Commit 9442e81d authored by Davidlohr Bueso's avatar Davidlohr Bueso Committed by Greg Kroah-Hartman
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staging/wlan-ng, prism2usb: replace completion_bh tasklet with work 



Tasklets have long been deprecated as being too heavy on the system
by running in irq context - and this is not a performance critical
path. If a higher priority process wants to run, it must wait for
the tasklet to finish before doing so.

The completion_bh tasklet will now run in process context and have
further concurrency (tasklets being serialized among themselves),
but this is done holding the ctlxq.lock, so it should be fine.

Signed-off-by: default avatarDavidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20220411151620.129178-4-dave@stgolabs.net


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent cbe0f674

drivers/staging/wlan-ng/hfa384x.h

+1 −1
Original line number Diff line number Diff line
@@ -1228,7 +1228,7 @@ struct hfa384x { 
	struct timer_list throttle;



	struct work_struct reaper_bh;

	struct tasklet_struct completion_bh;

	struct work_struct completion_bh;



	struct work_struct usb_work;

drivers/staging/wlan-ng/hfa384x_usb.c

+11 −11
Original line number Diff line number Diff line
@@ -191,7 +191,7 @@ static void hfa384x_usbctlx_resptimerfn(struct timer_list *t); 


static void hfa384x_usb_throttlefn(struct timer_list *t);



static void hfa384x_usbctlx_completion_task(struct tasklet_struct *t);

static void hfa384x_usbctlx_completion_task(struct work_struct *work);



static void hfa384x_usbctlx_reaper_task(struct work_struct *work);
@@ -540,7 +540,7 @@ void hfa384x_create(struct hfa384x *hw, struct usb_device *usb) 
	skb_queue_head_init(&hw->authq);



	INIT_WORK(&hw->reaper_bh, hfa384x_usbctlx_reaper_task);

	tasklet_setup(&hw->completion_bh, hfa384x_usbctlx_completion_task);

	INIT_WORK(&hw->completion_bh, hfa384x_usbctlx_completion_task);

	INIT_WORK(&hw->link_bh, prism2sta_processing_defer);

	INIT_WORK(&hw->usb_work, hfa384x_usb_defer);
@@ -2585,10 +2585,10 @@ void hfa384x_tx_timeout(struct wlandevice *wlandev) 
/*----------------------------------------------------------------

 * hfa384x_usbctlx_reaper_task

 *

 * Deferred work to delete dead CTLX objects

 * Deferred work callback to delete dead CTLX objects

 *

 * Arguments:

 *	data	ptr to a struct hfa384x

 *	work	contains ptr to a struct hfa384x

 *

 * Returns:

 *
@@ -2618,21 +2618,21 @@ static void hfa384x_usbctlx_reaper_task(struct work_struct *work) 
/*----------------------------------------------------------------

 * hfa384x_usbctlx_completion_task

 *

 * Tasklet to call completion handlers for returned CTLXs

 * Deferred work callback to call completion handlers for returned CTLXs

 *

 * Arguments:

 *	data	ptr to struct hfa384x

 *	work	contains ptr to a struct hfa384x

 *

 * Returns:

 *	Nothing

 *

 * Call context:

 *	Interrupt

 *      Task

 *----------------------------------------------------------------

 */

static void hfa384x_usbctlx_completion_task(struct tasklet_struct *t)

static void hfa384x_usbctlx_completion_task(struct work_struct *work)

{

	struct hfa384x *hw = from_tasklet(hw, t, completion_bh);

	struct hfa384x *hw = container_of(work, struct hfa384x, reaper_bh);

	struct hfa384x_usbctlx *ctlx, *temp;

	unsigned long flags;
@@ -2743,7 +2743,7 @@ static int unlocked_usbctlx_cancel_async(struct hfa384x *hw, 
 * aren't active and the timers should have been stopped.

 *

 * The CTLX is migrated to the "completing" queue, and the completing

 * tasklet is scheduled.

 * work is scheduled.

 *

 * Arguments:

 *	hw		ptr to a struct hfa384x structure
@@ -2766,7 +2766,7 @@ static void unlocked_usbctlx_complete(struct hfa384x *hw, 
	 * queue.

	 */

	list_move_tail(&ctlx->list, &hw->ctlxq.completing);

	tasklet_schedule(&hw->completion_bh);

	schedule_work(&hw->completion_bh);



	switch (ctlx->state) {

	case CTLX_COMPLETE:

drivers/staging/wlan-ng/prism2usb.c

+3 −3
Original line number Diff line number Diff line
@@ -165,8 +165,8 @@ static void prism2sta_disconnect_usb(struct usb_interface *interface) 
		spin_unlock_irqrestore(&hw->ctlxq.lock, flags);



		/* There's no hardware to shutdown, but the driver

		 * might have some tasks or tasklets that must be

		 * stopped before we can tear everything down.

		 * might have some tasks that must be stopped before

		 * we can tear everything down.

		 */

		prism2sta_ifstate(wlandev, P80211ENUM_ifstate_disable);
@@ -181,7 +181,7 @@ static void prism2sta_disconnect_usb(struct usb_interface *interface) 
		usb_kill_urb(&hw->tx_urb);

		usb_kill_urb(&hw->ctlx_urb);



		tasklet_kill(&hw->completion_bh);

		cancel_work_sync(&hw->completion_bh);

		cancel_work_sync(&hw->reaper_bh);



		cancel_work_sync(&hw->link_bh);