Re: [PATCH retry] bluetooth : add conn add/del workqueues to avoid connection fail

Dave Young
2008-02-01T01:18:24Z

On Thu, Jan 31, 2008 at 02:09:30PM +0100, Jens Axboe wrote:
> On Wed, Jan 30 2008, Dave Young wrote:
> >
> > The bluetooth hci_conn sysfs add/del executed in the default workqueue.
> > If the del_conn is executed after the new add_conn with same target,
> > add_conn will failed with warning of "same kobject name".
> >
> > Here add btaddconn & btdelconn workqueues,
> > flush the btdelconn workqueue in the add_conn function to avoid the issue.
> >
> > Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
> >
> > ---
> > diff -upr a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
> > --- a/net/bluetooth/hci_sysfs.c 2008-01-30 10:14:27.000000000 +0800
> > +++ b/net/bluetooth/hci_sysfs.c 2008-01-30 10:14:14.000000000 +0800
> > @@ -12,6 +12,8 @@
> > #undef BT_DBG
> > #define BT_DBG(D...)
> > #endif
> > +static struct workqueue_struct *btaddconn;
> > +static struct workqueue_struct *btdelconn;
> >
> > static inline char *typetostr(int type)
> > {
> > @@ -279,6 +281,7 @@ static void add_conn(struct work_struct
> > struct hci_conn *conn = container_of(work, struct hci_conn, work);
> > int i;
> >
> > + flush_workqueue(btdelconn);
> > if (device_add(&conn->dev) < 0) {
> > BT_ERR("Failed to register connection device");
> > return;
> > @@ -313,6 +316,7 @@ void hci_conn_add_sysfs(struct hci_conn
> >
> > INIT_WORK(&conn->work, add_conn);
> >
> > + queue_work(btaddconn, &conn->work);
> > schedule_work(&conn->work);
> > }
>
> So you queue &conn->work on both btaddconn and keventd_wq?

My fault. Thanks for pointing out.

new patch as following (some fixes according to marcel's style as well)

---
[PATCH] bluetooth : add conn add/del workqueues to avoid connection fail

The bluetooth hci conn sysfs add/del executed in the default workqueue.
If the conn del function is executed after the new conn add function
with same bluetooth target address, the connection add will failed
and will warn about same kobject name.

Here add btaddconn & btdelconn workqueues,
flush the btdelconn workqueue in the add_conn function to avoid the issue.

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>

---
net/bluetooth/hci_sysfs.c | 52 ++++++++++++++++++++++++++++++++++++----------
1 file changed, 41 insertions(+), 11 deletions(-)

diff -upr a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
--- a/net/bluetooth/hci_sysfs.c 2008-02-01 09:18:40.000000000 +0800
+++ b/net/bluetooth/hci_sysfs.c 2008-02-01 09:18:40.000000000 +0800
@@ -12,6 +12,8 @@
#undef BT_DBG
#define BT_DBG(D...)
#endif
+static struct workqueue_struct *btaddconn;
+static struct workqueue_struct *btdelconn;

static inline char *typetostr(int type)
{
@@ -279,6 +281,8 @@ static void add_conn(struct work_struct
struct hci_conn *conn = container_of(work, struct hci_conn, work);
int i;

+ flush_workqueue(btdelconn);
+
if (device_add(&conn->dev) < 0) {
BT_ERR("Failed to register connection device");
return;
@@ -313,7 +317,7 @@ void hci_conn_add_sysfs(struct hci_conn

INIT_WORK(&conn->work, add_conn);

- schedule_work(&conn->work);
+ queue_work(btaddconn, &conn->work);
}

static int __match_tty(struct device *dev, void *data)
@@ -349,7 +353,7 @@ void hci_conn_del_sysfs(struct hci_conn

INIT_WORK(&conn->work, del_conn);

- schedule_work(&conn->work);
+ queue_work(btdelconn, &conn->work);
}

int hci_register_sysfs(struct hci_dev *hdev)
@@ -398,28 +402,54 @@ int __init bt_sysfs_init(void)
{
int err;

+ btaddconn = create_singlethread_workqueue("btaddconn");
+ if (!btaddconn) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ btdelconn = create_singlethread_workqueue("btdelconn");
+ if (!btdelconn) {
+ err = -ENOMEM;
+ goto out_del;
+ }
+
bt_platform = platform_device_register_simple("bluetooth", -1, NULL, 0);
- if (IS_ERR(bt_platform))
- return PTR_ERR(bt_platform);
+ if (IS_ERR(bt_platform)) {
+ err = PTR_ERR(bt_platform);
+ goto out_platform;
+ }

err = bus_register(&bt_bus);
- if (err < 0) {
- platform_device_unregister(bt_platform);
- return err;
- }
+ if (err < 0)
+ goto out_bus;

bt_class = class_create(THIS_MODULE, "bluetooth");
if (IS_ERR(bt_class)) {
- bus_unregister(&bt_bus);
- platform_device_unregister(bt_platform);
- return PTR_ERR(bt_class);
+ err = PTR_ERR(bt_class);
+ goto out_class;
}

return 0;
+
+out_class:
+ bus_unregister(&bt_bus);
+out_bus:
+ platform_device_unregister(bt_platform);
+out_platform:
+ destroy_workqueue(btdelconn);
+out_del:
+ destroy_workqueue(btaddconn);
+out:
+ return err;
}

void bt_sysfs_cleanup(void)
{
+ destroy_workqueue(btaddconn);
+
+ destroy_workqueue(btdelconn);
+
class_destroy(bt_class);

bus_unregister(&bt_bus);