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: Tony Lindgren <tony@atomide.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200702162951.45392-3-tony@atomide.com
This commit is contained in:
Tony Lindgren 2020-07-02 09:29:49 -07:00 committed by Kalle Valo
parent eb215c33f3
commit f0325e38ab

View file

@ -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) {
spin_unlock_irqrestore(&wl->wl_lock, flags);
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.
*/
ret = wlcore_tx_work_locked(wl);
if (ret < 0)
goto err_ret;
} else {
spin_unlock_irqrestore(&wl->wl_lock, flags);
if (run_tx_queue) {
ret = wlcore_tx_work_locked(wl);
if (ret < 0)
goto err_ret;
}
}
/* check for tx results */