[net 1/1] tipc: set link tolerance correctly in broadcast link

[net 1/1] tipc: set link tolerance correctly in broadcast link

[Jon Maloy]

In the patch referred to below we added link tolerance as an additional
criteria for declaring broadcast transmission "stale" and resetting the
affected links.

However, the 'tolerance' field of the broadcast link is never set, and
remains at zero. This renders the whole commit without the intended
improving effect, but luckily also with no negative effect.

In this commit we add the missing initialization.

Fixes: a4dc70d46cf1 ("tipc: extend link reset criteria for stale packet
retransmission")

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/link.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/net/tipc/link.c b/net/tipc/link.c
index fb886b5..d229a36 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -477,6 +477,8 @@ bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
 	l->in_session = false;
 	l->bearer_id = bearer_id;
 	l->tolerance = tolerance;
+	if (bc_rcvlink)
+		bc_rcvlink->tolerance = tolerance;
 	l->net_plane = net_plane;
 	l->advertised_mtu = mtu;
 	l->mtu = mtu;
@@ -1031,7 +1033,7 @@ static int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r,
 	/* Detect repeated retransmit failures on same packet */
 	if (r->last_retransm != buf_seqno(skb)) {
 		r->last_retransm = buf_seqno(skb);
-		r->stale_limit = jiffies + msecs_to_jiffies(l->tolerance);
+		r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance);
 	} else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) {
 		link_retransmit_failure(l, skb);
 		if (link_is_bc_sndlink(l))
@@ -1576,9 +1578,10 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 		strncpy(if_name, data, TIPC_MAX_IF_NAME);
 
 		/* Update own tolerance if peer indicates a non-zero value */
-		if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
+		if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
 			l->tolerance = peers_tol;
-
+			l->bc_rcvlink->tolerance = peers_tol;
+		}
 		/* Update own priority if peer's priority is higher */
 		if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
 			l->priority = peers_prio;
@@ -1604,9 +1607,10 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 		l->rcv_nxt_state = msg_seqno(hdr) + 1;
 
 		/* Update own tolerance if peer indicates a non-zero value */
-		if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
+		if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
 			l->tolerance = peers_tol;
-
+			l->bc_rcvlink->tolerance = peers_tol;
+		}
 		/* Update own prio if peer indicates a different value */
 		if ((peers_prio != l->priority) &&
 		    in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
@@ -2223,6 +2227,8 @@ void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
 			     struct sk_buff_head *xmitq)
 {
 	l->tolerance = tol;
+	if (l->bc_rcvlink)
+		l->bc_rcvlink->tolerance = tol;
 	if (link_is_up(l))
 		tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
 }
-- 
2.1.4

Re: [net 1/1] tipc: set link tolerance correctly in broadcast link

[David Miller]

From: Jon Maloy <jon.maloy@ericsson.com>
Date: Wed, 10 Oct 2018 17:34:01 +0200

> In the patch referred to below we added link tolerance as an additional
> criteria for declaring broadcast transmission "stale" and resetting the
> affected links.
> 
> However, the 'tolerance' field of the broadcast link is never set, and
> remains at zero. This renders the whole commit without the intended
> improving effect, but luckily also with no negative effect.
> 
> In this commit we add the missing initialization.
> 
> Fixes: a4dc70d46cf1 ("tipc: extend link reset criteria for stale packet
> retransmission")
> 
> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>

Applied.