[PATCH net-next 09/13] net: sched: extend tcf_block with rcu

[Vlad Buslov]

Extend tcf_block with rcu to allow safe deallocation when it is accessed
concurrently.

Signed-off-by: Vlad Buslov <vla...@mellanox.com>
Acked-by: Jiri Pirko <j...@mellanox.com>
---
 include/net/sch_generic.h | 1 +
 net/sched/cls_api.c       | 6 +++---
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 825e2bf6c5c3..2b87b47c49f6 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -357,6 +357,7 @@ struct tcf_block {
                struct tcf_chain *chain;
                struct list_head filter_chain_list;
        } chain0;
+       struct rcu_head rcu;
 };
 
 static inline void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index f11da74dd339..502b2da8a885 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -241,7 +241,7 @@ static void tcf_chain_destroy(struct tcf_chain *chain)
                block->chain0.chain = NULL;
        kfree(chain);
        if (list_empty(&block->chain_list) && !refcount_read(&block->refcnt))
-               kfree(block);
+               kfree_rcu(block, rcu);
 }
 
 static void tcf_chain_hold(struct tcf_chain *chain)
@@ -785,7 +785,7 @@ int tcf_block_attach_ext(struct tcf_block **p_block, struct 
Qdisc *q,
                if (tcf_block_shared(block))
                        tcf_block_remove(block, net);
 err_block_insert:
-               kfree(block);
+               kfree_rcu(block, rcu);
        } else {
                refcount_dec(&block->refcnt);
        }
@@ -841,7 +841,7 @@ void tcf_block_detach_ext(struct tcf_block *block, struct 
Qdisc *q,
                tcf_block_offload_unbind(block, q, ei);
 
                if (free_block)
-                       kfree(block);
+                       kfree_rcu(block, rcu);
                else
                        tcf_block_put_all_chains(block);
        } else {
-- 
2.7.5