d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

tcp: remove tcp_timer_suspend()

Browse Source 
It was a temporary code added together with RACK to fight against
TCP timer races.
This commit is contained in:
Gleb Smirnoff 2022-12-07 09:00:48 -08:00
parent e68b379244
commit 918fa4227d
5 changed files with 0 additions and 128 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
sys/netinet/tcp_stacks/bbr.c
View File

@ -9919,10 +9919,6 @@ bbr_stop_all_timers(struct tcpcb *tp)
bbr = (struct tcp_bbr *)tp->t_fb_ptr;
bbr->rc_in_persist = 1;
}
tcp_timer_suspend(tp, TT_PERSIST);
tcp_timer_suspend(tp, TT_REXMT);
tcp_timer_suspend(tp, TT_KEEP);
tcp_timer_suspend(tp, TT_DELACK);
}
static void

4
sys/netinet/tcp_stacks/rack.c
View File

@ -7100,10 +7100,6 @@ rack_stop_all_timers(struct tcpcb *tp)
rack = (struct tcp_rack *)tp->t_fb_ptr;
rack->rc_in_persist = 1;
}
tcp_timer_suspend(tp, TT_PERSIST);
tcp_timer_suspend(tp, TT_REXMT);
tcp_timer_suspend(tp, TT_KEEP);
tcp_timer_suspend(tp, TT_DELACK);
}
static void

108
sys/netinet/tcp_timer.c
View File

@ -976,114 +976,6 @@ tcp_timer_active(struct tcpcb *tp, uint32_t timer_type)
return callout_active(t_callout);
}
/*
* Stop the timer from running, and apply a flag
* against the timer_flags that will force the
* timer never to run. The flag is needed to assure
* a race does not leave it running and cause
* the timer to possibly restart itself (keep and persist
* especially do this).
*/
int
tcp_timer_suspend(struct tcpcb *tp, uint32_t timer_type)
{
struct callout *t_callout;
uint32_t t_flags;
switch (timer_type) {
case TT_DELACK:
t_flags = TT_DELACK_SUS;
t_callout = &tp->tt_delack;
break;
case TT_REXMT:
t_flags = TT_REXMT_SUS;
t_callout = &tp->tt_rexmt;
break;
case TT_PERSIST:
t_flags = TT_PERSIST_SUS;
t_callout = &tp->tt_persist;
break;
case TT_KEEP:
t_flags = TT_KEEP_SUS;
t_callout = &tp->tt_keep;
break;
case TT_2MSL:
t_flags = TT_2MSL_SUS;
t_callout = &tp->tt_2msl;
break;
default:
panic("tp:%p bad timer_type 0x%x", tp, timer_type);
}
tp->tt_flags |= t_flags;
return (callout_stop(t_callout));
}
void
tcp_timers_unsuspend(struct tcpcb *tp, uint32_t timer_type)
{
switch (timer_type) {
case TT_DELACK:
if (tp->tt_flags & TT_DELACK_SUS) {
tp->tt_flags &= ~TT_DELACK_SUS;
if (tp->t_flags & TF_DELACK) {
/* Delayed ack timer should be up activate a timer */
tp->t_flags &= ~TF_DELACK;
tcp_timer_activate(tp, TT_DELACK,
tcp_delacktime);
}
}
break;
case TT_REXMT:
if (tp->tt_flags & TT_REXMT_SUS) {
tp->tt_flags &= ~TT_REXMT_SUS;
if (SEQ_GT(tp->snd_max, tp->snd_una) &&
(tcp_timer_active((tp), TT_PERSIST) == 0) &&
tp->snd_wnd) {
/* We have outstanding data activate a timer */
tcp_timer_activate(tp, TT_REXMT,
tp->t_rxtcur);
}
}
break;
case TT_PERSIST:
if (tp->tt_flags & TT_PERSIST_SUS) {
tp->tt_flags &= ~TT_PERSIST_SUS;
if (tp->snd_wnd == 0) {
/* Activate the persists timer */
tp->t_rxtshift = 0;
tcp_setpersist(tp);
}
}
break;
case TT_KEEP:
if (tp->tt_flags & TT_KEEP_SUS) {
tp->tt_flags &= ~TT_KEEP_SUS;
tcp_timer_activate(tp, TT_KEEP,
TCPS_HAVEESTABLISHED(tp->t_state) ?
TP_KEEPIDLE(tp) : TP_KEEPINIT(tp));
}
break;
case TT_2MSL:
if (tp->tt_flags &= TT_2MSL_SUS) {
struct socket *so = tptosocket(tp);
tp->tt_flags &= ~TT_2MSL_SUS;
if ((tp->t_state == TCPS_FIN_WAIT_2) &&
(so == NULL || /* XXXGL: needed? */
(so->so_rcv.sb_state & SBS_CANTRCVMORE))) {
/* Star the 2MSL timer */
tcp_timer_activate(tp, TT_2MSL,
(tcp_fast_finwait2_recycle) ?
tcp_finwait2_timeout : TP_MAXIDLE(tp));
}
}
break;
default:
panic("tp:%p bad timer_type 0x%x", tp, timer_type);
}
}
static void
tcp_timer_discard(void *ptp)
{

10
sys/netinet/tcp_timer.h
View File

@ -155,16 +155,6 @@ static const char *tcptimers[] =
#define TT_2MSL 0x0010
#define TT_MASK (TT_DELACK|TT_REXMT|TT_PERSIST|TT_KEEP|TT_2MSL)
/*
* Suspend flags - used when suspending a timer
* from ever running again.
*/
#define TT_DELACK_SUS 0x0100
#define TT_REXMT_SUS 0x0200
#define TT_PERSIST_SUS 0x0400
#define TT_KEEP_SUS 0x0800
#define TT_2MSL_SUS 0x1000
#define TT_STOPPED 0x00010000
#define TP_KEEPINIT(tp) ((tp)->t_keepinit ? (tp)->t_keepinit : tcp_keepinit)

2
sys/netinet/tcp_var.h
View File

@ -1187,8 +1187,6 @@ struct tcptemp *
tcpip_maketemplate(struct inpcb *);
void tcpip_fillheaders(struct inpcb *, uint16_t, void *, void *);
void tcp_timer_activate(struct tcpcb *, uint32_t, u_int);
int tcp_timer_suspend(struct tcpcb *, uint32_t);
void tcp_timers_unsuspend(struct tcpcb *, uint32_t);
int tcp_timer_active(struct tcpcb *, uint32_t);
void tcp_timer_stop(struct tcpcb *, uint32_t);
void tcp_trace(short, short, struct tcpcb *, void *, struct tcphdr *, int);