From a54cdbba9deee77ca48b5eec0c26fcc72538538c Mon Sep 17 00:00:00 2001 From: Dario Binacchi Date: Sat, 7 Aug 2021 15:07:58 +0200 Subject: [PATCH] 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: Dario Binacchi Signed-off-by: Marc Kleine-Budde --- 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 052ff35ed4dca..1ec0ce664732d 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