[PATCH] Read cpumasks every time when exporting through sysfs

[PATCH] Read cpumasks every time when exporting through sysfs

[Rusty Russell]

Name: Read cpumasks every time when exporting through sysfs
Status: Booted on 2.6.7-rc2-bk7
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Paul Jackson points out that the sysfs code saves a node's cpumask in
the sysfs node, although it can change with CPU hotplug.  Don't do
this.

diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .4860-linux-2.6.7-rc2-bk7/drivers/base/node.c .4860-linux-2.6.7-rc2-bk7.updated/drivers/base/node.c
--- .4860-linux-2.6.7-rc2-bk7/drivers/base/node.c	2004-06-07 07:47:33.000000000 +1000
+++ .4860-linux-2.6.7-rc2-bk7.updated/drivers/base/node.c	2004-06-07 12:26:16.000000000 +1000
@@ -18,7 +18,7 @@ static struct sysdev_class node_class = 
 static ssize_t node_read_cpumap(struct sys_device * dev, char * buf)
 {
 	struct node *node_dev = to_node(dev);
-	cpumask_t mask = node_dev->cpumap;
+	cpumask_t mask = node_to_cpumask(node_dev->sysdev.id);
 	int len;
 
 	/* 2004/06/03: buf currently PAGE_SIZE, need > 1 char per 4 bits. */
@@ -116,7 +116,6 @@ int __init register_node(struct node *no
 {
 	int error;
 
-	node->cpumap = node_to_cpumask(num);
 	node->sysdev.id = num;
 	node->sysdev.cls = &node_class;
 	error = sysdev_register(&node->sysdev);
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .4860-linux-2.6.7-rc2-bk7/include/linux/node.h .4860-linux-2.6.7-rc2-bk7.updated/include/linux/node.h
--- .4860-linux-2.6.7-rc2-bk7/include/linux/node.h	2003-09-22 10:27:37.000000000 +1000
+++ .4860-linux-2.6.7-rc2-bk7.updated/include/linux/node.h	2004-06-07 12:24:47.000000000 +1000
@@ -23,7 +23,6 @@
 #include <linux/cpumask.h>
 
 struct node {
-	cpumask_t cpumap;	/* Bitmap of CPUs on the Node */
 	struct sys_device	sysdev;
 };
 

-- 
Anyone who quotes me in their signature is an idiot -- Rusty Russell

Re: [PATCH] Read cpumasks every time when exporting through sysfs

[Paul Jackson]

Rusty wrote:
> Read cpumasks every time when exporting through sysfs

Thanks, Rusty.

-- 
                          I won't rest till it's the best ...
                          Programmer, Linux Scalability
                          Paul Jackson <pj@sgi.com> 1.650.933.1373