From: Paolo Abeni <pab...@redhat.com> This makes mptcp sendmsg() behaviour more consistent and improves xmit performances.
Signed-off-by: Paolo Abeni <pab...@redhat.com> --- net/mptcp/protocol.c | 126 ++++++++++++++++++++++++------------------- 1 file changed, 71 insertions(+), 55 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index da983ea4fb5e..758369256f9b 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -58,71 +58,37 @@ static struct sock *mptcp_subflow_get_ref(const struct mptcp_sock *msk) return NULL; } -static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) +static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, + struct msghdr *msg, long *timeo) { int mss_now = 0, size_goal = 0, ret = 0; struct mptcp_sock *msk = mptcp_sk(sk); - struct socket *ssock; - struct sock *ssk; struct mptcp_ext *mpext = NULL; struct page_frag *pfrag; struct sk_buff *skb; size_t psize; - int poffset; - long timeo; - - lock_sock(sk); - ssock = __mptcp_fallback_get_ref(msk); - if (ssock) { - release_sock(sk); - pr_debug("fallback passthrough"); - ret = sock_sendmsg(ssock, msg); - sock_put(ssock->sk); - return ret; - } - - ssk = mptcp_subflow_get_ref(msk); - if (!ssk) { - release_sock(sk); - return -ENOTCONN; - } - - if (!msg_data_left(msg)) { - pr_debug("empty send"); - ret = sock_sendmsg(ssk->sk_socket, msg); - goto put_out; - } - - if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL)) { - ret = -ENOTSUPP; - goto put_out; - } - - lock_sock(ssk); - timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); /* use the mptcp page cache so that we can easily move the data * from one substream to another, but do per subflow memory accounting */ pfrag = sk_page_frag(sk); while (!sk_page_frag_refill(ssk, pfrag)) { - ret = sk_stream_wait_memory(ssk, &timeo); + ret = sk_stream_wait_memory(ssk, timeo); if (ret) - goto put_out; + return ret; } - /* Copy to page */ - poffset = pfrag->offset; + /* compute copy limit */ + mss_now = tcp_send_mss(ssk, &size_goal, msg->msg_flags); + psize = min_t(int, pfrag->size - pfrag->offset, size_goal); + pr_debug("left=%zu", msg_data_left(msg)); - psize = copy_page_from_iter(pfrag->page, poffset, - min_t(size_t, msg_data_left(msg), - pfrag->size - poffset), + psize = copy_page_from_iter(pfrag->page, pfrag->offset, + min_t(size_t, msg_data_left(msg), psize), &msg->msg_iter); pr_debug("left=%zu", msg_data_left(msg)); - if (!psize) { - ret = -EINVAL; - goto put_out; - } + if (!psize) + return -EINVAL; /* Mark the end of the previous write so the beginning of the * next write (with its own mptcp skb extension data) is not @@ -132,20 +98,15 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if (skb) TCP_SKB_CB(skb)->eor = 1; - mss_now = tcp_send_mss(ssk, &size_goal, msg->msg_flags); - psize = min_t(int, size_goal, psize); - ret = do_tcp_sendpages(ssk, pfrag->page, poffset, psize, + ret = do_tcp_sendpages(ssk, pfrag->page, pfrag->offset, psize, msg->msg_flags | MSG_SENDPAGE_NOTLAST); if (ret <= 0) - goto put_out; - - if (skb == tcp_write_queue_tail(ssk)) - pr_err("no new skb %p/%p", sk, ssk); + return ret; + if (unlikely(ret < psize)) + iov_iter_revert(&msg->msg_iter, psize - ret); skb = tcp_write_queue_tail(ssk); - mpext = skb_ext_add(skb, SKB_EXT_MPTCP); - if (mpext) { memset(mpext, 0, sizeof(*mpext)); mpext->data_seq = msk->write_seq; @@ -165,6 +126,61 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) mptcp_subflow_ctx(ssk)->rel_write_seq += ret; tcp_push(ssk, msg->msg_flags, mss_now, tcp_sk(ssk)->nonagle, size_goal); + return ret; +} + +static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) +{ + struct mptcp_sock *msk = mptcp_sk(sk); + struct socket *ssock; + size_t copied = 0; + struct sock *ssk; + int ret = 0; + long timeo; + + lock_sock(sk); + ssock = __mptcp_fallback_get_ref(msk); + if (ssock) { + release_sock(sk); + pr_debug("fallback passthrough"); + ret = sock_sendmsg(ssock, msg); + sock_put(ssock->sk); + return ret; + } + + ssk = mptcp_subflow_get_ref(msk); + if (!ssk) { + release_sock(sk); + return -ENOTCONN; + } + + if (!msg_data_left(msg)) { + pr_debug("empty send"); + ret = sock_sendmsg(ssk->sk_socket, msg); + goto put_out; + } + + pr_debug("conn_list->subflow=%p", ssk); + + if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL)) { + ret = -ENOTSUPP; + goto put_out; + } + + lock_sock(ssk); + timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); + while (msg_data_left(msg)) { + ret = mptcp_sendmsg_frag(sk, ssk, msg, &timeo); + if (ret < 0) + break; + + copied += ret; + } + + if (copied > 0) + ret = copied; + + release_sock(ssk); put_out: release_sock(sk); -- 2.23.0