From patchwork Mon May 27 11:11:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 10962577 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 87328933 for ; Mon, 27 May 2019 11:12:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 76E4B28AD4 for ; Mon, 27 May 2019 11:12:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6B14128AE8; Mon, 27 May 2019 11:12:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ADA1D28AD4 for ; Mon, 27 May 2019 11:12:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726527AbfE0LMw (ORCPT ); Mon, 27 May 2019 07:12:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58066 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725996AbfE0LMw (ORCPT ); Mon, 27 May 2019 07:12:52 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 48FDA3086214; Mon, 27 May 2019 11:12:51 +0000 (UTC) Received: from t460s.redhat.com (ovpn-117-89.ams2.redhat.com [10.36.117.89]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3CE8B19C7F; Mon, 27 May 2019 11:12:43 +0000 (UTC) From: David Hildenbrand To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, Dan Williams , Wei Yang , Igor Mammedov , David Hildenbrand , Greg Kroah-Hartman , "Rafael J. Wysocki" , "mike.travis@hpe.com" , Ingo Molnar , Andrew Banman , Oscar Salvador , Michal Hocko , Pavel Tatashin , Qian Cai , Arun KS , Mathieu Malaterre Subject: [PATCH v3 07/11] mm/memory_hotplug: Create memory block devices after arch_add_memory() Date: Mon, 27 May 2019 13:11:48 +0200 Message-Id: <20190527111152.16324-8-david@redhat.com> In-Reply-To: <20190527111152.16324-1-david@redhat.com> References: <20190527111152.16324-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Mon, 27 May 2019 11:12:51 +0000 (UTC) Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Only memory to be added to the buddy and to be onlined/offlined by user space using /sys/devices/system/memory/... needs (and should have!) memory block devices. Factor out creation of memory block devices. Create all devices after arch_add_memory() succeeded. We can later drop the want_memblock parameter, because it is now effectively stale. Only after memory block devices have been added, memory can be onlined by user space. This implies, that memory is not visible to user space at all before arch_add_memory() succeeded. While at it - use WARN_ON_ONCE instead of BUG_ON in moved unregister_memory() - introduce find_memory_block_by_id() to search via block id - Use find_memory_block_by_id() in init_memory_block() to catch duplicates Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: David Hildenbrand Cc: "mike.travis@hpe.com" Cc: Andrew Morton Cc: Ingo Molnar Cc: Andrew Banman Cc: Oscar Salvador Cc: Michal Hocko Cc: Pavel Tatashin Cc: Qian Cai Cc: Wei Yang Cc: Arun KS Cc: Mathieu Malaterre Signed-off-by: David Hildenbrand Reviewed-by: Pavel Tatashin Acked-by: Michal Hocko --- drivers/base/memory.c | 82 +++++++++++++++++++++++++++--------------- include/linux/memory.h | 2 +- mm/memory_hotplug.c | 15 ++++---- 3 files changed, 63 insertions(+), 36 deletions(-) diff --git a/drivers/base/memory.c b/drivers/base/memory.c index ac17c95a5f28..5a0370f0c506 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -39,6 +39,11 @@ static inline int base_memory_block_id(int section_nr) return section_nr / sections_per_block; } +static inline int pfn_to_block_id(unsigned long pfn) +{ + return base_memory_block_id(pfn_to_section_nr(pfn)); +} + static int memory_subsys_online(struct device *dev); static int memory_subsys_offline(struct device *dev); @@ -582,10 +587,9 @@ int __weak arch_get_memory_phys_device(unsigned long start_pfn) * A reference for the returned object is held and the reference for the * hinted object is released. */ -struct memory_block *find_memory_block_hinted(struct mem_section *section, - struct memory_block *hint) +static struct memory_block *find_memory_block_by_id(int block_id, + struct memory_block *hint) { - int block_id = base_memory_block_id(__section_nr(section)); struct device *hintdev = hint ? &hint->dev : NULL; struct device *dev; @@ -597,6 +601,14 @@ struct memory_block *find_memory_block_hinted(struct mem_section *section, return to_memory_block(dev); } +struct memory_block *find_memory_block_hinted(struct mem_section *section, + struct memory_block *hint) +{ + int block_id = base_memory_block_id(__section_nr(section)); + + return find_memory_block_by_id(block_id, hint); +} + /* * For now, we have a linear search to go find the appropriate * memory_block corresponding to a particular phys_index. If @@ -658,6 +670,11 @@ static int init_memory_block(struct memory_block **memory, int block_id, unsigned long start_pfn; int ret = 0; + mem = find_memory_block_by_id(block_id, NULL); + if (mem) { + put_device(&mem->dev); + return -EEXIST; + } mem = kzalloc(sizeof(*mem), GFP_KERNEL); if (!mem) return -ENOMEM; @@ -699,44 +716,53 @@ static int add_memory_block(int base_section_nr) return 0; } +static void unregister_memory(struct memory_block *memory) +{ + if (WARN_ON_ONCE(memory->dev.bus != &memory_subsys)) + return; + + /* drop the ref. we got via find_memory_block() */ + put_device(&memory->dev); + device_unregister(&memory->dev); +} + /* - * need an interface for the VM to add new memory regions, - * but without onlining it. + * Create memory block devices for the given memory area. Start and size + * have to be aligned to memory block granularity. Memory block devices + * will be initialized as offline. */ -int hotplug_memory_register(int nid, struct mem_section *section) +int create_memory_block_devices(unsigned long start, unsigned long size) { - int block_id = base_memory_block_id(__section_nr(section)); - int ret = 0; + const int start_block_id = pfn_to_block_id(PFN_DOWN(start)); + int end_block_id = pfn_to_block_id(PFN_DOWN(start + size)); struct memory_block *mem; + unsigned long block_id; + int ret = 0; - mutex_lock(&mem_sysfs_mutex); + if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) || + !IS_ALIGNED(size, memory_block_size_bytes()))) + return -EINVAL; - mem = find_memory_block(section); - if (mem) { - mem->section_count++; - put_device(&mem->dev); - } else { + mutex_lock(&mem_sysfs_mutex); + for (block_id = start_block_id; block_id != end_block_id; block_id++) { ret = init_memory_block(&mem, block_id, MEM_OFFLINE); if (ret) - goto out; - mem->section_count++; + break; + mem->section_count = sections_per_block; + } + if (ret) { + end_block_id = block_id; + for (block_id = start_block_id; block_id != end_block_id; + block_id++) { + mem = find_memory_block_by_id(block_id, NULL); + mem->section_count = 0; + unregister_memory(mem); + } } - -out: mutex_unlock(&mem_sysfs_mutex); return ret; } -static void -unregister_memory(struct memory_block *memory) -{ - BUG_ON(memory->dev.bus != &memory_subsys); - - /* drop the ref. we got via find_memory_block() */ - put_device(&memory->dev); - device_unregister(&memory->dev); -} - void unregister_memory_section(struct mem_section *section) { struct memory_block *mem; diff --git a/include/linux/memory.h b/include/linux/memory.h index 474c7c60c8f2..db3e8567f900 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -111,7 +111,7 @@ extern int register_memory_notifier(struct notifier_block *nb); extern void unregister_memory_notifier(struct notifier_block *nb); extern int register_memory_isolate_notifier(struct notifier_block *nb); extern void unregister_memory_isolate_notifier(struct notifier_block *nb); -int hotplug_memory_register(int nid, struct mem_section *section); +int create_memory_block_devices(unsigned long start, unsigned long size); extern void unregister_memory_section(struct mem_section *); extern int memory_dev_init(void); extern int memory_notify(unsigned long val, void *v); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 4b9d2974f86c..b1fde90bbf19 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -259,13 +259,7 @@ static int __meminit __add_section(int nid, unsigned long phys_start_pfn, return -EEXIST; ret = sparse_add_one_section(nid, phys_start_pfn, altmap); - if (ret < 0) - return ret; - - if (!want_memblock) - return 0; - - return hotplug_memory_register(nid, __pfn_to_section(phys_start_pfn)); + return ret < 0 ? ret : 0; } /* @@ -1107,6 +1101,13 @@ int __ref add_memory_resource(int nid, struct resource *res) if (ret < 0) goto error; + /* create memory block devices after memory was added */ + ret = create_memory_block_devices(start, size); + if (ret) { + arch_remove_memory(nid, start, size, NULL); + goto error; + } + if (new_node) { /* If sysfs file of new node can't be created, cpu on the node * can't be hot-added. There is no rollback way now.