user/sven/linux.git/include/linux/tcp.h, branch v5.8.11

tcp: allow at most one TLP probe per flight

2020-07-23T19:23:32Z

Previously TLP may send multiple probes of new data in one flight. This happens when the sender is cwnd limited. After the initial TLP containing new data is sent, the sender receives another ACK that acks partial inflight. It may re-arm another TLP timer to send more, if no further ACK returns before the next TLP timeout (PTO) expires. The sender may send in theory a large amount of TLP until send queue is depleted. This only happens if the sender sees such irregular uncommon ACK pattern. But it is generally undesirable behavior during congestion especially. The original TLP design restrict only one TLP probe per inflight as published in "Reducing Web Latency: the Virtue of Gentle Aggression", SIGCOMM 2013. This patch changes TLP to send at most one probe per inflight. Note that if the sender is app-limited, TLP retransmits old data and did not have this issue. Signed-off-by: Yuchung Cheng Signed-off-by: Neal Cardwell Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: add tcp_sock_set_keepcnt

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_KEEPCNT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

tcp: add tcp_sock_set_keepintvl

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_KEEPINTVL sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

tcp: add tcp_sock_set_keepidle

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_KEEP_IDLE sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

tcp: add tcp_sock_set_user_timeout

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_USER_TIMEOUT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

tcp: add tcp_sock_set_syncnt

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_SYNCNT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Acked-by: Sagi Grimberg Signed-off-by: David S. Miller

tcp: add tcp_sock_set_quickack

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_QUICKACK sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

tcp: add tcp_sock_set_nodelay

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_NODELAY sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig Acked-by: Sagi Grimberg Acked-by: Jason Gunthorpe Signed-off-by: David S. Miller

tcp: add tcp_sock_set_cork

2020-05-28T18:11:45Z

Add a helper to directly set the TCP_CORK sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

mptcp: add new sock flag to deal with join subflows

2020-05-15T19:30:13Z

MP_JOIN subflows must not land into the accept queue. Currently tcp_check_req() calls an mptcp specific helper to detect such scenario. Such helper leverages the subflow context to check for MP_JOIN subflows. We need to deal also with MP JOIN failures, even when the subflow context is not available due allocation failure. A possible solution would be changing the syn_recv_sock() signature to allow returning a more descriptive action/ error code and deal with that in tcp_check_req(). Since the above need is MPTCP specific, this patch instead uses a TCP request socket hole to add a MPTCP specific flag. Such flag is used by the MPTCP syn_recv_sock() to tell tcp_check_req() how to deal with the request socket. This change is a no-op for !MPTCP build, and makes the MPTCP code simpler. It allows also the next patch to deal correctly with MP JOIN failure. v1 -> v2: - be more conservative on drop_req initialization (Mat) RFC -> v1: - move the drop_req bit inside tcp_request_sock (Eric) Signed-off-by: Paolo Abeni Reviewed-by: Mat Martineau Reviewed-by: Christoph Paasch Signed-off-by: David S. Miller