summaryrefslogtreecommitdiff
path: root/net/sched/sch_netem.c
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2017-09-19 15:14:24 +0300
committerDavid S. Miller <davem@davemloft.net>2017-09-20 01:20:22 +0300
commitbffa72cf7f9df842f0016ba03586039296b4caaf (patch)
treee27752d22b270c0c607ff8025e44dd8f884aa1cb /net/sched/sch_netem.c
parenta38b2fa37e2e2ac897e7159738c5763ee65ee405 (diff)
downloadlinux-bffa72cf7f9df842f0016ba03586039296b4caaf.tar.xz
net: sk_buff rbnode reorg
skb->rbnode shares space with skb->next, skb->prev and skb->tstamp Current uses (TCP receive ofo queue and netem) need to save/restore tstamp, while skb->dev is either NULL (TCP) or a constant for a given queue (netem). Since we plan using an RB tree for TCP retransmit queue to speedup SACK processing with large BDP, this patch exchanges skb->dev and skb->tstamp. This saves some overhead in both TCP and netem. v2: removes the swtstamp field from struct tcp_skb_cb Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Wei Wang <weiwan@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched/sch_netem.c')
-rw-r--r--net/sched/sch_netem.c7
1 files changed, 4 insertions, 3 deletions
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index b1266e75ca43..063a4bdb9ee6 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -146,7 +146,6 @@ struct netem_sched_data {
*/
struct netem_skb_cb {
psched_time_t time_to_send;
- ktime_t tstamp_save;
};
@@ -561,7 +560,6 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch,
}
cb->time_to_send = now + delay;
- cb->tstamp_save = skb->tstamp;
++q->counter;
tfifo_enqueue(skb, sch);
} else {
@@ -629,7 +627,10 @@ deliver:
qdisc_qstats_backlog_dec(sch, skb);
skb->next = NULL;
skb->prev = NULL;
- skb->tstamp = netem_skb_cb(skb)->tstamp_save;
+ /* skb->dev shares skb->rbnode area,
+ * we need to restore its value.
+ */
+ skb->dev = qdisc_dev(sch);
#ifdef CONFIG_NET_CLS_ACT
/*