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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 DABA7C2D0DB for ; Tue, 28 Jan 2020 14:30:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD6822469D for ; Tue, 28 Jan 2020 14:30:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580221812; bh=YfVryHKCUHFqeiK6OVMBMqEy9HNBIyunMElfIaNeGUU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=pcZTtzLUiiAk0HtRTCFM3AW3u5AM3c8xwdP9uOQM4UmwxJmod4s3AyDZmGAewXoDw XACROsl+d3gT99hAZgaVWo3m8vZo/zbl3+Su6a/OqmEyMfLT3N+DdVVrrXY/yJ138q iYZdgrOAsP7qMb9J4bfQ7Qedse+C9VOtJgebdQrw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727232AbgA1OaI (ORCPT ); Tue, 28 Jan 2020 09:30:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:59658 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729368AbgA1OaI (ORCPT ); Tue, 28 Jan 2020 09:30:08 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E8FC024699; Tue, 28 Jan 2020 14:30:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580221807; bh=YfVryHKCUHFqeiK6OVMBMqEy9HNBIyunMElfIaNeGUU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MICCQNDlsNfba5V2kaSh8aUGyn6gkt1N+cEUmInT0UzmW5ZPWjpRzYfgF3NtLbACj fWKEZGtDYCJ5VUnKHtfvdBVgWCkSaN89XvTWLAmwAtHJoChvx9ANgMAE+fmE1GNzpq gGRF1YAgtKKS57n3eTgLEssqkjSQ0foeiiEO+3Vg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , David Hildenbrand , "Rafael J. Wysocki" , Stephen Rothwell , Pavel Tatashin , Michal Hocko , Oscar Salvador , Andrew Morton , Linus Torvalds Subject: [PATCH 4.19 89/92] drivers/base/node.c: simplify unregister_memory_block_under_nodes() Date: Tue, 28 Jan 2020 15:08:57 +0100 Message-Id: <20200128135820.893455279@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200128135809.344954797@linuxfoundation.org> References: <20200128135809.344954797@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: David Hildenbrand commit d84f2f5a755208da3f93e17714631485cb3da11c upstream. We don't allow to offline memory block devices that belong to multiple numa nodes. Therefore, such devices can never get removed. It is sufficient to process a single node when removing the memory block. No need to iterate over each and every PFN. We already have the nid stored for each memory block. Make sure that the nid always has a sane value. Please note that checking for node_online(nid) is not required. If we would have a memory block belonging to a node that is no longer offline, then we would have a BUG in the node offlining code. Link: http://lkml.kernel.org/r/20190719135244.15242-1-david@redhat.com Signed-off-by: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: David Hildenbrand Cc: Stephen Rothwell Cc: Pavel Tatashin Cc: Michal Hocko Cc: Oscar Salvador Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: David Hildenbrand Signed-off-by: Greg Kroah-Hartman --- drivers/base/memory.c | 1 + drivers/base/node.c | 39 +++++++++++++++------------------------ 2 files changed, 16 insertions(+), 24 deletions(-) --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -693,6 +693,7 @@ static int init_memory_block(struct memo mem->state = state; start_pfn = section_nr_to_pfn(mem->start_section_nr); mem->phys_device = arch_get_memory_phys_device(start_pfn); + mem->nid = NUMA_NO_NODE; ret = register_memory(mem); --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -409,8 +409,6 @@ int register_mem_sect_under_node(struct int ret, nid = *(int *)arg; unsigned long pfn, sect_start_pfn, sect_end_pfn; - mem_blk->nid = nid; - sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr); sect_end_pfn += PAGES_PER_SECTION - 1; @@ -439,6 +437,13 @@ int register_mem_sect_under_node(struct if (page_nid != nid) continue; } + + /* + * If this memory block spans multiple nodes, we only indicate + * the last processed node. + */ + mem_blk->nid = nid; + ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, &mem_blk->dev.kobj, kobject_name(&mem_blk->dev.kobj)); @@ -454,32 +459,18 @@ int register_mem_sect_under_node(struct } /* - * Unregister memory block device under all nodes that it spans. - * Has to be called with mem_sysfs_mutex held (due to unlinked_nodes). + * Unregister a memory block device under the node it spans. Memory blocks + * with multiple nodes cannot be offlined and therefore also never be removed. */ void unregister_memory_block_under_nodes(struct memory_block *mem_blk) { - unsigned long pfn, sect_start_pfn, sect_end_pfn; - static nodemask_t unlinked_nodes; - - nodes_clear(unlinked_nodes); - sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); - sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr); - for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { - int nid; + if (mem_blk->nid == NUMA_NO_NODE) + return; - nid = get_nid_for_pfn(pfn); - if (nid < 0) - continue; - if (!node_online(nid)) - continue; - if (node_test_and_set(nid, unlinked_nodes)) - continue; - sysfs_remove_link(&node_devices[nid]->dev.kobj, - kobject_name(&mem_blk->dev.kobj)); - sysfs_remove_link(&mem_blk->dev.kobj, - kobject_name(&node_devices[nid]->dev.kobj)); - } + sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj, + kobject_name(&mem_blk->dev.kobj)); + sysfs_remove_link(&mem_blk->dev.kobj, + kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); } int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn)