kset: move /sys/slab to /sys/kernel/slab

/sys/kernel is where these things should go.
Also updated the documentation and tool that used this directory.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Documentation/vm/slabinfo.c

@@ -1021,7 +1021,7 @@ void read_slab_dir(void)
 	char *t;
 	int count;
 
-	if (chdir("/sys/slab"))
+	if (chdir("/sys/kernel/slab"))
 		fatal("SYSFS support for SLUB not active\n");
 
 	dir = opendir(".");

Documentation/vm/slub.txt

@@ -63,7 +63,7 @@ In case you forgot to enable debugging on the kernel command line: It is
 possible to enable debugging manually when the kernel is up. Look at the
 contents of:
 
-/sys/slab/<slab name>/
+/sys/kernel/slab/<slab name>/
 
 Look at the writable files. Writing 1 to them will enable the
 corresponding debug option. All options can be set on a slab that does

mm/slub.c

@@ -4091,7 +4091,8 @@ static int __init slab_sysfs_init(void)
 	struct kmem_cache *s;
 	int err;
 
-	slab_kset = kset_create_and_add("slab", &slab_uevent_ops, NULL);
+	slab_kset = kset_create_and_add("slab", &slab_uevent_ops,
+					&kernel_kset->kobj);
 	if (!slab_kset) {
 		printk(KERN_ERR "Cannot register slab subsystem.\n");
 		return -ENOSYS;