[patch net-next v2 20/20] net: sched: avoid atomic swap in tcf_exts_change

[Jiri Pirko]

From: Jiri Pirko <j...@mellanox.com>

tcf_exts_change is always called on newly created exts, which are not used
on fastpath. Therefore, simple struct copy is enough.

Signed-off-by: Jiri Pirko <j...@mellanox.com>
---
 include/net/pkt_cls.h   |  3 +--
 net/sched/cls_api.c     | 10 ++--------
 net/sched/cls_rsvp.h    |  4 ++--
 net/sched/cls_tcindex.c |  6 +++---
 4 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index b8959c9..e0c54f1 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -201,8 +201,7 @@ int tcf_exts_validate(struct net *net, struct tcf_proto *tp,
                      struct nlattr **tb, struct nlattr *rate_tlv,
                      struct tcf_exts *exts, bool ovr);
 void tcf_exts_destroy(struct tcf_exts *exts);
-void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
-                    struct tcf_exts *src);
+void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src);
 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts);
 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts);
 int tcf_exts_get_dev(struct net_device *dev, struct tcf_exts *exts,
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 735d556..e655221 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -883,18 +883,12 @@ int tcf_exts_validate(struct net *net, struct tcf_proto 
*tp, struct nlattr **tb,
 }
 EXPORT_SYMBOL(tcf_exts_validate);
 
-void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
-                    struct tcf_exts *src)
+void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
 {
 #ifdef CONFIG_NET_CLS_ACT
        struct tcf_exts old = *dst;
 
-       tcf_tree_lock(tp);
-       dst->nr_actions = src->nr_actions;
-       dst->actions = src->actions;
-       dst->type = src->type;
-       tcf_tree_unlock(tp);
-
+       *dst = *src;
        tcf_exts_destroy(&old);
 #endif
 }
diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
index 0d9d077..4adb67a 100644
--- a/net/sched/cls_rsvp.h
+++ b/net/sched/cls_rsvp.h
@@ -518,7 +518,7 @@ static int rsvp_change(struct net *net, struct sk_buff 
*in_skb,
                        tcf_bind_filter(tp, &n->res, base);
                }
 
-               tcf_exts_change(tp, &n->exts, &e);
+               tcf_exts_change(&n->exts, &e);
                rsvp_replace(tp, n, handle);
                return 0;
        }
@@ -591,7 +591,7 @@ static int rsvp_change(struct net *net, struct sk_buff 
*in_skb,
                        if (f->tunnelhdr == 0)
                                tcf_bind_filter(tp, &f->res, base);
 
-                       tcf_exts_change(tp, &f->exts, &e);
+                       tcf_exts_change(&f->exts, &e);
 
                        fp = &s->ht[h2];
                        for (nfp = rtnl_dereference(*fp); nfp;
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index 66924d1..d69f828 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -419,9 +419,9 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, 
unsigned long base,
        }
 
        if (old_r)
-               tcf_exts_change(tp, &r->exts, &e);
+               tcf_exts_change(&r->exts, &e);
        else
-               tcf_exts_change(tp, &cr.exts, &e);
+               tcf_exts_change(&cr.exts, &e);
 
        if (old_r && old_r != r) {
                err = tcindex_filter_result_init(old_r);
@@ -439,7 +439,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, 
unsigned long base,
                struct tcindex_filter *nfp;
                struct tcindex_filter __rcu **fp;
 
-               tcf_exts_change(tp, &f->result.exts, &r->exts);
+               tcf_exts_change(&f->result.exts, &r->exts);
 
                fp = cp->h + (handle % cp->hash);
                for (nfp = rtnl_dereference(*fp);
-- 
2.9.3