mirror of
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Merge branch 'red' of 84.73.165.173:/home/tgr/repos/net-2.6
This commit is contained in:
Arnaldo Carvalho de Melo
commit
2d43f1128a
@ -93,6 +93,7 @@ struct tc_fifo_qopt
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/* PRIO section */
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#define TCQ_PRIO_BANDS 16
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#define TCQ_MIN_PRIO_BANDS 2
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struct tc_prio_qopt
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{
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@ -169,6 +170,7 @@ struct tc_red_qopt
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unsigned char Scell_log; /* cell size for idle damping */
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unsigned char flags;
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#define TC_RED_ECN 1
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#define TC_RED_HARDDROP 2
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};
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struct tc_red_xstats
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@ -194,38 +196,34 @@ enum
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#define TCA_GRED_MAX (__TCA_GRED_MAX - 1)
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#define TCA_SET_OFF TCA_GRED_PARMS
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struct tc_gred_qopt
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{
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__u32 limit; /* HARD maximal queue length (bytes)
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*/
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__u32 qth_min; /* Min average length threshold (bytes)
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*/
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__u32 qth_max; /* Max average length threshold (bytes)
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*/
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__u32 DP; /* upto 2^32 DPs */
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__u32 backlog;
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__u32 qave;
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__u32 forced;
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__u32 early;
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__u32 other;
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__u32 pdrop;
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unsigned char Wlog; /* log(W) */
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unsigned char Plog; /* log(P_max/(qth_max-qth_min)) */
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unsigned char Scell_log; /* cell size for idle damping */
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__u8 prio; /* prio of this VQ */
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__u32 packets;
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__u32 bytesin;
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__u32 limit; /* HARD maximal queue length (bytes) */
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__u32 qth_min; /* Min average length threshold (bytes) */
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__u32 qth_max; /* Max average length threshold (bytes) */
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__u32 DP; /* upto 2^32 DPs */
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__u32 backlog;
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__u32 qave;
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__u32 forced;
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__u32 early;
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__u32 other;
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__u32 pdrop;
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__u8 Wlog; /* log(W) */
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__u8 Plog; /* log(P_max/(qth_max-qth_min)) */
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__u8 Scell_log; /* cell size for idle damping */
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__u8 prio; /* prio of this VQ */
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__u32 packets;
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__u32 bytesin;
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};
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/* gred setup */
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struct tc_gred_sopt
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{
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__u32 DPs;
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__u32 def_DP;
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__u8 grio;
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__u8 pad1;
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__u16 pad2;
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__u32 DPs;
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__u32 def_DP;
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__u8 grio;
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__u8 flags;
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__u16 pad1;
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};
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/* HTB section */
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@ -2,6 +2,7 @@
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#define _INET_ECN_H_
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#include <linux/ip.h>
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#include <linux/skbuff.h>
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#include <net/dsfield.h>
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enum {
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@ -48,7 +49,7 @@ static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
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(label) |= __constant_htons(INET_ECN_ECT_0 << 4); \
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} while (0)
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static inline void IP_ECN_set_ce(struct iphdr *iph)
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static inline int IP_ECN_set_ce(struct iphdr *iph)
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{
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u32 check = iph->check;
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u32 ecn = (iph->tos + 1) & INET_ECN_MASK;
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@ -61,7 +62,7 @@ static inline void IP_ECN_set_ce(struct iphdr *iph)
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* INET_ECN_CE => 00
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*/
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if (!(ecn & 2))
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return;
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return !ecn;
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/*
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* The following gives us:
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@ -72,6 +73,7 @@ static inline void IP_ECN_set_ce(struct iphdr *iph)
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iph->check = check + (check>=0xFFFF);
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iph->tos |= INET_ECN_CE;
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return 1;
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}
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static inline void IP_ECN_clear(struct iphdr *iph)
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@ -87,11 +89,12 @@ static inline void ipv4_copy_dscp(struct iphdr *outer, struct iphdr *inner)
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struct ipv6hdr;
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static inline void IP6_ECN_set_ce(struct ipv6hdr *iph)
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static inline int IP6_ECN_set_ce(struct ipv6hdr *iph)
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{
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if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
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return;
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return 0;
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*(u32*)iph |= htonl(INET_ECN_CE << 20);
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return 1;
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}
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static inline void IP6_ECN_clear(struct ipv6hdr *iph)
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@ -105,4 +108,21 @@ static inline void ipv6_copy_dscp(struct ipv6hdr *outer, struct ipv6hdr *inner)
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ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);
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}
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static inline int INET_ECN_set_ce(struct sk_buff *skb)
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{
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switch (skb->protocol) {
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case __constant_htons(ETH_P_IP):
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if (skb->nh.raw + sizeof(struct iphdr) <= skb->tail)
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return IP_ECN_set_ce(skb->nh.iph);
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break;
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case __constant_htons(ETH_P_IPV6):
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if (skb->nh.raw + sizeof(struct ipv6hdr) <= skb->tail)
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return IP6_ECN_set_ce(skb->nh.ipv6h);
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break;
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}
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return 0;
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}
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#endif
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325
include/net/red.h
Normal file
325
include/net/red.h
Normal file
@ -0,0 +1,325 @@
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#ifndef __NET_SCHED_RED_H
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#define __NET_SCHED_RED_H
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#include <linux/config.h>
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#include <linux/types.h>
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#include <net/pkt_sched.h>
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#include <net/inet_ecn.h>
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#include <net/dsfield.h>
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/* Random Early Detection (RED) algorithm.
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=======================================
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Source: Sally Floyd and Van Jacobson, "Random Early Detection Gateways
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for Congestion Avoidance", 1993, IEEE/ACM Transactions on Networking.
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This file codes a "divisionless" version of RED algorithm
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as written down in Fig.17 of the paper.
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Short description.
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------------------
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When a new packet arrives we calculate the average queue length:
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avg = (1-W)*avg + W*current_queue_len,
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W is the filter time constant (chosen as 2^(-Wlog)), it controls
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the inertia of the algorithm. To allow larger bursts, W should be
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decreased.
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if (avg > th_max) -> packet marked (dropped).
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if (avg < th_min) -> packet passes.
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if (th_min < avg < th_max) we calculate probability:
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Pb = max_P * (avg - th_min)/(th_max-th_min)
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and mark (drop) packet with this probability.
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Pb changes from 0 (at avg==th_min) to max_P (avg==th_max).
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max_P should be small (not 1), usually 0.01..0.02 is good value.
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max_P is chosen as a number, so that max_P/(th_max-th_min)
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is a negative power of two in order arithmetics to contain
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only shifts.
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Parameters, settable by user:
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-----------------------------
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qth_min - bytes (should be < qth_max/2)
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qth_max - bytes (should be at least 2*qth_min and less limit)
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Wlog - bits (<32) log(1/W).
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Plog - bits (<32)
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Plog is related to max_P by formula:
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max_P = (qth_max-qth_min)/2^Plog;
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F.e. if qth_max=128K and qth_min=32K, then Plog=22
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corresponds to max_P=0.02
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Scell_log
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Stab
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Lookup table for log((1-W)^(t/t_ave).
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NOTES:
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Upper bound on W.
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-----------------
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If you want to allow bursts of L packets of size S,
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you should choose W:
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L + 1 - th_min/S < (1-(1-W)^L)/W
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th_min/S = 32 th_min/S = 4
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log(W) L
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-1 33
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-2 35
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-3 39
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-4 46
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-5 57
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-6 75
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-7 101
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-8 135
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-9 190
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etc.
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*/
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#define RED_STAB_SIZE 256
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#define RED_STAB_MASK (RED_STAB_SIZE - 1)
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struct red_stats
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{
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u32 prob_drop; /* Early probability drops */
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u32 prob_mark; /* Early probability marks */
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u32 forced_drop; /* Forced drops, qavg > max_thresh */
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u32 forced_mark; /* Forced marks, qavg > max_thresh */
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u32 pdrop; /* Drops due to queue limits */
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u32 other; /* Drops due to drop() calls */
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u32 backlog;
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};
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struct red_parms
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{
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/* Parameters */
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u32 qth_min; /* Min avg length threshold: A scaled */
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u32 qth_max; /* Max avg length threshold: A scaled */
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u32 Scell_max;
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u32 Rmask; /* Cached random mask, see red_rmask */
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u8 Scell_log;
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u8 Wlog; /* log(W) */
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u8 Plog; /* random number bits */
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u8 Stab[RED_STAB_SIZE];
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/* Variables */
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int qcount; /* Number of packets since last random
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number generation */
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u32 qR; /* Cached random number */
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unsigned long qavg; /* Average queue length: A scaled */
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psched_time_t qidlestart; /* Start of current idle period */
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};
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static inline u32 red_rmask(u8 Plog)
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{
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return Plog < 32 ? ((1 << Plog) - 1) : ~0UL;
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}
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static inline void red_set_parms(struct red_parms *p,
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u32 qth_min, u32 qth_max, u8 Wlog, u8 Plog,
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u8 Scell_log, u8 *stab)
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{
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/* Reset average queue length, the value is strictly bound
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* to the parameters below, reseting hurts a bit but leaving
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* it might result in an unreasonable qavg for a while. --TGR
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*/
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p->qavg = 0;
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p->qcount = -1;
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p->qth_min = qth_min << Wlog;
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p->qth_max = qth_max << Wlog;
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p->Wlog = Wlog;
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p->Plog = Plog;
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p->Rmask = red_rmask(Plog);
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p->Scell_log = Scell_log;
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p->Scell_max = (255 << Scell_log);
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memcpy(p->Stab, stab, sizeof(p->Stab));
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}
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static inline int red_is_idling(struct red_parms *p)
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{
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return !PSCHED_IS_PASTPERFECT(p->qidlestart);
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}
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static inline void red_start_of_idle_period(struct red_parms *p)
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{
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PSCHED_GET_TIME(p->qidlestart);
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}
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static inline void red_end_of_idle_period(struct red_parms *p)
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{
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PSCHED_SET_PASTPERFECT(p->qidlestart);
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}
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static inline void red_restart(struct red_parms *p)
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{
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red_end_of_idle_period(p);
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p->qavg = 0;
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p->qcount = -1;
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}
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static inline unsigned long red_calc_qavg_from_idle_time(struct red_parms *p)
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{
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psched_time_t now;
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long us_idle;
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int shift;
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PSCHED_GET_TIME(now);
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us_idle = PSCHED_TDIFF_SAFE(now, p->qidlestart, p->Scell_max);
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/*
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* The problem: ideally, average length queue recalcultion should
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* be done over constant clock intervals. This is too expensive, so
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* that the calculation is driven by outgoing packets.
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* When the queue is idle we have to model this clock by hand.
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*
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* SF+VJ proposed to "generate":
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*
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* m = idletime / (average_pkt_size / bandwidth)
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*
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* dummy packets as a burst after idle time, i.e.
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*
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* p->qavg *= (1-W)^m
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*
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* This is an apparently overcomplicated solution (f.e. we have to
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* precompute a table to make this calculation in reasonable time)
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* I believe that a simpler model may be used here,
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* but it is field for experiments.
|
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*/
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shift = p->Stab[(us_idle >> p->Scell_log) & RED_STAB_MASK];
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if (shift)
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return p->qavg >> shift;
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else {
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/* Approximate initial part of exponent with linear function:
|
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*
|
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* (1-W)^m ~= 1-mW + ...
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*
|
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* Seems, it is the best solution to
|
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* problem of too coarse exponent tabulation.
|
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*/
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us_idle = (p->qavg * us_idle) >> p->Scell_log;
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|
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if (us_idle < (p->qavg >> 1))
|
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return p->qavg - us_idle;
|
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else
|
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return p->qavg >> 1;
|
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}
|
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}
|
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|
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static inline unsigned long red_calc_qavg_no_idle_time(struct red_parms *p,
|
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unsigned int backlog)
|
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{
|
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/*
|
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* NOTE: p->qavg is fixed point number with point at Wlog.
|
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* The formula below is equvalent to floating point
|
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* version:
|
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*
|
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* qavg = qavg*(1-W) + backlog*W;
|
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*
|
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* --ANK (980924)
|
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*/
|
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return p->qavg + (backlog - (p->qavg >> p->Wlog));
|
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}
|
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|
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static inline unsigned long red_calc_qavg(struct red_parms *p,
|
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unsigned int backlog)
|
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{
|
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if (!red_is_idling(p))
|
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return red_calc_qavg_no_idle_time(p, backlog);
|
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else
|
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return red_calc_qavg_from_idle_time(p);
|
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}
|
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|
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static inline u32 red_random(struct red_parms *p)
|
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{
|
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return net_random() & p->Rmask;
|
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}
|
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|
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static inline int red_mark_probability(struct red_parms *p, unsigned long qavg)
|
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{
|
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/* The formula used below causes questions.
|
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|
||||
OK. qR is random number in the interval 0..Rmask
|
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i.e. 0..(2^Plog). If we used floating point
|
||||
arithmetics, it would be: (2^Plog)*rnd_num,
|
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where rnd_num is less 1.
|
||||
|
||||
Taking into account, that qavg have fixed
|
||||
point at Wlog, and Plog is related to max_P by
|
||||
max_P = (qth_max-qth_min)/2^Plog; two lines
|
||||
below have the following floating point equivalent:
|
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|
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max_P*(qavg - qth_min)/(qth_max-qth_min) < rnd/qcount
|
||||
|
||||
Any questions? --ANK (980924)
|
||||
*/
|
||||
return !(((qavg - p->qth_min) >> p->Wlog) * p->qcount < p->qR);
|
||||
}
|
||||
|
||||
enum {
|
||||
RED_BELOW_MIN_THRESH,
|
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RED_BETWEEN_TRESH,
|
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RED_ABOVE_MAX_TRESH,
|
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};
|
||||
|
||||
static inline int red_cmp_thresh(struct red_parms *p, unsigned long qavg)
|
||||
{
|
||||
if (qavg < p->qth_min)
|
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return RED_BELOW_MIN_THRESH;
|
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else if (qavg >= p->qth_max)
|
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return RED_ABOVE_MAX_TRESH;
|
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else
|
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return RED_BETWEEN_TRESH;
|
||||
}
|
||||
|
||||
enum {
|
||||
RED_DONT_MARK,
|
||||
RED_PROB_MARK,
|
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RED_HARD_MARK,
|
||||
};
|
||||
|
||||
static inline int red_action(struct red_parms *p, unsigned long qavg)
|
||||
{
|
||||
switch (red_cmp_thresh(p, qavg)) {
|
||||
case RED_BELOW_MIN_THRESH:
|
||||
p->qcount = -1;
|
||||
return RED_DONT_MARK;
|
||||
|
||||
case RED_BETWEEN_TRESH:
|
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if (++p->qcount) {
|
||||
if (red_mark_probability(p, qavg)) {
|
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p->qcount = 0;
|
||||
p->qR = red_random(p);
|
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return RED_PROB_MARK;
|
||||
}
|
||||
} else
|
||||
p->qR = red_random(p);
|
||||
|
||||
return RED_DONT_MARK;
|
||||
|
||||
case RED_ABOVE_MAX_TRESH:
|
||||
p->qcount = -1;
|
||||
return RED_HARD_MARK;
|
||||
}
|
||||
|
||||
BUG();
|
||||
return RED_DONT_MARK;
|
||||
}
|
||||
|
||||
#endif
|
||||
File diff suppressed because it is too large
Load Diff
@ -9,76 +9,23 @@
|
||||
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
|
||||
*
|
||||
* Changes:
|
||||
* J Hadi Salim <hadi@nortel.com> 980914: computation fixes
|
||||
* J Hadi Salim 980914: computation fixes
|
||||
* Alexey Makarenko <makar@phoenix.kharkov.ua> 990814: qave on idle link was calculated incorrectly.
|
||||
* J Hadi Salim <hadi@nortelnetworks.com> 980816: ECN support
|
||||
* J Hadi Salim 980816: ECN support
|
||||
*/
|
||||
|
||||
#include <linux/config.h>
|
||||
#include <linux/module.h>
|
||||
#include <asm/uaccess.h>
|
||||
#include <asm/system.h>
|
||||
#include <linux/bitops.h>
|
||||
#include <linux/types.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/sched.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/if_ether.h>
|
||||
#include <linux/inet.h>
|
||||
#include <linux/netdevice.h>
|
||||
#include <linux/etherdevice.h>
|
||||
#include <linux/notifier.h>
|
||||
#include <net/ip.h>
|
||||
#include <net/route.h>
|
||||
#include <linux/skbuff.h>
|
||||
#include <net/sock.h>
|
||||
#include <net/pkt_sched.h>
|
||||
#include <net/inet_ecn.h>
|
||||
#include <net/dsfield.h>
|
||||
#include <net/red.h>
|
||||
|
||||
|
||||
/* Random Early Detection (RED) algorithm.
|
||||
=======================================
|
||||
|
||||
Source: Sally Floyd and Van Jacobson, "Random Early Detection Gateways
|
||||
for Congestion Avoidance", 1993, IEEE/ACM Transactions on Networking.
|
||||
|
||||
This file codes a "divisionless" version of RED algorithm
|
||||
as written down in Fig.17 of the paper.
|
||||
|
||||
Short description.
|
||||
------------------
|
||||
|
||||
When a new packet arrives we calculate the average queue length:
|
||||
|
||||
avg = (1-W)*avg + W*current_queue_len,
|
||||
|
||||
W is the filter time constant (chosen as 2^(-Wlog)), it controls
|
||||
the inertia of the algorithm. To allow larger bursts, W should be
|
||||
decreased.
|
||||
|
||||
if (avg > th_max) -> packet marked (dropped).
|
||||
if (avg < th_min) -> packet passes.
|
||||
if (th_min < avg < th_max) we calculate probability:
|
||||
|
||||
Pb = max_P * (avg - th_min)/(th_max-th_min)
|
||||
|
||||
and mark (drop) packet with this probability.
|
||||
Pb changes from 0 (at avg==th_min) to max_P (avg==th_max).
|
||||
max_P should be small (not 1), usually 0.01..0.02 is good value.
|
||||
|
||||
max_P is chosen as a number, so that max_P/(th_max-th_min)
|
||||
is a negative power of two in order arithmetics to contain
|
||||
only shifts.
|
||||
|
||||
|
||||
Parameters, settable by user:
|
||||
/* Parameters, settable by user:
|
||||
-----------------------------
|
||||
|
||||
limit - bytes (must be > qth_max + burst)
|
||||
@ -89,243 +36,93 @@ Short description.
|
||||
arbitrarily high (well, less than ram size)
|
||||
Really, this limit will never be reached
|
||||
if RED works correctly.
|
||||
|
||||
qth_min - bytes (should be < qth_max/2)
|
||||
qth_max - bytes (should be at least 2*qth_min and less limit)
|
||||
Wlog - bits (<32) log(1/W).
|
||||
Plog - bits (<32)
|
||||
|
||||
Plog is related to max_P by formula:
|
||||
|
||||
max_P = (qth_max-qth_min)/2^Plog;
|
||||
|
||||
F.e. if qth_max=128K and qth_min=32K, then Plog=22
|
||||
corresponds to max_P=0.02
|
||||
|
||||
Scell_log
|
||||
Stab
|
||||
|
||||
Lookup table for log((1-W)^(t/t_ave).
|
||||
|
||||
|
||||
NOTES:
|
||||
|
||||
Upper bound on W.
|
||||
-----------------
|
||||
|
||||
If you want to allow bursts of L packets of size S,
|
||||
you should choose W:
|
||||
|
||||
L + 1 - th_min/S < (1-(1-W)^L)/W
|
||||
|
||||
th_min/S = 32 th_min/S = 4
|
||||
|
||||
log(W) L
|
||||
-1 33
|
||||
-2 35
|
||||
-3 39
|
||||
-4 46
|
||||
-5 57
|
||||
-6 75
|
||||
-7 101
|
||||
-8 135
|
||||
-9 190
|
||||
etc.
|
||||
*/
|
||||
|
||||
struct red_sched_data
|
||||
{
|
||||
/* Parameters */
|
||||
u32 limit; /* HARD maximal queue length */
|
||||
u32 qth_min; /* Min average length threshold: A scaled */
|
||||
u32 qth_max; /* Max average length threshold: A scaled */
|
||||
u32 Rmask;
|
||||
u32 Scell_max;
|
||||
unsigned char flags;
|
||||
char Wlog; /* log(W) */
|
||||
char Plog; /* random number bits */
|
||||
char Scell_log;
|
||||
u8 Stab[256];
|
||||
|
||||
/* Variables */
|
||||
unsigned long qave; /* Average queue length: A scaled */
|
||||
int qcount; /* Packets since last random number generation */
|
||||
u32 qR; /* Cached random number */
|
||||
|
||||
psched_time_t qidlestart; /* Start of idle period */
|
||||
struct tc_red_xstats st;
|
||||
u32 limit; /* HARD maximal queue length */
|
||||
unsigned char flags;
|
||||
struct red_parms parms;
|
||||
struct red_stats stats;
|
||||
};
|
||||
|
||||
static int red_ecn_mark(struct sk_buff *skb)
|
||||
static inline int red_use_ecn(struct red_sched_data *q)
|
||||
{
|
||||
if (skb->nh.raw + 20 > skb->tail)
|
||||
return 0;
|
||||
|
||||
switch (skb->protocol) {
|
||||
case __constant_htons(ETH_P_IP):
|
||||
if (INET_ECN_is_not_ect(skb->nh.iph->tos))
|
||||
return 0;
|
||||
IP_ECN_set_ce(skb->nh.iph);
|
||||
return 1;
|
||||
case __constant_htons(ETH_P_IPV6):
|
||||
if (INET_ECN_is_not_ect(ipv6_get_dsfield(skb->nh.ipv6h)))
|
||||
return 0;
|
||||
IP6_ECN_set_ce(skb->nh.ipv6h);
|
||||
return 1;
|
||||
default:
|
||||
return 0;
|
||||
}
|
||||
return q->flags & TC_RED_ECN;
|
||||
}
|
||||
|
||||
static int
|
||||
red_enqueue(struct sk_buff *skb, struct Qdisc* sch)
|
||||
static inline int red_use_harddrop(struct red_sched_data *q)
|
||||
{
|
||||
return q->flags & TC_RED_HARDDROP;
|
||||
}
|
||||
|
||||
static int red_enqueue(struct sk_buff *skb, struct Qdisc* sch)
|
||||
{
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
|
||||
psched_time_t now;
|
||||
q->parms.qavg = red_calc_qavg(&q->parms, sch->qstats.backlog);
|
||||
|
||||
if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
|
||||
long us_idle;
|
||||
int shift;
|
||||
if (red_is_idling(&q->parms))
|
||||
red_end_of_idle_period(&q->parms);
|
||||
|
||||
PSCHED_GET_TIME(now);
|
||||
us_idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
|
||||
PSCHED_SET_PASTPERFECT(q->qidlestart);
|
||||
switch (red_action(&q->parms, q->parms.qavg)) {
|
||||
case RED_DONT_MARK:
|
||||
break;
|
||||
|
||||
/*
|
||||
The problem: ideally, average length queue recalcultion should
|
||||
be done over constant clock intervals. This is too expensive, so that
|
||||
the calculation is driven by outgoing packets.
|
||||
When the queue is idle we have to model this clock by hand.
|
||||
case RED_PROB_MARK:
|
||||
sch->qstats.overlimits++;
|
||||
if (!red_use_ecn(q) || !INET_ECN_set_ce(skb)) {
|
||||
q->stats.prob_drop++;
|
||||
goto congestion_drop;
|
||||
}
|
||||
|
||||
SF+VJ proposed to "generate" m = idletime/(average_pkt_size/bandwidth)
|
||||
dummy packets as a burst after idle time, i.e.
|
||||
q->stats.prob_mark++;
|
||||
break;
|
||||
|
||||
q->qave *= (1-W)^m
|
||||
case RED_HARD_MARK:
|
||||
sch->qstats.overlimits++;
|
||||
if (red_use_harddrop(q) || !red_use_ecn(q) ||
|
||||
!INET_ECN_set_ce(skb)) {
|
||||
q->stats.forced_drop++;
|
||||
goto congestion_drop;
|
||||
}
|
||||
|
||||
This is an apparently overcomplicated solution (f.e. we have to precompute
|
||||
a table to make this calculation in reasonable time)
|
||||
I believe that a simpler model may be used here,
|
||||
but it is field for experiments.
|
||||
*/
|
||||
shift = q->Stab[us_idle>>q->Scell_log];
|
||||
|
||||
if (shift) {
|
||||
q->qave >>= shift;
|
||||
} else {
|
||||
/* Approximate initial part of exponent
|
||||
with linear function:
|
||||
(1-W)^m ~= 1-mW + ...
|
||||
|
||||
Seems, it is the best solution to
|
||||
problem of too coarce exponent tabulation.
|
||||
*/
|
||||
|
||||
us_idle = (q->qave * us_idle)>>q->Scell_log;
|
||||
if (us_idle < q->qave/2)
|
||||
q->qave -= us_idle;
|
||||
else
|
||||
q->qave >>= 1;
|
||||
}
|
||||
} else {
|
||||
q->qave += sch->qstats.backlog - (q->qave >> q->Wlog);
|
||||
/* NOTE:
|
||||
q->qave is fixed point number with point at Wlog.
|
||||
The formulae above is equvalent to floating point
|
||||
version:
|
||||
|
||||
qave = qave*(1-W) + sch->qstats.backlog*W;
|
||||
--ANK (980924)
|
||||
*/
|
||||
q->stats.forced_mark++;
|
||||
break;
|
||||
}
|
||||
|
||||
if (q->qave < q->qth_min) {
|
||||
q->qcount = -1;
|
||||
enqueue:
|
||||
if (sch->qstats.backlog + skb->len <= q->limit) {
|
||||
__skb_queue_tail(&sch->q, skb);
|
||||
sch->qstats.backlog += skb->len;
|
||||
sch->bstats.bytes += skb->len;
|
||||
sch->bstats.packets++;
|
||||
return NET_XMIT_SUCCESS;
|
||||
} else {
|
||||
q->st.pdrop++;
|
||||
}
|
||||
kfree_skb(skb);
|
||||
sch->qstats.drops++;
|
||||
return NET_XMIT_DROP;
|
||||
}
|
||||
if (q->qave >= q->qth_max) {
|
||||
q->qcount = -1;
|
||||
sch->qstats.overlimits++;
|
||||
mark:
|
||||
if (!(q->flags&TC_RED_ECN) || !red_ecn_mark(skb)) {
|
||||
q->st.early++;
|
||||
goto drop;
|
||||
}
|
||||
q->st.marked++;
|
||||
goto enqueue;
|
||||
}
|
||||
if (sch->qstats.backlog + skb->len <= q->limit)
|
||||
return qdisc_enqueue_tail(skb, sch);
|
||||
|
||||
if (++q->qcount) {
|
||||
/* The formula used below causes questions.
|
||||
q->stats.pdrop++;
|
||||
return qdisc_drop(skb, sch);
|
||||
|
||||
OK. qR is random number in the interval 0..Rmask
|
||||
i.e. 0..(2^Plog). If we used floating point
|
||||
arithmetics, it would be: (2^Plog)*rnd_num,
|
||||
where rnd_num is less 1.
|
||||
|
||||
Taking into account, that qave have fixed
|
||||
point at Wlog, and Plog is related to max_P by
|
||||
max_P = (qth_max-qth_min)/2^Plog; two lines
|
||||
below have the following floating point equivalent:
|
||||
|
||||
max_P*(qave - qth_min)/(qth_max-qth_min) < rnd/qcount
|
||||
|
||||
Any questions? --ANK (980924)
|
||||
*/
|
||||
if (((q->qave - q->qth_min)>>q->Wlog)*q->qcount < q->qR)
|
||||
goto enqueue;
|
||||
q->qcount = 0;
|
||||
q->qR = net_random()&q->Rmask;
|
||||
sch->qstats.overlimits++;
|
||||
goto mark;
|
||||
}
|
||||
q->qR = net_random()&q->Rmask;
|
||||
goto enqueue;
|
||||
|
||||
drop:
|
||||
kfree_skb(skb);
|
||||
sch->qstats.drops++;
|
||||
congestion_drop:
|
||||
qdisc_drop(skb, sch);
|
||||
return NET_XMIT_CN;
|
||||
}
|
||||
|
||||
static int
|
||||
red_requeue(struct sk_buff *skb, struct Qdisc* sch)
|
||||
static int red_requeue(struct sk_buff *skb, struct Qdisc* sch)
|
||||
{
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
|
||||
PSCHED_SET_PASTPERFECT(q->qidlestart);
|
||||
if (red_is_idling(&q->parms))
|
||||
red_end_of_idle_period(&q->parms);
|
||||
|
||||
__skb_queue_head(&sch->q, skb);
|
||||
sch->qstats.backlog += skb->len;
|
||||
sch->qstats.requeues++;
|
||||
return 0;
|
||||
return qdisc_requeue(skb, sch);
|
||||
}
|
||||
|
||||
static struct sk_buff *
|
||||
red_dequeue(struct Qdisc* sch)
|
||||
static struct sk_buff * red_dequeue(struct Qdisc* sch)
|
||||
{
|
||||
struct sk_buff *skb;
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
|
||||
skb = __skb_dequeue(&sch->q);
|
||||
if (skb) {
|
||||
sch->qstats.backlog -= skb->len;
|
||||
return skb;
|
||||
}
|
||||
PSCHED_GET_TIME(q->qidlestart);
|
||||
return NULL;
|
||||
skb = qdisc_dequeue_head(sch);
|
||||
|
||||
if (skb == NULL && !red_is_idling(&q->parms))
|
||||
red_start_of_idle_period(&q->parms);
|
||||
|
||||
return skb;
|
||||
}
|
||||
|
||||
static unsigned int red_drop(struct Qdisc* sch)
|
||||
@ -333,16 +130,17 @@ static unsigned int red_drop(struct Qdisc* sch)
|
||||
struct sk_buff *skb;
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
|
||||
skb = __skb_dequeue_tail(&sch->q);
|
||||
skb = qdisc_dequeue_tail(sch);
|
||||
if (skb) {
|
||||
unsigned int len = skb->len;
|
||||
sch->qstats.backlog -= len;
|
||||
sch->qstats.drops++;
|
||||
q->st.other++;
|
||||
kfree_skb(skb);
|
||||
q->stats.other++;
|
||||
qdisc_drop(skb, sch);
|
||||
return len;
|
||||
}
|
||||
PSCHED_GET_TIME(q->qidlestart);
|
||||
|
||||
if (!red_is_idling(&q->parms))
|
||||
red_start_of_idle_period(&q->parms);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -350,43 +148,38 @@ static void red_reset(struct Qdisc* sch)
|
||||
{
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
|
||||
__skb_queue_purge(&sch->q);
|
||||
sch->qstats.backlog = 0;
|
||||
PSCHED_SET_PASTPERFECT(q->qidlestart);
|
||||
q->qave = 0;
|
||||
q->qcount = -1;
|
||||
qdisc_reset_queue(sch);
|
||||
red_restart(&q->parms);
|
||||
}
|
||||
|
||||
static int red_change(struct Qdisc *sch, struct rtattr *opt)
|
||||
{
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
struct rtattr *tb[TCA_RED_STAB];
|
||||
struct rtattr *tb[TCA_RED_MAX];
|
||||
struct tc_red_qopt *ctl;
|
||||
|
||||
if (opt == NULL ||
|
||||
rtattr_parse_nested(tb, TCA_RED_STAB, opt) ||
|
||||
tb[TCA_RED_PARMS-1] == 0 || tb[TCA_RED_STAB-1] == 0 ||
|
||||
if (opt == NULL || rtattr_parse_nested(tb, TCA_RED_MAX, opt))
|
||||
return -EINVAL;
|
||||
|
||||
if (tb[TCA_RED_PARMS-1] == NULL ||
|
||||
RTA_PAYLOAD(tb[TCA_RED_PARMS-1]) < sizeof(*ctl) ||
|
||||
RTA_PAYLOAD(tb[TCA_RED_STAB-1]) < 256)
|
||||
tb[TCA_RED_STAB-1] == NULL ||
|
||||
RTA_PAYLOAD(tb[TCA_RED_STAB-1]) < RED_STAB_SIZE)
|
||||
return -EINVAL;
|
||||
|
||||
ctl = RTA_DATA(tb[TCA_RED_PARMS-1]);
|
||||
|
||||
sch_tree_lock(sch);
|
||||
q->flags = ctl->flags;
|
||||
q->Wlog = ctl->Wlog;
|
||||
q->Plog = ctl->Plog;
|
||||
q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
|
||||
q->Scell_log = ctl->Scell_log;
|
||||
q->Scell_max = (255<<q->Scell_log);
|
||||
q->qth_min = ctl->qth_min<<ctl->Wlog;
|
||||
q->qth_max = ctl->qth_max<<ctl->Wlog;
|
||||
q->limit = ctl->limit;
|
||||
memcpy(q->Stab, RTA_DATA(tb[TCA_RED_STAB-1]), 256);
|
||||
|
||||
q->qcount = -1;
|
||||
red_set_parms(&q->parms, ctl->qth_min, ctl->qth_max, ctl->Wlog,
|
||||
ctl->Plog, ctl->Scell_log,
|
||||
RTA_DATA(tb[TCA_RED_STAB-1]));
|
||||
|
||||
if (skb_queue_empty(&sch->q))
|
||||
PSCHED_SET_PASTPERFECT(q->qidlestart);
|
||||
red_end_of_idle_period(&q->parms);
|
||||
|
||||
sch_tree_unlock(sch);
|
||||
return 0;
|
||||
}
|
||||
@ -399,39 +192,39 @@ static int red_init(struct Qdisc* sch, struct rtattr *opt)
|
||||
static int red_dump(struct Qdisc *sch, struct sk_buff *skb)
|
||||
{
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
unsigned char *b = skb->tail;
|
||||
struct rtattr *rta;
|
||||
struct tc_red_qopt opt;
|
||||
struct rtattr *opts = NULL;
|
||||
struct tc_red_qopt opt = {
|
||||
.limit = q->limit,
|
||||
.flags = q->flags,
|
||||
.qth_min = q->parms.qth_min >> q->parms.Wlog,
|
||||
.qth_max = q->parms.qth_max >> q->parms.Wlog,
|
||||
.Wlog = q->parms.Wlog,
|
||||
.Plog = q->parms.Plog,
|
||||
.Scell_log = q->parms.Scell_log,
|
||||
};
|
||||
|
||||
rta = (struct rtattr*)b;
|
||||
RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
|
||||
opt.limit = q->limit;
|
||||
opt.qth_min = q->qth_min>>q->Wlog;
|
||||
opt.qth_max = q->qth_max>>q->Wlog;
|
||||
opt.Wlog = q->Wlog;
|
||||
opt.Plog = q->Plog;
|
||||
opt.Scell_log = q->Scell_log;
|
||||
opt.flags = q->flags;
|
||||
opts = RTA_NEST(skb, TCA_OPTIONS);
|
||||
RTA_PUT(skb, TCA_RED_PARMS, sizeof(opt), &opt);
|
||||
rta->rta_len = skb->tail - b;
|
||||
|
||||
return skb->len;
|
||||
return RTA_NEST_END(skb, opts);
|
||||
|
||||
rtattr_failure:
|
||||
skb_trim(skb, b - skb->data);
|
||||
return -1;
|
||||
return RTA_NEST_CANCEL(skb, opts);
|
||||
}
|
||||
|
||||
static int red_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
|
||||
{
|
||||
struct red_sched_data *q = qdisc_priv(sch);
|
||||
struct tc_red_xstats st = {
|
||||
.early = q->stats.prob_drop + q->stats.forced_drop,
|
||||
.pdrop = q->stats.pdrop,
|
||||
.other = q->stats.other,
|
||||
.marked = q->stats.prob_mark + q->stats.forced_mark,
|
||||
};
|
||||
|
||||
return gnet_stats_copy_app(d, &q->st, sizeof(q->st));
|
||||
return gnet_stats_copy_app(d, &st, sizeof(st));
|
||||
}
|
||||
|
||||
static struct Qdisc_ops red_qdisc_ops = {
|
||||
.next = NULL,
|
||||
.cl_ops = NULL,
|
||||
.id = "red",
|
||||
.priv_size = sizeof(struct red_sched_data),
|
||||
.enqueue = red_enqueue,
|
||||
@ -450,10 +243,13 @@ static int __init red_module_init(void)
|
||||
{
|
||||
return register_qdisc(&red_qdisc_ops);
|
||||
}
|
||||
static void __exit red_module_exit(void)
|
||||
|
||||
static void __exit red_module_exit(void)
|
||||
{
|
||||
unregister_qdisc(&red_qdisc_ops);
|
||||
}
|
||||
|
||||
module_init(red_module_init)
|
||||
module_exit(red_module_exit)
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
|
||||
Loading…
Reference in New Issue
Block a user