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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 98874C43381 for ; Thu, 14 Feb 2019 17:11:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6CB3A222DA for ; Thu, 14 Feb 2019 17:11:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394420AbfBNRK7 (ORCPT ); Thu, 14 Feb 2019 12:10:59 -0500 Received: from mga05.intel.com ([192.55.52.43]:10409 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726218AbfBNRK4 (ORCPT ); Thu, 14 Feb 2019 12:10:56 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Feb 2019 09:10:40 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,369,1544515200"; d="scan'208";a="133613118" Received: from unknown (HELO localhost.lm.intel.com) ([10.232.112.69]) by FMSMGA003.fm.intel.com with ESMTP; 14 Feb 2019 09:10:40 -0800 From: Keith Busch To: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org Cc: Greg Kroah-Hartman , Rafael Wysocki , Dave Hansen , Dan Williams , Keith Busch Subject: [PATCHv6 05/10] node: Add heterogenous memory access attributes Date: Thu, 14 Feb 2019 10:10:12 -0700 Message-Id: <20190214171017.9362-6-keith.busch@intel.com> X-Mailer: git-send-email 2.13.6 In-Reply-To: <20190214171017.9362-1-keith.busch@intel.com> References: <20190214171017.9362-1-keith.busch@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Heterogeneous memory systems provide memory nodes with different latency and bandwidth performance attributes. Provide a new kernel interface for subsystems to register the attributes under the memory target node's initiator access class. If the system provides this information, applications may query these attributes when deciding which node to request memory. The following example shows the new sysfs hierarchy for a node exporting performance attributes: # tree -P "read*|write*"/sys/devices/system/node/nodeY/accessZ/initiators/ /sys/devices/system/node/nodeY/accessZ/initiators/ |-- read_bandwidth |-- read_latency |-- write_bandwidth `-- write_latency The bandwidth is exported as MB/s and latency is reported in nanoseconds. The values are taken from the platform as reported by the manufacturer. Memory accesses from an initiator node that is not one of the memory's access "Z" initiator nodes linked in the same directory may observe different performance than reported here. When a subsystem makes use of this interface, initiators of a different access number may not have the same performance relative to initiators in other access numbers, or omitted from the any access class' initiators. Descriptions for memory access initiator performance access attributes are added to sysfs stable documentation. Signed-off-by: Keith Busch --- Documentation/ABI/stable/sysfs-devices-node | 31 ++++++++++++++- drivers/base/Kconfig | 8 ++++ drivers/base/node.c | 59 +++++++++++++++++++++++++++++ include/linux/node.h | 19 ++++++++++ 4 files changed, 116 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node index fb843222a281..cd64b62152ba 100644 --- a/Documentation/ABI/stable/sysfs-devices-node +++ b/Documentation/ABI/stable/sysfs-devices-node @@ -106,7 +106,8 @@ Description: nodes that have class "Y" access to this target node's memory. CPUs and other memory initiators in nodes not in the list accessing this node's memory may have different - performance. + performance. This directory also provides the performance + attributes if they exist. What: /sys/devices/system/node/nodeX/classY/targets/ Date: December 2018 @@ -114,3 +115,31 @@ Contact: Keith Busch Description: The directory containing symlinks to memory targets that this initiator node has class "Y" access. + +What: /sys/devices/system/node/nodeX/accessY/initiators/read_bandwidth +Date: December 2018 +Contact: Keith Busch +Description: + This node's read bandwidth in MB/s when accessed from + nodes found in this access class's linked initiators. + +What: /sys/devices/system/node/nodeX/accessY/initiators/read_latency +Date: December 2018 +Contact: Keith Busch +Description: + This node's read latency in nanoseconds when accessed + from nodes found in this access class's linked initiators. + +What: /sys/devices/system/node/nodeX/accessY/initiators/write_bandwidth +Date: December 2018 +Contact: Keith Busch +Description: + This node's write bandwidth in MB/s when accessed from + found in this access class's linked initiators. + +What: /sys/devices/system/node/nodeX/accessY/initiators/write_latency +Date: December 2018 +Contact: Keith Busch +Description: + This node's write latency in nanoseconds when access + from nodes found in this class's linked initiators. diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index 3e63a900b330..32dc81bd7056 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -149,6 +149,14 @@ config DEBUG_TEST_DRIVER_REMOVE unusable. You should say N here unless you are explicitly looking to test this functionality. +config HMEM_REPORTING + bool + default n + depends on NUMA + help + Enable reporting for heterogenous memory access attributes under + their non-uniform memory nodes. + source "drivers/base/test/Kconfig" config SYS_HYPERVISOR diff --git a/drivers/base/node.c b/drivers/base/node.c index d1ec38db4e77..a1795c9c9f7d 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -71,6 +71,9 @@ struct node_access_nodes { struct device dev; struct list_head list_node; unsigned access; +#ifdef CONFIG_HMEM_REPORTING + struct node_hmem_attrs hmem_attrs; +#endif }; #define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev) @@ -148,6 +151,62 @@ static struct node_access_nodes *node_init_node_access(struct node *node, return NULL; } +#ifdef CONFIG_HMEM_REPORTING +#define ACCESS_ATTR(name) \ +static ssize_t name##_show(struct device *dev, \ + struct device_attribute *attr, \ + char *buf) \ +{ \ + return sprintf(buf, "%u\n", to_access_nodes(dev)->hmem_attrs.name); \ +} \ +static DEVICE_ATTR_RO(name); + +ACCESS_ATTR(read_bandwidth) +ACCESS_ATTR(read_latency) +ACCESS_ATTR(write_bandwidth) +ACCESS_ATTR(write_latency) + +static struct attribute *access_attrs[] = { + &dev_attr_read_bandwidth.attr, + &dev_attr_read_latency.attr, + &dev_attr_write_bandwidth.attr, + &dev_attr_write_latency.attr, + NULL, +}; + +/** + * node_set_perf_attrs - Set the performance values for given access class + * @nid: Node identifier to be set + * @hmem_attrs: Heterogeneous memory performance attributes + * @access: The access class the for the given attributes + */ +void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, + unsigned access) +{ + struct node_access_nodes *c; + struct node *node; + int i; + + if (WARN_ON_ONCE(!node_online(nid))) + return; + + node = node_devices[nid]; + c = node_init_node_access(node, access); + if (!c) + return; + + c->hmem_attrs = *hmem_attrs; + for (i = 0; access_attrs[i] != NULL; i++) { + if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i], + "initiators")) { + pr_info("failed to add performance attribute to node %d\n", + nid); + break; + } + } +} +#endif + #define K(x) ((x) << (PAGE_SHIFT - 10)) static ssize_t node_read_meminfo(struct device *dev, struct device_attribute *attr, char *buf) diff --git a/include/linux/node.h b/include/linux/node.h index f34688a203c1..2db077363d9c 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -20,6 +20,25 @@ #include #include +#ifdef CONFIG_HMEM_REPORTING +/** + * struct node_hmem_attrs - heterogeneous memory performance attributes + * + * @read_bandwidth: Read bandwidth in MB/s + * @write_bandwidth: Write bandwidth in MB/s + * @read_latency: Read latency in nanoseconds + * @write_latency: Write latency in nanoseconds + */ +struct node_hmem_attrs { + unsigned int read_bandwidth; + unsigned int write_bandwidth; + unsigned int read_latency; + unsigned int write_latency; +}; +void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, + unsigned access); +#endif + struct node { struct device dev; struct list_head access_list; -- 2.14.4