diff mbox series

[mptcp-next,2/3] mptcp: do not queue excessive data on subflows.

Message ID e3849a616e06bdcb75fe64895c1b50532ce34546.1610106588.git.pabeni@redhat.com
State Superseded, archived
Headers show
Series mptcp: re-enable snd buf autotune | expand

Commit Message

Paolo Abeni Jan. 8, 2021, 11:50 a.m. UTC 
The current packet scheduler can enqueue up to sndbuf
data on each subflow. If the send buffer is large and
the subflows are not symmetric, this could lead to
suboptimal aggregate bandwidth utilization.

Limit the amount of queued data to the maximum cwnd.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
 net/mptcp/protocol.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index eb6bb6b78d6f..b5b979671d92 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1414,7 +1414,7 @@  static struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk)
 			continue;
 
 		nr_active += !subflow->backup;
-		if (!sk_stream_memory_free(subflow->tcp_sock))
+		if (!sk_stream_memory_free(subflow->tcp_sock) || !tcp_sk(ssk)->snd_wnd)
 			continue;
 
 		pace = READ_ONCE(ssk->sk_pacing_rate);
@@ -1441,7 +1441,7 @@  static struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk)
 	if (send_info[0].ssk) {
 		msk->last_snd = send_info[0].ssk;
 		msk->snd_burst = min_t(int, MPTCP_SEND_BURST_SIZE,
-				       sk_stream_wspace(msk->last_snd));
+				       tcp_sk(msk->last_snd)->snd_wnd);
 		return msk->last_snd;
 	}