mm: add node states sysfs class attributeS
Add a per node state sysfs class attribute file to /sys/devices/system/node
to display node state masks.
E.g., on a 4-cell HP ia64 NUMA platform, we have 5 nodes: 4 representing
the actual hardware cells and one memory-only pseudo-node representing a
small amount [512MB] of "hardware interleaved" memory. With this patch, in
/sys/devices/system/node we see:
#ls -1F /sys/devices/system/node
has_cpu
has_normal_memory
node0/
node1/
node2/
node3/
node4/
online
possible
#cat /sys/devices/system/node/possible
0-255
#cat /sys/devices/system/node/online
0-4
#cat /sys/devices/system/node/has_normal_memory
0-4
#cat /sys/devices/system/node/has_cpu
0-3
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/base/node.c b/drivers/base/node.c
index cae346e..88eeed7 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -12,6 +12,7 @@
#include <linux/topology.h>
#include <linux/nodemask.h>
#include <linux/cpu.h>
+#include <linux/device.h>
static struct sysdev_class node_class = {
set_kset_name("node"),
@@ -232,8 +233,96 @@
unregister_node(&node_devices[nid]);
}
+/*
+ * node states attributes
+ */
+
+static ssize_t print_nodes_state(enum node_states state, char *buf)
+{
+ int n;
+
+ n = nodelist_scnprintf(buf, PAGE_SIZE, node_states[state]);
+ if (n > 0 && PAGE_SIZE > n + 1) {
+ *(buf + n++) = '\n';
+ *(buf + n++) = '\0';
+ }
+ return n;
+}
+
+static ssize_t print_nodes_possible(struct sysdev_class *class, char *buf)
+{
+ return print_nodes_state(N_POSSIBLE, buf);
+}
+
+static ssize_t print_nodes_online(struct sysdev_class *class, char *buf)
+{
+ return print_nodes_state(N_ONLINE, buf);
+}
+
+static ssize_t print_nodes_has_normal_memory(struct sysdev_class *class,
+ char *buf)
+{
+ return print_nodes_state(N_NORMAL_MEMORY, buf);
+}
+
+static ssize_t print_nodes_has_cpu(struct sysdev_class *class, char *buf)
+{
+ return print_nodes_state(N_CPU, buf);
+}
+
+static SYSDEV_CLASS_ATTR(possible, 0444, print_nodes_possible, NULL);
+static SYSDEV_CLASS_ATTR(online, 0444, print_nodes_online, NULL);
+static SYSDEV_CLASS_ATTR(has_normal_memory, 0444, print_nodes_has_normal_memory,
+ NULL);
+static SYSDEV_CLASS_ATTR(has_cpu, 0444, print_nodes_has_cpu, NULL);
+
+#ifdef CONFIG_HIGHMEM
+static ssize_t print_nodes_has_high_memory(struct sysdev_class *class,
+ char *buf)
+{
+ return print_nodes_state(N_HIGH_MEMORY, buf);
+}
+
+static SYSDEV_CLASS_ATTR(has_high_memory, 0444, print_nodes_has_high_memory,
+ NULL);
+#endif
+
+struct sysdev_class_attribute *node_state_attr[] = {
+ &attr_possible,
+ &attr_online,
+ &attr_has_normal_memory,
+#ifdef CONFIG_HIGHMEM
+ &attr_has_high_memory,
+#endif
+ &attr_has_cpu,
+};
+
+static int node_states_init(void)
+{
+ int i;
+ int err = 0;
+
+ for (i = 0; i < NR_NODE_STATES; i++) {
+ int ret;
+ ret = sysdev_class_create_file(&node_class, node_state_attr[i]);
+ if (!err)
+ err = ret;
+ }
+ return err;
+}
+
static int __init register_node_type(void)
{
- return sysdev_class_register(&node_class);
+ int ret;
+
+ ret = sysdev_class_register(&node_class);
+ if (!ret)
+ ret = node_states_init();
+
+ /*
+ * Note: we're not going to unregister the node class if we fail
+ * to register the node state class attribute files.
+ */
+ return ret;
}
postcore_initcall(register_node_type);