From dece40e848f6e022f960dc9de54be518928460c3 Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Wed, 13 Mar 2013 23:40:14 +0000 Subject: netfilter: nf_conntrack: speed up module removal path if netns in use The patch introduces nf_conntrack_cleanup_net_list(), which cleanups nf_conntrack for a list of netns and calls synchronize_net() only once for them all. This should reduce netns destruction time. I've measured cleanup time for 1k dummy net ns. Here are the results: # modprobe nf_conntrack # time modprobe -r nf_conntrack real 0m10.337s user 0m0.000s sys 0m0.376s # modprobe nf_conntrack # time modprobe -r nf_conntrack real 0m5.661s user 0m0.000s sys 0m0.216s Signed-off-by: Vladimir Davydov Cc: Patrick McHardy Cc: "David S. Miller" Cc: "Eric W. Biederman" Acked-by: Gao feng Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_core.c | 46 +++++++++++++++++++++++++++------------ 1 file changed, 32 insertions(+), 14 deletions(-) (limited to 'net/netfilter/nf_conntrack_core.c') diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 1068deb97c8b..007e8c43d19a 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1365,30 +1365,48 @@ void nf_conntrack_cleanup_end(void) */ void nf_conntrack_cleanup_net(struct net *net) { + LIST_HEAD(single); + + list_add(&net->exit_list, &single); + nf_conntrack_cleanup_net_list(&single); +} + +void nf_conntrack_cleanup_net_list(struct list_head *net_exit_list) +{ + int busy; + struct net *net; + /* * This makes sure all current packets have passed through * netfilter framework. Roll on, two-stage module * delete... */ synchronize_net(); - i_see_dead_people: - nf_ct_iterate_cleanup(net, kill_all, NULL); - nf_ct_release_dying_list(net); - if (atomic_read(&net->ct.count) != 0) { +i_see_dead_people: + busy = 0; + list_for_each_entry(net, net_exit_list, exit_list) { + nf_ct_iterate_cleanup(net, kill_all, NULL); + nf_ct_release_dying_list(net); + if (atomic_read(&net->ct.count) != 0) + busy = 1; + } + if (busy) { schedule(); goto i_see_dead_people; } - nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size); - nf_conntrack_proto_pernet_fini(net); - nf_conntrack_helper_pernet_fini(net); - nf_conntrack_ecache_pernet_fini(net); - nf_conntrack_tstamp_pernet_fini(net); - nf_conntrack_acct_pernet_fini(net); - nf_conntrack_expect_pernet_fini(net); - kmem_cache_destroy(net->ct.nf_conntrack_cachep); - kfree(net->ct.slabname); - free_percpu(net->ct.stat); + list_for_each_entry(net, net_exit_list, exit_list) { + nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size); + nf_conntrack_proto_pernet_fini(net); + nf_conntrack_helper_pernet_fini(net); + nf_conntrack_ecache_pernet_fini(net); + nf_conntrack_tstamp_pernet_fini(net); + nf_conntrack_acct_pernet_fini(net); + nf_conntrack_expect_pernet_fini(net); + kmem_cache_destroy(net->ct.nf_conntrack_cachep); + kfree(net->ct.slabname); + free_percpu(net->ct.stat); + } } void *nf_ct_alloc_hashtable(unsigned int *sizep, int nulls) -- cgit v1.2.3-55-g7522