From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F234628EB for ; Mon, 30 Jan 2023 14:02:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 76CA4C433EF; Mon, 30 Jan 2023 14:02:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675087323; bh=YX4RugcpItiVM8A7NG6e5fEYq5hgkGcvBR9y9xKIkjc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a4FMsrDHVjtn5O+wz0iRtDHzxG9N6izejiuxyYNZ3bpuAkYYjsYwHRrkl9Q+I2vMZ lNcODFbWkXawdpeM71mWEXF7k0o3pAfY34pe8zYLcxvbxOWNM22Br0U9oTdlKo+mny r9lfaT+LwMSTYebUwRcwPf/b/yMBHG9bTJc/M7SY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuchung Cheng , David Morley , Neal Cardwell , Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 6.1 140/313] tcp: fix rate_app_limited to default to 1 Date: Mon, 30 Jan 2023 14:49:35 +0100 Message-Id: <20230130134343.174504672@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230130134336.532886729@linuxfoundation.org> References: <20230130134336.532886729@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: David Morley [ 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 Signed-off-by: David Morley Signed-off-by: Neal Cardwell Tested-by: David Morley Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 4f2205756cfe..ec19ed722453 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -435,6 +435,7 @@ 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. @@ -3177,6 +3178,7 @@ 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; -- 2.39.0