net_sched: optimize tcf_match_indev()

tcf_match_indev() is called in fast path, it is not wise to
search for a netdev by ifindex and then compare by its name,
just compare the ifindex.

Also, dev->name could be changed by user-space, therefore
the match would be always fail, but dev->ifindex could
be consistent.

BTW, this will also save some bytes from the core struct of u32.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 7 deletions

diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index d605285af5bf..ca662aaa5eb4 100644
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -41,7 +41,7 @@ struct fw_filter {
         u32                     id;
         struct tcf_result       res;
 #ifdef CONFIG_NET_CLS_IND
-        char                    indev[IFNAMSIZ];
+        int                     ifindex;
 #endif /* CONFIG_NET_CLS_IND */
         struct tcf_exts         exts;
 };
@@ -86,7 +86,7 @@ static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,
                         if (f->id == id) {
                                 *res = f->res;
 #ifdef CONFIG_NET_CLS_IND
-                                if (!tcf_match_indev(skb, f->indev))
+                                if (!tcf_match_indev(skb, f->ifindex))
                                         continue;
 #endif /* CONFIG_NET_CLS_IND */
                                 r = tcf_exts_exec(skb, &f->exts, res);
@@ -207,9 +207,11 @@ fw_change_attrs(struct net *net, struct tcf_proto *tp, struct fw_filter *f,
 
 #ifdef CONFIG_NET_CLS_IND
         if (tb[TCA_FW_INDEV]) {
-                err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV]);
-                if (err < 0)
+                int ret;
+                ret = tcf_change_indev(net, tb[TCA_FW_INDEV]);
+                if (ret < 0)
                         goto errout;
+                f->ifindex = ret;
         }
 #endif /* CONFIG_NET_CLS_IND */
 
@@ -348,9 +350,12 @@ static int fw_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
             nla_put_u32(skb, TCA_FW_CLASSID, f->res.classid))
                 goto nla_put_failure;
 #ifdef CONFIG_NET_CLS_IND
-        if (strlen(f->indev) &&
-            nla_put_string(skb, TCA_FW_INDEV, f->indev))
-                goto nla_put_failure;
+        if (f->ifindex) {
+                struct net_device *dev;
+                dev = __dev_get_by_index(net, f->ifindex);
+                if (dev && nla_put_string(skb, TCA_FW_INDEV, dev->name))
+                        goto nla_put_failure;
+        }
 #endif /* CONFIG_NET_CLS_IND */
         if (head->mask != 0xFFFFFFFF &&
             nla_put_u32(skb, TCA_FW_MASK, head->mask))