Commit f0325e38 authored by Tony Lindgren's avatar Tony Lindgren Committed by Kalle Valo
Browse files

wlcore: Use spin_trylock in wlcore_irq_locked() for running the queue 



We currently have a collection of flags and locking between the
threaded irq and tx work:

- wl->flags bitops
- wl->mutex
- wl->wl_lock spinlock

The bitops flags do not need a spinlock around them, and
wlcore_irq() already holds the mutex calling wlcore_irq_locked().
And we only need the spinlock to see if we need to run the queue
or not.

To simplify the locking, we can use spin_trylock and always run the
tx queue unless we know there's nothing to do.

Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarKalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200702162951.45392-3-tony@atomide.com
parent eb215c33

drivers/net/wireless/ti/wlcore/main.c

+13 −9
Original line number Diff line number Diff line
@@ -521,6 +521,7 @@ static int wlcore_irq_locked(struct wl1271 *wl) 
	int ret = 0;

	u32 intr;

	int loopcount = WL1271_IRQ_MAX_LOOPS;

	bool run_tx_queue = true;

	bool done = false;

	unsigned int defer_count;

	unsigned long flags;
@@ -586,19 +587,22 @@ static int wlcore_irq_locked(struct wl1271 *wl) 
				goto err_ret;



			/* Check if any tx blocks were freed */

			spin_lock_irqsave(&wl->wl_lock, flags);

			if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags) &&

			    wl1271_tx_total_queue_count(wl) > 0) {

			if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags)) {

				if (spin_trylock_irqsave(&wl->wl_lock, flags)) {

					if (!wl1271_tx_total_queue_count(wl))

						run_tx_queue = false;

					spin_unlock_irqrestore(&wl->wl_lock, flags);

				}



				/*

				 * In order to avoid starvation of the TX path,

				 * call the work function directly.

				 */

				if (run_tx_queue) {

					ret = wlcore_tx_work_locked(wl);

					if (ret < 0)

						goto err_ret;

			} else {

				spin_unlock_irqrestore(&wl->wl_lock, flags);

				}

			}



			/* check for tx results */