Received-SPF: pass (google.com: domain of linux-kernel+bounces-54571-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
From: Paul Barker <paul.barker.ct@bp.renesas.com>
To: Sergey Shtylyov <s.shtylyov@omp.ru>,
	"David S . Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>,
	Paolo Abeni <pabeni@redhat.com>
Cc: Paul Barker <paul.barker.ct@bp.renesas.com>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	Wolfram Sang <wsa+renesas@sang-engineering.com>,
	netdev@vger.kernel.org,
	linux-renesas-soc@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [RFC PATCH net-next v2 3/7] net: ravb: Always process TX descriptor ring
Date: Tue,  6 Feb 2024 09:19:05 +0000
Message-Id: <20240206091909.3191-4-paul.barker.ct@bp.renesas.com>
In-Reply-To: <20240206091909.3191-1-paul.barker.ct@bp.renesas.com>
References: <20240206091909.3191-1-paul.barker.ct@bp.renesas.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

The TX queue should be serviced each time the poll function is called,
even if the full RX work budget has been consumed. This prevents
starvation of the TX queue when RX bandwidth usage is high.

Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
---
 drivers/net/ethernet/renesas/ravb_main.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 20193944c143..10f11141569f 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -1349,8 +1349,6 @@ static int ravb_poll(struct napi_struct *napi, int budget)
 	/* Clear RX interrupt */
 	ravb_write(ndev, ~(mask | RIS0_RESERVED), RIS0);
 	work_done = ravb_rx(ndev, budget, q);
-	if (work_done == budget)
-		goto out;
 
 	/* Processing TX Descriptor Ring */
 	spin_lock_irqsave(&priv->lock, flags);
@@ -1360,6 +1358,9 @@ static int ravb_poll(struct napi_struct *napi, int budget)
 	netif_wake_subqueue(ndev, q);
 	spin_unlock_irqrestore(&priv->lock, flags);
 
+	if (work_done == budget)
+		goto out;
+
 	napi_complete(napi);
 
 	/* Re-enable RX/TX interrupts */
-- 
2.39.2