net: rcu-ify tcf_proto
rcu'ify tcf_proto this allows calling tc_classify() without holding
any locks. Updaters are protected by RTNL.
This patch prepares the core net_sched infrastracture for running
the classifier/action chains without holding the qdisc lock however
it does nothing to ensure cls_xxx and act_xxx types also work without
locking. Additional patches are required to address the fall out.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 56838ab..1e89b9a 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -143,7 +143,7 @@
void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
/* Filter manipulation */
- struct tcf_proto ** (*tcf_chain)(struct Qdisc *, unsigned long);
+ struct tcf_proto __rcu ** (*tcf_chain)(struct Qdisc *, unsigned long);
unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
u32 classid);
void (*unbind_tcf)(struct Qdisc *, unsigned long);
@@ -212,8 +212,8 @@
struct tcf_proto {
/* Fast access part */
- struct tcf_proto *next;
- void *root;
+ struct tcf_proto __rcu *next;
+ void __rcu *root;
int (*classify)(struct sk_buff *,
const struct tcf_proto *,
struct tcf_result *);
@@ -225,6 +225,7 @@
struct Qdisc *q;
void *data;
const struct tcf_proto_ops *ops;
+ struct rcu_head rcu;
};
struct qdisc_skb_cb {
@@ -378,7 +379,7 @@
void __qdisc_calculate_pkt_len(struct sk_buff *skb,
const struct qdisc_size_table *stab);
void tcf_destroy(struct tcf_proto *tp);
-void tcf_destroy_chain(struct tcf_proto **fl);
+void tcf_destroy_chain(struct tcf_proto __rcu **fl);
/* Reset all TX qdiscs greater then index of a device. */
static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)