74d00a8c38
* properly format/comment all patches * merge debloat patches * merge Kconfig patches * merge swconfig patches * merge hotplug patches * drop 200-fix_localversion.patch - upstream * drop 222-arm_zimage_none.patch - unused * drop 252-mv_cesa_depends.patch - no longer required * drop 410-mtd-move-forward-declaration-of-struct-mtd_info.patch - unused * drop 661-fq_codel_keep_dropped_stats.patch - outdated * drop 702-phy_add_aneg_done_function.patch - upstream * drop 840-rtc7301.patch - unused * drop 841-rtc_pt7c4338.patch - upstream * drop 921-use_preinit_as_init.patch - unused * drop spio-gpio-old and gpio-mmc - unused Signed-off-by: John Crispin <john@phrozen.org>
70 lines
2.6 KiB
Diff
70 lines
2.6 KiB
Diff
From: Eric Dumazet <edumazet@google.com>
|
|
Date: Sat, 4 Jun 2016 12:55:13 -0700
|
|
Subject: [PATCH] fq_codel: fix NET_XMIT_CN behavior
|
|
|
|
My prior attempt to fix the backlogs of parents failed.
|
|
|
|
If we return NET_XMIT_CN, our parents wont increase their backlog,
|
|
so our qdisc_tree_reduce_backlog() should take this into account.
|
|
|
|
v2: Florian Westphal pointed out that we could drop the packet,
|
|
so we need to save qdisc_pkt_len(skb) in a temp variable before
|
|
calling fq_codel_drop()
|
|
|
|
Fixes: 9d18562a2278 ("fq_codel: add batch ability to fq_codel_drop()")
|
|
Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too")
|
|
Reported-by: Stas Nichiporovich <stasn77@gmail.com>
|
|
Signed-off-by: Eric Dumazet <edumazet@google.com>
|
|
Cc: WANG Cong <xiyou.wangcong@gmail.com>
|
|
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
|
|
---
|
|
|
|
--- a/net/sched/sch_fq_codel.c
|
|
+++ b/net/sched/sch_fq_codel.c
|
|
@@ -197,6 +197,7 @@ static int fq_codel_enqueue(struct sk_bu
|
|
unsigned int idx, prev_backlog, prev_qlen;
|
|
struct fq_codel_flow *flow;
|
|
int uninitialized_var(ret);
|
|
+ unsigned int pkt_len;
|
|
bool memory_limited;
|
|
|
|
idx = fq_codel_classify(skb, sch, &ret);
|
|
@@ -228,6 +229,8 @@ static int fq_codel_enqueue(struct sk_bu
|
|
prev_backlog = sch->qstats.backlog;
|
|
prev_qlen = sch->q.qlen;
|
|
|
|
+ /* save this packet length as it might be dropped by fq_codel_drop() */
|
|
+ pkt_len = qdisc_pkt_len(skb);
|
|
/* fq_codel_drop() is quite expensive, as it performs a linear search
|
|
* in q->backlogs[] to find a fat flow.
|
|
* So instead of dropping a single packet, drop half of its backlog
|
|
@@ -235,14 +238,23 @@ static int fq_codel_enqueue(struct sk_bu
|
|
*/
|
|
ret = fq_codel_drop(sch, q->drop_batch_size);
|
|
|
|
- q->drop_overlimit += prev_qlen - sch->q.qlen;
|
|
+ prev_qlen -= sch->q.qlen;
|
|
+ prev_backlog -= sch->qstats.backlog;
|
|
+ q->drop_overlimit += prev_qlen;
|
|
if (memory_limited)
|
|
- q->drop_overmemory += prev_qlen - sch->q.qlen;
|
|
- /* As we dropped packet(s), better let upper stack know this */
|
|
- qdisc_tree_reduce_backlog(sch, prev_qlen - sch->q.qlen,
|
|
- prev_backlog - sch->qstats.backlog);
|
|
+ q->drop_overmemory += prev_qlen;
|
|
|
|
- return ret == idx ? NET_XMIT_CN : NET_XMIT_SUCCESS;
|
|
+ /* As we dropped packet(s), better let upper stack know this.
|
|
+ * If we dropped a packet for this flow, return NET_XMIT_CN,
|
|
+ * but in this case, our parents wont increase their backlogs.
|
|
+ */
|
|
+ if (ret == idx) {
|
|
+ qdisc_tree_reduce_backlog(sch, prev_qlen - 1,
|
|
+ prev_backlog - pkt_len);
|
|
+ return NET_XMIT_CN;
|
|
+ }
|
|
+ qdisc_tree_reduce_backlog(sch, prev_qlen, prev_backlog);
|
|
+ return NET_XMIT_SUCCESS;
|
|
}
|
|
|
|
/* This is the specific function called from codel_dequeue()
|