From: David Morley morleyd@google.com
[ Upstream commit 300b655db1b5152d6101bcb6801d50899b20c2d6 ]
The initial default value of 0 for tp->rate_app_limited was incorrect, since a flow is indeed application-limited until it first sends data. Fixing the default to be 1 is generally correct but also specifically will help user-space applications avoid using the initial tcpi_delivery_rate value of 0 that persists until the connection has some non-zero bandwidth sample.
Fixes: eb8329e0a04d ("tcp: export data delivery rate") Suggested-by: Yuchung Cheng ycheng@google.com Signed-off-by: David Morley morleyd@google.com Signed-off-by: Neal Cardwell ncardwell@google.com Tested-by: David Morley morleyd@google.com Reviewed-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/tcp.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index fe1972aad279..51f34560a9d6 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -439,6 +439,7 @@ void tcp_init_sock(struct sock *sk)
/* There's a bubble in the pipe until at least the first ACK. */ tp->app_limited = ~0U; + tp->rate_app_limited = 1;
/* See draft-stevens-tcpca-spec-01 for discussion of the * initialization of these values. @@ -3066,6 +3067,7 @@ int tcp_disconnect(struct sock *sk, int flags) tp->last_oow_ack_time = 0; /* There's a bubble in the pipe until at least the first ACK. */ tp->app_limited = ~0U; + tp->rate_app_limited = 1; tp->rack.mstamp = 0; tp->rack.advanced = 0; tp->rack.reo_wnd_steps = 1;