On Fri, Sep 20, 2019 at 12:49 AM Steffen Klassert
[off-list ref] wrote:
quoted hunk ↗ jump to hunk
This patch enables UDP GRO regardless if a GRO capable
socket is present. With this GRO is done by default
for the local input and forwarding path.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index a3908e55ed89..929b12fc7bc5 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -401,36 +401,25 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head,
return NULL;
}
-INDIRECT_CALLABLE_DECLARE(struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
- __be16 sport, __be16 dport));
struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
- struct udphdr *uh, udp_lookup_t lookup)
+ struct udphdr *uh, struct sock *sk)
{
struct sk_buff *pp = NULL;
struct sk_buff *p;
struct udphdr *uh2;
unsigned int off = skb_gro_offset(skb);
int flush = 1;
- struct sock *sk;
- rcu_read_lock();
- sk = INDIRECT_CALL_INET(lookup, udp6_lib_lookup_skb,
- udp4_lib_lookup_skb, skb, uh->source, uh->dest);
- if (!sk)
- goto out_unlock;
-
- if (udp_sk(sk)->gro_enabled) {
+ if (!sk || !udp_sk(sk)->gro_receive) {
Not critical, but the use of sk->gro_enabled and sk->gro_receive to
signal whether sockets are willing to accept large packets or are udp
tunnels, respectively, is subtle and possibly confusing.
Wrappers udp_sock_is_tunnel and udp_sock_accepts_gso could perhaps
help document the logic a bit.
static inline bool udp_sock_is_tunnel(struct udp_sock *up)
{
return up->gro_receive;
}
And perhaps only pass a non-zero sk to udp_gro_receive if it is a
tunnel and thus skips the new default path:
static inline struct sock *sk = udp4_lookup_tunnel(const struct
sk_buff *skb, __be16 sport, __be16_dport)
{
struct sock *sk;
if (!static_branch_unlikely(&udp_encap_needed_key))
return NULL;
rcu_read_lock();
sk = udp4_lib_lookup_skb(skb, source, dest);
rcu_read_unlock();
return udp_sock_is_tunnel(udp_sk(sk)) ? sk : NULL;
}
quoted hunk ↗ jump to hunk
pp = call_gro_receive(udp_gro_receive_segment, head, skb);
- rcu_read_unlock();
return pp;
}
Just a suggestion. It may be too verbose as given.
quoted hunk ↗ jump to hunk
@@ -468,8 +456,10 @@ INDIRECT_CALLABLE_SCOPE
struct sk_buff *udp4_gro_receive(struct list_head *head, struct sk_buff *skb)
{
struct udphdr *uh = udp_gro_udphdr(skb);
+ struct sk_buff *pp;
+ struct sock *sk;
- if (unlikely(!uh) || !static_branch_unlikely(&udp_encap_needed_key))
+ if (unlikely(!uh))
goto flush;
/* Don't bother verifying checksum if we're going to flush anyway. */@@ -484,7 +474,11 @@ struct sk_buff *udp4_gro_receive(struct list_head *head, struct sk_buff *skb)
inet_gro_compute_pseudo);
skip:
NAPI_GRO_CB(skb)->is_ipv6 = 0;
- return udp_gro_receive(head, skb, uh, udp4_lib_lookup_skb);
+ rcu_read_lock();
+ sk = static_branch_unlikely(&udp_encap_needed_key) ? udp4_lib_lookup_skb(skb, uh->source, uh->dest) : NULL;
+ pp = udp_gro_receive(head, skb, uh, sk);
+ rcu_read_unlock();
+ return pp;