diff options
Diffstat (limited to 'target/linux/generic/patches-3.3/046-fq_codel-qdisc-backlog.patch')
| -rw-r--r-- | target/linux/generic/patches-3.3/046-fq_codel-qdisc-backlog.patch | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/target/linux/generic/patches-3.3/046-fq_codel-qdisc-backlog.patch b/target/linux/generic/patches-3.3/046-fq_codel-qdisc-backlog.patch new file mode 100644 index 000000000..f9bcbbd08 --- /dev/null +++ b/target/linux/generic/patches-3.3/046-fq_codel-qdisc-backlog.patch @@ -0,0 +1,132 @@ +From 7bd90773f89001ea4960ed47676b550137f3facb Mon Sep 17 00:00:00 2001 +From: Eric Dumazet <edumazet@google.com> +Date: Wed, 16 May 2012 04:39:09 +0000 +Subject: [PATCH] fq_codel: should use qdisc backlog as threshold + +commit 865ec5523dadbedefbc5710a68969f686a28d928 upstream. + +codel_should_drop() logic allows a packet being not dropped if queue +size is under max packet size. + +In fq_codel, we have two possible backlogs : The qdisc global one, and +the flow local one. + +The meaningful one for codel_should_drop() should be the global backlog, +not the per flow one, so that thin flows can have a non zero drop/mark +probability. + +Signed-off-by: Eric Dumazet <edumazet@google.com> +Cc: Dave Taht <dave.taht@bufferbloat.net> +Cc: Kathleen Nichols <nichols@pollere.com> +Cc: Van Jacobson <van@pollere.net> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + include/net/codel.h | 15 +++++++-------- + net/sched/sch_codel.c | 4 ++-- + net/sched/sch_fq_codel.c | 5 +++-- + 3 files changed, 12 insertions(+), 12 deletions(-) + +--- a/include/net/codel.h ++++ b/include/net/codel.h +@@ -205,7 +205,7 @@ static codel_time_t codel_control_law(co + + + static bool codel_should_drop(const struct sk_buff *skb, +- unsigned int *backlog, ++ struct Qdisc *sch, + struct codel_vars *vars, + struct codel_params *params, + struct codel_stats *stats, +@@ -219,13 +219,13 @@ static bool codel_should_drop(const stru + } + + vars->ldelay = now - codel_get_enqueue_time(skb); +- *backlog -= qdisc_pkt_len(skb); ++ sch->qstats.backlog -= qdisc_pkt_len(skb); + + if (unlikely(qdisc_pkt_len(skb) > stats->maxpacket)) + stats->maxpacket = qdisc_pkt_len(skb); + + if (codel_time_before(vars->ldelay, params->target) || +- *backlog <= stats->maxpacket) { ++ sch->qstats.backlog <= stats->maxpacket) { + /* went below - stay below for at least interval */ + vars->first_above_time = 0; + return false; +@@ -249,8 +249,7 @@ static struct sk_buff *codel_dequeue(str + struct codel_params *params, + struct codel_vars *vars, + struct codel_stats *stats, +- codel_skb_dequeue_t dequeue_func, +- u32 *backlog) ++ codel_skb_dequeue_t dequeue_func) + { + struct sk_buff *skb = dequeue_func(vars, sch); + codel_time_t now; +@@ -261,7 +260,7 @@ static struct sk_buff *codel_dequeue(str + return skb; + } + now = codel_get_time(); +- drop = codel_should_drop(skb, backlog, vars, params, stats, now); ++ drop = codel_should_drop(skb, sch, vars, params, stats, now); + if (vars->dropping) { + if (!drop) { + /* sojourn time below target - leave dropping state */ +@@ -292,7 +291,7 @@ static struct sk_buff *codel_dequeue(str + qdisc_drop(skb, sch); + stats->drop_count++; + skb = dequeue_func(vars, sch); +- if (!codel_should_drop(skb, backlog, ++ if (!codel_should_drop(skb, sch, + vars, params, stats, now)) { + /* leave dropping state */ + vars->dropping = false; +@@ -313,7 +312,7 @@ static struct sk_buff *codel_dequeue(str + stats->drop_count++; + + skb = dequeue_func(vars, sch); +- drop = codel_should_drop(skb, backlog, vars, params, ++ drop = codel_should_drop(skb, sch, vars, params, + stats, now); + } + vars->dropping = true; +--- a/net/sched/sch_codel.c ++++ b/net/sched/sch_codel.c +@@ -77,8 +77,8 @@ static struct sk_buff *codel_qdisc_deque + struct codel_sched_data *q = qdisc_priv(sch); + struct sk_buff *skb; + +- skb = codel_dequeue(sch, &q->params, &q->vars, &q->stats, +- dequeue, &sch->qstats.backlog); ++ skb = codel_dequeue(sch, &q->params, &q->vars, &q->stats, dequeue); ++ + /* We cant call qdisc_tree_decrease_qlen() if our qlen is 0, + * or HTB crashes. Defer it for next round. + */ +--- a/net/sched/sch_fq_codel.c ++++ b/net/sched/sch_fq_codel.c +@@ -217,13 +217,14 @@ static int fq_codel_enqueue(struct sk_bu + */ + static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch) + { ++ struct fq_codel_sched_data *q = qdisc_priv(sch); + struct fq_codel_flow *flow; + struct sk_buff *skb = NULL; + + flow = container_of(vars, struct fq_codel_flow, cvars); + if (flow->head) { + skb = dequeue_head(flow); +- sch->qstats.backlog -= qdisc_pkt_len(skb); ++ q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb); + sch->q.qlen--; + } + return skb; +@@ -256,7 +257,7 @@ begin: + prev_ecn_mark = q->cstats.ecn_mark; + + skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats, +- dequeue, &q->backlogs[flow - q->flows]); ++ dequeue); + + flow->dropped += q->cstats.drop_count - prev_drop_count; + flow->dropped += q->cstats.ecn_mark - prev_ecn_mark; |