Greg KH
2005-06-21T02:30:32Z

[PATCH] Use a klist for device child lists.

- Use klist iterator in device_for_each_child(), making it safe to use for
removing devices.
- Remove unused list_to_dev() function.
- Kills all usage of devices_subsys.rwsem.

Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
commit 36239577cfb6b9a7c111209536b54200b0252ebf
tree f8fa5034fbb31d273d0889119cbc20e4c4b0c983
parent 9a881f166f473373589ce6f3fdc47b44a1450e2d
author mochel@digitalimplant.org <mochel@digitalimplant.org> Thu, 24 Mar 2005 19:08:30 -0800
committer Greg Kroah-Hartman <gregkh@suse.de> Mon, 20 Jun 2005 15:15:23 -0700

drivers/base/core.c | 30 +++++++++++++++---------------
include/linux/device.h | 10 ++--------
2 files changed, 17 insertions(+), 23 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -207,8 +207,7 @@ void device_initialize(struct device *de
{
kobj_set_kset_s(dev, devices_subsys);
kobject_init(&dev->kobj);
- INIT_LIST_HEAD(&dev->node);
- INIT_LIST_HEAD(&dev->children);
+ klist_init(&dev->klist_children);
INIT_LIST_HEAD(&dev->dma_pools);
init_MUTEX(&dev->sem);
}
@@ -249,10 +248,8 @@ int device_add(struct device *dev)
goto PMError;
if ((error = bus_add_device(dev)))
goto BusError;
- down_write(&devices_subsys.rwsem);
if (parent)
- list_add_tail(&dev->node, &parent->children);
- up_write(&devices_subsys.rwsem);
+ klist_add_tail(&parent->klist_children, &dev->knode_parent);

/* notify platform of device entry */
if (platform_notify)
@@ -335,10 +332,8 @@ void device_del(struct device * dev)
{
struct device * parent = dev->parent;

- down_write(&devices_subsys.rwsem);
if (parent)
- list_del_init(&dev->node);
- up_write(&devices_subsys.rwsem);
+ klist_remove(&dev->knode_parent);

/* Notify the platform of the removal, in case they
* need to do anything...
@@ -372,6 +367,12 @@ void device_unregister(struct device * d
}

+static struct device * next_device(struct klist_iter * i)
+{
+ struct klist_node * n = klist_next(i);
+ return n ? container_of(n, struct device, knode_parent) : NULL;
+}
+
/**
* device_for_each_child - device child iterator.
* @dev: parent struct device.
@@ -384,18 +385,17 @@ void device_unregister(struct device * d
* We check the return of @fn each time. If it returns anything
* other than 0, we break out and return that value.
*/
-int device_for_each_child(struct device * dev, void * data,
+int device_for_each_child(struct device * parent, void * data,
int (*fn)(struct device *, void *))
{
+ struct klist_iter i;
struct device * child;
int error = 0;

- down_read(&devices_subsys.rwsem);
- list_for_each_entry(child, &dev->children, node) {
- if((error = fn(child, data)))
- break;
- }
- up_read(&devices_subsys.rwsem);
+ klist_iter_init(&parent->klist_children, &i);
+ while ((child = next_device(&i)) && !error)
+ error = fn(child, data);
+ klist_iter_exit(&i);
return error;
}

diff --git a/include/linux/device.h b/include/linux/device.h
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -262,8 +262,8 @@ extern void class_device_destroy(struct

struct device {
- struct list_head node; /* node in sibling list */
- struct list_head children;
+ struct klist klist_children;
+ struct klist_node knode_parent; /* node in sibling list */
struct klist_node knode_driver;
struct klist_node knode_bus;
struct device * parent;
@@ -298,12 +298,6 @@ struct device {
void (*release)(struct device * dev);
};

-static inline struct device *
-list_to_dev(struct list_head *node)
-{
- return list_entry(node, struct device, node);
-}
-
static inline void *
dev_get_drvdata (struct device *dev)
{