diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2023-05-15 17:06:37 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-05-17 08:37:55 +0100 |
| commit | a7533584728d366f11b210d0e8a2fad03109c669 (patch) | |
| tree | ea527346b81a27e1bd3d80a2ea1ff207034e51b4 /net | |
| parent | eea96a3e2c909a055005ac65dde356b36cabc4ed (diff) | |
| download | linux-stable-a7533584728d366f11b210d0e8a2fad03109c669.tar.gz linux-stable-a7533584728d366f11b210d0e8a2fad03109c669.tar.bz2 linux-stable-a7533584728d366f11b210d0e8a2fad03109c669.zip | |
net/tcp: optimise io_uring zc ubuf refcounting
io_uring keeps a reference to ubuf_info during submission, so if
tcp_sendmsg_locked() sees msghdr::msg_ubuf in can be sure the buffer
will be kept alive and doesn't need to additionally pin it.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 40f591f7fce1..3d18e295bb2f 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1231,7 +1231,6 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) if ((flags & MSG_ZEROCOPY) && size) { if (msg->msg_ubuf) { uarg = msg->msg_ubuf; - net_zcopy_get(uarg); zc = sk->sk_route_caps & NETIF_F_SG; } else if (sock_flag(sk, SOCK_ZEROCOPY)) { skb = tcp_write_queue_tail(sk); @@ -1458,7 +1457,9 @@ out: tcp_push(sk, flags, mss_now, tp->nonagle, size_goal); } out_nopush: - net_zcopy_put(uarg); + /* msg->msg_ubuf is pinned by the caller so we don't take extra refs */ + if (uarg && !msg->msg_ubuf) + net_zcopy_put(uarg); return copied + copied_syn; do_error: @@ -1467,7 +1468,9 @@ do_error: if (copied + copied_syn) goto out; out_err: - net_zcopy_put_abort(uarg, true); + /* msg->msg_ubuf is pinned by the caller so we don't take extra refs */ + if (uarg && !msg->msg_ubuf) + net_zcopy_put_abort(uarg, true); err = sk_stream_error(sk, flags, err); /* make sure we wake any epoll edge trigger waiter */ if (unlikely(tcp_rtx_and_write_queues_empty(sk) && err == -EAGAIN)) { |