can: peak/pcie_fd: fix potential bug in restarting tx queue

Don't rely on can_get_echo_skb() return value to wake the network tx
queue up: can_get_echo_skb() returns 0 if the echo array slot was not
occupied, but also when the DLC of the released echo frame was 0.

Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Stephane Grosjean 2017-12-07 16:13:43 +01:00 committed by Marc Kleine-Budde
parent 12147edc43
commit 91785de6f9
1 changed files with 3 additions and 6 deletions

View File

@ -258,21 +258,18 @@ static int pucan_handle_can_rx(struct peak_canfd_priv *priv,
/* if this frame is an echo, */
if ((rx_msg_flags & PUCAN_MSG_LOOPED_BACK) &&
!(rx_msg_flags & PUCAN_MSG_SELF_RECEIVE)) {
int n;
unsigned long flags;
spin_lock_irqsave(&priv->echo_lock, flags);
n = can_get_echo_skb(priv->ndev, msg->client);
can_get_echo_skb(priv->ndev, msg->client);
spin_unlock_irqrestore(&priv->echo_lock, flags);
/* count bytes of the echo instead of skb */
stats->tx_bytes += cf_len;
stats->tx_packets++;
if (n) {
/* restart tx queue only if a slot is free */
netif_wake_queue(priv->ndev);
}
/* restart tx queue (a slot is free) */
netif_wake_queue(priv->ndev);
return 0;
}