W dniu 9/16/25 o 12:49, Sabrina Dubroca pisze: > 2025-09-12, 13:24:20 +0200, Marek Mietus wrote: >> ovpn_udp4_output unnecessarily references the dst_entry from the >> dst_cache. > > This should probably include a description of why it's safe to skip > the reference in this context. >
Noted, will do. >> Reduce this overhead by using the newly implemented >> udp_tunnel_xmit_skb_noref function and dst_cache helpers. >> >> Signed-off-by: Marek Mietus <[email protected]> >> --- >> drivers/net/ovpn/udp.c | 12 ++++++------ >> 1 file changed, 6 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c >> index d6a0f7a0b75d..c5d289c23d2b 100644 >> --- a/drivers/net/ovpn/udp.c >> +++ b/drivers/net/ovpn/udp.c >> @@ -158,7 +158,7 @@ static int ovpn_udp4_output(struct ovpn_peer *peer, >> struct ovpn_bind *bind, >> int ret; >> >> local_bh_disable(); >> - rt = dst_cache_get_ip4(cache, &fl.saddr); >> + rt = dst_cache_get_ip4_rcu(cache, &fl.saddr); >> if (rt) >> goto transmit; >> >> @@ -194,12 +194,12 @@ static int ovpn_udp4_output(struct ovpn_peer *peer, >> struct ovpn_bind *bind, >> ret); >> goto err; >> } >> - dst_cache_set_ip4(cache, &rt->dst, fl.saddr); >> + dst_cache_steal_ip4(cache, &rt->dst, fl.saddr); >> >> transmit: >> - udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0, >> - ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport, >> - fl.fl4_dport, false, sk->sk_no_check_tx, 0); >> + udp_tunnel_xmit_skb_noref(rt, sk, skb, fl.saddr, fl.daddr, 0, >> + ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport, >> + fl.fl4_dport, false, sk->sk_no_check_tx, 0); >> ret = 0; >> err: >> local_bh_enable(); >> @@ -269,7 +269,7 @@ static int ovpn_udp6_output(struct ovpn_peer *peer, >> struct ovpn_bind *bind, >> * fragment packets if needed. >> * >> * NOTE: this is not needed for IPv4 because we pass df=0 to >> - * udp_tunnel_xmit_skb() >> + * udp_tunnel_xmit_skb_noref() >> */ >> skb->ignore_df = 1; >> udp_tunnel6_xmit_skb(dst, sk, skb, skb->dev, &fl.saddr, &fl.daddr, 0, > > Why are you changing only ipv4? Is there something in the ipv6 code > that prevents this? > I'm not sure. I'm not as acquainted with IPv6 as I am with IPv4. (and thought I'd hold off until I got a positive response about the series) IPv4 already has some noref xmit optimizations, so it just felt like the right place to start. _______________________________________________ Openvpn-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openvpn-devel
