Commit 35fba0f0 authored by Tony Lindgren's avatar Tony Lindgren Committed by Kalle Valo
Browse files

wlcore: Use spin_trylock in wlcore_irq() to see if we need to queue tx 



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 we only need
the spinlock to see if we need to queue tx work or not. And wlcore_irq()
holds the mutex.

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

Let's also update the comment a bit while at it.

Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarKalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200702162951.45392-4-tony@atomide.com
parent f0325e38

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

+11 −6
Original line number Diff line number Diff line
@@ -652,6 +652,7 @@ static irqreturn_t wlcore_irq(int irq, void *cookie) 
	int ret;

	unsigned long flags;

	struct wl1271 *wl = cookie;

	bool queue_tx_work = true;



	set_bit(WL1271_FLAG_IRQ_RUNNING, &wl->flags);
@@ -684,13 +685,17 @@ static irqreturn_t wlcore_irq(int irq, void *cookie) 
	if (ret)

		wl12xx_queue_recovery_work(wl);



	spin_lock_irqsave(&wl->wl_lock, flags);

	/* In case TX was not handled here, queue TX work */

	/* In case TX was not handled in wlcore_irq_locked(), queue TX work */

	clear_bit(WL1271_FLAG_TX_PENDING, &wl->flags);

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

	    wl1271_tx_total_queue_count(wl) > 0)

		ieee80211_queue_work(wl->hw, &wl->tx_work);

	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))

				queue_tx_work = false;

			spin_unlock_irqrestore(&wl->wl_lock, flags);

		}

		if (queue_tx_work)

			ieee80211_queue_work(wl->hw, &wl->tx_work);

	}



	mutex_unlock(&wl->mutex);