From bb60a68985c8902f4061f1e3338a74e5f7d36a5d Mon Sep 17 00:00:00 2001 From: Richard Scheffenegger Date: Fri, 5 Mar 2021 17:45:23 +0100 Subject: [PATCH] tcp: remove incorrect reset of SACK variable in PRR tcp: Add prr_out in preparation for PRR/nonSACK and LRD Reviewed by: #transport, rrs, tuexen, kbowling Approved by: #re (gjb) PR: 253848 MFC after: 3 days Sponsored by: NetApp, Inc. Differential Revision: https://reviews.freebsd.org/D29083 Differential Revision: https://reviews.freebsd.org/D29058 (cherry picked from commit 4a8f3aad37dd35c905e34b64b022d60844ba8d01) (cherry picked from commit d90bba73a2e43fa12ea19425d101df4c488c1070) (cherry picked from commit e53138694aa41c24c17847afe959225ce0eeff91) (cherry picked from commit 71cc98ba735283b8720c9031eb87810f3d3d96a0) --- sys/netinet/tcp_input.c | 22 ++++++++-------------- sys/netinet/tcp_output.c | 8 ++++++++ sys/netinet/tcp_var.h | 2 +- 3 files changed, 17 insertions(+), 15 deletions(-) diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c index f2edbecbb07..3efc100bf89 100644 --- a/sys/netinet/tcp_input.c +++ b/sys/netinet/tcp_input.c @@ -510,6 +510,7 @@ cc_post_recovery(struct tcpcb *tp, struct tcphdr *th) } /* XXXLAS: EXIT_RECOVERY ? */ tp->t_bytes_acked = 0; + tp->sackhint.prr_out = 0; } /* @@ -2598,17 +2599,14 @@ tcp_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so, imax(1, tp->snd_nxt - tp->snd_una); snd_cnt = howmany((long)tp->sackhint.prr_delivered * tp->snd_ssthresh, tp->sackhint.recover_fs) - - (tp->sackhint.sack_bytes_rexmit + - (tp->snd_nxt - tp->snd_recover)); + tp->sackhint.prr_out; } else { if (V_tcp_do_prr_conservative) limit = tp->sackhint.prr_delivered - - (tp->sackhint.sack_bytes_rexmit + - (tp->snd_nxt - tp->snd_recover)); + tp->sackhint.prr_out; else limit = imax(tp->sackhint.prr_delivered - - (tp->sackhint.sack_bytes_rexmit + - (tp->snd_nxt - tp->snd_recover)), + tp->sackhint.prr_out, del_data) + maxseg; snd_cnt = imin(tp->snd_ssthresh - pipe, limit); } @@ -2682,7 +2680,6 @@ tcp_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so, */ tp->sackhint.prr_delivered = tp->sackhint.sacked_bytes; - tp->sackhint.sack_bytes_rexmit = 0; tp->sackhint.recover_fs = max(1, tp->snd_nxt - tp->snd_una); } @@ -3951,18 +3948,15 @@ tcp_prr_partialack(struct tcpcb *tp, struct tcphdr *th) imax(1, tp->snd_nxt - tp->snd_una); snd_cnt = howmany((long)tp->sackhint.prr_delivered * tp->snd_ssthresh, tp->sackhint.recover_fs) - - (tp->sackhint.sack_bytes_rexmit + - (tp->snd_nxt - tp->snd_recover)); + tp->sackhint.prr_out; } else { if (V_tcp_do_prr_conservative) limit = tp->sackhint.prr_delivered - - (tp->sackhint.sack_bytes_rexmit + - (tp->snd_nxt - tp->snd_recover)); + tp->sackhint.prr_out; else limit = imax(tp->sackhint.prr_delivered - - (tp->sackhint.sack_bytes_rexmit + - (tp->snd_nxt - tp->snd_recover)), - del_data) + maxseg; + tp->sackhint.prr_out, del_data) + + maxseg; snd_cnt = imin((tp->snd_ssthresh - pipe), limit); } snd_cnt = imax(snd_cnt, 0) / maxseg; diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c index b4c7ab0a1ab..d4b5a328e2a 100644 --- a/sys/netinet/tcp_output.c +++ b/sys/netinet/tcp_output.c @@ -1236,6 +1236,14 @@ tcp_output(struct tcpcb *tp) p->rxmit += len; tp->sackhint.sack_bytes_rexmit += len; } + if (IN_RECOVERY(tp->t_flags)) { + /* + * Account all bytes transmitted while + * IN_RECOVERY, simplifying PRR and + * Lost Retransmit Detection + */ + tp->sackhint.prr_out += len; + } th->th_ack = htonl(tp->rcv_nxt); if (optlen) { bcopy(opt, th + 1, optlen); diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h index 6e22d75ac44..3b007fcfcc9 100644 --- a/sys/netinet/tcp_var.h +++ b/sys/netinet/tcp_var.h @@ -115,7 +115,7 @@ struct sackhint { */ uint32_t recover_fs; /* Flight Size at the start of Loss recovery */ uint32_t prr_delivered; /* Total bytes delivered using PRR */ - uint32_t _pad[1]; /* TBD */ + uint32_t prr_out; /* Bytes sent during IN_RECOVERY */ }; #define SEGQ_EMPTY(tp) TAILQ_EMPTY(&(tp)->t_segq) -- 2.45.0