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Fix the VLAN_ARRAY case, mostly regarding improper use of atomic(9)

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in place of conventional rw locking.  Alas, atomic(9) can't buy us
lockless operation so easily.
This commit is contained in:
Yaroslav Tykhiy 2006-06-21 13:48:34 +00:00
parent 455dd7d4c7
commit 15ed2fa1f1
1 changed files with 16 additions and 30 deletions
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46
sys/net/if_vlan.c
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@ -912,19 +912,12 @@ vlan_input(struct ifnet *ifp, struct mbuf *m)
}
}
/*
* In VLAN_ARRAY case we proceed completely lockless.
*/
TRUNK_RLOCK(trunk);
#ifdef VLAN_ARRAY
ifv = trunk->vlans[tag];
if (ifv == NULL || (ifv->ifv_ifp->if_flags & IFF_UP) == 0) {
m_freem(m);
ifp->if_noproto++;
return;
}
#else
TRUNK_RLOCK(trunk);
ifv = vlan_gethash(trunk, tag);
#endif
if (ifv == NULL || (ifv->ifv_ifp->if_flags & IFF_UP) == 0) {
TRUNK_RUNLOCK(trunk);
m_freem(m);
@ -932,7 +925,6 @@ vlan_input(struct ifnet *ifp, struct mbuf *m)
return;
}
TRUNK_RUNLOCK(trunk);
#endif
if (mtag == NULL) {
/*
@ -997,16 +989,19 @@ exists:
TRUNK_LOCK(trunk);
}
ifv->ifv_tag = tag;
ifv->ifv_tag = tag; /* must set this before vlan_inshash() */
#ifdef VLAN_ARRAY
if (trunk->vlans[tag] != NULL)
if (trunk->vlans[tag] != NULL) {
error = EEXIST;
goto done;
}
trunk->vlans[tag] = ifv;
trunk->refcnt++;
#else
error = vlan_inshash(trunk, ifv);
#endif
if (error)
goto done;
#endif
ifv->ifv_encaplen = ETHER_VLAN_ENCAP_LEN;
ifv->ifv_mintu = ETHERMIN;
ifv->ifv_pflags = 0;
@ -1061,11 +1056,6 @@ exists:
* joined on the vlan device.
*/
(void)vlan_setmulti(ifp); /* XXX: VLAN lock held */
#ifdef VLAN_ARRAY
atomic_store_rel_ptr((uintptr_t *)&trunk->vlans[tag], (uintptr_t)ifv);
trunk->refcnt++;
#endif
done:
TRUNK_UNLOCK(trunk);
VLAN_UNLOCK();
@ -1102,11 +1092,6 @@ vlan_unconfig_locked(struct ifnet *ifp)
struct ifnet *p = trunk->parent;
TRUNK_LOCK(trunk);
#ifdef VLAN_ARRAY
atomic_store_rel_ptr((uintptr_t *)&trunk->vlans[ifv->ifv_tag],
(uintptr_t)NULL);
trunk->refcnt--;
#endif
/*
* Since the interface is being unconfigured, we need to
@ -1132,7 +1117,10 @@ vlan_unconfig_locked(struct ifnet *ifp)
}
vlan_setflags(ifp, 0); /* clear special flags on parent */
#ifndef VLAN_ARRAY
#ifdef VLAN_ARRAY
trunk->vlans[ifv->ifv_tag] = NULL;
trunk->refcnt--;
#else
vlan_remhash(trunk, ifv);
#endif
ifv->ifv_trunk = NULL;
@ -1141,9 +1129,7 @@ vlan_unconfig_locked(struct ifnet *ifp)
* Check if we were the last.
*/
if (trunk->refcnt == 0) {
atomic_store_rel_ptr((uintptr_t *)
&trunk->parent->if_vlantrunk,
(uintptr_t)NULL);
trunk->parent->if_vlantrunk = NULL;
/*
* XXXGL: If some ithread has already entered
* vlan_input() and is now blocked on the trunk
@ -1233,7 +1219,7 @@ vlan_link_state(struct ifnet *ifp, int link)
TRUNK_LOCK(trunk);
#ifdef VLAN_ARRAY
for (i = 0; i < EVL_VLID_MASK+1; i++)
for (i = 0; i < VLAN_ARRAY_SIZE; i++)
if (trunk->vlans[i] != NULL) {
ifv = trunk->vlans[i];
#else
@ -1282,7 +1268,7 @@ vlan_trunk_capabilities(struct ifnet *ifp)
TRUNK_LOCK(trunk);
#ifdef VLAN_ARRAY
for (i = 0; i < EVL_VLID_MASK+1; i++)
for (i = 0; i < VLAN_ARRAY_SIZE; i++)
if (trunk->vlans[i] != NULL) {
ifv = trunk->vlans[i];
#else