diff options
author | ps <ps@FreeBSD.org> | 2005-05-16 19:26:46 +0000 |
---|---|---|
committer | ps <ps@FreeBSD.org> | 2005-05-16 19:26:46 +0000 |
commit | 8ce92141654e5d67cc364bb2ee7a489a706eec6e (patch) | |
tree | e8340c78f542cd4fade7607a898e9e7f8b8182f8 | |
parent | 9c27dea05c97bcaaac607040af189fc38bc4020f (diff) | |
download | FreeBSD-src-8ce92141654e5d67cc364bb2ee7a489a706eec6e.zip FreeBSD-src-8ce92141654e5d67cc364bb2ee7a489a706eec6e.tar.gz |
Introduce routines to alloc/free sack holes. This cleans up the code
considerably.
Submitted by: Noritoshi Demizu.
Reviewed by: Raja Mukerji, Mohan Srinivasan.
-rw-r--r-- | sys/netinet/tcp_sack.c | 116 |
1 files changed, 60 insertions, 56 deletions
diff --git a/sys/netinet/tcp_sack.c b/sys/netinet/tcp_sack.c index aec8400..847d8f7 100644 --- a/sys/netinet/tcp_sack.c +++ b/sys/netinet/tcp_sack.c @@ -286,6 +286,49 @@ tcp_clean_sackreport(tp) } /* + * Allocate struct sackhole. + */ +static struct sackhole * +tcp_sackhole_alloc(struct tcpcb *tp, tcp_seq start, tcp_seq end) +{ + struct sackhole *hole; + + if (tp->snd_numholes >= tcp_sack_maxholes || + tcp_sack_globalholes >= tcp_sack_globalmaxholes) { + tcpstat.tcps_sack_sboverflow++; + return NULL; + } + + hole = (struct sackhole *)uma_zalloc(sack_hole_zone, M_NOWAIT); + if (hole == NULL) + return NULL; + + hole->start = start; + hole->end = end; + hole->rxmit = start; + + tp->snd_numholes++; + tcp_sack_globalholes++; + + return hole; +} + +/* + * Free struct sackhole. + */ +static void +tcp_sackhole_free(struct tcpcb *tp, struct sackhole *hole) +{ + uma_zfree(sack_hole_zone, hole); + + tp->snd_numholes--; + tcp_sack_globalholes--; + + KASSERT(tp->snd_numholes >= 0, ("tp->snd_numholes >= 0")); + KASSERT(tcp_sack_globalholes >= 0, ("tcp_sack_globalholes >= 0")); +} + +/* * Process the TCP SACK option. Returns 1 if tcp_dooptions() should continue, * and 0 otherwise, if the option was fine. tp->snd_holes is an ordered list * of holes (oldest to newest, in terms of the sequence space). @@ -311,8 +354,6 @@ tcp_sack_option(struct tcpcb *tp, struct tcphdr *th, u_char *cp, int optlen) tmp_cp = cp + 2; tmp_olen = optlen - 2; tcpstat.tcps_sack_rcv_blocks++; - if (tp->snd_numholes < 0) /* XXX panic? */ - tp->snd_numholes = 0; if (tp->t_maxseg == 0) panic("tcp_sack_option"); /* Should never happen */ while (tmp_olen > 0) { @@ -336,26 +377,15 @@ tcp_sack_option(struct tcpcb *tp, struct tcphdr *th, u_char *cp, int optlen) if (SEQ_GT(sack.end, tp->snd_max)) continue; if (TAILQ_EMPTY(&tp->snd_holes)) { /* first hole */ - if (tcp_sack_globalholes >= tcp_sack_globalmaxholes || - tcp_sack_maxholes == 0) { - tcpstat.tcps_sack_sboverflow++; - continue; - } - cur = (struct sackhole *) - uma_zalloc(sack_hole_zone,M_NOWAIT); + cur = tcp_sackhole_alloc(tp, th->th_ack, sack.start); if (cur == NULL) { /* ENOBUFS, so ignore SACKed block for now*/ continue; } - cur->start = th->th_ack; - cur->end = sack.start; - cur->rxmit = cur->start; - tp->snd_numholes = 1; - tcp_sack_globalholes++; + TAILQ_INSERT_HEAD(&tp->snd_holes, cur, scblink); + tp->rcv_lastsack = sack.end; /* Update the sack scoreboard "cache" */ tp->sackhint.nexthole = cur; - tp->rcv_lastsack = sack.end; - TAILQ_INSERT_HEAD(&tp->snd_holes, cur, scblink); continue; /* with next sack block */ } /* Go thru list of holes. */ @@ -384,9 +414,7 @@ tcp_sack_option(struct tcpcb *tp, struct tcphdr *th, u_char *cp, int optlen) cur = TAILQ_NEXT(cur, scblink); TAILQ_REMOVE(&tp->snd_holes, temp, scblink); - uma_zfree(sack_hole_zone, temp); - tp->snd_numholes--; - tcp_sack_globalholes--; + tcp_sackhole_free(tp, temp); continue; } else { /* Move start of hole forward */ @@ -402,31 +430,19 @@ tcp_sack_option(struct tcpcb *tp, struct tcphdr *th, u_char *cp, int optlen) * ACKs some data in middle of a hole; need to * split current hole */ - if (tp->snd_numholes >= tcp_sack_maxholes || - tcp_sack_globalholes >= - tcp_sack_globalmaxholes) { - tcpstat.tcps_sack_sboverflow++; - temp = NULL; - } else { - temp = (struct sackhole *) - uma_zalloc(sack_hole_zone, - M_NOWAIT); - } + temp = tcp_sackhole_alloc(tp, sack.end, + cur->end); if (temp != NULL) { - temp->start = sack.end; - temp->end = cur->end; - temp->rxmit = SEQ_MAX(cur->rxmit, - temp->start); + if (SEQ_GT(cur->rxmit, temp->rxmit)) + temp->rxmit = cur->rxmit; + TAILQ_INSERT_AFTER(&tp->snd_holes, + cur, temp, scblink); cur->end = sack.start; cur->rxmit = SEQ_MIN(cur->rxmit, cur->end); tp->sackhint.sack_bytes_rexmit += (cur->rxmit - cur->start); - TAILQ_INSERT_AFTER(&tp->snd_holes, - cur, temp, scblink); cur = temp; - tp->snd_numholes++; - tcp_sack_globalholes++; } } tp->sackhint.sack_bytes_rexmit += @@ -436,22 +452,12 @@ tcp_sack_option(struct tcpcb *tp, struct tcphdr *th, u_char *cp, int optlen) /* At this point, we have iterated the whole scoreboard. */ if (SEQ_LT(tp->rcv_lastsack, sack.start)) { /* Need to append new hole at end. */ - if (tp->snd_numholes >= tcp_sack_maxholes || - tcp_sack_globalholes >= tcp_sack_globalmaxholes) { - tcpstat.tcps_sack_sboverflow++; - continue; - } - temp = (struct sackhole *) - uma_zalloc(sack_hole_zone,M_NOWAIT); + temp = tcp_sackhole_alloc(tp, tp->rcv_lastsack, + sack.start); if (temp == NULL) continue; /* ENOBUFS */ - temp->start = tp->rcv_lastsack; - temp->end = sack.start; - temp->rxmit = temp->start; - tp->rcv_lastsack = sack.end; - tp->snd_numholes++; - tcp_sack_globalholes++; TAILQ_INSERT_TAIL(&tp->snd_holes, temp, scblink); + tp->rcv_lastsack = sack.end; if (tp->sackhint.nexthole == NULL) tp->sackhint.nexthole = temp; } @@ -488,9 +494,7 @@ tcp_del_sackholes(tp, th) TAILQ_NEXT(cur, scblink); cur = TAILQ_NEXT(cur, scblink); TAILQ_REMOVE(&tp->snd_holes, prev, scblink); - uma_zfree(sack_hole_zone, prev); - tp->snd_numholes--; - tcp_sack_globalholes--; + tcp_sackhole_free(tp, prev); } else if (SEQ_LT(cur->start, lastack)) { if (SEQ_LT(cur->rxmit, lastack)) { tp->sackhint.sack_bytes_rexmit -= @@ -514,12 +518,12 @@ tcp_free_sackholes(struct tcpcb *tp) INP_LOCK_ASSERT(tp->t_inpcb); while ((q = TAILQ_FIRST(&tp->snd_holes)) != NULL) { TAILQ_REMOVE(&tp->snd_holes, q, scblink); - uma_zfree(sack_hole_zone, q); - tcp_sack_globalholes--; + tcp_sackhole_free(tp, q); } - tp->snd_numholes = 0; tp->sackhint.nexthole = NULL; tp->sackhint.sack_bytes_rexmit = 0; + + KASSERT(tp->snd_numholes == 0, ("tp->snd_numholes == 0")); } /* |