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[148.163.156.1]) by mx.google.com with ESMTPS id v187si33560423pfb.258.2016.09.05.22.34.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 05 Sep 2016 22:34:55 -0700 (PDT) Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u865X1mg089513 for ; Tue, 6 Sep 2016 01:34:53 -0400 Received: from e23smtp03.au.ibm.com (e23smtp03.au.ibm.com [202.81.31.145]) by mx0a-001b2d01.pphosted.com with ESMTP id 259d2rm1x7-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 06 Sep 2016 01:34:53 -0400 Received: from localhost by e23smtp03.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 6 Sep 2016 15:34:49 +1000 Received: from d23relay07.au.ibm.com (d23relay07.au.ibm.com [9.190.26.37]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id E7F4E3578053 for ; Tue, 6 Sep 2016 15:34:35 +1000 (EST) Received: from d23av06.au.ibm.com (d23av06.au.ibm.com [9.190.235.151]) by d23relay07.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u865YZoe4915580 for ; Tue, 6 Sep 2016 15:34:35 +1000 Received: from d23av06.au.ibm.com (localhost [127.0.0.1]) by d23av06.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u865YZcw011753 for ; Tue, 6 Sep 2016 15:34:35 +1000 From: Anshuman Khandual Subject: [PATCH V2 2/2] mm: Add sysfs interface to dump each node's zonelist information Date: Tue, 6 Sep 2016 11:04:32 +0530 In-Reply-To: <1473140072-24137-1-git-send-email-khandual@linux.vnet.ibm.com> References: <1473140072-24137-1-git-send-email-khandual@linux.vnet.ibm.com> Message-Id: <1473140072-24137-2-git-send-email-khandual@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org Each individual node in the system has a ZONELIST_FALLBACK zonelist and a ZONELIST_NOFALLBACK zonelist. These zonelists decide fallback order of zones during memory allocations. Sometimes it helps to dump these zonelists to see the priority order of various zones in them. Particularly platforms which support memory hotplug into previously non existing zones (at boot), this interface helps in visualizing which all zonelists of the system at what priority level, the new hot added memory ends up in. POWER is such a platform where all the memory detected during boot time remains with ZONE_DMA for good but then hot plug process can actually get new memory into ZONE_MOVABLE. So having a way to get the snapshot of the zonelists on the system after memory or node hot[un]plug is desirable. This change adds one new sysfs interface (/sys/devices/system/memory/system_zone_details) which will fetch and dump this information. Example zonelist information from a KVM guest. [NODE (0)] ZONELIST_FALLBACK (0) (node 0) (zone DMA c00000000140c000) (1) (node 1) (zone DMA c000000100000000) (2) (node 2) (zone DMA c000000200000000) (3) (node 3) (zone DMA c000000300000000) ZONELIST_NOFALLBACK (0) (node 0) (zone DMA c00000000140c000) [NODE (1)] ZONELIST_FALLBACK (0) (node 1) (zone DMA c000000100000000) (1) (node 2) (zone DMA c000000200000000) (2) (node 3) (zone DMA c000000300000000) (3) (node 0) (zone DMA c00000000140c000) ZONELIST_NOFALLBACK (0) (node 1) (zone DMA c000000100000000) [NODE (2)] ZONELIST_FALLBACK (0) (node 2) (zone DMA c000000200000000) (1) (node 3) (zone DMA c000000300000000) (2) (node 0) (zone DMA c00000000140c000) (3) (node 1) (zone DMA c000000100000000) ZONELIST_NOFALLBACK (0) (node 2) (zone DMA c000000200000000) [NODE (3)] ZONELIST_FALLBACK (0) (node 3) (zone DMA c000000300000000) (1) (node 0) (zone DMA c00000000140c000) (2) (node 1) (zone DMA c000000100000000) (3) (node 2) (zone DMA c000000200000000) ZONELIST_NOFALLBACK (0) (node 3) (zone DMA c000000300000000) Signed-off-by: Anshuman Khandual --- Changes in V2: - Added more details into the commit message - Added sysfs interface file details into the commit message - Added ../ABI/testing/sysfs-system-zone-details file .../ABI/testing/sysfs-system-zone-details | 9 +++++ drivers/base/memory.c | 46 ++++++++++++++++++++++ 2 files changed, 55 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-system-zone-details diff --git a/Documentation/ABI/testing/sysfs-system-zone-details b/Documentation/ABI/testing/sysfs-system-zone-details new file mode 100644 index 0000000..9c13b2e --- /dev/null +++ b/Documentation/ABI/testing/sysfs-system-zone-details @@ -0,0 +1,9 @@ +What: /sys/devices/system/memory/system_zone_details +Date: Sep 2016 +KernelVersion: 4.8 +Contact: khandual@linux.vnet.ibm.com +Description: + This read only file dumps the zonelist and it's constituent + zones information for both ZONELIST_FALLBACK and ZONELIST_ + NOFALLBACK zonelists for each online node of the system at + any given point of time. diff --git a/drivers/base/memory.c b/drivers/base/memory.c index dc75de9..8c9330a 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -442,7 +442,52 @@ print_block_size(struct device *dev, struct device_attribute *attr, return sprintf(buf, "%lx\n", get_memory_block_size()); } +static ssize_t dump_zonelist(char *buf, struct zonelist *zonelist) +{ + unsigned int i; + ssize_t count = 0; + + for (i = 0; zonelist->_zonerefs[i].zone; i++) { + count += sprintf(buf + count, + "\t\t(%d) (node %d) (%-10s %lx)\n", i, + zonelist->_zonerefs[i].zone->zone_pgdat->node_id, + zone_names[zonelist->_zonerefs[i].zone_idx], + (unsigned long) zonelist->_zonerefs[i].zone); + } + return count; +} + +static ssize_t dump_zonelists(char *buf) +{ + struct zonelist *zonelist; + unsigned int node; + ssize_t count = 0; + + for_each_online_node(node) { + zonelist = &(NODE_DATA(node)-> + node_zonelists[ZONELIST_FALLBACK]); + count += sprintf(buf + count, "[NODE (%d)]\n", node); + count += sprintf(buf + count, "\tZONELIST_FALLBACK\n"); + count += dump_zonelist(buf + count, zonelist); + + zonelist = &(NODE_DATA(node)-> + node_zonelists[ZONELIST_NOFALLBACK]); + count += sprintf(buf + count, "\tZONELIST_NOFALLBACK\n"); + count += dump_zonelist(buf + count, zonelist); + } + return count; +} + +static ssize_t +print_system_zone_details(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return dump_zonelists(buf); +} + + static DEVICE_ATTR(block_size_bytes, 0444, print_block_size, NULL); +static DEVICE_ATTR(system_zone_details, 0444, print_system_zone_details, NULL); /* * Memory auto online policy. @@ -783,6 +828,7 @@ static struct attribute *memory_root_attrs[] = { #endif &dev_attr_block_size_bytes.attr, + &dev_attr_system_zone_details.attr, &dev_attr_auto_online_blocks.attr, NULL }; -- 2.1.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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