Commit a54cdbba authored by Dario Binacchi's avatar Dario Binacchi Committed by Marc Kleine-Budde
Browse files

can: c_can: exit c_can_do_tx() early if no frames have been sent 

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.

Link: https://lore.kernel.org/r/20210807130800.5246-3-dariobin@libero.it


Signed-off-by: default avatarDario Binacchi <dariobin@libero.it>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 5064e405

drivers/net/can/c_can/c_can_main.c

+6 −5
Original line number Original line Diff line number Diff line
@@ -720,18 +720,19 @@ static void c_can_do_tx(struct net_device *dev) 
		pkts++;

		pkts++;

	}

	}





	if (!pkts)

		return;



	/* Clear the bits in the tx_active mask */

	/* Clear the bits in the tx_active mask */

	atomic_sub(clr, &priv->tx_active);

	atomic_sub(clr, &priv->tx_active);





	if (clr & BIT(priv->msg_obj_tx_num - 1))

	if (clr & BIT(priv->msg_obj_tx_num - 1))

		netif_wake_queue(dev);

		netif_wake_queue(dev);





	if (pkts) {

	stats->tx_bytes += bytes;

	stats->tx_bytes += bytes;

	stats->tx_packets += pkts;

	stats->tx_packets += pkts;

	can_led_event(dev, CAN_LED_EVENT_TX);

	can_led_event(dev, CAN_LED_EVENT_TX);

}

}

}





/* If we have a gap in the pending bits, that means we either

/* If we have a gap in the pending bits, that means we either

 * raced with the hardware or failed to readout all upper

 * raced with the hardware or failed to readout all upper