diff options
| author |   Paolo Abeni <pabeni@redhat.com> | 2017-05-16 11:20:14 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2017-05-16 15:41:29 -0400 |
| commit | 2276f58ac5890e58d2b6a48b95493faff7347e3a (patch) | |
| tree | c77ce6fd0b942dfddb145e1ad6dbb2fb1942d849 /include | |
| parent | net/sock: factor out dequeue/peek with offset code (diff) | |
| download | linux-dev-2276f58ac5890e58d2b6a48b95493faff7347e3a.tar.xz linux-dev-2276f58ac5890e58d2b6a48b95493faff7347e3a.zip | |
udp: use a separate rx queue for packet reception
under udp flood the sk_receive_queue spinlock is heavily contended.
This patch try to reduce the contention on such lock adding a
second receive queue to the udp sockets; recvmsg() looks first
in such queue and, only if empty, tries to fetch the data from
sk_receive_queue. The latter is spliced into the newly added
queue every time the receive path has to acquire the
sk_receive_queue lock.
The accounting of forward allocated memory is still protected with
the sk_receive_queue lock, so udp_rmem_release() needs to acquire
both locks when the forward deficit is flushed.
On specific scenarios we can end up acquiring and releasing the
sk_receive_queue lock multiple times; that will be covered by
the next patch
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/udp.h | 3 | ||||
| -rw-r--r-- | include/net/udp.h | 9 | ||||
| -rw-r--r-- | include/net/udplite.h | 2 |
3 files changed, 6 insertions, 8 deletions
diff --git a/include/linux/udp.h b/include/linux/udp.h index 6cb4061a720d..eaea63bc79bb 100644 --- a/include/linux/udp.h +++ b/include/linux/udp.h @@ -80,6 +80,9 @@ struct udp_sock { struct sk_buff *skb, int nhoff); + /* udp_recvmsg try to use this before splicing sk_receive_queue */ + struct sk_buff_head reader_queue ____cacheline_aligned_in_smp; + /* This field is dirtied by udp_recvmsg() */ int forward_deficit; }; diff --git a/include/net/udp.h b/include/net/udp.h index 3391dbd73959..1468dbd0f09a 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -249,13 +249,8 @@ void udp_destruct_sock(struct sock *sk); void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len); int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb); void udp_skb_destructor(struct sock *sk, struct sk_buff *skb); -static inline struct sk_buff * -__skb_recv_udp(struct sock *sk, unsigned int flags, int noblock, int *peeked, - int *off, int *err) -{ - return __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), - udp_skb_destructor, peeked, off, err); -} +struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags, + int noblock, int *peeked, int *off, int *err); static inline struct sk_buff *skb_recv_udp(struct sock *sk, unsigned int flags, int noblock, int *err) { diff --git a/include/net/udplite.h b/include/net/udplite.h index ea340524f99b..b7a18f63d86d 100644 --- a/include/net/udplite.h +++ b/include/net/udplite.h @@ -26,8 +26,8 @@ static __inline__ int udplite_getfrag(void *from, char *to, int offset, /* Designate sk as UDP-Lite socket */ static inline int udplite_sk_init(struct sock *sk) { + udp_init_sock(sk); udp_sk(sk)->pcflag = UDPLITE_BIT; - sk->sk_destruct = udp_destruct_sock; return 0; } |