Hi Luiz,
> This makes btusb to queue ACL and events during a polling interval
> by using of a delayed work, with the interval working as a time window
> where frames received from different endpoints are considered to be
> arrived at same time and then attempt to resolve potential conflics by
> processing the events ahead of ACL packets.
>
> It worth noting though that priorizing events over ACL data may result
> in inverting the order compared to how they appeared over the air, for
> instance there may be packets received before a disconnect event that
> will be discarded and unencrypted packets received before encryption
> change which would considered encrypted, because of these potential
> changes on the order the support for queuing during the polling
> interval is not enabled by default so it requires setting
> force_poll_sync debugfs while the adapter is down.
>
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
> ---
> v2: Check for intr_interval instead of enable_poll_sync when dispatching
> since the former can only be changed on open/resume.
> v3: Change the way the feature is enabled from module parameter to debugfs
> entry and rename it from enable_poll_sync to force_poll_sync.
>
> drivers/bluetooth/btusb.c | 125 ++++++++++++++++++++++++++++++++++++--
> 1 file changed, 120 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index ab169fc673ea..9b3cadb33fcb 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -16,6 +16,7 @@
> #include <linux/of_irq.h>
> #include <linux/suspend.h>
> #include <linux/gpio/consumer.h>
> +#include <linux/debugfs.h>
> #include <asm/unaligned.h>
>
> #include <net/bluetooth/bluetooth.h>
> @@ -31,7 +32,6 @@
> static bool disable_scofix;
> static bool force_scofix;
> static bool enable_autosuspend = IS_ENABLED(CONFIG_BT_HCIBTUSB_AUTOSUSPEND);
> -
> static bool reset = true;
>
> static struct usb_driver btusb_driver;
> @@ -558,8 +558,13 @@ struct btusb_data {
>
> unsigned long flags;
>
> - struct work_struct work;
> - struct work_struct waker;
> + bool poll_sync;
> + int intr_interval;
> + struct work_struct work;
> + struct work_struct waker;
> + struct delayed_work rx_work;
> +
> + struct sk_buff_head acl_q;
>
> struct usb_anchor deferred;
> struct usb_anchor tx_anchor;
> @@ -724,6 +729,15 @@ static inline void btusb_free_frags(struct btusb_data *data)
> spin_unlock_irqrestore(&data->rxlock, flags);
> }
>
> +static int btusb_recv_event(struct btusb_data *data, struct sk_buff *skb)
> +{
> + if (data->intr_interval)
enclose in {
> + /* Trigger dequeue immediatelly if an event is received */
> + schedule_delayed_work(&data->rx_work, 0);
} this please.
> +
> + return data->recv_event(data->hdev, skb);
> +}
> +
> static int btusb_recv_intr(struct btusb_data *data, void *buffer, int count)
> {
> struct sk_buff *skb;
> @@ -769,7 +783,7 @@ static int btusb_recv_intr(struct btusb_data *data, void *buffer, int count)
>
> if (!hci_skb_expect(skb)) {
> /* Complete frame */
> - data->recv_event(data->hdev, skb);
> + btusb_recv_event(data, skb);
> skb = NULL;
> }
> }
> @@ -780,6 +794,18 @@ static int btusb_recv_intr(struct btusb_data *data, void *buffer, int count)
> return err;
> }
>
> +static int btusb_recv_acl(struct btusb_data *data, struct sk_buff *skb)
> +{
Add a comment above here.
> + if (!data->intr_interval)
> + return data->recv_acl(data->hdev, skb);
> +
> + skb_queue_tail(&data->acl_q, skb);
> +
Skip this empty line.
> + schedule_delayed_work(&data->rx_work, data->intr_interval);
> +
> + return 0;
> +}
> +
> static int btusb_recv_bulk(struct btusb_data *data, void *buffer, int count)
> {
> struct sk_buff *skb;
> @@ -827,7 +853,7 @@ static int btusb_recv_bulk(struct btusb_data *data, void *buffer, int count)
>
> if (!hci_skb_expect(skb)) {
> /* Complete frame */
> - data->recv_acl(data->hdev, skb);
> + btusb_recv_acl(data, skb);
> skb = NULL;
> }
> }
> @@ -979,6 +1005,27 @@ static int btusb_submit_intr_urb(struct hci_dev *hdev, gfp_t mem_flags)
> usb_unanchor_urb(urb);
> }
>
> + /* Only initialize intr_interval if URB poll sync is enabled */
> + if (!data->poll_sync)
> + goto done;
> +
> + /* The units are frames (milliseconds) for full and low speed devices,
> + * and microframes (1/8 millisecond) for highspeed and SuperSpeed
> + * devices.
> + *
> + * This is done once on open/resume so it shouldn't change even if
> + * enable_poll_sync changes.
> + */
> + switch (urb->dev->speed) {
> + case USB_SPEED_SUPER_PLUS:
> + case USB_SPEED_SUPER: /* units are 125us */
> + data->intr_interval = usecs_to_jiffies(urb->interval * 125);
> + break;
> + default:
> + data->intr_interval = msecs_to_jiffies(urb->interval);
Add break here.
> + }
> +
> +done:
> usb_free_urb(urb);
>
> return err;
> @@ -1438,9 +1485,12 @@ static int btusb_close(struct hci_dev *hdev)
>
> BT_DBG("%s", hdev->name);
>
> + cancel_delayed_work(&data->rx_work);
> cancel_work_sync(&data->work);
> cancel_work_sync(&data->waker);
>
> + skb_queue_purge(&data->acl_q);
> +
> clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
> clear_bit(BTUSB_BULK_RUNNING, &data->flags);
> clear_bit(BTUSB_INTR_RUNNING, &data->flags);
> @@ -1472,6 +1522,10 @@ static int btusb_flush(struct hci_dev *hdev)
>
> BT_DBG("%s", hdev->name);
>
> + cancel_delayed_work(&data->rx_work);
> +
> + skb_queue_purge(&data->acl_q);
> +
> usb_kill_anchored_urbs(&data->tx_anchor);
> btusb_free_frags(data);
>
> @@ -1835,6 +1889,17 @@ static void btusb_waker(struct work_struct *work)
> usb_autopm_put_interface(data->intf);
> }
>
> +static void btusb_rx_work(struct work_struct *work)
> +{
> + struct btusb_data *data = container_of(work, struct btusb_data,
> + rx_work.work);
> + struct sk_buff *skb;
> +
> + /* Dequeue ACL data received during the interval */
> + while ((skb = skb_dequeue(&data->acl_q)))
> + data->recv_acl(data->hdev, skb);
> +}
> +
> static int btusb_setup_bcm92035(struct hci_dev *hdev)
> {
> struct sk_buff *skb;
> @@ -3392,6 +3457,49 @@ static int btusb_shutdown_qca(struct hci_dev *hdev)
> return 0;
> }
>
> +static ssize_t force_poll_sync_read(struct file *file, char __user *user_buf,
> + size_t count, loff_t *ppos)
> +{
> + struct btusb_data *data = file->private_data;
> + char buf[3];
> +
> + buf[0] = data->poll_sync ? 'Y' : 'N';
> + buf[1] = '\n';
> + buf[2] = '\0';
> + return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
> +}
> +
> +static ssize_t force_poll_sync_write(struct file *file,
> + const char __user *user_buf,
> + size_t count, loff_t *ppos)
> +{
> + struct btusb_data *data = file->private_data;
> + bool enable;
> + int err;
> +
> + err = kstrtobool_from_user(user_buf, count, &enable);
> + if (err)
> + return err;
> +
> + /* Only allow changes while the adapter is down */
> + if (test_bit(HCI_UP, &data->hdev->flags))
> + return -EPERM;
> +
> + if (data->poll_sync == enable)
> + return -EALREADY;
> +
> + data->poll_sync = enable;
> +
> + return count;
> +}
> +
> +static const struct file_operations force_poll_sync_fops = {
> + .open = simple_open,
> + .read = force_poll_sync_read,
> + .write = force_poll_sync_write,
> + .llseek = default_llseek,
> +};
> +
> static int btusb_probe(struct usb_interface *intf,
> const struct usb_device_id *id)
> {
> @@ -3475,6 +3583,10 @@ static int btusb_probe(struct usb_interface *intf,
>
> INIT_WORK(&data->work, btusb_work);
> INIT_WORK(&data->waker, btusb_waker);
> + INIT_DELAYED_WORK(&data->rx_work, btusb_rx_work);
> +
> + skb_queue_head_init(&data->acl_q);
> +
> init_usb_anchor(&data->deferred);
> init_usb_anchor(&data->tx_anchor);
> spin_lock_init(&data->txlock);
> @@ -3740,6 +3852,9 @@ static int btusb_probe(struct usb_interface *intf,
>
> usb_set_intfdata(intf, data);
>
> + debugfs_create_file("force_poll_sync", 0644, hdev->debugfs, data,
> + &force_poll_sync_fops);
> +
> return 0;
So besides cosmetic changes, looks good.
Regards
Marcel
