From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f173.google.com (mail-pd0-f173.google.com [209.85.192.173]) by kanga.kvack.org (Postfix) with ESMTP id 22AC26B0035 for ; Fri, 11 Apr 2014 07:00:24 -0400 (EDT) Received: by mail-pd0-f173.google.com with SMTP id z10so5147891pdj.18 for ; Fri, 11 Apr 2014 04:00:23 -0700 (PDT) Received: from mail-pb0-x231.google.com (mail-pb0-x231.google.com [2607:f8b0:400e:c01::231]) by mx.google.com with ESMTPS id hf1si145650pac.163.2014.04.11.04.00.22 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 11 Apr 2014 04:00:23 -0700 (PDT) Received: by mail-pb0-f49.google.com with SMTP id jt11so5258230pbb.36 for ; Fri, 11 Apr 2014 04:00:22 -0700 (PDT) Date: Fri, 11 Apr 2014 04:00:20 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH] drivers/base/node.c: export physical address range of given node (Re: NUMA node information for pages) In-Reply-To: <53474709.e59ec20a.3bd5.3b91SMTPIN_ADDED_BROKEN@mx.google.com> Message-ID: References: <87eh1ix7g0.fsf@x240.local.i-did-not-set--mail-host-address--so-tickle-me> <533a1563.ad318c0a.6a93.182bSMTPIN_ADDED_BROKEN@mx.google.com> <5343806c.100cc30a.0461.ffffc401SMTPIN_ADDED_BROKEN@mx.google.com> <5345fe27.82dab40a.0831.0af9SMTPIN_ADDED_BROKEN@mx.google.com> <53474709.e59ec20a.3bd5.3b91SMTPIN_ADDED_BROKEN@mx.google.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi Cc: drepper@gmail.com, anatol.pomozov@gmail.com, jkosina@suse.cz, akpm@linux-foundation.org, xemul@parallels.com, paul.gortmaker@windriver.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org On Thu, 10 Apr 2014, Naoya Horiguchi wrote: > Yes, that's right, but it seems to me that just node_start_pfn and node_end_pfn > is not enough because there can be holes (without any page struct backed) inside > [node_start_pfn, node_end_pfn), and it's not aware of memory hotplug. > So? Who cares if there are non-addressable holes in part of the span? Ulrich, correct me if I'm wrong, but it seems you're looking for just a address-to-nodeid mapping (or pfn-to-nodeid mapping) and aren't actually expecting that there are no holes in a node for things like acpi or I/O or reserved memory. The node spans a contiguous length of memory, there's no consideration for addresses that aren't actually backed by physical memory. We are just representing proximity domains that have a base address and length in the acpi world. Memory hotplug is already taken care of because onlining and offlining nodes already add these node classes and {start,end}_phys_addr would show up automatically. If you use node_start_pfn(nid) and node_end_pfn(nid) as suggested, there's no futher consideration needed for hotplug. I think trying to represent holes and handling different memory models and hotplug in special ways is complete overkill. Ulrich, can I have your ack? --- Documentation/ABI/stable/sysfs-devices-node | 12 ++++++++++++ drivers/base/node.c | 18 ++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node --- a/Documentation/ABI/stable/sysfs-devices-node +++ b/Documentation/ABI/stable/sysfs-devices-node @@ -63,6 +63,18 @@ Description: The node's hit/miss statistics, in units of pages. See Documentation/numastat.txt +What: /sys/devices/system/node/nodeX/start_phys_addr +Date: April 2014 +Contact: David Rientjes +Description: + The physical base address of this node. + +What: /sys/devices/system/node/nodeX/end_phys_addr +Date: April 2014 +Contact: David Rientjes +Description: + The physical base + length address of this node. + What: /sys/devices/system/node/nodeX/distance Date: October 2002 Contact: Linux Memory Management list diff --git a/drivers/base/node.c b/drivers/base/node.c --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -170,6 +170,20 @@ static ssize_t node_read_numastat(struct device *dev, } static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL); +static ssize_t node_read_start_phys_addr(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "0x%lx\n", node_start_pfn(dev->id) << PAGE_SHIFT); +} +static DEVICE_ATTR(start_phys_addr, S_IRUGO, node_read_start_phys_addr, NULL); + +static ssize_t node_read_end_phys_addr(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "0x%lx\n", node_end_pfn(dev->id) << PAGE_SHIFT); +} +static DEVICE_ATTR(end_phys_addr, S_IRUGO, node_read_end_phys_addr, NULL); + static ssize_t node_read_vmstat(struct device *dev, struct device_attribute *attr, char *buf) { @@ -286,6 +300,8 @@ static int register_node(struct node *node, int num, struct node *parent) device_create_file(&node->dev, &dev_attr_cpulist); device_create_file(&node->dev, &dev_attr_meminfo); device_create_file(&node->dev, &dev_attr_numastat); + device_create_file(&node->dev, &dev_attr_start_phys_addr); + device_create_file(&node->dev, &dev_attr_end_phys_addr); device_create_file(&node->dev, &dev_attr_distance); device_create_file(&node->dev, &dev_attr_vmstat); @@ -311,6 +327,8 @@ void unregister_node(struct node *node) device_remove_file(&node->dev, &dev_attr_cpulist); device_remove_file(&node->dev, &dev_attr_meminfo); device_remove_file(&node->dev, &dev_attr_numastat); + device_remove_file(&node->dev, &dev_attr_start_phys_addr); + device_remove_file(&node->dev, &dev_attr_end_phys_addr); device_remove_file(&node->dev, &dev_attr_distance); device_remove_file(&node->dev, &dev_attr_vmstat); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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