diff options
-rw-r--r-- | net/sched/sch_pie.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/net/sched/sch_pie.c b/net/sched/sch_pie.c index 30f158582499..916b878d3491 100644 --- a/net/sched/sch_pie.c +++ b/net/sched/sch_pie.c @@ -55,8 +55,10 @@ struct pie_vars { psched_time_t qdelay_old; u64 dq_count; /* measured in bytes */ psched_time_t dq_tstamp; /* drain rate */ + u64 accu_prob; /* accumulated drop probability */ u32 avg_dq_rate; /* bytes per pschedtime tick,scaled */ u32 qlen_old; /* in bytes */ + u8 accu_prob_overflows; /* overflows of accu_prob */ }; /* statistics gathering */ @@ -91,9 +93,11 @@ static void pie_params_init(struct pie_params *params) static void pie_vars_init(struct pie_vars *vars) { vars->dq_count = DQCOUNT_INVALID; + vars->accu_prob = 0; vars->avg_dq_rate = 0; /* default of 150 ms in pschedtime */ vars->burst_time = PSCHED_NS2TICKS(150 * NSEC_PER_MSEC); + vars->accu_prob_overflows = 0; } static bool drop_early(struct Qdisc *sch, u32 packet_size) @@ -128,9 +132,29 @@ static bool drop_early(struct Qdisc *sch, u32 packet_size) else local_prob = q->vars.prob; + if (local_prob == 0) { + q->vars.accu_prob = 0; + q->vars.accu_prob_overflows = 0; + } + + if (local_prob > MAX_PROB - q->vars.accu_prob) + q->vars.accu_prob_overflows++; + + q->vars.accu_prob += local_prob; + + if (q->vars.accu_prob_overflows == 0 && + q->vars.accu_prob < (MAX_PROB / 100) * 85) + return false; + if (q->vars.accu_prob_overflows == 8 && + q->vars.accu_prob >= MAX_PROB / 2) + return true; + prandom_bytes(&rnd, 8); - if (rnd < local_prob) + if (rnd < local_prob) { + q->vars.accu_prob = 0; + q->vars.accu_prob_overflows = 0; return true; + } return false; } @@ -168,6 +192,8 @@ static int pie_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch, out: q->stats.dropped++; + q->vars.accu_prob = 0; + q->vars.accu_prob_overflows = 0; return qdisc_drop(skb, sch, to_free); } |