| 1 | From: Eric Dumazet <eric.dumazet@gmail.com> |
| 2 | Date: Fri, 29 Jul 2011 19:22:42 +0000 (+0000) |
| 3 | Subject: sch_sfq: fix sfq_enqueue() |
| 4 | X-Git-Tag: v3.1-rc1~24^2~29 |
| 5 | X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=e1738bd9cecc5c867b0e2996470c1ff20f66ba79 |
| 6 | |
| 7 | sch_sfq: fix sfq_enqueue() |
| 8 | |
| 9 | commit 8efa88540635 (sch_sfq: avoid giving spurious NET_XMIT_CN signals) |
| 10 | forgot to call qdisc_tree_decrease_qlen() to signal upper levels that a |
| 11 | packet (from another flow) was dropped, leading to various problems. |
| 12 | |
| 13 | With help from Michal Soltys and Michal Pokrywka, who did a bisection. |
| 14 | |
| 15 | Bugzilla ref: https://bugzilla.kernel.org/show_bug.cgi?id=39372 |
| 16 | Debian ref: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=631945 |
| 17 | |
| 18 | Reported-by: Lucas Bocchi <lucas.bocchi@gmail.com> |
| 19 | Reported-and-bisected-by: Michal Pokrywka <wolfmoon@o2.pl> |
| 20 | Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> |
| 21 | CC: Michal Soltys <soltys@ziu.info> |
| 22 | Acked-by: Patrick McHardy <kaber@trash.net> |
| 23 | Signed-off-by: David S. Miller <davem@davemloft.net> |
| 24 | --- |
| 25 | |
| 26 | --- a/net/sched/sch_sfq.c |
| 27 | +++ b/net/sched/sch_sfq.c |
| 28 | @@ -410,7 +410,12 @@ sfq_enqueue(struct sk_buff *skb, struct |
| 29 | /* Return Congestion Notification only if we dropped a packet |
| 30 | * from this flow. |
| 31 | */ |
| 32 | - return (qlen != slot->qlen) ? NET_XMIT_CN : NET_XMIT_SUCCESS; |
| 33 | + if (qlen != slot->qlen) |
| 34 | + return NET_XMIT_CN; |
| 35 | + |
| 36 | + /* As we dropped a packet, better let upper stack know this */ |
| 37 | + qdisc_tree_decrease_qlen(sch, 1); |
| 38 | + return NET_XMIT_SUCCESS; |
| 39 | } |
| 40 | |
| 41 | static struct sk_buff * |
| 42 | |
