[PATCH] Implementation of draft-ietf-tcpm-newcwv-06
Adrian Chadd
adrian at freebsd.org
Mon Jun 30 19:29:45 UTC 2014
Hi!
Cool! Would you mind throwing it into a bugzilla ticket so it's not
lost and it can be assigned for some review?
http://bugs.freebsd.org/submit/
Is there any benefit in hanging this state off of it as a pointer to
some other struct, rather than having it in the tcpcb? Is it always
going to be used?
Thanks!
-a
On 30 June 2014 10:04, Tom Jones <jones at sdf.org> wrote:
> Hello,
>
> Attached is a patch which implements draft-ietf-tcpm-newcwv-06, "Updating TCP
> to support Rate-Limited Traffic". The patch is a port of the Linux
> implementation by Raffaello Secchi with influence from Aris
> Angelogiannopoulos's patch set that was sent to the list earlier this year.
>
> --
> Tom | I don't see how we are going to build the dystopian megapoli
> @adventureloop | we were promised in 80s and early 90s cyberpunk fiction if
> adventurist.me | you guys keep complaining.
>
> Index: sys/conf/files
> ===================================================================
> --- sys/conf/files (revision 268040)
> +++ sys/conf/files (working copy)
> @@ -3380,6 +3380,7 @@ netinet/tcp_reass.c optional inet | inet6
> netinet/tcp_sack.c optional inet | inet6
> netinet/tcp_subr.c optional inet | inet6
> netinet/tcp_syncache.c optional inet | inet6
> +netinet/tcp_newcwv.c optional inet | inet6
> netinet/tcp_timer.c optional inet | inet6
> netinet/tcp_timewait.c optional inet | inet6
> netinet/tcp_usrreq.c optional inet | inet6
> Index: sys/netinet/tcp_input.c
> ===================================================================
> --- sys/netinet/tcp_input.c (revision 268040)
> +++ sys/netinet/tcp_input.c (working copy)
> @@ -105,6 +105,7 @@ __FBSDID("$FreeBSD$");
> #include <netinet6/tcp6_var.h>
> #include <netinet/tcpip.h>
> #include <netinet/tcp_syncache.h>
> +#include <netinet/tcp_newcwv.h>
> #ifdef TCPDEBUG
> #include <netinet/tcp_debug.h>
> #endif /* TCPDEBUG */
> @@ -174,6 +175,11 @@ SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, abc_l_var
> &VNET_NAME(tcp_abc_l_var), 2,
> "Cap the max cwnd increment during slow-start to this number of segments");
>
> +VNET_DEFINE(int, tcp_do_newcwv) = 0;
> +SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, newcwv, CTLFLAG_RW,
> + &VNET_NAME(tcp_do_newcwv), 0,
> + "Enable draft-ietf-tcpm-newcwv-06 (New Congestion Window Validation)");
> +
> static SYSCTL_NODE(_net_inet_tcp, OID_AUTO, ecn, CTLFLAG_RW, 0, "TCP ECN");
>
> VNET_DEFINE(int, tcp_do_ecn) = 0;
> @@ -309,6 +315,12 @@ cc_ack_received(struct tcpcb *tp, struct tcphdr *t
> tp->ccv->curack = th->th_ack;
> CC_ALGO(tp)->ack_received(tp->ccv, type);
> }
> +
> + /*
> + * update draft-ietf-newcwv-06 pipeack
> + */
> + if(V_tcp_do_newcwv && !IN_FASTRECOVERY(tp->t_flags))
> + tcp_newcwv_update_pipeack(tp);
> }
>
> static void inline
> @@ -378,6 +390,12 @@ cc_conn_init(struct tcpcb *tp)
> tp->snd_cwnd = 4 * tp->t_maxseg;
> }
>
> + /*
> + * Initialise NewCWV state
> + */
> + tp->init_cwnd = tp->snd_cwnd;
> + tcp_newcwv_reset(tp);
> +
> if (CC_ALGO(tp)->conn_init != NULL)
> CC_ALGO(tp)->conn_init(tp->ccv);
> }
> @@ -426,6 +444,11 @@ cc_cong_signal(struct tcpcb *tp, struct tcphdr *th
> tp->t_badrxtwin = 0;
> break;
> }
> +
> + if (V_tcp_do_newcwv &&
> + (type == CC_NDUPACK || type == CC_ECN) &&
> + tp->pipeack <= (tp->snd_cwnd >> 1) )
> + tcp_newcwv_enter_recovery(tp);
>
> if (CC_ALGO(tp)->cong_signal != NULL) {
> if (th != NULL)
> @@ -447,6 +470,13 @@ cc_post_recovery(struct tcpcb *tp, struct tcphdr *
> }
> /* XXXLAS: EXIT_RECOVERY ? */
> tp->t_bytes_acked = 0;
> +
> + if(V_tcp_do_newcwv) {
> + if(tp->loss_flight_size)
> + tcp_newcwv_end_recovery(tp);
> + tcp_newcwv_reset(tp);
> + }
> + tp->loss_flight_size = 0;
> }
>
> #ifdef TCP_SIGNATURE
> Index: sys/netinet/tcp_newcwv.c
> ===================================================================
> --- sys/netinet/tcp_newcwv.c (revision 0)
> +++ sys/netinet/tcp_newcwv.c (working copy)
> @@ -0,0 +1,174 @@
> +/*
> + * Copyright (c) 2014 Tom Jones <jones at sdf.org>
> + * 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 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>
> +
> +#include <sys/param.h>
> +#include <sys/kernel.h>
> +#include <sys/libkern.h>
> +#include <sys/socket.h>
> +#include <sys/socketvar.h>
> +
> +#include <netinet/tcp.h>
> +#include <netinet/tcp_var.h>
> +#include <netinet/tcp_newcwv.h>
> +
> +/*
> + * An implementation of NewCWV (draft-ietf-tcpm-newcwv-06) for FreeBSD.
> + * Based on the Linux implementation by Raffaello Secchi and the an initial
> + * implementation of draft-ietf-tcpm-newcwv-00 by Aris Angelogiannopoulos.
> + */
> +
> +#define nextbin(x) (((x)+1) & 0x03)
> +#define prevbin(x) (((x)-1) & 0x03)
> +
> +#define NCWV_UNDEF 0xFFFFFFFF
> +#define NCWV_FIVEMINS (300*hz)
> +
> +void add_element(struct tcpcb *,u_int32_t);
> +u_int32_t remove_expired_elements(struct tcpcb *);
> +
> +void
> +tcp_newcwv_update_pipeack(struct tcpcb *tp)
> +{
> + u_int32_t tmp_pipeack;
> + tp->psp = MAX(3 * tp->t_srtt,hz);
> +
> + if (tp->snd_una >= tp->prev_snd_nxt) {
> + /* get the pipeack sample */
> + tmp_pipeack = tp->snd_una - tp->prev_snd_una;
> +
> + tp->prev_snd_una = tp->snd_una;
> + tp->prev_snd_nxt = tp->snd_nxt;
> +
> + /* create a new element at the end of current pmp */
> + if(ticks > tp->time_stamp[tp->head] + (tp->psp >> 2))
> + add_element(tp,tmp_pipeack);
> + else
> + tp->psample[tp->head] = tmp_pipeack;
> + }
> +
> + tp->pipeack = remove_expired_elements(tp);
> +
> + /* check if cwnd is validated */
> + if (tp->pipeack == NCWV_UNDEF ||
> + ((tp->pipeack << 1) >= (tp->snd_cwnd * tp->t_maxseg))) {
> + tp->cwnd_valid_ts = ticks;
> + }
> +}
> +
> +void
> +add_element(struct tcpcb *tp,u_int32_t value)
> +{
> + tp->head = nextbin(tp->head);
> + tp->psample[tp->head] = value;
> + tp->time_stamp[tp->head] = ticks;
> +}
> +
> +u_int32_t
> +remove_expired_elements(struct tcpcb *tp)
> +{
> + uint8_t head = tp->head;
> + u_int32_t tmp = tp->psample[head];
> +
> + while(tp->psample[head] != NCWV_UNDEF) {
> + /* remove the element if expired */
> + if (tp->time_stamp[head] < ticks - tp->psp) {
> + tp->psample[head] = NCWV_UNDEF;
> + return tmp;
> + }
> +
> + /* search for the max pipeack */
> + if(tp->psample[head] > tmp)
> + tmp = tp->psample[head];
> +
> + head = prevbin(head);
> + if(head == tp->head)
> + return tmp;
> + }
> +
> + return tmp;
> +}
> +
> +/* Initialise NewCWV state */
> +void
> +tcp_newcwv_reset(struct tcpcb *tp)
> +{
> + tp->prev_snd_una = tp->snd_una;
> + tp->prev_snd_nxt = tp->snd_nxt;
> + tp->cwnd_valid_ts = ticks;
> + tp->loss_flight_size = 0;
> +
> + tp->head = 0;
> + tp->psample[0] = NCWV_UNDEF;
> + tp->pipeack = NCWV_UNDEF;
> +}
> +
> +/* NewCWV actions at loss detection */
> +void
> +tcp_newcwv_enter_recovery(struct tcpcb *tp)
> +{
> + u_int32_t pipe;
> +
> + if(tp->pipeack == NCWV_UNDEF)
> + return;
> +
> + tp->prior_retrans = tp->t_sndrexmitpack;
> +
> + /* Calculate the flight size */
> + u_int32_t awnd = (tp->snd_nxt - tp->snd_fack) + tp->sackhint.sack_bytes_rexmit;
> + tp->loss_flight_size = awnd;
> +
> + pipe = MAX(tp->pipeack,tp->loss_flight_size);
> + tp->snd_cwnd = MAX(pipe >> 1,1);
> +}
> +
> +/* NewCWV actions at the end of recovery */
> +void
> +tcp_newcwv_end_recovery(struct tcpcb *tp)
> +{
> + u_int32_t retrans,pipe;
> +
> + retrans = (tp->t_sndrexmitpack - tp->prior_retrans) * tp->t_maxseg;
> + pipe = MAX(tp->pipeack,tp->loss_flight_size) - retrans;
> +
> + /* Ensure that snd_ssthresh is non 0 */
> + tp->snd_ssthresh = MAX(pipe >> 1,1);
> + tp->snd_cwnd = tp->snd_ssthresh;
> +}
> +
> +void
> +tcp_newcwv_datalim_closedown(struct tcpcb *tp)
> +{
> + while ((ticks - tp->cwnd_valid_ts) > NCWV_FIVEMINS &&
> + tp->snd_cwnd > tp->init_cwnd) {
> +
> + tp->cwnd_valid_ts += NCWV_FIVEMINS;
> + tp->snd_ssthresh = MAX( (3 * tp->snd_cwnd ) >> 2,tp->snd_ssthresh);
> + tp->snd_cwnd = MAX(tp->snd_cwnd >> 1, tp->init_cwnd);
> + }
> +}
>
> Property changes on: sys/netinet/tcp_newcwv.c
> ___________________________________________________________________
> Added: svn:mime-type
> ## -0,0 +1 ##
> +text/plain
> \ No newline at end of property
> Added: svn:keywords
> ## -0,0 +1 ##
> +FreeBSD=%H
> \ No newline at end of property
> Added: svn:eol-style
> ## -0,0 +1 ##
> +native
> \ No newline at end of property
> Index: sys/netinet/tcp_newcwv.h
> ===================================================================
> --- sys/netinet/tcp_newcwv.h (revision 0)
> +++ sys/netinet/tcp_newcwv.h (working copy)
> @@ -0,0 +1,39 @@
> +/*
> + * Copyright (c) 2014 Tom Jones <jones at sdf.org>
> + * 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 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.
> + *
> + */
> +
> +#ifndef _NETINET_TCP_NEWCWV_H_
> +#define _NETINET_TCP_NEWCWV_H_
> +
> +#include <netinet/tcp_var.h>
> +
> +void tcp_newcwv_update_pipeack(struct tcpcb *);
> +void tcp_newcwv_reset(struct tcpcb *);
> +void tcp_newcwv_enter_recovery(struct tcpcb *);
> +void tcp_newcwv_end_recovery(struct tcpcb *);
> +void tcp_newcwv_datalim_closedown(struct tcpcb *);
> +
> +#endif /* _NETINET_TCP_NEWCWV_H_ */
>
> Property changes on: sys/netinet/tcp_newcwv.h
> ___________________________________________________________________
> Added: svn:keywords
> ## -0,0 +1 ##
> +FreeBSD=%H
> \ No newline at end of property
> Added: svn:eol-style
> ## -0,0 +1 ##
> +native
> \ No newline at end of property
> Added: svn:mime-type
> ## -0,0 +1 ##
> +text/plain
> \ No newline at end of property
> Index: sys/netinet/tcp_output.c
> ===================================================================
> --- sys/netinet/tcp_output.c (revision 268040)
> +++ sys/netinet/tcp_output.c (working copy)
> @@ -74,6 +74,7 @@ __FBSDID("$FreeBSD$");
> #include <netinet/tcp_timer.h>
> #include <netinet/tcp_var.h>
> #include <netinet/tcpip.h>
> +#include <netinet/tcp_newcwv.h>
> #ifdef TCPDEBUG
> #include <netinet/tcp_debug.h>
> #endif
> @@ -691,6 +692,10 @@ send:
> #endif
> hdrlen = sizeof (struct tcpiphdr);
>
> + /* Trigger the newcwv timer */
> + if(V_tcp_do_newcwv)
> + tcp_newcwv_datalim_closedown(tp);
> +
> /*
> * Compute options for segment.
> * We only have to care about SYN and established connection
> Index: sys/netinet/tcp_subr.c
> ===================================================================
> --- sys/netinet/tcp_subr.c (revision 268040)
> +++ sys/netinet/tcp_subr.c (working copy)
> @@ -800,6 +800,7 @@ tcp_newtcpcb(struct inpcb *inp)
> tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
> if (V_tcp_do_sack)
> tp->t_flags |= TF_SACK_PERMIT;
> +
> TAILQ_INIT(&tp->snd_holes);
> tp->t_inpcb = inp; /* XXX */
> /*
> Index: sys/netinet/tcp_var.h
> ===================================================================
> --- sys/netinet/tcp_var.h (revision 268040)
> +++ sys/netinet/tcp_var.h (working copy)
> @@ -172,6 +172,20 @@ struct tcpcb {
> int t_sndzerowin; /* zero-window updates sent */
> u_int t_badrxtwin; /* window for retransmit recovery */
> u_char snd_limited; /* segments limited transmitted */
> +/* NewCWV releated state */
> + u_int32_t pipeack;
> + u_int32_t psp; /* pipeack sampling period */
> +
> + u_int32_t head;
> + u_int32_t psample[4]; /* pipe ack samples */
> + u_int32_t time_stamp[4]; /* time stamp samples */
> + u_int32_t prev_snd_una; /* previous snd_una in this sampe */
> + u_int32_t prev_snd_nxt; /* previous snd_nxt in this sampe */
> +
> + u_int32_t loss_flight_size; /* flightsize at loss detection */
> + u_int32_t prior_retrans; /* Retransmission before going into FR */
> + u_int32_t cwnd_valid_ts; /*last time cwnd was found valid */
> + u_int32_t init_cwnd; /* The inital cwnd */
> /* SACK related state */
> int snd_numholes; /* number of holes seen by sender */
> TAILQ_HEAD(sackhole_head, sackhole) snd_holes;
> @@ -605,6 +619,7 @@ VNET_DECLARE(int, tcp_recvspace);
> VNET_DECLARE(int, path_mtu_discovery);
> VNET_DECLARE(int, tcp_do_rfc3465);
> VNET_DECLARE(int, tcp_abc_l_var);
> +VNET_DECLARE(int, tcp_do_newcwv);
> #define V_tcb VNET(tcb)
> #define V_tcbinfo VNET(tcbinfo)
> #define V_tcp_mssdflt VNET(tcp_mssdflt)
> @@ -617,6 +632,7 @@ VNET_DECLARE(int, tcp_abc_l_var);
> #define V_path_mtu_discovery VNET(path_mtu_discovery)
> #define V_tcp_do_rfc3465 VNET(tcp_do_rfc3465)
> #define V_tcp_abc_l_var VNET(tcp_abc_l_var)
> +#define V_tcp_do_newcwv VNET(tcp_do_newcwv)
>
> VNET_DECLARE(int, tcp_do_sack); /* SACK enabled/disabled */
> VNET_DECLARE(int, tcp_sc_rst_sock_fail); /* RST on sock alloc failure */
>
> _______________________________________________
> freebsd-net at freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-net
> To unsubscribe, send any mail to "freebsd-net-unsubscribe at freebsd.org"
More information about the freebsd-net
mailing list