[RFC/PATCH 2/4] drivers/base/node.c changes for dynamic cpu registration

Nathan Lynch
2004-10-24T09:45:33Z

Register numa node system devices in the core code instead of leaving
it to the architecture. Add an array of MAX_NUMNODES node devices and
register those which are online at boot. Create sysfs symlinks to
each node's cpu devices.

Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>

---

diff -puN drivers/base/node.c~move-node-sysdev-registration-to-core drivers/base/node.c
--- 2.6.10-rc1/drivers/base/node.c~move-node-sysdev-registration-to-core 2004-10-24 03:52:53.000000000 -0500
+++ 2.6.10-rc1-nathanl/drivers/base/node.c 2004-10-24 03:52:53.000000000 -0500
@@ -9,7 +9,9 @@
#include <linux/node.h>
#include <linux/hugetlb.h>
#include <linux/cpumask.h>
+#include <linux/nodemask.h>
#include <linux/topology.h>
+#include <linux/cpu.h>

static struct sysdev_class node_class = {
set_kset_name("node"),
@@ -133,9 +135,65 @@ int __init register_node(struct node *no
return error;
}

+static struct node *node_devices;
+
+static int node_cpu_add_dev (struct sys_device * sys_dev)
+{
+ unsigned int cpu = sys_dev->id;
+ int ret, node = cpu_to_node(cpu);
+
+ ret = sysfs_create_link(&node_devices[node].sysdev.kobj,
+ &sys_dev->kobj,
+ kobject_name(&sys_dev->kobj));
+ return ret;
+}
+
+static int node_cpu_remove_dev (struct sys_device * sys_dev)
+{
+ unsigned int cpu = sys_dev->id;
+ int node = cpu_to_node(cpu);
+
+ sysfs_remove_link(&node_devices[node].sysdev.kobj,
+ kobject_name(&sys_dev->kobj));
+ return 0;
+
+}
+
+/* Methods for notifying us when cpus are added and removed */
+static struct sysdev_driver node_cpu_sysdev_driver = {
+ .add = node_cpu_add_dev,
+ .remove = node_cpu_remove_dev,
+};

int __init register_node_type(void)
{
- return sysdev_class_register(&node_class);
+ int i, ret = 0;
+ size_t size = sizeof(*node_devices) * num_online_nodes();
+
+ sysdev_class_register(&node_class);
+
+ node_devices = kmalloc(size, GFP_KERNEL);
+ if (!node_devices)
+ return -ENOMEM;
+
+ memset(node_devices, 0, size);
+
+ for_each_online_node(i) {
+ int pnum = parent_node(i);
+ struct node *parent = NULL;
+
+ if (pnum != i)
+ parent = &node_devices[pnum];
+
+ ret = register_node(&node_devices[i], i, parent);
+
+ if (ret)
+ goto out;
+ }
+
+ ret = sysdev_driver_register(&cpu_sysdev_class,
+ &node_cpu_sysdev_driver);
+out:
+ return ret;
}
postcore_initcall(register_node_type);

_