diff options
| author | Julian Anastasov <ja@ssi.bg> | 2013-10-09 09:24:27 +0300 |
|---|---|---|
| committer | Simon Horman <horms@verge.net.au> | 2013-10-15 10:36:01 +0900 |
| commit | 9e4e948a3edafd2b7f4dc14c395e146ffd0d9611 (patch) | |
| tree | 2432d5bc712bc0ed0ab9f978807190d093bcd1d3 /net/netfilter | |
| parent | 120c9794a3ee2f9b1548a1b0b252652e3c134f59 (diff) | |
ipvs: avoid rcu_barrier during netns cleanup
commit 578bc3ef1e473a ("ipvs: reorganize dest trash") added
rcu_barrier() on cleanup to wait dest users and schedulers
like LBLC and LBLCR to put their last dest reference.
Using rcu_barrier with many namespaces is problematic.
Trying to fix it by freeing dest with kfree_rcu is not
a solution, RCU callbacks can run in parallel and execution
order is random.
Fix it by creating new function ip_vs_dest_put_and_free()
which is heavier than ip_vs_dest_put(). We will use it just
for schedulers like LBLC, LBLCR that can delay their dest
release.
By default, dests reference is above 0 if they are present in
service and it is 0 when deleted but still in trash list.
Change the dest trash code to use ip_vs_dest_put_and_free(),
so that refcnt -1 can be used for freeing. As result,
such checks remain in slow path and the rcu_barrier() from
netns cleanup can be removed.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/ipvs/ip_vs_ctl.c | 6 | ||||
| -rw-r--r-- | net/netfilter/ipvs/ip_vs_lblc.c | 2 | ||||
| -rw-r--r-- | net/netfilter/ipvs/ip_vs_lblcr.c | 2 |
3 files changed, 3 insertions, 7 deletions
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index a3df9bddc4f..62786a495ce 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -704,7 +704,7 @@ static void ip_vs_dest_free(struct ip_vs_dest *dest) __ip_vs_dst_cache_reset(dest); __ip_vs_svc_put(svc, false); free_percpu(dest->stats.cpustats); - kfree(dest); + ip_vs_dest_put_and_free(dest); } /* @@ -3820,10 +3820,6 @@ void __net_exit ip_vs_control_net_cleanup(struct net *net) { struct netns_ipvs *ipvs = net_ipvs(net); - /* Some dest can be in grace period even before cleanup, we have to - * defer ip_vs_trash_cleanup until ip_vs_dest_wait_readers is called. - */ - rcu_barrier(); ip_vs_trash_cleanup(net); ip_vs_stop_estimator(net, &ipvs->tot_stats); ip_vs_control_net_cleanup_sysctl(net); diff --git a/net/netfilter/ipvs/ip_vs_lblc.c b/net/netfilter/ipvs/ip_vs_lblc.c index eff13c94498..ca056a331e6 100644 --- a/net/netfilter/ipvs/ip_vs_lblc.c +++ b/net/netfilter/ipvs/ip_vs_lblc.c @@ -136,7 +136,7 @@ static void ip_vs_lblc_rcu_free(struct rcu_head *head) struct ip_vs_lblc_entry, rcu_head); - ip_vs_dest_put(en->dest); + ip_vs_dest_put_and_free(en->dest); kfree(en); } diff --git a/net/netfilter/ipvs/ip_vs_lblcr.c b/net/netfilter/ipvs/ip_vs_lblcr.c index 0b8550089a2..3f21a2f47de 100644 --- a/net/netfilter/ipvs/ip_vs_lblcr.c +++ b/net/netfilter/ipvs/ip_vs_lblcr.c @@ -130,7 +130,7 @@ static void ip_vs_lblcr_elem_rcu_free(struct rcu_head *head) struct ip_vs_dest_set_elem *e; e = container_of(head, struct ip_vs_dest_set_elem, rcu_head); - ip_vs_dest_put(e->dest); + ip_vs_dest_put_and_free(e->dest); kfree(e); } |