From f0796d5c73e59786d09a1e617689d1d415f2db44 Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Thu, 1 Jul 2010 13:21:57 +0000 Subject: net: decreasing real_num_tx_queues needs to flush qdisc Reducing real_num_queues needs to flush the qdisc otherwise skbs with queue_mappings greater then real_num_tx_queues can be sent to the underlying driver. The flow for this is, dev_queue_xmit() dev_pick_tx() skb_tx_hash() => hash using real_num_tx_queues skb_set_queue_mapping() ... qdisc_enqueue_root() => enqueue skb on txq from hash ... dev->real_num_tx_queues -= n ... sch_direct_xmit() dev_hard_start_xmit() ndo_start_xmit(skb,dev) => skb queue set with old hash skbs are enqueued on the qdisc with skb->queue_mapping set 0 < queue_mappings < real_num_tx_queues. When the driver decreases real_num_tx_queues skb's may be dequeued from the qdisc with a queue_mapping greater then real_num_tx_queues. This fixes a case in ixgbe where this was occurring with DCB and FCoE. Because the driver is using queue_mapping to map skbs to tx descriptor rings we can potentially map skbs to rings that no longer exist. Signed-off-by: John Fastabend Tested-by: Ross Brattain Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- include/linux/netdevice.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 40291f375024..5e6188d9f017 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1656,6 +1656,9 @@ static inline int netif_is_multiqueue(const struct net_device *dev) return (dev->num_tx_queues > 1); } +extern void netif_set_real_num_tx_queues(struct net_device *dev, + unsigned int txq); + /* Use this variant when it is known for sure that it * is executing from hardware interrupt context or with hardware interrupts * disabled. -- cgit v1.2.1 From bcfcc450baaaa44afc1d3c51ef96a53338ff0eb2 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Fri, 2 Jul 2010 07:08:44 +0000 Subject: net: Fix definition of netif_vdbg() when VERBOSE_DEBUG is defined netif_vdbg() was originally defined as entirely equivalent to netdev_vdbg(), but I assume that it was intended to take the same parameters as netif_dbg() etc. (Currently it is only used by the sfc driver, in which I worked on that assumption.) In commit a4ed89c I changed the definition used when VERBOSE_DEBUG is not defined, but I failed to notice that the definition used when VERBOSE_DEBUG is defined was also not as I expected. Change that to match netif_dbg() as well. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller --- include/linux/netdevice.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 5e6188d9f017..b21e4054c12c 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2332,7 +2332,7 @@ do { \ #endif #if defined(VERBOSE_DEBUG) -#define netif_vdbg netdev_dbg +#define netif_vdbg netif_dbg #else #define netif_vdbg(priv, type, dev, format, args...) \ ({ \ -- cgit v1.2.1