Date: Wed, 22 Oct 2008 00:03:51 +0000 (UTC) From: Lawrence Stewart <lstewart@FreeBSD.org> To: src-committers@freebsd.org, svn-src-projects@freebsd.org Subject: svn commit: r184147 - in projects/tcp_cc_7.x/sys: . conf netinet Message-ID: <200810220003.m9M03ptx012021@svn.freebsd.org>
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Author: lstewart Date: Wed Oct 22 00:03:51 2008 New Revision: 184147 URL: http://svn.freebsd.org/changeset/base/184147 Log: Initial merge from the 8.x patch branch to create the 7.x version of the patch. Some minor tweaks were required to massage the patch into the 7.x tree. Added: projects/tcp_cc_7.x/sys/netinet/cc.c - copied unchanged from r184025, projects/tcp_cc_8.x/sys/netinet/cc.c projects/tcp_cc_7.x/sys/netinet/cc.h - copied, changed from r184025, projects/tcp_cc_8.x/sys/netinet/cc.h Modified: projects/tcp_cc_7.x/sys/ (props changed) projects/tcp_cc_7.x/sys/conf/files projects/tcp_cc_7.x/sys/netinet/tcp_input.c projects/tcp_cc_7.x/sys/netinet/tcp_output.c projects/tcp_cc_7.x/sys/netinet/tcp_subr.c projects/tcp_cc_7.x/sys/netinet/tcp_timer.c projects/tcp_cc_7.x/sys/netinet/tcp_usrreq.c projects/tcp_cc_7.x/sys/netinet/tcp_var.h Modified: projects/tcp_cc_7.x/sys/conf/files ============================================================================== --- projects/tcp_cc_7.x/sys/conf/files Wed Oct 22 00:01:53 2008 (r184146) +++ projects/tcp_cc_7.x/sys/conf/files Wed Oct 22 00:03:51 2008 (r184147) @@ -1794,6 +1794,7 @@ netinet/ip_mroute.c optional mrouting i netinet/ip_options.c optional inet netinet/ip_output.c optional inet netinet/raw_ip.c optional inet +netinet/cc.c optional inet netinet/sctp_asconf.c optional inet sctp netinet/sctp_auth.c optional inet sctp netinet/sctp_bsd_addr.c optional inet sctp Copied: projects/tcp_cc_7.x/sys/netinet/cc.c (from r184025, projects/tcp_cc_8.x/sys/netinet/cc.c) ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ projects/tcp_cc_7.x/sys/netinet/cc.c Wed Oct 22 00:03:51 2008 (r184147, copy of r184025, projects/tcp_cc_8.x/sys/netinet/cc.c) @@ -0,0 +1,451 @@ +/*- + * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1994, 1995 + * The Regents of the University of California. + * Copyright (c) 2008 Swinburne University of Technology, Melbourne, Australia + * All rights reserved. + * + * The majority of this software was developed at the Centre for + * Advanced Internet Architectures, Swinburne University, by Lawrence Stewart + * and James Healy, made possible in part by a grant from the Cisco University + * Research Program Fund at Community Foundation Silicon Valley. + * + * 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 THE AUTHOR 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 AUTHOR 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/libkern.h> +#include <sys/lock.h> +#include <sys/rwlock.h> +#include <sys/mutex.h> +#include <sys/socket.h> +#include <sys/socketvar.h> +#include <sys/sysctl.h> +#include <sys/malloc.h> +#include <sys/kernel.h> +#include <sys/sbuf.h> + +#include <netinet/in.h> +#include <netinet/in_pcb.h> +#include <netinet/tcp.h> +#include <netinet/tcp_seq.h> +#include <netinet/tcp_fsm.h> +#include <netinet/cc.h> + + +/* list of available cc algorithms on the current system */ +struct cc_head cc_list = STAILQ_HEAD_INITIALIZER(cc_list); + +struct rwlock cc_list_lock; + +MALLOC_DECLARE(M_STRING); +MALLOC_DEFINE(M_STRING, "string", "a string"); + +/* create a struct to point to our newreno functions */ +struct cc_algo newreno_cc_algo = { + .name = "newreno", + .init = newreno_init, + .deinit = NULL, + .cwnd_init = newreno_cwnd_init, + .ack_received = newreno_ack_received, + .pre_fr = newreno_pre_fr, + .post_fr = newreno_post_fr, + .after_idle = newreno_after_idle, + .after_timeout = newreno_after_timeout +}; + +/* the system wide default cc algorithm */ +char cc_algorithm[TCP_CA_NAME_MAX]; + +/* + * sysctl handler that allows the default cc algorithm for the system to be + * viewed and changed + */ +static int +cc_default_algorithm(SYSCTL_HANDLER_ARGS) +{ + struct cc_algo *funcs; + + if (!req->newptr) + goto skip; + + CC_LIST_RLOCK(); + STAILQ_FOREACH(funcs, &cc_list, entries) { + if (strncmp((char *)req->newptr, funcs->name, TCP_CA_NAME_MAX) == 0) + goto reorder; + } + CC_LIST_RUNLOCK(); + + return 1; + +reorder: + /* + * Make the selected system default cc algorithm + * the first element in the list if it isn't already + */ + CC_LIST_RUNLOCK(); + CC_LIST_WLOCK(); + if (funcs != STAILQ_FIRST(&cc_list)) { + STAILQ_REMOVE(&cc_list, funcs, cc_algo, entries); + STAILQ_INSERT_HEAD(&cc_list, funcs, entries); + } + CC_LIST_WUNLOCK(); + +skip: + return sysctl_handle_string(oidp, arg1, arg2, req); +} + +/* + * sysctl handler that displays the available cc algorithms as a read + * only value + */ +static int +cc_list_available(SYSCTL_HANDLER_ARGS) +{ + struct cc_algo *algo; + int error = 0, first = 1; + struct sbuf *s = NULL; + + if ((s = sbuf_new(NULL, NULL, TCP_CA_NAME_MAX, SBUF_AUTOEXTEND)) == NULL) + return -1; + + CC_LIST_RLOCK(); + STAILQ_FOREACH(algo, &cc_list, entries) { + error = sbuf_printf(s, (first) ? "%s" : ", %s", algo->name); + if (error != 0) + break; + first = 0; + } + CC_LIST_RUNLOCK(); + + if (!error) { + sbuf_finish(s); + error = sysctl_handle_string(oidp, sbuf_data(s), 1, req); + } + + sbuf_delete(s); + return error; +} + +/* + * Initialise cc on system boot + */ +void +cc_init() +{ + /* initialise the lock that will protect read/write access to our linked list */ + CC_LIST_LOCK_INIT(); + + /* initilize list of cc algorithms */ + STAILQ_INIT(&cc_list); + + /* add newreno to the list of available algorithms */ + cc_register_algorithm(&newreno_cc_algo); + + /* set newreno to the system default */ + strncpy(cc_algorithm, newreno_cc_algo.name, sizeof(cc_algorithm)); +} + +/* + * Returns 1 on success, 0 on failure + */ +int +cc_deregister_algorithm(struct cc_algo *remove_cc) +{ + struct cc_algo *funcs, *tmpfuncs; + register struct tcpcb *tp = NULL; + register struct inpcb *inp = NULL; + int success = 0; + + /* remove the algorithm from the list available to the system */ + CC_LIST_RLOCK(); + STAILQ_FOREACH_SAFE(funcs, &cc_list, entries, tmpfuncs) { + if (funcs == remove_cc) { + if (CC_LIST_TRY_WLOCK()) { + /* if this algorithm is the system default, reset the default to newreno */ + if (strncmp(cc_algorithm, remove_cc->name, TCP_CA_NAME_MAX) == 0) + snprintf(cc_algorithm, TCP_CA_NAME_MAX, "%s", newreno_cc_algo.name); + + STAILQ_REMOVE(&cc_list, funcs, cc_algo, entries); + success = 1; + CC_LIST_W2RLOCK(); + } + break; + } + } + CC_LIST_RUNLOCK(); + + if (success) { + /* + * check all active control blocks and change any that are using this + * algorithm back to newreno. If the algorithm that was in use requires + * deinit code to be run, call it + */ + INP_INFO_RLOCK(&tcbinfo); + LIST_FOREACH(inp, &tcb, inp_list) { + /* skip tcptw structs */ + if (inp->inp_vflag & INP_TIMEWAIT) + continue; + INP_WLOCK(inp); + if ((tp = intotcpcb(inp)) != NULL) { + if (strncmp(CC_ALGO(tp)->name, remove_cc->name, TCP_CA_NAME_MAX) == 0 ) { + tmpfuncs = CC_ALGO(tp); + CC_ALGO(tp) = &newreno_cc_algo; + /* + * XXX: We should stall here until + * we're sure the tcb has stopped + * using the deregistered algo's functions... + * Not sure how to do that yet! + */ + if(CC_ALGO(tp)->init) + CC_ALGO(tp)->init(tp); + if (tmpfuncs->deinit) + tmpfuncs->deinit(tp); + } + } + INP_WUNLOCK(inp); + } + INP_INFO_RUNLOCK(&tcbinfo); + } + + return success; +} + +int +cc_register_algorithm(struct cc_algo *add_cc) +{ + CC_LIST_WLOCK(); + STAILQ_INSERT_TAIL(&cc_list, add_cc, entries); + CC_LIST_WUNLOCK(); + return 1; +} + +/* + * NEW RENO + */ + +int +newreno_init(struct tcpcb *tp) +{ + printf("initialising tcp connection with newreno congestion control\n"); + return 0; +} + +/* + * update ssthresh to approx 1/2 of cwnd + */ +void +newreno_ssthresh_update(struct tcpcb *tp) +{ + u_int win; + + /* reset ssthresh */ + win = min(tp->snd_wnd, tp->snd_cwnd) / 2 / tp->t_maxseg; + + if (win < 2) + win = 2; + + tp->snd_ssthresh = win * tp->t_maxseg; +} + +/* + * initial cwnd at the start of a connection + * if there is a hostcache entry for the foreign host, base cwnd on that + * if rfc3390 is enabled, set cwnd to approx 4 MSS as recommended + * otherwise use the sysctl variables configured by the administrator + */ +void +newreno_cwnd_init(struct tcpcb *tp) +{ + struct hc_metrics_lite metrics; + struct inpcb *inp = tp->t_inpcb; + struct socket *so = inp->inp_socket; + + /* + * Set the slow-start flight size depending on whether this + * is a local network or not. + * + * Extend this so we cache the cwnd too and retrieve it here. + * Make cwnd even bigger than RFC3390 suggests but only if we + * have previous experience with the remote host. Be careful + * not make cwnd bigger than remote receive window or our own + * send socket buffer. Maybe put some additional upper bound + * on the retrieved cwnd. Should do incremental updates to + * hostcache when cwnd collapses so next connection doesn't + * overloads the path again. + * + * RFC3390 says only do this if SYN or SYN/ACK didn't got lost. + * We currently check only in syncache_socket for that. + */ + + tcp_hc_get(&inp->inp_inc, &metrics); + +#define TCP_METRICS_CWND +#ifdef TCP_METRICS_CWND + if (metrics.rmx_cwnd) + tp->snd_cwnd = max(tp->t_maxseg, + min(metrics.rmx_cwnd / 2, + min(tp->snd_wnd, so->so_snd.sb_hiwat))); + else +#endif + if (tcp_do_rfc3390) + tp->snd_cwnd = min(4 * tp->t_maxseg, max(2 * tp->t_maxseg, 4380)); +#ifdef INET6 + else if ((isipv6 && in6_localaddr(&inp->in6p_faddr)) || + (!isipv6 && in_localaddr(inp->inp_faddr))) +#else + else if (in_localaddr(inp->inp_faddr)) +#endif + tp->snd_cwnd = tp->t_maxseg * ss_fltsz_local; + else + tp->snd_cwnd = tp->t_maxseg * ss_fltsz; +} + +/* + * increase cwnd on receipt of a successful ACK + * if cwnd <= ssthresh, increases by 1 MSS per ACK + * if cwnd > ssthresh, increase by ~1 MSS per RTT + */ +void +newreno_ack_received(struct tcpcb *tp, struct tcphdr *th) +{ + u_int cw = tp->snd_cwnd; + u_int incr = tp->t_maxseg; + + if (cw > tp->snd_ssthresh) + incr = incr * incr / cw; + + tp->snd_cwnd = min(cw+incr, TCP_MAXWIN<<tp->snd_scale); +} + +/* + * update the value of ssthresh before entering FR + */ +void +newreno_pre_fr(struct tcpcb *tp, struct tcphdr *th) +{ + newreno_ssthresh_update(tp); +} + +/* + * decrease the cwnd in response to packet loss or a transmit timeout. + * th can be null, in which case cwnd will be set according to reno instead + * of new reno. + */ +void +newreno_post_fr(struct tcpcb *tp, struct tcphdr *th) +{ + /* + * Out of fast recovery. + * Window inflation should have left us + * with approximately snd_ssthresh + * outstanding data. + * But in case we would be inclined to + * send a burst, better to do it via + * the slow start mechanism. + */ + if (th && SEQ_GT(th->th_ack + tp->snd_ssthresh, tp->snd_max)) + tp->snd_cwnd = tp->snd_max - th->th_ack + tp->t_maxseg; + else + tp->snd_cwnd = tp->snd_ssthresh; +} + +/* + * if a connection has been idle for a while and more data is ready to be sent, + * reset cwnd + */ +void +newreno_after_idle(struct tcpcb *tp) +{ + /* + * We have been idle for "a while" and no acks are + * expected to clock out any data we send -- + * slow start to get ack "clock" running again. + * + * Set the slow-start flight size depending on whether + * this is a local network or not. + * + * Set the slow-start flight size depending on whether + * this is a local network or not. + */ + int ss = ss_fltsz; + +#ifdef INET6 + if (isipv6) { + if (in6_localaddr(&tp->t_inpcb->in6p_faddr)) + ss = ss_fltsz_local; + } else +#endif /* INET6 */ + + if (in_localaddr(tp->t_inpcb->inp_faddr)) + ss = ss_fltsz_local; + + tp->snd_cwnd = tp->t_maxseg * ss; +} + +/* + * reset the cwnd after a transmission timeout. + */ +void +newreno_after_timeout(struct tcpcb *tp) +{ + newreno_ssthresh_update(tp); + + /* + * Close the congestion window down to one segment + * (we'll open it by one segment for each ack we get). + * Since we probably have a window's worth of unacked + * data accumulated, this "slow start" keeps us from + * dumping all that data as back-to-back packets (which + * might overwhelm an intermediate gateway). + * + * There are two phases to the opening: Initially we + * open by one mss on each ack. This makes the window + * size increase exponentially with time. If the + * window is larger than the path can handle, this + * exponential growth results in dropped packet(s) + * almost immediately. To get more time between + * drops but still "push" the network to take advantage + * of improving conditions, we switch from exponential + * to linear window opening at some threshhold size. + * For a threshhold, we use half the current window + * size, truncated to a multiple of the mss. + * + * (the minimum cwnd that will give us exponential + * growth is 2 mss. We don't allow the threshhold + * to go below this.) + */ + tp->snd_cwnd = tp->t_maxseg; +} + +SYSCTL_NODE(_net_inet_tcp, OID_AUTO, cc, CTLFLAG_RW, NULL, + "congestion control related settings"); + +SYSCTL_PROC(_net_inet_tcp_cc, OID_AUTO, algorithm, CTLTYPE_STRING|CTLFLAG_RW, + &cc_algorithm, sizeof(cc_algorithm), cc_default_algorithm, "A", + "default congestion control algorithm"); + +SYSCTL_PROC(_net_inet_tcp_cc, OID_AUTO, available, CTLTYPE_STRING|CTLFLAG_RD, + NULL, 0, cc_list_available, "A", + "list available congestion control algorithms"); Copied and modified: projects/tcp_cc_7.x/sys/netinet/cc.h (from r184025, projects/tcp_cc_8.x/sys/netinet/cc.h) ============================================================================== --- projects/tcp_cc_8.x/sys/netinet/cc.h Sat Oct 18 07:20:45 2008 (r184025, copy source) +++ projects/tcp_cc_7.x/sys/netinet/cc.h Wed Oct 22 00:03:51 2008 (r184147) @@ -103,8 +103,14 @@ struct cc_algo { STAILQ_ENTRY(cc_algo) entries; }; -#define CC_ALGO(tp) ((tp)->cc_algo) -#define CC_DATA(tp) ((tp)->cc_data) +struct tcp_cc { + struct cc_algo *cc_algo; + void *cc_data; +}; + +#define CC_STRUCT(tp) ((tp)->t_pspare[2]) +#define CC_ALGO(tp) (((struct tcp_cc *)((tp)->t_pspare[2]))->cc_algo) +#define CC_DATA(tp) (((struct tcp_cc *)((tp)->t_pspare[2]))->cc_data) extern struct rwlock cc_list_lock; #define CC_LIST_LOCK_INIT() rw_init(&cc_list_lock, "cc_list") Modified: projects/tcp_cc_7.x/sys/netinet/tcp_input.c ============================================================================== --- projects/tcp_cc_7.x/sys/netinet/tcp_input.c Wed Oct 22 00:01:53 2008 (r184146) +++ projects/tcp_cc_7.x/sys/netinet/tcp_input.c Wed Oct 22 00:03:51 2008 (r184147) @@ -83,6 +83,7 @@ __FBSDID("$FreeBSD$"); #include <netinet6/tcp6_var.h> #include <netinet/tcpip.h> #include <netinet/tcp_syncache.h> +#include <netinet/cc.h> #ifdef TCPDEBUG #include <netinet/tcp_debug.h> #endif /* TCPDEBUG */ @@ -96,7 +97,7 @@ __FBSDID("$FreeBSD$"); #include <security/mac/mac_framework.h> -static const int tcprexmtthresh = 3; +const int tcprexmtthresh = 3; struct tcpstat tcpstat; SYSCTL_STRUCT(_net_inet_tcp, TCPCTL_STATS, stats, CTLFLAG_RW, @@ -123,7 +124,7 @@ static int tcp_do_rfc3042 = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3042, CTLFLAG_RW, &tcp_do_rfc3042, 0, "Enable RFC 3042 (Limited Transmit)"); -static int tcp_do_rfc3390 = 1; +int tcp_do_rfc3390 = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3390, CTLFLAG_RW, &tcp_do_rfc3390, 0, "Enable RFC 3390 (Increasing TCP's Initial Congestion Window)"); @@ -1017,14 +1018,9 @@ tcp_do_segment(struct mbuf *m, struct tc if (SEQ_GT(th->th_ack, tp->snd_una) && SEQ_LEQ(th->th_ack, tp->snd_max) && tp->snd_cwnd >= tp->snd_wnd && - ((!tcp_do_newreno && - !(tp->t_flags & TF_SACK_PERMIT) && - tp->t_dupacks < tcprexmtthresh) || - ((tcp_do_newreno || - (tp->t_flags & TF_SACK_PERMIT)) && - !IN_FASTRECOVERY(tp) && - (to.to_flags & TOF_SACK) == 0 && - TAILQ_EMPTY(&tp->snd_holes)))) { + !IN_FASTRECOVERY(tp) && + (to.to_flags & TOF_SACK) == 0 && + TAILQ_EMPTY(&tp->snd_holes)) { KASSERT(headlocked, ("%s: headlocked", __func__)); INP_INFO_WUNLOCK(&tcbinfo); @@ -1780,9 +1776,7 @@ tcp_do_segment(struct mbuf *m, struct tc th->th_ack != tp->snd_una) tp->t_dupacks = 0; else if (++tp->t_dupacks > tcprexmtthresh || - ((tcp_do_newreno || - (tp->t_flags & TF_SACK_PERMIT)) && - IN_FASTRECOVERY(tp))) { + IN_FASTRECOVERY(tp)) { if ((tp->t_flags & TF_SACK_PERMIT) && IN_FASTRECOVERY(tp)) { int awnd; @@ -1806,7 +1800,6 @@ tcp_do_segment(struct mbuf *m, struct tc goto drop; } else if (tp->t_dupacks == tcprexmtthresh) { tcp_seq onxt = tp->snd_nxt; - u_int win; /* * If we're doing sack, check to @@ -1820,18 +1813,22 @@ tcp_do_segment(struct mbuf *m, struct tc tp->t_dupacks = 0; break; } - } else if (tcp_do_newreno) { + } else { if (SEQ_LEQ(th->th_ack, tp->snd_recover)) { tp->t_dupacks = 0; break; } } - win = min(tp->snd_wnd, tp->snd_cwnd) / - 2 / tp->t_maxseg; - if (win < 2) - win = 2; - tp->snd_ssthresh = win * tp->t_maxseg; + + /* + * If the current tcp cc module has + * defined a hook for tasks to run + * before entering FR, call it + */ + if (CC_ALGO(tp)->pre_fr) + CC_ALGO(tp)->pre_fr(tp, th); + ENTER_FASTRECOVERY(tp); tp->snd_recover = tp->snd_max; tcp_timer_activate(tp, TT_REXMT, 0); @@ -1897,37 +1894,16 @@ tcp_do_segment(struct mbuf *m, struct tc * If the congestion window was inflated to account * for the other side's cached packets, retract it. */ - if (tcp_do_newreno || (tp->t_flags & TF_SACK_PERMIT)) { - if (IN_FASTRECOVERY(tp)) { - if (SEQ_LT(th->th_ack, tp->snd_recover)) { - if (tp->t_flags & TF_SACK_PERMIT) - tcp_sack_partialack(tp, th); - else - tcp_newreno_partial_ack(tp, th); - } else { - /* - * Out of fast recovery. - * Window inflation should have left us - * with approximately snd_ssthresh - * outstanding data. - * But in case we would be inclined to - * send a burst, better to do it via - * the slow start mechanism. - */ - if (SEQ_GT(th->th_ack + - tp->snd_ssthresh, - tp->snd_max)) - tp->snd_cwnd = tp->snd_max - - th->th_ack + - tp->t_maxseg; - else - tp->snd_cwnd = tp->snd_ssthresh; - } + if (IN_FASTRECOVERY(tp)) { + if (SEQ_LT(th->th_ack, tp->snd_recover)) { + if (tp->t_flags & TF_SACK_PERMIT) + tcp_sack_partialack(tp, th); + else + tcp_newreno_partial_ack(tp, th); + } else { + if (CC_ALGO(tp)->post_fr) + CC_ALGO(tp)->post_fr(tp, th); } - } else { - if (tp->t_dupacks >= tcprexmtthresh && - tp->snd_cwnd > tp->snd_ssthresh) - tp->snd_cwnd = tp->snd_ssthresh; } tp->t_dupacks = 0; /* @@ -2033,13 +2009,9 @@ process_ACK: * If cwnd > maxseg^2, fix the cwnd increment at 1 byte * to avoid capping cwnd (as suggested in RFC2581). */ - if ((!tcp_do_newreno && !(tp->t_flags & TF_SACK_PERMIT)) || - !IN_FASTRECOVERY(tp)) { - u_int cw = tp->snd_cwnd; - u_int incr = tp->t_maxseg; - if (cw > tp->snd_ssthresh) - incr = max((incr * incr / cw), 1); - tp->snd_cwnd = min(cw+incr, TCP_MAXWIN<<tp->snd_scale); + if (!IN_FASTRECOVERY(tp)) { + if (CC_ALGO(tp)->ack_received) + CC_ALGO(tp)->ack_received(tp, th); } SOCKBUF_LOCK(&so->so_snd); if (acked > so->so_snd.sb_cc) { @@ -2054,14 +2026,11 @@ process_ACK: /* NB: sowwakeup_locked() does an implicit unlock. */ sowwakeup_locked(so); /* Detect una wraparound. */ - if ((tcp_do_newreno || (tp->t_flags & TF_SACK_PERMIT)) && - !IN_FASTRECOVERY(tp) && + if (!IN_FASTRECOVERY(tp) && SEQ_GT(tp->snd_una, tp->snd_recover) && SEQ_LEQ(th->th_ack, tp->snd_recover)) tp->snd_recover = th->th_ack - 1; - if ((tcp_do_newreno || (tp->t_flags & TF_SACK_PERMIT)) && - IN_FASTRECOVERY(tp) && - SEQ_GEQ(th->th_ack, tp->snd_recover)) + if (IN_FASTRECOVERY(tp) && SEQ_GEQ(th->th_ack, tp->snd_recover)) EXIT_FASTRECOVERY(tp); tp->snd_una = th->th_ack; if (tp->t_flags & TF_SACK_PERMIT) { @@ -2940,41 +2909,11 @@ tcp_mss(struct tcpcb *tp, int offer) if (metrics.rmx_bandwidth) tp->snd_bandwidth = metrics.rmx_bandwidth; - /* - * Set the slow-start flight size depending on whether this - * is a local network or not. - * - * Extend this so we cache the cwnd too and retrieve it here. - * Make cwnd even bigger than RFC3390 suggests but only if we - * have previous experience with the remote host. Be careful - * not make cwnd bigger than remote receive window or our own - * send socket buffer. Maybe put some additional upper bound - * on the retrieved cwnd. Should do incremental updates to - * hostcache when cwnd collapses so next connection doesn't - * overloads the path again. - * - * RFC3390 says only do this if SYN or SYN/ACK didn't got lost. - * We currently check only in syncache_socket for that. - */ -#define TCP_METRICS_CWND -#ifdef TCP_METRICS_CWND - if (metrics.rmx_cwnd) - tp->snd_cwnd = max(mss, - min(metrics.rmx_cwnd / 2, - min(tp->snd_wnd, so->so_snd.sb_hiwat))); - else -#endif - if (tcp_do_rfc3390) - tp->snd_cwnd = min(4 * mss, max(2 * mss, 4380)); -#ifdef INET6 - else if ((isipv6 && in6_localaddr(&inp->in6p_faddr)) || - (!isipv6 && in_localaddr(inp->inp_faddr))) -#else - else if (in_localaddr(inp->inp_faddr)) -#endif - tp->snd_cwnd = mss * ss_fltsz_local; + /* set the initial cwnd value */ + if (CC_ALGO(tp)->cwnd_init) + CC_ALGO(tp)->cwnd_init(tp); else - tp->snd_cwnd = mss * ss_fltsz; + tp->snd_cwnd = mss; /* Check the interface for TSO capabilities. */ if (mtuflags & CSUM_TSO) Modified: projects/tcp_cc_7.x/sys/netinet/tcp_output.c ============================================================================== --- projects/tcp_cc_7.x/sys/netinet/tcp_output.c Wed Oct 22 00:01:53 2008 (r184146) +++ projects/tcp_cc_7.x/sys/netinet/tcp_output.c Wed Oct 22 00:03:51 2008 (r184147) @@ -70,6 +70,7 @@ __FBSDID("$FreeBSD$"); #include <netinet/tcp_timer.h> #include <netinet/tcp_var.h> #include <netinet/tcpip.h> +#include <netinet/cc.h> #ifdef TCPDEBUG #include <netinet/tcp_debug.h> #endif @@ -98,10 +99,6 @@ int ss_fltsz_local = 4; SYSCTL_INT(_net_inet_tcp, OID_AUTO, local_slowstart_flightsize, CTLFLAG_RW, &ss_fltsz_local, 1, "Slow start flight size for local networks"); -int tcp_do_newreno = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, newreno, CTLFLAG_RW, - &tcp_do_newreno, 0, "Enable NewReno Algorithms"); - int tcp_do_tso = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, tso, CTLFLAG_RW, &tcp_do_tso, 0, "Enable TCP Segmentation Offload"); @@ -162,24 +159,9 @@ tcp_output(struct tcpcb *tp) */ idle = (tp->t_flags & TF_LASTIDLE) || (tp->snd_max == tp->snd_una); if (idle && (ticks - tp->t_rcvtime) >= tp->t_rxtcur) { - /* - * We have been idle for "a while" and no acks are - * expected to clock out any data we send -- - * slow start to get ack "clock" running again. - * - * Set the slow-start flight size depending on whether - * this is a local network or not. - */ - int ss = ss_fltsz; -#ifdef INET6 - if (isipv6) { - if (in6_localaddr(&tp->t_inpcb->in6p_faddr)) - ss = ss_fltsz_local; - } else -#endif /* INET6 */ - if (in_localaddr(tp->t_inpcb->inp_faddr)) - ss = ss_fltsz_local; - tp->snd_cwnd = tp->t_maxseg * ss; + /* reset cwnd after a period of idleness */ + if (CC_ALGO(tp)->after_idle) + CC_ALGO(tp)->after_idle(tp); } tp->t_flags &= ~TF_LASTIDLE; if (idle) { Modified: projects/tcp_cc_7.x/sys/netinet/tcp_subr.c ============================================================================== --- projects/tcp_cc_7.x/sys/netinet/tcp_subr.c Wed Oct 22 00:01:53 2008 (r184146) +++ projects/tcp_cc_7.x/sys/netinet/tcp_subr.c Wed Oct 22 00:03:51 2008 (r184147) @@ -49,6 +49,8 @@ __FBSDID("$FreeBSD$"); #ifdef INET6 #include <sys/domain.h> #endif +#include <sys/lock.h> +#include <sys/rwlock.h> #include <sys/priv.h> #include <sys/proc.h> #include <sys/socket.h> @@ -86,6 +88,7 @@ __FBSDID("$FreeBSD$"); #include <netinet/tcp_var.h> #include <netinet/tcp_syncache.h> #include <netinet/tcp_offload.h> +#include <netinet/cc.h> #ifdef INET6 #include <netinet6/tcp6_var.h> #endif @@ -218,6 +221,7 @@ static void tcp_isn_tick(void *); struct tcpcb_mem { struct tcpcb tcb; struct tcp_timer tt; + struct tcp_cc cc; }; static uma_zone_t tcpcb_zone; @@ -268,6 +272,8 @@ tcp_init(void) tcp_inflight_rttthresh = TCPTV_INFLIGHT_RTTTHRESH; tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; + cc_init(); + INP_INFO_LOCK_INIT(&tcbinfo, "tcp"); LIST_INIT(&tcb); tcbinfo.ipi_listhead = &tcb; @@ -592,6 +598,23 @@ tcp_newtcpcb(struct inpcb *inp) if (tm == NULL) return (NULL); tp = &tm->tcb; + + /* + * use the current system default cc algorithm, which is always + * the first algorithm in cc_list + */ + CC_STRUCT(tp) = &tm->cc; + CC_LIST_RLOCK(); + CC_ALGO(tp) = STAILQ_FIRST(&cc_list); + CC_LIST_RUNLOCK(); + + /* if the cc module fails to init, stop building the control block */ + if (CC_ALGO(tp)->init(tp) > 0) { + uma_zfree(tcpcb_zone, CC_STRUCT(tp)); + uma_zfree(tcpcb_zone, tp); + return NULL; + } + tp->t_timers = &tm->tt; /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */ tp->t_maxseg = tp->t_maxopd = @@ -752,8 +775,13 @@ tcp_discardcb(struct tcpcb *tp) } /* Disconnect offload device, if any. */ tcp_offload_detach(tp); - tcp_free_sackholes(tp); + + /* Allow the cc algorithm in use for this cb to clean up after itself */ + if (CC_ALGO(tp)->deinit) + CC_ALGO(tp)->deinit(tp); + + CC_ALGO(tp) = NULL; inp->inp_ppcb = NULL; tp->t_inpcb = NULL; uma_zfree(tcpcb_zone, tp); Modified: projects/tcp_cc_7.x/sys/netinet/tcp_timer.c ============================================================================== --- projects/tcp_cc_7.x/sys/netinet/tcp_timer.c Wed Oct 22 00:01:53 2008 (r184146) +++ projects/tcp_cc_7.x/sys/netinet/tcp_timer.c Wed Oct 22 00:03:51 2008 (r184147) @@ -60,6 +60,7 @@ __FBSDID("$FreeBSD$"); #include <netinet/tcp_timer.h> #include <netinet/tcp_var.h> #include <netinet/tcpip.h> +#include <netinet/cc.h> #ifdef TCPDEBUG #include <netinet/tcp_debug.h> #endif @@ -518,38 +519,11 @@ tcp_timer_rexmt(void * xtp) * If timing a segment in this window, stop the timer. */ tp->t_rtttime = 0; - /* - * Close the congestion window down to one segment - * (we'll open it by one segment for each ack we get). - * Since we probably have a window's worth of unacked - * data accumulated, this "slow start" keeps us from - * dumping all that data as back-to-back packets (which - * might overwhelm an intermediate gateway). - * - * There are two phases to the opening: Initially we - * open by one mss on each ack. This makes the window - * size increase exponentially with time. If the - * window is larger than the path can handle, this - * exponential growth results in dropped packet(s) - * almost immediately. To get more time between - * drops but still "push" the network to take advantage - * of improving conditions, we switch from exponential - * to linear window opening at some threshhold size. - * For a threshhold, we use half the current window - * size, truncated to a multiple of the mss. - * - * (the minimum cwnd that will give us exponential - * growth is 2 mss. We don't allow the threshhold - * to go below this.) - */ - { - u_int win = min(tp->snd_wnd, tp->snd_cwnd) / 2 / tp->t_maxseg; - if (win < 2) - win = 2; - tp->snd_cwnd = tp->t_maxseg; - tp->snd_ssthresh = win * tp->t_maxseg; - tp->t_dupacks = 0; - } + + if (CC_ALGO(tp)->after_timeout) + CC_ALGO(tp)->after_timeout(tp); + + tp->t_dupacks = 0; EXIT_FASTRECOVERY(tp); (void) tcp_output(tp); Modified: projects/tcp_cc_7.x/sys/netinet/tcp_usrreq.c ============================================================================== --- projects/tcp_cc_7.x/sys/netinet/tcp_usrreq.c Wed Oct 22 00:01:53 2008 (r184146) +++ projects/tcp_cc_7.x/sys/netinet/tcp_usrreq.c Wed Oct 22 00:03:51 2008 (r184147) @@ -82,6 +82,7 @@ __FBSDID("$FreeBSD$"); #include <netinet/tcp_timer.h> #include <netinet/tcp_var.h> #include <netinet/tcpip.h> +#include <netinet/cc.h> #ifdef TCPDEBUG #include <netinet/tcp_debug.h> #endif @@ -1261,6 +1262,8 @@ tcp_ctloutput(struct socket *so, struct struct inpcb *inp; struct tcpcb *tp; struct tcp_info ti; + char buf[TCP_CA_NAME_MAX]; + struct cc_algo *cc_algo; error = 0; inp = sotoinpcb(so); @@ -1370,6 +1373,58 @@ tcp_ctloutput(struct socket *so, struct error = EINVAL; break; + case TCP_CONGESTION: + INP_WUNLOCK(inp); + bzero(buf, sizeof(buf)); + error = sooptcopyin(sopt, &buf, sizeof(buf), 1); + if (error) + break; + INP_WLOCK_RECHECK(inp); + /* + * We return EINVAL if we can't find the requested cc + * algo. We set error here and reset to 0 if found to + * simplify the error checking, + */ + error = EINVAL; + CC_LIST_RLOCK(); + STAILQ_FOREACH(cc_algo, &cc_list, entries) { + if ( strncmp(buf, + cc_algo->name, + TCP_CA_NAME_MAX) == 0) { + /* + * we've found the requested algo, + * so revert the EINVAL error condition. + */ + error = 0; + /* + * we hold a write lock over the tcb + * so it's safe to do these things + * without ordering concerns + */ + if (CC_ALGO(tp)->deinit) + CC_ALGO(tp)->deinit(tp); + CC_ALGO(tp) = cc_algo; + /* + * if something goes pear shaped + * initialising the new algo, + * fall back to newreno (which + * does not require initialisation) + */ + if (cc_algo->init(tp) > 0) { + CC_ALGO(tp) = &newreno_cc_algo; + /* + * the only reason init() should + * fail is because of malloc + */ + error = ENOMEM; + } + break; /* break the STAILQ_FOREACH */ + } + } + CC_LIST_RUNLOCK(); + INP_WUNLOCK(inp); + break; + default: INP_WUNLOCK(inp); error = ENOPROTOOPT; @@ -1413,6 +1468,12 @@ tcp_ctloutput(struct socket *so, struct INP_WUNLOCK(inp); error = sooptcopyout(sopt, &ti, sizeof ti); break; + case TCP_CONGESTION: + bzero(buf, sizeof(buf)); + memcpy(&(CC_ALGO(tp)->name), buf, TCP_CA_NAME_MAX); + INP_WUNLOCK(inp); + error = sooptcopyout(sopt, buf, TCP_CA_NAME_MAX); + break; default: INP_WUNLOCK(inp); error = ENOPROTOOPT; Modified: projects/tcp_cc_7.x/sys/netinet/tcp_var.h ============================================================================== --- projects/tcp_cc_7.x/sys/netinet/tcp_var.h Wed Oct 22 00:01:53 2008 (r184146) +++ projects/tcp_cc_7.x/sys/netinet/tcp_var.h Wed Oct 22 00:03:51 2008 (r184147) @@ -504,7 +504,7 @@ extern int tcp_log_in_vain; extern int tcp_mssdflt; /* XXX */ extern int tcp_minmss; extern int tcp_delack_enabled; -extern int tcp_do_newreno; +extern int tcp_do_rfc3390; extern int path_mtu_discovery; extern int ss_fltsz; extern int ss_fltsz_local;
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