Re: btusb autosuspend and circular lock dep

Oliver Neukum
2009-08-24T13:59:58Z

Am Montag, 24. August 2009 10:20:46 schrieb Marcel Holtmann:
> Hi Oliver,
>
> > > I see. I removed that case and re-tested. The simple down, auto, up,
> > > down test worked fine. However, the down, up, wait, auto test failed.
> > > Logs of the success and the failure are attached.
> >
> > Very well, this version works for me.
>
> can you send a clean version so we can merge this into 2.6.32. This
> version still has the debug details in there. And please send it to the
> mailing list for reference.

Here it is again? Do you still want skip_waking to be replaced with skip ?

Regards
Oliver

Signed-off-by: Oliver Neukum <oliver@neukum.org>

--

--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -35,7 +35,7 @@
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

-#define VERSION "0.5"
+#define VERSION "0.6"

static int ignore_dga;
static int ignore_csr;
@@ -145,6 +145,7 @@ static struct usb_device_id blacklist_table[] = {
#define BTUSB_INTR_RUNNING 0
#define BTUSB_BULK_RUNNING 1
#define BTUSB_ISOC_RUNNING 2
+#define BTUSB_SUSPENDING 3

struct btusb_data {
struct hci_dev *hdev;
@@ -157,11 +158,15 @@ struct btusb_data {
unsigned long flags;

struct work_struct work;
+ struct work_struct waker;

struct usb_anchor tx_anchor;
struct usb_anchor intr_anchor;
struct usb_anchor bulk_anchor;
struct usb_anchor isoc_anchor;
+ struct usb_anchor deferred;
+ int tx_in_flight;
+ spinlock_t txlock;

struct usb_endpoint_descriptor *intr_ep;
struct usb_endpoint_descriptor *bulk_tx_ep;
@@ -174,8 +179,23 @@ struct btusb_data {
unsigned int sco_num;
int isoc_altsetting;
int suspend_count;
+ int did_iso_resume:1;
};

+static int inc_tx(struct btusb_data *data)
+{
+ unsigned long flags;
+ int rv;
+
+ spin_lock_irqsave(&data->txlock, flags);
+ rv = test_bit(BTUSB_SUSPENDING, &data->flags);
+ if (!rv)
+ data->tx_in_flight++;
+ spin_unlock_irqrestore(&data->txlock, flags);
+
+ return rv;
+}
+
static void btusb_intr_complete(struct urb *urb)
{
struct hci_dev *hdev = urb->context;
@@ -202,6 +222,7 @@ static void btusb_intr_complete(struct urb *urb)
if (!test_bit(BTUSB_INTR_RUNNING, &data->flags))
return;

+ usb_mark_last_busy(data->udev);
usb_anchor_urb(urb, &data->intr_anchor);

err = usb_submit_urb(urb, GFP_ATOMIC);
@@ -327,6 +348,7 @@ static int btusb_submit_bulk_urb(struct hci_dev *hdev, gfp_t mem_flags)

urb->transfer_flags |= URB_FREE_BUFFER;

+ usb_mark_last_busy(data->udev);
usb_anchor_urb(urb, &data->bulk_anchor);

err = usb_submit_urb(urb, mem_flags);
@@ -465,6 +487,33 @@ static void btusb_tx_complete(struct urb *urb)
{
struct sk_buff *skb = urb->context;
struct hci_dev *hdev = (struct hci_dev *) skb->dev;
+ struct btusb_data *data = hdev->driver_data;
+
+ BT_DBG("%s urb %p status %d count %d", hdev->name,
+ urb, urb->status, urb->actual_length);
+
+ if (!test_bit(HCI_RUNNING, &hdev->flags))
+ goto done;
+
+ if (!urb->status)
+ hdev->stat.byte_tx += urb->transfer_buffer_length;
+ else
+ hdev->stat.err_tx++;
+
+done:
+ spin_lock(&data->txlock);
+ data->tx_in_flight--;
+ spin_unlock(&data->txlock);
+
+ kfree(urb->setup_packet);
+
+ kfree_skb(skb);
+}
+
+static void btusb_isoc_tx_complete(struct urb *urb)
+{
+ struct sk_buff *skb = urb->context;
+ struct hci_dev *hdev = (struct hci_dev *) skb->dev;

BT_DBG("%s urb %p status %d count %d", hdev->name,
urb, urb->status, urb->actual_length);
@@ -490,11 +539,17 @@ static int btusb_open(struct hci_dev *hdev)

BT_DBG("%s", hdev->name);

+ err = usb_autopm_get_interface(data->intf);
+ if (err < 0)
+ return err;
+
+ data->intf->needs_remote_wakeup = 1;
+
if (test_and_set_bit(HCI_RUNNING, &hdev->flags))
- return 0;
+ goto done;

if (test_and_set_bit(BTUSB_INTR_RUNNING, &data->flags))
- return 0;
+ goto done;

err = btusb_submit_intr_urb(hdev, GFP_KERNEL);
if (err < 0)
@@ -509,17 +564,28 @@ static int btusb_open(struct hci_dev *hdev)
set_bit(BTUSB_BULK_RUNNING, &data->flags);
btusb_submit_bulk_urb(hdev, GFP_KERNEL);

+done:
+ usb_autopm_put_interface(data->intf);
return 0;

failed:
clear_bit(BTUSB_INTR_RUNNING, &data->flags);
clear_bit(HCI_RUNNING, &hdev->flags);
+ usb_autopm_put_interface(data->intf);
return err;
}

+static void btusb_stop_traffic(struct btusb_data *data)
+{
+ usb_kill_anchored_urbs(&data->intr_anchor);
+ usb_kill_anchored_urbs(&data->bulk_anchor);
+ usb_kill_anchored_urbs(&data->isoc_anchor);
+}
+
static int btusb_close(struct hci_dev *hdev)
{
struct btusb_data *data = hdev->driver_data;
+ int err;

BT_DBG("%s", hdev->name);

@@ -529,13 +595,16 @@ static int btusb_close(struct hci_dev *hdev)
cancel_work_sync(&data->work);

clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
- usb_kill_anchored_urbs(&data->isoc_anchor);
-
clear_bit(BTUSB_BULK_RUNNING, &data->flags);
- usb_kill_anchored_urbs(&data->bulk_anchor);
-
clear_bit(BTUSB_INTR_RUNNING, &data->flags);
- usb_kill_anchored_urbs(&data->intr_anchor);
+
+ btusb_stop_traffic(data);
+ err = usb_autopm_get_interface(data->intf);
+ if (err < 0)
+ return 0;
+
+ data->intf->needs_remote_wakeup = 0;
+ usb_autopm_put_interface(data->intf);

return 0;
}
@@ -622,7 +691,7 @@ static int btusb_send_frame(struct sk_buff *skb)
urb->dev = data->udev;
urb->pipe = pipe;
urb->context = skb;
- urb->complete = btusb_tx_complete;
+ urb->complete = btusb_isoc_tx_complete;
urb->interval = data->isoc_tx_ep->bInterval;

urb->transfer_flags = URB_ISO_ASAP;
@@ -633,12 +702,21 @@ static int btusb_send_frame(struct sk_buff *skb)
le16_to_cpu(data->isoc_tx_ep->wMaxPacketSize));

hdev->stat.sco_tx++;
- break;
+ goto skip_waking;

default:
return -EILSEQ;
}

+ err = inc_tx(data);
+ if (err) {
+ usb_anchor_urb(urb, &data->deferred);
+ schedule_work(&data->waker);
+ err = 0;
+ goto done;
+ }
+
+skip_waking:
usb_anchor_urb(urb, &data->tx_anchor);

err = usb_submit_urb(urb, GFP_ATOMIC);
@@ -646,10 +724,13 @@ static int btusb_send_frame(struct sk_buff *skb)
BT_ERR("%s urb %p submission failed", hdev->name, urb);
kfree(urb->setup_packet);
usb_unanchor_urb(urb);
+ } else {
+ usb_mark_last_busy(data->udev);
}

usb_free_urb(urb);

+done:
return err;
}

@@ -721,8 +802,19 @@ static void btusb_work(struct work_struct *work)
{
struct btusb_data *data = container_of(work, struct btusb_data, work);
struct hci_dev *hdev = data->hdev;
+ int err;

if (hdev->conn_hash.sco_num > 0) {
+ if (!data->did_iso_resume) {
+ err = usb_autopm_get_interface(data->isoc);
+ if (err < 0) {
+ clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
+ usb_kill_anchored_urbs(&data->isoc_anchor);
+ return;
+ }
+
+ data->did_iso_resume = 1;
+ }
if (data->isoc_altsetting != 2) {
clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
usb_kill_anchored_urbs(&data->isoc_anchor);
@@ -742,9 +834,25 @@ static void btusb_work(struct work_struct *work)
usb_kill_anchored_urbs(&data->isoc_anchor);

__set_isoc_interface(hdev, 0);
+ if (data->did_iso_resume) {
+ data->did_iso_resume = 0;
+ usb_autopm_put_interface(data->isoc);
+ }
}
}

+static void btusb_waker(struct work_struct *work)
+{
+ struct btusb_data *data = container_of(work, struct btusb_data, waker);
+ int err;
+
+ err = usb_autopm_get_interface(data->intf);
+ if (!err < 0)
+ return;
+
+ usb_autopm_put_interface(data->intf);
+}
+
static int btusb_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
@@ -814,11 +922,14 @@ static int btusb_probe(struct usb_interface *intf,
spin_lock_init(&data->lock);

INIT_WORK(&data->work, btusb_work);
+ INIT_WORK(&data->waker, btusb_waker);
+ spin_lock_init(&data->txlock);

init_usb_anchor(&data->tx_anchor);
init_usb_anchor(&data->intr_anchor);
init_usb_anchor(&data->bulk_anchor);
init_usb_anchor(&data->isoc_anchor);
+ init_usb_anchor(&data->deferred);

hdev = hci_alloc_dev();
if (!hdev) {
@@ -943,6 +1054,7 @@ static void btusb_disconnect(struct usb_interface *intf)
hci_free_dev(hdev);
}

+#ifdef CONFIG_PM
static int btusb_suspend(struct usb_interface *intf, pm_message_t message)
{
struct btusb_data *data = usb_get_intfdata(intf);
@@ -952,22 +1064,44 @@ static int btusb_suspend(struct usb_interface *intf, pm_message_t message)
if (data->suspend_count++)
return 0;

+ spin_lock_irq(&data->txlock);
+ if (!(interface_to_usbdev(intf)->auto_pm && data->tx_in_flight)) {
+ set_bit(BTUSB_SUSPENDING, &data->flags);
+ spin_unlock_irq(&data->txlock);
+ } else {
+ spin_unlock_irq(&data->txlock);
+ data->suspend_count--;
+ return -EBUSY;
+ }
+
cancel_work_sync(&data->work);

+ btusb_stop_traffic(data);
usb_kill_anchored_urbs(&data->tx_anchor);

- usb_kill_anchored_urbs(&data->isoc_anchor);
- usb_kill_anchored_urbs(&data->bulk_anchor);
- usb_kill_anchored_urbs(&data->intr_anchor);
-
return 0;
}

+static void play_deferred(struct btusb_data *data)
+{
+ struct urb *urb;
+ int err;
+
+ while ((urb = usb_get_from_anchor(&data->deferred))) {
+ err = usb_submit_urb(urb, GFP_ATOMIC);
+ if (err < 0)
+ break;
+
+ data->tx_in_flight++;
+ }
+ usb_scuttle_anchored_urbs(&data->deferred);
+}
+
static int btusb_resume(struct usb_interface *intf)
{
struct btusb_data *data = usb_get_intfdata(intf);
struct hci_dev *hdev = data->hdev;
- int err;
+ int err = 0;

BT_DBG("intf %p", intf);

@@ -975,13 +1109,13 @@ static int btusb_resume(struct usb_interface *intf)
return 0;

if (!test_bit(HCI_RUNNING, &hdev->flags))
- return 0;
+ goto done;

if (test_bit(BTUSB_INTR_RUNNING, &data->flags)) {
err = btusb_submit_intr_urb(hdev, GFP_NOIO);
if (err < 0) {
clear_bit(BTUSB_INTR_RUNNING, &data->flags);
- return err;
+ goto failed;
}
}

@@ -989,9 +1123,10 @@ static int btusb_resume(struct usb_interface *intf)
err = btusb_submit_bulk_urb(hdev, GFP_NOIO);
if (err < 0) {
clear_bit(BTUSB_BULK_RUNNING, &data->flags);
- return err;
- } else
+ goto failed;
+ } else {
btusb_submit_bulk_urb(hdev, GFP_NOIO);
+ }
}

if (test_bit(BTUSB_ISOC_RUNNING, &data->flags)) {
@@ -1001,16 +1136,35 @@ static int btusb_resume(struct usb_interface *intf)
btusb_submit_isoc_urb(hdev, GFP_NOIO);
}

+ spin_lock_irq(&data->txlock);
+ play_deferred(data);
+ clear_bit(BTUSB_SUSPENDING, &data->flags);
+ spin_unlock_irq(&data->txlock);
+ schedule_work(&data->work);
+
return 0;
+
+failed:
+ usb_scuttle_anchored_urbs(&data->deferred);
+done:
+ spin_lock_irq(&data->txlock);
+ clear_bit(BTUSB_SUSPENDING, &data->flags);
+ spin_unlock_irq(&data->txlock);
+
+ return err;
}
+#endif

static struct usb_driver btusb_driver = {
.name = "btusb",
.probe = btusb_probe,
.disconnect = btusb_disconnect,
+#ifdef CONFIG_PM
.suspend = btusb_suspend,
.resume = btusb_resume,
+#endif
.id_table = btusb_table,
+ .supports_autosuspend = 1,
};

static int __init btusb_init(void)