W dniu 2017-09-21 o 13:31, Paweł Staszewski pisze:
W dniu 2017-09-21 o 13:03, Eric Dumazet pisze:
OK we have two problems here
1) We need to unify skb_dst_force() ( for net tree )
2) Vlan devices should try to correctly handle IFF_XMIT_DST_RELEASE from
lower device. This will considerably help your performance.
For 1), this is what I had in mind, can you try it ?
Thanks a lot !
diff --git a/include/net/dst.h b/include/net/dst.h
index
93568bd0a3520bb7402f04d90cf04ac99c81cfbe..f23851eeaad917e8dafc06b58d23a2575405c894
100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -271,7 +271,7 @@ static inline void dst_use_noref(struct dst_entry
*dst, unsigned long time)
static inline struct dst_entry *dst_clone(struct dst_entry *dst)
{
if (dst)
- atomic_inc(&dst->__refcnt);
+ dst_hold(dst);
return dst;
}
@@ -311,21 +311,6 @@ static inline void skb_dst_copy(struct sk_buff
*nskb, const struct sk_buff *oskb
__skb_dst_copy(nskb, oskb->_skb_refdst);
}
-/**
- * skb_dst_force - makes sure skb dst is refcounted
- * @skb: buffer
- *
- * If dst is not yet refcounted, let's do it
- */
-static inline void skb_dst_force(struct sk_buff *skb)
-{
- if (skb_dst_is_noref(skb)) {
- WARN_ON(!rcu_read_lock_held());
- skb->_skb_refdst &= ~SKB_DST_NOREF;
- dst_clone(skb_dst(skb));
- }
-}
-
/**
* dst_hold_safe - Take a reference on a dst if possible
* @dst: pointer to dst entry
@@ -356,6 +341,23 @@ static inline void skb_dst_force_safe(struct
sk_buff *skb)
}
}
+/**
+ * skb_dst_force - makes sure skb dst is refcounted
+ * @skb: buffer
+ *
+ * If dst is not yet refcounted, let's do it
+ */
+static inline void skb_dst_force(struct sk_buff *skb)
+{
+ if (skb_dst_is_noref(skb)) {
+ struct dst_entry *dst = skb_dst(skb);
+
+ WARN_ON(!rcu_read_lock_held());
+ if (!dst_hold_safe(dst))
+ dst = NULL;
+ skb->_skb_refdst = (unsigned long)dst;
+ }
+}
/**
* __skb_tunnel_rx - prepare skb for rx reinsert
Patch applied - soo far no problems - and no warnings in dmesg
ok after adding patch all is working from now for about 1 hour of normal
traffic witc all bgp sessions connected and about 600k prefixes in kernel.
