From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3yLHjw2gMnzDqjm for ; Tue, 24 Oct 2017 00:46:12 +1100 (AEDT) Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v9NDi6Sp136738 for ; Mon, 23 Oct 2017 09:46:09 -0400 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0b-001b2d01.pphosted.com with ESMTP id 2dshetrgau-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 23 Oct 2017 09:46:09 -0400 Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 23 Oct 2017 07:46:08 -0600 To: linux-kernel@vger.kernel.org, Michael Ellerman , Michael Bringmann , "Cc: John Allen" , Nathan Fontenot , linuxppc-dev@lists.ozlabs.org Cc: Tyrel Datwyler , Thomas Falcon In-Reply-To: <79edcd04-4e59-461c-4480-bad51ba21196@linux.vnet.ibm.com> From: Michael Bringmann Subject: [PATCH V3 1/2] pseries/nodes: Ensure enough nodes avail for operations Date: Mon, 23 Oct 2017 08:46:02 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Message-Id: List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , pseries/nodes: On pseries systems which allow 'hot-add' of CPU or memory resources, it may occur that the new resources are to be inserted into nodes that were not used for these resources at bootup. In the kernel, any node that is used must be defined and initialized. This patch ensures that sufficient nodes are defined to support configuration requirements after boot, as well as at boot. This patch extracts the value of the lowest domain level (number of allocable resources) from the device tree property "ibm,max-associativity-domains" to use as the maximum number of nodes to setup as possibly available in the system. This new setting will override the instruction, nodes_and(node_possible_map, node_possible_map, node_online_map); presently seen in the function arch/powerpc/mm/numa.c:initmem_init(). If the property is not present at boot, no operation will be performed to define or enable additional nodes. Signed-off-by: Michael Bringmann --- arch/powerpc/mm/numa.c | 39 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 36 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index ec098b3..f885ab7 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -892,6 +892,36 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn) NODE_DATA(nid)->node_spanned_pages = spanned_pages; } +static void __init find_possible_nodes(void) +{ + struct device_node *rtas; + u32 numnodes, i; + + if (min_common_depth <= 0) + return; + + rtas = of_find_node_by_path("/rtas"); + if (!rtas) + return; + + if (of_property_read_u32_index(rtas, + "ibm,max-associativity-domains", + min_common_depth, &numnodes)) + goto out; + + pr_info("numa: Nodes = %d (mcd = %d)\n", numnodes, + min_common_depth); + + for (i = 0; i < numnodes; i++) { + if (!node_possible(i)) + node_set(i, node_possible_map); + } + +out: + if (rtas) + of_node_put(rtas); +} + void __init initmem_init(void) { int nid, cpu; @@ -905,12 +935,15 @@ void __init initmem_init(void) memblock_dump_all(); /* - * Reduce the possible NUMA nodes to the online NUMA nodes, - * since we do not support node hotplug. This ensures that we - * lower the maximum NUMA node ID to what is actually present. + * Modify the set of possible NUMA nodes to reflect information + * available about the set of online nodes, and the set of nodes + * that we expect to make use of for this platform's affinity + * calculations. */ nodes_and(node_possible_map, node_possible_map, node_online_map); + find_possible_nodes(); + for_each_online_node(nid) { unsigned long start_pfn, end_pfn;