From 7c0b6bce6e848a59cd15d1ade9db346d34d90c5a Mon Sep 17 00:00:00 2001 From: Luuk Paulussen Date: Wed, 23 Dec 2015 09:51:14 +1300 Subject: [PATCH] staging: octeon: Fix logic for waking octeon ethernet tx queue. Only wake tx queue when driver queue is back within bounds. The logic here was just reenabling the queue when any buffers had been freed. the queue was stopped whenever the length exceeded 1000 (MAX_OUT_QUEUE_DEPTH), but then was essentially immediately started again. On a congested link, the queue length would just keep increasing up to around 8000 (for average size packets), at which point the hardware would start refusing the packets and they would begin to be dropped. This prevented the qdisc layer from effectively managing and prioritising packets, as essentially all packets were being allowed into the driver queue and then were being dropped by the hardware. This change only restarts the queue if the length is less than 1000 (MAX_OUT_QUEUE_DEPTH). Reviewed-by: Kyeong Yoo Reviewed-by: Chris Packham Reviewed-by: Richard Laing Signed-off-by: Luuk Paulussen Signed-off-by: Greg Kroah-Hartman --- drivers/staging/octeon/ethernet-tx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/octeon/ethernet-tx.c b/drivers/staging/octeon/ethernet-tx.c index 5611a0269aa8..82abaeca27a7 100644 --- a/drivers/staging/octeon/ethernet-tx.c +++ b/drivers/staging/octeon/ethernet-tx.c @@ -126,7 +126,7 @@ static void cvm_oct_free_tx_skbs(struct net_device *dev) } total_remaining += skb_queue_len(&priv->tx_free_list[qos]); } - if (total_freed >= 0 && netif_queue_stopped(dev)) + if (total_remaining < MAX_OUT_QUEUE_DEPTH && netif_queue_stopped(dev)) netif_wake_queue(dev); if (total_remaining) cvm_oct_kick_tx_poll_watchdog(); -- 2.20.1