavail(); + init_unavailable_mem(); free_area_init_node(0, zones_size, __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL); }