diff options
Diffstat (limited to 'sys/netinet/tcp_syncache.c')
| -rw-r--r-- | sys/netinet/tcp_syncache.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/sys/netinet/tcp_syncache.c b/sys/netinet/tcp_syncache.c index 7d97ae081a6b..2c853b3b55e2 100644 --- a/sys/netinet/tcp_syncache.c +++ b/sys/netinet/tcp_syncache.c @@ -652,6 +652,8 @@ done: /* * Build a new TCP socket structure from a syncache entry. + * + * On success return the newly created socket with its underlying inp locked. */ static struct socket * syncache_socket(struct syncache *sc, struct socket *lso, struct mbuf *m) @@ -662,7 +664,7 @@ syncache_socket(struct syncache *sc, struct socket *lso, struct mbuf *m) int error; char *s; - INP_INFO_WLOCK_ASSERT(&V_tcbinfo); + INP_INFO_RLOCK_ASSERT(&V_tcbinfo); /* * Ok, create the full blown connection, and set things up @@ -693,6 +695,15 @@ syncache_socket(struct syncache *sc, struct socket *lso, struct mbuf *m) inp = sotoinpcb(so); inp->inp_inc.inc_fibnum = so->so_fibnum; INP_WLOCK(inp); + /* + * Exclusive pcbinfo lock is not required in syncache socket case even + * if two inpcb locks can be acquired simultaneously: + * - the inpcb in LISTEN state, + * - the newly created inp. + * + * In this case, an inp cannot be at same time in LISTEN state and + * just created by an accept() call. + */ INP_HASH_WLOCK(&V_tcbinfo); /* Insert new socket into PCB hash list. */ @@ -907,8 +918,6 @@ syncache_socket(struct syncache *sc, struct socket *lso, struct mbuf *m) tp->t_keepcnt = sototcpcb(lso)->t_keepcnt; tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp)); - INP_WUNLOCK(inp); - soisconnected(so); TCPSTAT_INC(tcps_accepts); @@ -928,6 +937,9 @@ abort2: * in the syncache, and if its there, we pull it out of * the cache and turn it into a full-blown connection in * the SYN-RECEIVED state. + * + * On syncache_socket() success the newly created socket + * has its underlying inp locked. */ int syncache_expand(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th, @@ -942,7 +954,7 @@ syncache_expand(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th, * Global TCP locks are held because we manipulate the PCB lists * and create a new socket. */ - INP_INFO_WLOCK_ASSERT(&V_tcbinfo); + INP_INFO_RLOCK_ASSERT(&V_tcbinfo); KASSERT((th->th_flags & (TH_RST|TH_ACK|TH_SYN)) == TH_ACK, ("%s: can handle only ACK", __func__)); |