From f0325e38ab39c2e270770b72c79795772ac3b49e Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Thu, 2 Jul 2020 09:29:49 -0700 Subject: [PATCH] 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 Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20200702162951.45392-3-tony@atomide.com --- drivers/net/wireless/ti/wlcore/main.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/net/wireless/ti/wlcore/main.c b/drivers/net/wireless/ti/wlcore/main.c index 437ddb8..458457c 100644 --- a/drivers/net/wireless/ti/wlcore/main.c +++ b/drivers/net/wireless/ti/wlcore/main.c @@ -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 */ -- 2.7.4