diff mbox series

[v2,net-next,3/5] mptcp: do not queue excessive data on subflows

Message ID 0ee2b775b36e79bbd46828d8fd95b0b4c030928b.1611153172.git.pabeni@redhat.com (mailing list archive)
State Accepted
Commit ec369c3a337fe075a7bd4da88d163d44c62ccbb1
Delegated to: Netdev Maintainers
Headers show
Series mptcp: re-enable sndbuf autotune | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for net-next
netdev/subject_prefix success Link
netdev/cc_maintainers warning 2 maintainers not CCed: matthieu.baerts@tessares.net mathew.j.martineau@linux.intel.com
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch warning WARNING: line length of 87 exceeds 80 columns
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Paolo Abeni Jan. 20, 2021, 2:39 p.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 send
window.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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 d07e60330df56..e741201acc98f 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1389,7 +1389,7 @@  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);
@@ -1415,7 +1415,7 @@  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;
 	}