From: Dario Binacchi <dariobin@libero.it>
To: linux-kernel@vger.kernel.org
Cc: Gianluca Falavigna <gianluca.falavigna@inwind.it>,
Dario Binacchi <dariobin@libero.it>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Marc Kleine-Budde <mkl@pengutronix.de>,
Oliver Hartkopp <socketcan@hartkopp.net>,
Vincent Mailhol <mailhol.vincent@wanadoo.fr>,
Wolfgang Grandegger <wg@grandegger.com>,
linux-can@vger.kernel.org, netdev@vger.kernel.org
Subject: [PATCH v2 2/4] can: c_can: exit c_can_do_tx() early if no frames have been sent
Date: Thu, 5 Aug 2021 22:18:58 +0200 [thread overview]
Message-ID: <20210805201900.23146-3-dariobin@libero.it> (raw)
In-Reply-To: <20210805201900.23146-1-dariobin@libero.it>
The c_can_poll() handles RX/TX events unconditionally. It may therefore
happen that c_can_do_tx() is called unnecessarily because the interrupt
was triggered by the reception of a frame. In these cases, we avoid to
execute unnecessary statements and exit immediately.
Signed-off-by: Dario Binacchi <dariobin@libero.it>
---
(no changes since v1)
drivers/net/can/c_can/c_can_main.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/net/can/c_can/c_can_main.c b/drivers/net/can/c_can/c_can_main.c
index 7588f70ca0fe..fec0e3416970 100644
--- a/drivers/net/can/c_can/c_can_main.c
+++ b/drivers/net/can/c_can/c_can_main.c
@@ -720,17 +720,18 @@ static void c_can_do_tx(struct net_device *dev)
pkts++;
}
+ if (!pkts)
+ return;
+
/* Clear the bits in the tx_active mask */
atomic_sub(clr, &priv->tx_active);
if (clr & BIT(priv->msg_obj_tx_num - 1))
netif_wake_queue(dev);
- if (pkts) {
- stats->tx_bytes += bytes;
- stats->tx_packets += pkts;
- can_led_event(dev, CAN_LED_EVENT_TX);
- }
+ stats->tx_bytes += bytes;
+ stats->tx_packets += pkts;
+ can_led_event(dev, CAN_LED_EVENT_TX);
}
/* If we have a gap in the pending bits, that means we either
--
2.17.1
next prev parent reply other threads:[~2021-08-05 20:20 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-05 20:18 [PATCH v2 0/4] can: c_can: cache frames to operate as a true FIFO Dario Binacchi
2021-08-05 20:18 ` [PATCH v2 1/4] can: c_can: remove struct c_can_priv::priv field Dario Binacchi
2021-08-05 20:18 ` Dario Binacchi [this message]
2021-08-05 20:18 ` [PATCH v2 3/4] can: c_can: support tx ring algorithm Dario Binacchi
2021-08-05 20:19 ` [PATCH v2 4/4] can: c_can: cache frames to operate as a true FIFO Dario Binacchi
2021-08-06 9:36 ` Marc Kleine-Budde
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