/*- * Copyright (C) 1998-2003 * Sony Computer Science Laboratories Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY SONY CSL AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL SONY CSL OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /*- * Copyright (c) 1990-1994 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the Computer Systems * Engineering Group at Lawrence Berkeley Laboratory. * 4. Neither the name of the University nor of the Laboratory may be used * to endorse or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $KAME: altq_rio.c,v 1.17 2003/07/10 12:07:49 kjc Exp $ */ #include "opt_altq.h" #include "opt_inet.h" #include "opt_inet6.h" #ifdef ALTQ_RIO /* rio is enabled by ALTQ_RIO option in opt_altq.h */ #include <sys/param.h> #include <sys/malloc.h> #include <sys/mbuf.h> #include <sys/socket.h> #include <sys/systm.h> #include <sys/errno.h> #if 1 /* ALTQ3_COMPAT */ #include <sys/proc.h> #include <sys/sockio.h> #include <sys/kernel.h> #endif #include <net/if.h> #include <net/if_var.h> #include <netinet/in.h> #include <netinet/in_systm.h> #include <netinet/ip.h> #ifdef INET6 #include <netinet/ip6.h> #endif #include <netpfil/pf/pf.h> #include <netpfil/pf/pf_altq.h> #include <net/altq/altq.h> #include <net/altq/altq_cdnr.h> #include <net/altq/altq_red.h> #include <net/altq/altq_rio.h> /* * RIO: RED with IN/OUT bit * described in * "Explicit Allocation of Best Effort Packet Delivery Service" * David D. Clark and Wenjia Fang, MIT Lab for Computer Science * http://diffserv.lcs.mit.edu/Papers/exp-alloc-ddc-wf.{ps,pdf} * * this implementation is extended to support more than 2 drop precedence * values as described in RFC2597 (Assured Forwarding PHB Group). * */ /* * AF DS (differentiated service) codepoints. * (classes can be mapped to CBQ or H-FSC classes.) * * 0 1 2 3 4 5 6 7 * +---+---+---+---+---+---+---+---+ * | CLASS |DropPre| 0 | CU | * +---+---+---+---+---+---+---+---+ * * class 1: 001 * class 2: 010 * class 3: 011 * class 4: 100 * * low drop prec: 01 * medium drop prec: 10 * high drop prec: 01 */ /* normal red parameters */ #define W_WEIGHT 512 /* inverse of weight of EWMA (511/512) */ /* q_weight = 0.00195 */ /* red parameters for a slow link */ #define W_WEIGHT_1 128 /* inverse of weight of EWMA (127/128) */ /* q_weight = 0.0078125 */ /* red parameters for a very slow link (e.g., dialup) */ #define W_WEIGHT_2 64 /* inverse of weight of EWMA (63/64) */ /* q_weight = 0.015625 */ /* fixed-point uses 12-bit decimal places */ #define FP_SHIFT 12 /* fixed-point shift */ /* red parameters for drop probability */ #define INV_P_MAX 10 /* inverse of max drop probability */ #define TH_MIN 5 /* min threshold */ #define TH_MAX 15 /* max threshold */ #define RIO_LIMIT 60 /* default max queue length */ #define RIO_STATS /* collect statistics */ #define TV_DELTA(a, b, delta) { \ int xxs; \ \ delta = (a)->tv_usec - (b)->tv_usec; \ if ((xxs = (a)->tv_sec - (b)->tv_sec) != 0) { \ if (xxs < 0) { \ delta = 60000000; \ } else if (xxs > 4) { \ if (xxs > 60) \ delta = 60000000; \ else \ delta += xxs * 1000000; \ } else while (xxs > 0) { \ delta += 1000000; \ xxs--; \ } \ } \ } /* default rio parameter values */ static struct redparams default_rio_params[RIO_NDROPPREC] = { /* th_min, th_max, inv_pmax */ { TH_MAX * 2 + TH_MIN, TH_MAX * 3, INV_P_MAX }, /* low drop precedence */ { TH_MAX + TH_MIN, TH_MAX * 2, INV_P_MAX }, /* medium drop precedence */ { TH_MIN, TH_MAX, INV_P_MAX } /* high drop precedence */ }; /* internal function prototypes */ static int dscp2index(u_int8_t); rio_t * rio_alloc(int weight, struct redparams *params, int flags, int pkttime) { rio_t *rp; int w, i; int npkts_per_sec; rp = malloc(sizeof(rio_t), M_DEVBUF, M_NOWAIT | M_ZERO); if (rp == NULL) return (NULL); rp->rio_flags = flags; if (pkttime == 0) /* default packet time: 1000 bytes / 10Mbps * 8 * 1000000 */ rp->rio_pkttime = 800; else rp->rio_pkttime = pkttime; if (weight != 0) rp->rio_weight = weight; else { /* use default */ rp->rio_weight = W_WEIGHT; /* when the link is very slow, adjust red parameters */ npkts_per_sec = 1000000 / rp->rio_pkttime; if (npkts_per_sec < 50) { /* up to about 400Kbps */ rp->rio_weight = W_WEIGHT_2; } else if (npkts_per_sec < 300) { /* up to about 2.4Mbps */ rp->rio_weight = W_WEIGHT_1; } } /* calculate wshift. weight must be power of 2 */ w = rp->rio_weight; for (i = 0; w > 1; i++) w = w >> 1; rp->rio_wshift = i; w = 1 << rp->rio_wshift; if (w != rp->rio_weight) { printf("invalid weight value %d for red! use %d\n", rp->rio_weight, w); rp->rio_weight = w; } /* allocate weight table */ rp->rio_wtab = wtab_alloc(rp->rio_weight); for (i = 0; i < RIO_NDROPPREC; i++) { struct dropprec_state *prec = &rp->rio_precstate[i]; prec->avg = 0; prec->idle = 1; if (params == NULL || params[i].inv_pmax == 0) prec->inv_pmax = default_rio_params[i].inv_pmax; else prec->inv_pmax = params[i].inv_pmax; if (params == NULL || params[i].th_min == 0) prec->th_min = default_rio_params[i].th_min; else prec->th_min = params[i].th_min; if (params == NULL || params[i].th_max == 0) prec->th_max = default_rio_params[i].th_max; else prec->th_max = params[i].th_max; /* * th_min_s and th_max_s are scaled versions of th_min * and th_max to be compared with avg. */ prec->th_min_s = prec->th_min << (rp->rio_wshift + FP_SHIFT); prec->th_max_s = prec->th_max << (rp->rio_wshift + FP_SHIFT); /* * precompute probability denominator * probd = (2 * (TH_MAX-TH_MIN) / pmax) in fixed-point */ prec->probd = (2 * (prec->th_max - prec->th_min) * prec->inv_pmax) << FP_SHIFT; microtime(&prec->last); } return (rp); } void rio_destroy(rio_t *rp) { wtab_destroy(rp->rio_wtab); free(rp, M_DEVBUF); } void rio_getstats(rio_t *rp, struct redstats *sp) { int i; for (i = 0; i < RIO_NDROPPREC; i++) { bcopy(&rp->q_stats[i], sp, sizeof(struct redstats)); sp->q_avg = rp->rio_precstate[i].avg >> rp->rio_wshift; sp++; } } #if (RIO_NDROPPREC == 3) /* * internally, a drop precedence value is converted to an index * starting from 0. */ static int dscp2index(u_int8_t dscp) { int dpindex = dscp & AF_DROPPRECMASK; if (dpindex == 0) return (0); return ((dpindex >> 3) - 1); } #endif #if 1 /* * kludge: when a packet is dequeued, we need to know its drop precedence * in order to keep the queue length of each drop precedence. * use m_pkthdr.rcvif to pass this info. */ #define RIOM_SET_PRECINDEX(m, idx) \ do { (m)->m_pkthdr.rcvif = (void *)((long)(idx)); } while (0) #define RIOM_GET_PRECINDEX(m) \ ({ long idx; idx = (long)((m)->m_pkthdr.rcvif); \ (m)->m_pkthdr.rcvif = NULL; idx; }) #endif int rio_addq(rio_t *rp, class_queue_t *q, struct mbuf *m, struct altq_pktattr *pktattr) { int avg, droptype; u_int8_t dsfield, odsfield; int dpindex, i, n, t; struct timeval now; struct dropprec_state *prec; dsfield = odsfield = read_dsfield(m, pktattr); dpindex = dscp2index(dsfield); /* * update avg of the precedence states whose drop precedence * is larger than or equal to the drop precedence of the packet */ now.tv_sec = 0; for (i = dpindex; i < RIO_NDROPPREC; i++) { prec = &rp->rio_precstate[i]; avg = prec->avg; if (prec->idle) { prec->idle = 0; if (now.tv_sec == 0) microtime(&now); t = (now.tv_sec - prec->last.tv_sec); if (t > 60) avg = 0; else { t = t * 1000000 + (now.tv_usec - prec->last.tv_usec); n = t / rp->rio_pkttime; /* calculate (avg = (1 - Wq)^n * avg) */ if (n > 0) avg = (avg >> FP_SHIFT) * pow_w(rp->rio_wtab, n); } } /* run estimator. (avg is scaled by WEIGHT in fixed-point) */ avg += (prec->qlen << FP_SHIFT) - (avg >> rp->rio_wshift); prec->avg = avg; /* save the new value */ /* * count keeps a tally of arriving traffic that has not * been dropped. */ prec->count++; } prec = &rp->rio_precstate[dpindex]; avg = prec->avg; /* see if we drop early */ droptype = DTYPE_NODROP; if (avg >= prec->th_min_s && prec->qlen > 1) { if (avg >= prec->th_max_s) { /* avg >= th_max: forced drop */ droptype = DTYPE_FORCED; } else if (prec->old == 0) { /* first exceeds th_min */ prec->count = 1; prec->old = 1; } else if (drop_early((avg - prec->th_min_s) >> rp->rio_wshift, prec->probd, prec->count)) { /* unforced drop by red */ droptype = DTYPE_EARLY; } } else { /* avg < th_min */ prec->old = 0; } /* * if the queue length hits the hard limit, it's a forced drop. */ if (droptype == DTYPE_NODROP && qlen(q) >= qlimit(q)) droptype = DTYPE_FORCED; if (droptype != DTYPE_NODROP) { /* always drop incoming packet (as opposed to randomdrop) */ for (i = dpindex; i < RIO_NDROPPREC; i++) rp->rio_precstate[i].count = 0; #ifdef RIO_STATS if (droptype == DTYPE_EARLY) rp->q_stats[dpindex].drop_unforced++; else rp->q_stats[dpindex].drop_forced++; PKTCNTR_ADD(&rp->q_stats[dpindex].drop_cnt, m_pktlen(m)); #endif m_freem(m); return (-1); } for (i = dpindex; i < RIO_NDROPPREC; i++) rp->rio_precstate[i].qlen++; /* save drop precedence index in mbuf hdr */ RIOM_SET_PRECINDEX(m, dpindex); if (rp->rio_flags & RIOF_CLEARDSCP) dsfield &= ~DSCP_MASK; if (dsfield != odsfield) write_dsfield(m, pktattr, dsfield); _addq(q, m); #ifdef RIO_STATS PKTCNTR_ADD(&rp->q_stats[dpindex].xmit_cnt, m_pktlen(m)); #endif return (0); } struct mbuf * rio_getq(rio_t *rp, class_queue_t *q) { struct mbuf *m; int dpindex, i; if ((m = _getq(q)) == NULL) return NULL; dpindex = RIOM_GET_PRECINDEX(m); for (i = dpindex; i < RIO_NDROPPREC; i++) { if (--rp->rio_precstate[i].qlen == 0) { if (rp->rio_precstate[i].idle == 0) { rp->rio_precstate[i].idle = 1; microtime(&rp->rio_precstate[i].last); } } } return (m); } #endif /* ALTQ_RIO */
