neigh: support smaller retrans_time settting

Currently, we limited the retrans_time to be greater than HZ/2. i.e.
setting retrans_time less than 500ms will not work. This makes the user
unable to achieve a more accurate control for bonding arp fast failover.

Update the sanity check to HZ/100, which is 10ms, to let users have more
ability on the retrans_time control.

v3: sync the behavior with IPv6 and update all the timer handler
v2: use HZ instead of hard code number

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Hangbin Liu 2020-04-01 14:46:20 +08:00 committed by David S. Miller
parent 64948427a6
commit 19e16d220f
3 changed files with 12 additions and 9 deletions

View File

@ -1065,11 +1065,12 @@ static void neigh_timer_handler(struct timer_list *t)
neigh->updated = jiffies;
atomic_set(&neigh->probes, 0);
notify = 1;
next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
HZ/100);
}
} else {
/* NUD_PROBE|NUD_INCOMPLETE */
next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100);
}
if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
@ -1125,7 +1126,7 @@ int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
neigh->nud_state = NUD_INCOMPLETE;
neigh->updated = now;
next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
HZ/2);
HZ/100);
neigh_add_timer(neigh, next);
immediate_probe = true;
} else {
@ -1427,7 +1428,8 @@ void __neigh_set_probe_once(struct neighbour *neigh)
neigh->nud_state = NUD_INCOMPLETE;
atomic_set(&neigh->probes, neigh_max_probes(neigh));
neigh_add_timer(neigh,
jiffies + NEIGH_VAR(neigh->parms, RETRANS_TIME));
jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
HZ/100));
}
EXPORT_SYMBOL(__neigh_set_probe_once);

View File

@ -1357,7 +1357,7 @@ retry:
regen_advance = idev->cnf.regen_max_retry *
idev->cnf.dad_transmits *
NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
/* recalculate max_desync_factor each time and update
* idev->desync_factor if it's larger
@ -4121,7 +4121,8 @@ static void addrconf_dad_work(struct work_struct *w)
ifp->dad_probes--;
addrconf_mod_dad_work(ifp,
NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
HZ/100));
spin_unlock(&ifp->lock);
write_unlock_bh(&idev->lock);
@ -4527,7 +4528,7 @@ restart:
!(ifp->flags&IFA_F_TENTATIVE)) {
unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
ifp->idev->cnf.dad_transmits *
NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
if (age >= ifp->prefered_lft - regen_advance) {
struct inet6_ifaddr *ifpub = ifp->ifpub;

View File

@ -1359,8 +1359,8 @@ skip_defrtr:
if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
rtime = (rtime*HZ)/1000;
if (rtime < HZ/10)
rtime = HZ/10;
if (rtime < HZ/100)
rtime = HZ/100;
NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime);
in6_dev->tstamp = jiffies;
send_ifinfo_notify = true;