From 25d8c0d55f241ce2d360df1bea48e23a55836ee6 Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Fri, 12 Sep 2014 20:05:27 -0700 Subject: 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 Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/sched/sch_drr.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'net/sched/sch_drr.c') diff --git a/net/sched/sch_drr.c b/net/sched/sch_drr.c index 7bbbfe112192..d8b5ccfd248a 100644 --- a/net/sched/sch_drr.c +++ b/net/sched/sch_drr.c @@ -35,7 +35,7 @@ struct drr_class { struct drr_sched { struct list_head active; - struct tcf_proto *filter_list; + struct tcf_proto __rcu *filter_list; struct Qdisc_class_hash clhash; }; @@ -184,7 +184,8 @@ static void drr_put_class(struct Qdisc *sch, unsigned long arg) drr_destroy_class(sch, cl); } -static struct tcf_proto **drr_tcf_chain(struct Qdisc *sch, unsigned long cl) +static struct tcf_proto __rcu **drr_tcf_chain(struct Qdisc *sch, + unsigned long cl) { struct drr_sched *q = qdisc_priv(sch); @@ -319,6 +320,7 @@ static struct drr_class *drr_classify(struct sk_buff *skb, struct Qdisc *sch, struct drr_sched *q = qdisc_priv(sch); struct drr_class *cl; struct tcf_result res; + struct tcf_proto *fl; int result; if (TC_H_MAJ(skb->priority ^ sch->handle) == 0) { @@ -328,7 +330,8 @@ static struct drr_class *drr_classify(struct sk_buff *skb, struct Qdisc *sch, } *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; - result = tc_classify(skb, q->filter_list, &res); + fl = rcu_dereference_bh(q->filter_list); + result = tc_classify(skb, fl, &res); if (result >= 0) { #ifdef CONFIG_NET_CLS_ACT switch (result) { -- cgit v1.2.3