From patchwork Thu Jul 2 16:29:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 11639569 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8B1CA618 for ; Thu, 2 Jul 2020 16:30:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79EB120760 for ; Thu, 2 Jul 2020 16:30:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726844AbgGBQ36 (ORCPT ); Thu, 2 Jul 2020 12:29:58 -0400 Received: from muru.com ([72.249.23.125]:60398 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726791AbgGBQ36 (ORCPT ); Thu, 2 Jul 2020 12:29:58 -0400 Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id 059F98062; Thu, 2 Jul 2020 16:30:50 +0000 (UTC) From: Tony Lindgren To: Kalle Valo Cc: Eyal Reizer , Guy Mishol , linux-wireless@vger.kernel.org, linux-omap@vger.kernel.org Subject: [PATCH 3/4] wlcore: Use spin_trylock in wlcore_irq() to see if we need to queue tx Date: Thu, 2 Jul 2020 09:29:50 -0700 Message-Id: <20200702162951.45392-4-tony@atomide.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200702162951.45392-1-tony@atomide.com> References: <20200702162951.45392-1-tony@atomide.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org 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: Tony Lindgren --- drivers/net/wireless/ti/wlcore/main.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/ti/wlcore/main.c b/drivers/net/wireless/ti/wlcore/main.c --- a/drivers/net/wireless/ti/wlcore/main.c +++ b/drivers/net/wireless/ti/wlcore/main.c @@ -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); - 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)) + 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);