[215/241] net-rps: Fix brokeness causing OOO packets

Submitted by Herton Ronaldo Krzesinski on Dec. 13, 2012, 1:59 p.m.

Details

Message ID 1355407206-17100-216-git-send-email-herton.krzesinski@canonical.com
State New
Headers show

Commit Message

Herton Ronaldo Krzesinski Dec. 13, 2012, 1:59 p.m.
3.5.7.2 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Tom Herbert <therbert@google.com>

commit baefa31db2f2b13a05d1b81bdf2d20d487f58b0a upstream.

In commit c445477d74ab3779 which adds aRFS to the kernel, the CPU
selected for RFS is not set correctly when CPU is changing.
This is causing OOO packets and probably other issues.

Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
---
 net/core/dev.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Patch hide | download patch | download mbox

diff --git a/net/core/dev.c b/net/core/dev.c
index 75845ba..3ad746b 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2761,8 +2761,10 @@  static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
 		if (unlikely(tcpu != next_cpu) &&
 		    (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
 		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
-		      rflow->last_qtail)) >= 0))
+		      rflow->last_qtail)) >= 0)) {
+			tcpu = next_cpu;
 			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
+		}
 
 		if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
 			*rflowp = rflow;