diff options
| -rw-r--r-- | net/sched/estimator.c | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/net/sched/estimator.c b/net/sched/estimator.c deleted file mode 100644 index 0ebc98e..0000000 --- a/net/sched/estimator.c +++ /dev/null @@ -1,196 +0,0 @@ -/* - * net/sched/estimator.c Simple rate estimator. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> - */ - -#include <asm/uaccess.h> -#include <asm/system.h> -#include <linux/bitops.h> -#include <linux/module.h> -#include <linux/types.h> -#include <linux/kernel.h> -#include <linux/jiffies.h> -#include <linux/string.h> -#include <linux/mm.h> -#include <linux/socket.h> -#include <linux/sockios.h> -#include <linux/in.h> -#include <linux/errno.h> -#include <linux/interrupt.h> -#include <linux/netdevice.h> -#include <linux/skbuff.h> -#include <linux/rtnetlink.h> -#include <linux/init.h> -#include <net/sock.h> -#include <net/pkt_sched.h> - -/* - This code is NOT intended to be used for statistics collection, - its purpose is to provide a base for statistical multiplexing - for controlled load service. - If you need only statistics, run a user level daemon which - periodically reads byte counters. - - Unfortunately, rate estimation is not a very easy task. - F.e. I did not find a simple way to estimate the current peak rate - and even failed to formulate the problem 8)8) - - So I preferred not to built an estimator into the scheduler, - but run this task separately. - Ideally, it should be kernel thread(s), but for now it runs - from timers, which puts apparent top bounds on the number of rated - flows, has minimal overhead on small, but is enough - to handle controlled load service, sets of aggregates. - - We measure rate over A=(1<<interval) seconds and evaluate EWMA: - - avrate = avrate*(1-W) + rate*W - - where W is chosen as negative power of 2: W = 2^(-ewma_log) - - The resulting time constant is: - - T = A/(-ln(1-W)) - - - NOTES. - - * The stored value for avbps is scaled by 2^5, so that maximal - rate is ~1Gbit, avpps is scaled by 2^10. - - * Minimal interval is HZ/4=250msec (it is the greatest common divisor - for HZ=100 and HZ=1024 8)), maximal interval - is (HZ*2^EST_MAX_INTERVAL)/4 = 8sec. Shorter intervals - are too expensive, longer ones can be implemented - at user level painlessly. - */ - -#define EST_MAX_INTERVAL 5 - -struct qdisc_estimator -{ - struct qdisc_estimator *next; - struct tc_stats *stats; - spinlock_t *stats_lock; - unsigned interval; - int ewma_log; - u64 last_bytes; - u32 last_packets; - u32 avpps; - u32 avbps; -}; - -struct qdisc_estimator_head -{ - struct timer_list timer; - struct qdisc_estimator *list; -}; - -static struct qdisc_estimator_head elist[EST_MAX_INTERVAL+1]; - -/* Estimator array lock */ -static DEFINE_RWLOCK(est_lock); - -static void est_timer(unsigned long arg) -{ - int idx = (int)arg; - struct qdisc_estimator *e; - - read_lock(&est_lock); - for (e = elist[idx].list; e; e = e->next) { - struct tc_stats *st = e->stats; - u64 nbytes; - u32 npackets; - u32 rate; - - spin_lock(e->stats_lock); - nbytes = st->bytes; - npackets = st->packets; - rate = (nbytes - e->last_bytes)<<(7 - idx); - e->last_bytes = nbytes; - e->avbps += ((long)rate - (long)e->avbps) >> e->ewma_log; - st->bps = (e->avbps+0xF)>>5; - - rate = (npackets - e->last_packets)<<(12 - idx); - e->last_packets = npackets; - e->avpps += ((long)rate - (long)e->avpps) >> e->ewma_log; - e->stats->pps = (e->avpps+0x1FF)>>10; - spin_unlock(e->stats_lock); - } - - mod_timer(&elist[idx].timer, jiffies + ((HZ<<idx)/4)); - read_unlock(&est_lock); -} - -int qdisc_new_estimator(struct tc_stats *stats, spinlock_t *stats_lock, struct rtattr *opt) -{ - struct qdisc_estimator *est; - struct tc_estimator *parm = RTA_DATA(opt); - - if (RTA_PAYLOAD(opt) < sizeof(*parm)) - return -EINVAL; - - if (parm->interval < -2 || parm->interval > 3) - return -EINVAL; - - est = kzalloc(sizeof(*est), GFP_KERNEL); - if (est == NULL) - return -ENOBUFS; - - est->interval = parm->interval + 2; - est->stats = stats; - est->stats_lock = stats_lock; - est->ewma_log = parm->ewma_log; - est->last_bytes = stats->bytes; - est->avbps = stats->bps<<5; - est->last_packets = stats->packets; - est->avpps = stats->pps<<10; - - est->next = elist[est->interval].list; - if (est->next == NULL) { - init_timer(&elist[est->interval].timer); - elist[est->interval].timer.data = est->interval; - elist[est->interval].timer.expires = jiffies + ((HZ<<est->interval)/4); - elist[est->interval].timer.function = est_timer; - add_timer(&elist[est->interval].timer); - } - write_lock_bh(&est_lock); - elist[est->interval].list = est; - write_unlock_bh(&est_lock); - return 0; -} - -void qdisc_kill_estimator(struct tc_stats *stats) -{ - int idx; - struct qdisc_estimator *est, **pest; - - for (idx=0; idx <= EST_MAX_INTERVAL; idx++) { - int killed = 0; - pest = &elist[idx].list; - while ((est=*pest) != NULL) { - if (est->stats != stats) { - pest = &est->next; - continue; - } - - write_lock_bh(&est_lock); - *pest = est->next; - write_unlock_bh(&est_lock); - - kfree(est); - killed++; - } - if (killed && elist[idx].list == NULL) - del_timer(&elist[idx].timer); - } -} - -EXPORT_SYMBOL(qdisc_kill_estimator); -EXPORT_SYMBOL(qdisc_new_estimator); |
