From patchwork Wed Nov 14 22:49:14 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Keith Busch X-Patchwork-Id: 10683279 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 F33A413BF for ; Wed, 14 Nov 2018 22:53:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E3CED2BF63 for ; Wed, 14 Nov 2018 22:53:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D63102BF72; Wed, 14 Nov 2018 22:53:04 +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 772B42BF63 for ; Wed, 14 Nov 2018 22:53:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726814AbeKOI6Q (ORCPT ); Thu, 15 Nov 2018 03:58:16 -0500 Received: from mga12.intel.com ([192.55.52.136]:50974 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726379AbeKOI6Q (ORCPT ); Thu, 15 Nov 2018 03:58:16 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Nov 2018 14:53:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,234,1539673200"; d="scan'208";a="106314877" Received: from unknown (HELO localhost.lm.intel.com) ([10.232.112.69]) by fmsmga004.fm.intel.com with ESMTP; 14 Nov 2018 14:53:02 -0800 From: Keith Busch To: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org Cc: Greg Kroah-Hartman , Rafael Wysocki , Dave Hansen , Dan Williams , Keith Busch Subject: [PATCH 1/7] node: Link memory nodes to their compute nodes Date: Wed, 14 Nov 2018 15:49:14 -0700 Message-Id: <20181114224921.12123-2-keith.busch@intel.com> X-Mailer: git-send-email 2.13.6 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Memory-only nodes will often have affinity to a compute node, and platforms have ways to express that locality relationship. A node containing CPUs or other DMA devices that can initiate memory access are referred to as "memory iniators". A "memory target" is a node that provides at least one phyiscal address range accessible to a memory initiator. In preparation for these systems, provide a new kernel API to link the target memory node to its initiator compute node with symlinks to each other. The following example shows the new sysfs hierarchy setup for memory node 'Y' local to commpute node 'X': # ls -l /sys/devices/system/node/nodeX/initiator* /sys/devices/system/node/nodeX/targetY -> ../nodeY # ls -l /sys/devices/system/node/nodeY/target* /sys/devices/system/node/nodeY/initiatorX -> ../nodeX Signed-off-by: Keith Busch --- drivers/base/node.c | 32 ++++++++++++++++++++++++++++++++ include/linux/node.h | 2 ++ 2 files changed, 34 insertions(+) diff --git a/drivers/base/node.c b/drivers/base/node.c index 86d6cd92ce3d..a9b7512a9502 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -372,6 +372,38 @@ int register_cpu_under_node(unsigned int cpu, unsigned int nid) kobject_name(&node_devices[nid]->dev.kobj)); } +int register_memory_node_under_compute_node(unsigned int m, unsigned int p) +{ + int ret; + char initiator[20], target[17]; + + if (!node_online(p) || !node_online(m)) + return -ENODEV; + if (m == p) + return 0; + + snprintf(initiator, sizeof(initiator), "initiator%d", p); + snprintf(target, sizeof(target), "target%d", m); + + ret = sysfs_create_link(&node_devices[p]->dev.kobj, + &node_devices[m]->dev.kobj, + target); + if (ret) + return ret; + + ret = sysfs_create_link(&node_devices[m]->dev.kobj, + &node_devices[p]->dev.kobj, + initiator); + if (ret) + goto err; + + return 0; + err: + sysfs_remove_link(&node_devices[p]->dev.kobj, + kobject_name(&node_devices[m]->dev.kobj)); + return ret; +} + int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) { struct device *obj; diff --git a/include/linux/node.h b/include/linux/node.h index 257bb3d6d014..1fd734a3fb3f 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -75,6 +75,8 @@ extern int register_mem_sect_under_node(struct memory_block *mem_blk, extern int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, unsigned long phys_index); +extern int register_memory_node_under_compute_node(unsigned int m, unsigned int p); + #ifdef CONFIG_HUGETLBFS extern void register_hugetlbfs_with_node(node_registration_func_t doregister, node_registration_func_t unregister);