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@@ -1,196 +0,0 @@
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-/*
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- * net/sched/estimator.c Simple rate estimator.
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- *
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- * This program is free software; you can redistribute it and/or
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- * modify it under the terms of the GNU General Public License
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- * as published by the Free Software Foundation; either version
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- * 2 of the License, or (at your option) any later version.
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- *
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- * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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- */
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-
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-#include <asm/uaccess.h>
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-#include <asm/system.h>
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-#include <linux/bitops.h>
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-#include <linux/module.h>
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-#include <linux/types.h>
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-#include <linux/kernel.h>
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-#include <linux/jiffies.h>
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-#include <linux/string.h>
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-#include <linux/mm.h>
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-#include <linux/socket.h>
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-#include <linux/sockios.h>
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-#include <linux/in.h>
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-#include <linux/errno.h>
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-#include <linux/interrupt.h>
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-#include <linux/netdevice.h>
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-#include <linux/skbuff.h>
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-#include <linux/rtnetlink.h>
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-#include <linux/init.h>
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-#include <net/sock.h>
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-#include <net/pkt_sched.h>
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-
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-/*
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- This code is NOT intended to be used for statistics collection,
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- its purpose is to provide a base for statistical multiplexing
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- for controlled load service.
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- If you need only statistics, run a user level daemon which
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- periodically reads byte counters.
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-
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- Unfortunately, rate estimation is not a very easy task.
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- F.e. I did not find a simple way to estimate the current peak rate
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- and even failed to formulate the problem 8)8)
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-
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- So I preferred not to built an estimator into the scheduler,
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- but run this task separately.
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- Ideally, it should be kernel thread(s), but for now it runs
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- from timers, which puts apparent top bounds on the number of rated
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- flows, has minimal overhead on small, but is enough
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- to handle controlled load service, sets of aggregates.
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-
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- We measure rate over A=(1<<interval) seconds and evaluate EWMA:
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-
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- avrate = avrate*(1-W) + rate*W
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-
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- where W is chosen as negative power of 2: W = 2^(-ewma_log)
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-
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- The resulting time constant is:
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-
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- T = A/(-ln(1-W))
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-
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-
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- NOTES.
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-
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- * The stored value for avbps is scaled by 2^5, so that maximal
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- rate is ~1Gbit, avpps is scaled by 2^10.
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-
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- * Minimal interval is HZ/4=250msec (it is the greatest common divisor
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- for HZ=100 and HZ=1024 8)), maximal interval
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- is (HZ*2^EST_MAX_INTERVAL)/4 = 8sec. Shorter intervals
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- are too expensive, longer ones can be implemented
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- at user level painlessly.
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- */
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-
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-#define EST_MAX_INTERVAL 5
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-
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-struct qdisc_estimator
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-{
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- struct qdisc_estimator *next;
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- struct tc_stats *stats;
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- spinlock_t *stats_lock;
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- unsigned interval;
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- int ewma_log;
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- u64 last_bytes;
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- u32 last_packets;
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- u32 avpps;
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- u32 avbps;
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-};
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-
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-struct qdisc_estimator_head
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-{
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- struct timer_list timer;
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- struct qdisc_estimator *list;
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-};
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-
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-static struct qdisc_estimator_head elist[EST_MAX_INTERVAL+1];
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-
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-/* Estimator array lock */
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-static DEFINE_RWLOCK(est_lock);
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-
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-static void est_timer(unsigned long arg)
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-{
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- int idx = (int)arg;
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- struct qdisc_estimator *e;
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-
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- read_lock(&est_lock);
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- for (e = elist[idx].list; e; e = e->next) {
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- struct tc_stats *st = e->stats;
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- u64 nbytes;
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- u32 npackets;
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- u32 rate;
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-
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- spin_lock(e->stats_lock);
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- nbytes = st->bytes;
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- npackets = st->packets;
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- rate = (nbytes - e->last_bytes)<<(7 - idx);
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- e->last_bytes = nbytes;
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- e->avbps += ((long)rate - (long)e->avbps) >> e->ewma_log;
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- st->bps = (e->avbps+0xF)>>5;
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-
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- rate = (npackets - e->last_packets)<<(12 - idx);
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- e->last_packets = npackets;
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- e->avpps += ((long)rate - (long)e->avpps) >> e->ewma_log;
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- e->stats->pps = (e->avpps+0x1FF)>>10;
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- spin_unlock(e->stats_lock);
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- }
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-
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- mod_timer(&elist[idx].timer, jiffies + ((HZ<<idx)/4));
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- read_unlock(&est_lock);
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-}
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-
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-int qdisc_new_estimator(struct tc_stats *stats, spinlock_t *stats_lock, struct rtattr *opt)
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-{
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- struct qdisc_estimator *est;
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- struct tc_estimator *parm = RTA_DATA(opt);
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-
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- if (RTA_PAYLOAD(opt) < sizeof(*parm))
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- return -EINVAL;
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-
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- if (parm->interval < -2 || parm->interval > 3)
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- return -EINVAL;
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-
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- est = kzalloc(sizeof(*est), GFP_KERNEL);
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- if (est == NULL)
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- return -ENOBUFS;
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-
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- est->interval = parm->interval + 2;
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- est->stats = stats;
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- est->stats_lock = stats_lock;
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- est->ewma_log = parm->ewma_log;
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- est->last_bytes = stats->bytes;
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- est->avbps = stats->bps<<5;
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- est->last_packets = stats->packets;
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- est->avpps = stats->pps<<10;
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-
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- est->next = elist[est->interval].list;
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- if (est->next == NULL) {
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- init_timer(&elist[est->interval].timer);
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- elist[est->interval].timer.data = est->interval;
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- elist[est->interval].timer.expires = jiffies + ((HZ<<est->interval)/4);
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- elist[est->interval].timer.function = est_timer;
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- add_timer(&elist[est->interval].timer);
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- }
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- write_lock_bh(&est_lock);
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- elist[est->interval].list = est;
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- write_unlock_bh(&est_lock);
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- return 0;
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-}
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-
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-void qdisc_kill_estimator(struct tc_stats *stats)
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-{
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- int idx;
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- struct qdisc_estimator *est, **pest;
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-
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- for (idx=0; idx <= EST_MAX_INTERVAL; idx++) {
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- int killed = 0;
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- pest = &elist[idx].list;
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- while ((est=*pest) != NULL) {
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- if (est->stats != stats) {
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- pest = &est->next;
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- continue;
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- }
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-
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- write_lock_bh(&est_lock);
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- *pest = est->next;
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- write_unlock_bh(&est_lock);
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-
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- kfree(est);
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- killed++;
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- }
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- if (killed && elist[idx].list == NULL)
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- del_timer(&elist[idx].timer);
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- }
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-}
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-
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-EXPORT_SYMBOL(qdisc_kill_estimator);
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-EXPORT_SYMBOL(qdisc_new_estimator);
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