From patchwork Sun Oct 6 08:56:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176003 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 360961709 for ; Sun, 6 Oct 2019 08:57:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 128D62084B for ; Sun, 6 Oct 2019 08:57:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726210AbfJFI5F (ORCPT ); Sun, 6 Oct 2019 04:57:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46420 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5F (ORCPT ); Sun, 6 Oct 2019 04:57:05 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D1E313082A6C; Sun, 6 Oct 2019 08:57:04 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id 090595B681; Sun, 6 Oct 2019 08:57:01 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, "Aneesh Kumar K.V" , Dan Williams , Andrew Morton , Jason Gunthorpe , Logan Gunthorpe , Ira Weiny , David Hildenbrand Subject: [PATCH v6 01/10] mm/memunmap: Don't access uninitialized memmap in memunmap_pages() Date: Sun, 6 Oct 2019 10:56:37 +0200 Message-Id: <20191006085646.5768-2-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Sun, 06 Oct 2019 08:57:05 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org From: "Aneesh Kumar K.V" With an altmap, the memmap falling into the reserved altmap space are not initialized and, therefore, contain a garbage NID and a garbage zone. Make sure to read the NID/zone from a memmap that was initialzed. This fixes a kernel crash that is observed when destroying a namespace: [ 81.356173] kernel BUG at include/linux/mm.h:1107! cpu 0x1: Vector: 700 (Program Check) at [c000000274087890] pc: c0000000004b9728: memunmap_pages+0x238/0x340 lr: c0000000004b9724: memunmap_pages+0x234/0x340 ... pid = 3669, comm = ndctl kernel BUG at include/linux/mm.h:1107! [c000000274087ba0] c0000000009e3500 devm_action_release+0x30/0x50 [c000000274087bc0] c0000000009e4758 release_nodes+0x268/0x2d0 [c000000274087c30] c0000000009dd144 device_release_driver_internal+0x174/0x240 [c000000274087c70] c0000000009d9dfc unbind_store+0x13c/0x190 [c000000274087cb0] c0000000009d8a24 drv_attr_store+0x44/0x60 [c000000274087cd0] c0000000005a7470 sysfs_kf_write+0x70/0xa0 [c000000274087d10] c0000000005a5cac kernfs_fop_write+0x1ac/0x290 [c000000274087d60] c0000000004be45c __vfs_write+0x3c/0x70 [c000000274087d80] c0000000004c26e4 vfs_write+0xe4/0x200 [c000000274087dd0] c0000000004c2a6c ksys_write+0x7c/0x140 [c000000274087e20] c00000000000bbd0 system_call+0x5c/0x68 Cc: Dan Williams Cc: Andrew Morton Cc: Jason Gunthorpe Cc: Logan Gunthorpe Cc: Ira Weiny Signed-off-by: Aneesh Kumar K.V [ minimze code changes, rephrase description ] Signed-off-by: David Hildenbrand --- mm/memremap.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/mm/memremap.c b/mm/memremap.c index 557e53c6fb46..8c2fb44c3b4d 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -123,6 +123,7 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) void memunmap_pages(struct dev_pagemap *pgmap) { struct resource *res = &pgmap->res; + struct page *first_page; unsigned long pfn; int nid; @@ -131,14 +132,16 @@ void memunmap_pages(struct dev_pagemap *pgmap) put_page(pfn_to_page(pfn)); dev_pagemap_cleanup(pgmap); + /* make sure to access a memmap that was actually initialized */ + first_page = pfn_to_page(pfn_first(pgmap)); + /* pages are dead and unused, undo the arch mapping */ - nid = page_to_nid(pfn_to_page(PHYS_PFN(res->start))); + nid = page_to_nid(first_page); mem_hotplug_begin(); if (pgmap->type == MEMORY_DEVICE_PRIVATE) { - pfn = PHYS_PFN(res->start); - __remove_pages(page_zone(pfn_to_page(pfn)), pfn, - PHYS_PFN(resource_size(res)), NULL); + __remove_pages(page_zone(first_page), PHYS_PFN(res->start), + PHYS_PFN(resource_size(res)), NULL); } else { arch_remove_memory(nid, res->start, resource_size(res), pgmap_altmap(pgmap)); From patchwork Sun Oct 6 08:56:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176011 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 D322E1709 for ; Sun, 6 Oct 2019 08:57:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BA6412084B for ; Sun, 6 Oct 2019 08:57:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726365AbfJFI5M (ORCPT ); Sun, 6 Oct 2019 04:57:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40112 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5M (ORCPT ); Sun, 6 Oct 2019 04:57:12 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6FE6985539; Sun, 6 Oct 2019 08:57:11 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2E0BB5D772; Sun, 6 Oct 2019 08:57:05 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, "Aneesh Kumar K.V" , Andrew Morton , Michal Hocko , Vlastimil Babka , Oscar Salvador , Mel Gorman , Mike Rapoport , Dan Williams , Alexander Duyck , Pavel Tatashin , Alexander Potapenko , Pankaj Gupta , David Hildenbrand Subject: [PATCH v6 02/10] mm/memmap_init: Update variable name in memmap_init_zone Date: Sun, 6 Oct 2019 10:56:38 +0200 Message-Id: <20191006085646.5768-3-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Sun, 06 Oct 2019 08:57:11 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org From: "Aneesh Kumar K.V" The third argument is actually number of pages. Changes the variable name from size to nr_pages to indicate this better. No functional change in this patch. Cc: Andrew Morton Cc: Michal Hocko Cc: Vlastimil Babka Cc: Oscar Salvador Cc: Mel Gorman Cc: Mike Rapoport Cc: Dan Williams Cc: Alexander Duyck Cc: Pavel Tatashin Cc: Alexander Potapenko Reviewed-by: Pankaj Gupta Reviewed-by: David Hildenbrand Signed-off-by: Aneesh Kumar K.V Signed-off-by: David Hildenbrand --- mm/page_alloc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 15c2050c629b..b0b2d5464000 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5936,10 +5936,10 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, #ifdef CONFIG_ZONE_DEVICE void __ref memmap_init_zone_device(struct zone *zone, unsigned long start_pfn, - unsigned long size, + unsigned long nr_pages, struct dev_pagemap *pgmap) { - unsigned long pfn, end_pfn = start_pfn + size; + unsigned long pfn, end_pfn = start_pfn + nr_pages; struct pglist_data *pgdat = zone->zone_pgdat; struct vmem_altmap *altmap = pgmap_altmap(pgmap); unsigned long zone_idx = zone_idx(zone); @@ -5956,7 +5956,7 @@ void __ref memmap_init_zone_device(struct zone *zone, */ if (altmap) { start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); - size = end_pfn - start_pfn; + nr_pages = end_pfn - start_pfn; } for (pfn = start_pfn; pfn < end_pfn; pfn++) { @@ -6003,7 +6003,7 @@ void __ref memmap_init_zone_device(struct zone *zone, } pr_info("%s initialised %lu pages in %ums\n", __func__, - size, jiffies_to_msecs(jiffies - start)); + nr_pages, jiffies_to_msecs(jiffies - start)); } #endif From patchwork Sun Oct 6 08:56:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176017 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 405471709 for ; Sun, 6 Oct 2019 08:57:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F746214D9 for ; Sun, 6 Oct 2019 08:57:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726387AbfJFI5P (ORCPT ); Sun, 6 Oct 2019 04:57:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49136 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5P (ORCPT ); Sun, 6 Oct 2019 04:57:15 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BFDF5307D848; Sun, 6 Oct 2019 08:57:14 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id CE3EE5D772; Sun, 6 Oct 2019 08:57:11 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , Wei Yang , "Aneesh Kumar K . V" Subject: [PATCH v6 03/10] mm/memory_hotplug: Don't access uninitialized memmaps in shrink_pgdat_span() Date: Sun, 6 Oct 2019 10:56:39 +0200 Message-Id: <20191006085646.5768-4-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Sun, 06 Oct 2019 08:57:14 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org We might use the nid of memmaps that were never initialized. For example, if the memmap was poisoned, we will crash the kernel in pfn_to_nid() right now. Let's use the calculated boundaries of the separate zones instead. This now also avoids having to iterate over a whole bunch of subsections again, after shrinking one zone. Before commit d0dc12e86b31 ("mm/memory_hotplug: optimize memory hotplug"), the memmap was initialized to 0 and the node was set to the right value. After that commit, the node might be garbage. We'll have to fix shrink_zone_span() next. Cc: Andrew Morton Cc: Oscar Salvador Cc: David Hildenbrand Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Cc: Wei Yang Fixes: d0dc12e86b31 ("mm/memory_hotplug: optimize memory hotplug") Reported-by: Aneesh Kumar K.V Signed-off-by: David Hildenbrand --- mm/memory_hotplug.c | 72 ++++++++++----------------------------------- 1 file changed, 15 insertions(+), 57 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 680b4b3e57d9..86b4dc18e831 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -436,67 +436,25 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, zone_span_writeunlock(zone); } -static void shrink_pgdat_span(struct pglist_data *pgdat, - unsigned long start_pfn, unsigned long end_pfn) +static void update_pgdat_span(struct pglist_data *pgdat) { - unsigned long pgdat_start_pfn = pgdat->node_start_pfn; - unsigned long p = pgdat_end_pfn(pgdat); /* pgdat_end_pfn namespace clash */ - unsigned long pgdat_end_pfn = p; - unsigned long pfn; - int nid = pgdat->node_id; - - if (pgdat_start_pfn == start_pfn) { - /* - * If the section is smallest section in the pgdat, it need - * shrink pgdat->node_start_pfn and pgdat->node_spanned_pages. - * In this case, we find second smallest valid mem_section - * for shrinking zone. - */ - pfn = find_smallest_section_pfn(nid, NULL, end_pfn, - pgdat_end_pfn); - if (pfn) { - pgdat->node_start_pfn = pfn; - pgdat->node_spanned_pages = pgdat_end_pfn - pfn; - } - } else if (pgdat_end_pfn == end_pfn) { - /* - * If the section is biggest section in the pgdat, it need - * shrink pgdat->node_spanned_pages. - * In this case, we find second biggest valid mem_section for - * shrinking zone. - */ - pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn, - start_pfn); - if (pfn) - pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1; - } - - /* - * If the section is not biggest or smallest mem_section in the pgdat, - * it only creates a hole in the pgdat. So in this case, we need not - * change the pgdat. - * But perhaps, the pgdat has only hole data. Thus it check the pgdat - * has only hole or not. - */ - pfn = pgdat_start_pfn; - for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SUBSECTION) { - if (unlikely(!pfn_valid(pfn))) - continue; - - if (pfn_to_nid(pfn) != nid) - continue; + unsigned long node_start_pfn = 0, node_end_pfn = 0; + struct zone *zone; - /* Skip range to be removed */ - if (pfn >= start_pfn && pfn < end_pfn) - continue; + for (zone = pgdat->node_zones; + zone < pgdat->node_zones + MAX_NR_ZONES; zone++) { + unsigned long zone_end_pfn = zone->zone_start_pfn + + zone->spanned_pages; - /* If we find valid section, we have nothing to do */ - return; + /* No need to lock the zones, they can't change. */ + if (zone_end_pfn > node_end_pfn) + node_end_pfn = zone_end_pfn; + if (zone->zone_start_pfn < node_start_pfn) + node_start_pfn = zone->zone_start_pfn; } - /* The pgdat has no valid section */ - pgdat->node_start_pfn = 0; - pgdat->node_spanned_pages = 0; + pgdat->node_start_pfn = node_start_pfn; + pgdat->node_spanned_pages = node_end_pfn - node_start_pfn; } static void __remove_zone(struct zone *zone, unsigned long start_pfn, @@ -507,7 +465,7 @@ static void __remove_zone(struct zone *zone, unsigned long start_pfn, pgdat_resize_lock(zone->zone_pgdat, &flags); shrink_zone_span(zone, start_pfn, start_pfn + nr_pages); - shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages); + update_pgdat_span(pgdat); pgdat_resize_unlock(zone->zone_pgdat, &flags); } From patchwork Sun Oct 6 08:56:40 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176019 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 616151862 for ; Sun, 6 Oct 2019 08:57:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 49FCB214D9 for ; Sun, 6 Oct 2019 08:57:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726423AbfJFI5S (ORCPT ); Sun, 6 Oct 2019 04:57:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45774 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5S (ORCPT ); Sun, 6 Oct 2019 04:57:18 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D72C6A44ADD; Sun, 6 Oct 2019 08:57:17 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1B4E45B69A; Sun, 6 Oct 2019 08:57:14 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , "Aneesh Kumar K . V" Subject: [PATCH v6 04/10] mm/memory_hotplug: Don't access uninitialized memmaps in shrink_zone_span() Date: Sun, 6 Oct 2019 10:56:40 +0200 Message-Id: <20191006085646.5768-5-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.68]); Sun, 06 Oct 2019 08:57:18 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org Let's limit shrinking to !ZONE_DEVICE so we can fix the current code. We should never try to touch the memmap of offline sections where we could have uninitialized memmaps and could trigger BUGs when calling page_to_nid() on poisoned pages. There is no reliable way to distinguish an uninitialized memmap from an initialized memmap that belongs to ZONE_DEVICE, as we don't have anything like SECTION_IS_ONLINE we can use similar to pfn_to_online_section() for !ZONE_DEVICE memory. E.g., set_zone_contiguous() similarly relies on pfn_to_online_section() and will therefore never set a ZONE_DEVICE zone consecutive. Stopping to shrink the ZONE_DEVICE therefore results in no observable changes, besides /proc/zoneinfo indicating different boundaries - something we can totally live with. Before commit d0dc12e86b31 ("mm/memory_hotplug: optimize memory hotplug"), the memmap was initialized with 0 and the node with the right value. So the zone might be wrong but not garbage. After that commit, both the zone and the node will be garbage when touching uninitialized memmaps. Cc: Andrew Morton Cc: Oscar Salvador Cc: David Hildenbrand Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Fixes: d0dc12e86b31 ("mm/memory_hotplug: optimize memory hotplug") Reported-by: Aneesh Kumar K.V Signed-off-by: David Hildenbrand --- mm/memory_hotplug.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 86b4dc18e831..f96608d24f6a 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -331,7 +331,7 @@ static unsigned long find_smallest_section_pfn(int nid, struct zone *zone, unsigned long end_pfn) { for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SUBSECTION) { - if (unlikely(!pfn_valid(start_pfn))) + if (unlikely(!pfn_to_online_page(start_pfn))) continue; if (unlikely(pfn_to_nid(start_pfn) != nid)) @@ -356,7 +356,7 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone, /* pfn is the end pfn of a memory section. */ pfn = end_pfn - 1; for (; pfn >= start_pfn; pfn -= PAGES_PER_SUBSECTION) { - if (unlikely(!pfn_valid(pfn))) + if (unlikely(!pfn_to_online_page(pfn))) continue; if (unlikely(pfn_to_nid(pfn) != nid)) @@ -415,7 +415,7 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, */ pfn = zone_start_pfn; for (; pfn < zone_end_pfn; pfn += PAGES_PER_SUBSECTION) { - if (unlikely(!pfn_valid(pfn))) + if (unlikely(!pfn_to_online_page(pfn))) continue; if (page_zone(pfn_to_page(pfn)) != zone) @@ -463,6 +463,16 @@ static void __remove_zone(struct zone *zone, unsigned long start_pfn, struct pglist_data *pgdat = zone->zone_pgdat; unsigned long flags; +#ifdef CONFIG_ZONE_DEVICE + /* + * Zone shrinking code cannot properly deal with ZONE_DEVICE. So + * we will not try to shrink the zones - which is okay as + * set_zone_contiguous() cannot deal with ZONE_DEVICE either way. + */ + if (zone_idx(zone) == ZONE_DEVICE) + return; +#endif + pgdat_resize_lock(zone->zone_pgdat, &flags); shrink_zone_span(zone, start_pfn, start_pfn + nr_pages); update_pgdat_span(pgdat); From patchwork Sun Oct 6 08:56:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176027 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 315DC76 for ; Sun, 6 Oct 2019 08:57:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 188F12133F for ; Sun, 6 Oct 2019 08:57:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726368AbfJFI5d (ORCPT ); Sun, 6 Oct 2019 04:57:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51598 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5d (ORCPT ); Sun, 6 Oct 2019 04:57:33 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E1E0F806CD; Sun, 6 Oct 2019 08:57:32 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id C1AC65B681; Sun, 6 Oct 2019 08:57:27 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams Subject: [PATCH v6 06/10] mm/memory_hotplug: Poison memmap in remove_pfn_range_from_zone() Date: Sun, 6 Oct 2019 10:56:42 +0200 Message-Id: <20191006085646.5768-7-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Sun, 06 Oct 2019 08:57:33 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org Let's poison the pages similar to when adding new memory in sparse_add_section(). Also call remove_pfn_range_from_zone() from memunmap_pages(), so we can poison the memmap from there as well. While at it, calculate the pfn in memunmap_pages() only once. Cc: Andrew Morton Cc: David Hildenbrand Cc: Oscar Salvador Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador --- mm/memory_hotplug.c | 3 +++ mm/memremap.c | 2 ++ 2 files changed, 5 insertions(+) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 5b003ffa5dc9..bf5173e7913d 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -464,6 +464,9 @@ void __ref remove_pfn_range_from_zone(struct zone *zone, struct pglist_data *pgdat = zone->zone_pgdat; unsigned long flags; + /* Poison struct pages because they are now uninitialized again. */ + page_init_poison(pfn_to_page(start_pfn), sizeof(struct page) * nr_pages); + #ifdef CONFIG_ZONE_DEVICE /* * Zone shrinking code cannot properly deal with ZONE_DEVICE. So diff --git a/mm/memremap.c b/mm/memremap.c index 70263e6f093e..7fed8bd32a18 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -139,6 +139,8 @@ void memunmap_pages(struct dev_pagemap *pgmap) nid = page_to_nid(first_page); mem_hotplug_begin(); + remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(res->start), + PHYS_PFN(resource_size(res))); if (pgmap->type == MEMORY_DEVICE_PRIVATE) { __remove_pages(PHYS_PFN(res->start), PHYS_PFN(resource_size(res)), NULL); From patchwork Sun Oct 6 08:56:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176031 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 4DA141709 for ; Sun, 6 Oct 2019 08:57:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 360EA2133F for ; Sun, 6 Oct 2019 08:57:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726462AbfJFI5g (ORCPT ); Sun, 6 Oct 2019 04:57:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49174 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5g (ORCPT ); Sun, 6 Oct 2019 04:57:36 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 12B75307D853; Sun, 6 Oct 2019 08:57:36 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id 488265B681; Sun, 6 Oct 2019 08:57:33 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , Wei Yang Subject: [PATCH v6 07/10] mm/memory_hotplug: We always have a zone in find_(smallest|biggest)_section_pfn Date: Sun, 6 Oct 2019 10:56:43 +0200 Message-Id: <20191006085646.5768-8-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Sun, 06 Oct 2019 08:57:36 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org With shrink_pgdat_span() out of the way, we now always have a valid zone. Cc: Andrew Morton Cc: Oscar Salvador Cc: David Hildenbrand Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Cc: Wei Yang Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador Reviewed-by: Wei Yang --- mm/memory_hotplug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index bf5173e7913d..f294918f7211 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -337,7 +337,7 @@ static unsigned long find_smallest_section_pfn(int nid, struct zone *zone, if (unlikely(pfn_to_nid(start_pfn) != nid)) continue; - if (zone && zone != page_zone(pfn_to_page(start_pfn))) + if (zone != page_zone(pfn_to_page(start_pfn))) continue; return start_pfn; @@ -362,7 +362,7 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone, if (unlikely(pfn_to_nid(pfn) != nid)) continue; - if (zone && zone != page_zone(pfn_to_page(pfn))) + if (zone != page_zone(pfn_to_page(pfn))) continue; return pfn; From patchwork Sun Oct 6 08:56:44 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176039 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 D7E351862 for ; Sun, 6 Oct 2019 08:57:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BFA9F2133F for ; Sun, 6 Oct 2019 08:57:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726490AbfJFI5k (ORCPT ); Sun, 6 Oct 2019 04:57:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52294 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5j (ORCPT ); Sun, 6 Oct 2019 04:57:39 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2CB58C057EC0; Sun, 6 Oct 2019 08:57:39 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id 60EC55EE1D; Sun, 6 Oct 2019 08:57:36 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , Wei Yang Subject: [PATCH v6 08/10] mm/memory_hotplug: Don't check for "all holes" in shrink_zone_span() Date: Sun, 6 Oct 2019 10:56:44 +0200 Message-Id: <20191006085646.5768-9-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Sun, 06 Oct 2019 08:57:39 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org If we have holes, the holes will automatically get detected and removed once we remove the next bigger/smaller section. The extra checks can go. Cc: Andrew Morton Cc: Oscar Salvador Cc: Michal Hocko Cc: David Hildenbrand Cc: Pavel Tatashin Cc: Dan Williams Cc: Wei Yang Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador --- mm/memory_hotplug.c | 34 +++++++--------------------------- 1 file changed, 7 insertions(+), 27 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index f294918f7211..8dafa1ba8d9f 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -393,6 +393,9 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, if (pfn) { zone->zone_start_pfn = pfn; zone->spanned_pages = zone_end_pfn - pfn; + } else { + zone->zone_start_pfn = 0; + zone->spanned_pages = 0; } } else if (zone_end_pfn == end_pfn) { /* @@ -405,34 +408,11 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, start_pfn); if (pfn) zone->spanned_pages = pfn - zone_start_pfn + 1; + else { + zone->zone_start_pfn = 0; + zone->spanned_pages = 0; + } } - - /* - * The section is not biggest or smallest mem_section in the zone, it - * only creates a hole in the zone. So in this case, we need not - * change the zone. But perhaps, the zone has only hole data. Thus - * it check the zone has only hole or not. - */ - pfn = zone_start_pfn; - for (; pfn < zone_end_pfn; pfn += PAGES_PER_SUBSECTION) { - if (unlikely(!pfn_to_online_page(pfn))) - continue; - - if (page_zone(pfn_to_page(pfn)) != zone) - continue; - - /* Skip range to be removed */ - if (pfn >= start_pfn && pfn < end_pfn) - continue; - - /* If we find valid section, we have nothing to do */ - zone_span_writeunlock(zone); - return; - } - - /* The zone has no valid section */ - zone->zone_start_pfn = 0; - zone->spanned_pages = 0; zone_span_writeunlock(zone); } From patchwork Sun Oct 6 08:56:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176045 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 96D841862 for ; Sun, 6 Oct 2019 08:57:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7FB722133F for ; Sun, 6 Oct 2019 08:57:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726516AbfJFI5n (ORCPT ); Sun, 6 Oct 2019 04:57:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37458 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5m (ORCPT ); Sun, 6 Oct 2019 04:57:42 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5382B308123B; Sun, 6 Oct 2019 08:57:42 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id 85A435EE1D; Sun, 6 Oct 2019 08:57:39 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , Wei Yang Subject: [PATCH v6 09/10] mm/memory_hotplug: Drop local variables in shrink_zone_span() Date: Sun, 6 Oct 2019 10:56:45 +0200 Message-Id: <20191006085646.5768-10-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Sun, 06 Oct 2019 08:57:42 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org Get rid of the unnecessary local variables. Cc: Andrew Morton Cc: Oscar Salvador Cc: David Hildenbrand Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Cc: Wei Yang Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador Reviewed-by: Wei Yang --- mm/memory_hotplug.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 8dafa1ba8d9f..843481bd507d 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -374,14 +374,11 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone, static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, unsigned long end_pfn) { - unsigned long zone_start_pfn = zone->zone_start_pfn; - unsigned long z = zone_end_pfn(zone); /* zone_end_pfn namespace clash */ - unsigned long zone_end_pfn = z; unsigned long pfn; int nid = zone_to_nid(zone); zone_span_writelock(zone); - if (zone_start_pfn == start_pfn) { + if (zone->zone_start_pfn == start_pfn) { /* * If the section is smallest section in the zone, it need * shrink zone->zone_start_pfn and zone->zone_spanned_pages. @@ -389,25 +386,25 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, * for shrinking zone. */ pfn = find_smallest_section_pfn(nid, zone, end_pfn, - zone_end_pfn); + zone_end_pfn(zone)); if (pfn) { + zone->spanned_pages = zone_end_pfn(zone) - pfn; zone->zone_start_pfn = pfn; - zone->spanned_pages = zone_end_pfn - pfn; } else { zone->zone_start_pfn = 0; zone->spanned_pages = 0; } - } else if (zone_end_pfn == end_pfn) { + } else if (zone_end_pfn(zone) == end_pfn) { /* * If the section is biggest section in the zone, it need * shrink zone->spanned_pages. * In this case, we find second biggest valid mem_section for * shrinking zone. */ - pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn, + pfn = find_biggest_section_pfn(nid, zone, zone->zone_start_pfn, start_pfn); if (pfn) - zone->spanned_pages = pfn - zone_start_pfn + 1; + zone->spanned_pages = pfn - zone->zone_start_pfn + 1; else { zone->zone_start_pfn = 0; zone->spanned_pages = 0; From patchwork Sun Oct 6 08:56:46 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11176047 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 BA83C1709 for ; Sun, 6 Oct 2019 08:57:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A28E12133F for ; Sun, 6 Oct 2019 08:57:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726224AbfJFI5q (ORCPT ); Sun, 6 Oct 2019 04:57:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52152 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726185AbfJFI5p (ORCPT ); Sun, 6 Oct 2019 04:57:45 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 75465368CF; Sun, 6 Oct 2019 08:57:45 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-58.ams2.redhat.com [10.36.116.58]) by smtp.corp.redhat.com (Postfix) with ESMTP id ABE055EE1D; Sun, 6 Oct 2019 08:57:42 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , Andrew Morton , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , Wei Yang Subject: [PATCH v6 10/10] mm/memory_hotplug: Cleanup __remove_pages() Date: Sun, 6 Oct 2019 10:56:46 +0200 Message-Id: <20191006085646.5768-11-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> References: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Sun, 06 Oct 2019 08:57:45 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org Let's drop the basically unused section stuff and simplify. Also, let's use a shorter variant to calculate the number of pages to the next section boundary. Cc: Andrew Morton Cc: Oscar Salvador Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Cc: Wei Yang Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador Reviewed-by: Wei Yang --- mm/memory_hotplug.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 843481bd507d..2275240cfa10 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -490,25 +490,20 @@ static void __remove_section(unsigned long pfn, unsigned long nr_pages, void __remove_pages(unsigned long pfn, unsigned long nr_pages, struct vmem_altmap *altmap) { + const unsigned long end_pfn = pfn + nr_pages; + unsigned long cur_nr_pages; unsigned long map_offset = 0; - unsigned long nr, start_sec, end_sec; map_offset = vmem_altmap_offset(altmap); if (check_pfn_span(pfn, nr_pages, "remove")) return; - start_sec = pfn_to_section_nr(pfn); - end_sec = pfn_to_section_nr(pfn + nr_pages - 1); - for (nr = start_sec; nr <= end_sec; nr++) { - unsigned long pfns; - + for (; pfn < end_pfn; pfn += cur_nr_pages) { cond_resched(); - pfns = min(nr_pages, PAGES_PER_SECTION - - (pfn & ~PAGE_SECTION_MASK)); - __remove_section(pfn, pfns, map_offset, altmap); - pfn += pfns; - nr_pages -= pfns; + /* Select all remaining pages up to the next section boundary */ + cur_nr_pages = min(end_pfn - pfn, -(pfn | PAGE_SECTION_MASK)); + __remove_section(pfn, cur_nr_pages, map_offset, altmap); map_offset = 0; } }