From:   David Mosberger-Tang <davidm@egauge.net>
Subject: [PATCH 01/23] wilc1000: don't hold txq_spinlock while initializing AC
 queue limits
Date:   Sat, 18 Dec 2021 23:54:16 +0000 (UTC)
Message-Id: <20211218235404.3963475-2-davidm@egauge.net>
In-Reply-To: <20211218235404.3963475-1-davidm@egauge.net>
References: <20211218235404.3963475-1-davidm@egauge.net>
MIME-Version: 1.0
To:     Ajay Singh <ajay.kathat@microchip.com>
Cc:     Claudiu Beznea <claudiu.beznea@microchip.com>,
        Kalle Valo <kvalo@codeaurora.org>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        David Mosberger-Tang <davidm@egauge.net>
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The wilc_tx_queue_status queue is relatively large and there is
absolutely no need to initialize it while holding a spinlock.

Signed-off-by: David Mosberger-Tang <davidm@egauge.net>
---
 .../net/wireless/microchip/wilc1000/netdev.h  |  1 -
 .../net/wireless/microchip/wilc1000/wlan.c    | 32 +++++++++++--------
 2 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/drivers/net/wireless/microchip/wilc1000/netdev.h b/drivers/net/wireless/microchip/wilc1000/netdev.h
index b9a88b3e322f1..fd0cb01e538a2 100644
--- a/drivers/net/wireless/microchip/wilc1000/netdev.h
+++ b/drivers/net/wireless/microchip/wilc1000/netdev.h
@@ -202,7 +202,6 @@ struct wilc_tx_queue_status {
 	u16 end_index;
 	u16 cnt[NQUEUES];
 	u16 sum;
-	bool initialized;
 };
 
 struct wilc {
diff --git a/drivers/net/wireless/microchip/wilc1000/wlan.c b/drivers/net/wireless/microchip/wilc1000/wlan.c
index 1aa4236a2fe41..721e6131125e8 100644
--- a/drivers/net/wireless/microchip/wilc1000/wlan.c
+++ b/drivers/net/wireless/microchip/wilc1000/wlan.c
@@ -12,6 +12,8 @@
 
 #define WAKE_UP_TRIAL_RETRY		10000
 
+static const u8 factors[NQUEUES] = {1, 1, 1, 1};
+
 static inline bool is_wilc1000(u32 id)
 {
 	return (id & (~WILC_CHIP_REV_FIELD)) == WILC_1000_BASE_ID;
@@ -283,10 +285,23 @@ static int wilc_wlan_txq_add_cfg_pkt(struct wilc_vif *vif, u8 *buffer,
 	return 1;
 }
 
+static void init_q_limits(struct wilc *wl)
+{
+	struct wilc_tx_queue_status *q = &wl->tx_q_limit;
+	int i;
+
+	for (i = 0; i < AC_BUFFER_SIZE; i++)
+		q->buffer[i] = i % NQUEUES;
+
+	for (i = 0; i < NQUEUES; i++) {
+		q->cnt[i] = AC_BUFFER_SIZE * factors[i] / NQUEUES;
+		q->sum += q->cnt[i];
+	}
+	q->end_index = AC_BUFFER_SIZE - 1;
+}
+
 static bool is_ac_q_limit(struct wilc *wl, u8 q_num)
 {
-	u8 factors[NQUEUES] = {1, 1, 1, 1};
-	u16 i;
 	unsigned long flags;
 	struct wilc_tx_queue_status *q = &wl->tx_q_limit;
 	u8 end_index;
@@ -294,17 +309,6 @@ static bool is_ac_q_limit(struct wilc *wl, u8 q_num)
 	bool ret = false;
 
 	spin_lock_irqsave(&wl->txq_spinlock, flags);
-	if (!q->initialized) {
-		for (i = 0; i < AC_BUFFER_SIZE; i++)
-			q->buffer[i] = i % NQUEUES;
-
-		for (i = 0; i < NQUEUES; i++) {
-			q->cnt[i] = AC_BUFFER_SIZE * factors[i] / NQUEUES;
-			q->sum += q->cnt[i];
-		}
-		q->end_index = AC_BUFFER_SIZE - 1;
-		q->initialized = 1;
-	}
 
 	end_index = q->end_index;
 	q->cnt[q->buffer[end_index]] -= factors[q->buffer[end_index]];
@@ -1485,6 +1489,8 @@ int wilc_wlan_init(struct net_device *dev)
 		goto fail;
 	}
 
+	init_q_limits(wilc);
+
 	if (!wilc->tx_buffer)
 		wilc->tx_buffer = kmalloc(WILC_TX_BUFF_SIZE, GFP_KERNEL);
 
-- 
2.25.1