class: add lockdep infrastructure
This adds the infrastructure to properly handle lockdep issues when the
internal class semaphore is changed to a mutex.
Matthew wrote the original patch, and Greg fixed it up to work properly
with the class_create() function.
From: Matthew Wilcox <matthew@wil.cx>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/include/linux/device.h b/include/linux/device.h
index b055608..0e1d24c 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -16,6 +16,7 @@
#include <linux/kobject.h>
#include <linux/klist.h>
#include <linux/list.h>
+#include <linux/lockdep.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/module.h>
@@ -205,8 +206,18 @@
extern struct kobject *sysfs_dev_block_kobj;
extern struct kobject *sysfs_dev_char_kobj;
-extern int __must_check class_register(struct class *class);
+extern int __must_check __class_register(struct class *class,
+ struct lock_class_key *key);
extern void class_unregister(struct class *class);
+
+/* This is a #define to keep the compiler from merging different
+ * instances of the __key variable */
+#define class_register(class) \
+({ \
+ static struct lock_class_key __key; \
+ __class_register(class, &__key); \
+})
+
extern int class_for_each_device(struct class *class, struct device *start,
void *data,
int (*fn)(struct device *dev, void *data));
@@ -239,9 +250,19 @@
extern int __must_check class_interface_register(struct class_interface *);
extern void class_interface_unregister(struct class_interface *);
-extern struct class *class_create(struct module *owner, const char *name);
+extern struct class * __must_check __class_create(struct module *owner,
+ const char *name,
+ struct lock_class_key *key);
extern void class_destroy(struct class *cls);
+/* This is a #define to keep the compiler from merging different
+ * instances of the __key variable */
+#define class_create(owner, name) \
+({ \
+ static struct lock_class_key __key; \
+ __class_create(owner, name, &__key); \
+})
+
/*
* The type of device, "struct device" is embedded in. A class
* or bus can contain devices of different types