From ed7aa879ce1a0ff6468c5a6d3eb4e31169b95c4a Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Tue, 25 Aug 2015 20:06:33 -0700 Subject: [PATCH] net_sched: convert tcindex to call tcf_exts_destroy from rcu callback Adjust destroy path of cls_tcindex to call tcf_exts_destroy() after rcu grace period. Signed-off-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- net/sched/cls_tcindex.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-) diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c index a557dbaf5afe..944c8ff45055 100644 --- a/net/sched/cls_tcindex.c +++ b/net/sched/cls_tcindex.c @@ -27,6 +27,7 @@ struct tcindex_filter_result { struct tcf_exts exts; struct tcf_result res; + struct rcu_head rcu; }; struct tcindex_filter { @@ -133,8 +134,23 @@ static int tcindex_init(struct tcf_proto *tp) return 0; } -static int -tcindex_delete(struct tcf_proto *tp, unsigned long arg) +static void tcindex_destroy_rexts(struct rcu_head *head) +{ + struct tcindex_filter_result *r; + + r = container_of(head, struct tcindex_filter_result, rcu); + tcf_exts_destroy(&r->exts); +} + +static void tcindex_destroy_fexts(struct rcu_head *head) +{ + struct tcindex_filter *f = container_of(head, struct tcindex_filter, rcu); + + tcf_exts_destroy(&f->result.exts); + kfree(f); +} + +static int tcindex_delete(struct tcf_proto *tp, unsigned long arg) { struct tcindex_data *p = rtnl_dereference(tp->root); struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg; @@ -162,9 +178,14 @@ found: rcu_assign_pointer(*walk, rtnl_dereference(f->next)); } tcf_unbind_filter(tp, &r->res); - tcf_exts_destroy(&r->exts); + /* all classifiers are required to call tcf_exts_destroy() after rcu + * grace period, since converted-to-rcu actions are relying on that + * in cleanup() callback + */ if (f) - kfree_rcu(f, rcu); + call_rcu(&f->rcu, tcindex_destroy_fexts); + else + call_rcu(&r->rcu, tcindex_destroy_rexts); return 0; } -- 2.30.2