[bpf-next,v5,09/11] bpf: Add BPF_SOCK_OPS_RETRANS_CB

Message ID	20180109210704.893375-10-brakmo@fb.com
State	Changes Requested, archived
Delegated to:	BPF Maintainers
Headers	show Return-Path: <netdev-owner@vger.kernel.org> Smtp-Origin-Hostprefix: dev From: Lawrence Brakmo <brakmo@fb.com> Smtp-Origin-Hostname: dev15893.prn1.facebook.com To: netdev <netdev@vger.kernel.org> CC: Kernel Team <kernel-team@fb.com>, Blake Matheny <bmatheny@fb.com>, "Alexei Starovoitov" <ast@fb.com>, Daniel Borkmann <daniel@iogearbox.net>, "Eric Dumazet" <eric.dumazet@gmail.com>, Neal Cardwell <ncardwell@google.com>, Yuchung Cheng <ycheng@google.com> Smtp-Origin-Cluster: prn1c29 Subject: [PATCH bpf-next v5 09/11] bpf: Add BPF_SOCK_OPS_RETRANS_CB Date: Tue, 9 Jan 2018 13:07:02 -0800 Message-ID: <20180109210704.893375-10-brakmo@fb.com> In-Reply-To: <20180109210704.893375-1-brakmo@fb.com> References: <20180109210704.893375-1-brakmo@fb.com> MIME-Version: 1.0 Content-Type: text/plain Sender: netdev-owner@vger.kernel.org Precedence: bulk
Series	bpf: More sock_ops callbacks \| expand [bpf-next,v5,00/11] bpf: More sock_ops callbacks [bpf-next,v5,01/11] bpf: Make SOCK_OPS_GET_TCP size independent [bpf-next,v5,02/11] bpf: Make SOCK_OPS_GET_TCP struct independent [bpf-next,v5,03/11] bpf: Add write access to tcp_sock and sock fields [bpf-next,v5,04/11] bpf: Support passing args to sock_ops bpf function [bpf-next,v5,05/11] bpf: Adds field bpf_sock_ops_flags to tcp_sock [bpf-next,v5,06/11] bpf: Add sock_ops RTO callback [bpf-next,v5,07/11] bpf: Add support for reading sk_state and more [bpf-next,v5,08/11] bpf: Add sock_ops R/W access to tclass & sk_txhash [bpf-next,v5,09/11] bpf: Add BPF_SOCK_OPS_RETRANS_CB [bpf-next,v5,10/11] bpf: Add BPF_SOCK_OPS_STATE_CB [bpf-next,v5,11/11] bpf: add selftest for tcpbpf

Message ID

20180109210704.893375-10-brakmo@fb.com

State

Changes Requested, archived

Delegated to:

BPF Maintainers

Headers

Smtp-Origin-Hostprefix: dev
From: Lawrence Brakmo <brakmo@fb.com>
Smtp-Origin-Hostname: dev15893.prn1.facebook.com
To: netdev <netdev@vger.kernel.org>
CC: Kernel Team <kernel-team@fb.com>, Blake Matheny <bmatheny@fb.com>,
	"Alexei Starovoitov" <ast@fb.com>,
	Daniel Borkmann <daniel@iogearbox.net>,
	"Eric Dumazet" <eric.dumazet@gmail.com>,
	Neal Cardwell <ncardwell@google.com>, Yuchung Cheng <ycheng@google.com>
Smtp-Origin-Cluster: prn1c29
Subject: [PATCH bpf-next v5 09/11] bpf: Add BPF_SOCK_OPS_RETRANS_CB
Date: Tue, 9 Jan 2018 13:07:02 -0800
Message-ID: <20180109210704.893375-10-brakmo@fb.com>
In-Reply-To: <20180109210704.893375-1-brakmo@fb.com>
References: <20180109210704.893375-1-brakmo@fb.com>
MIME-Version: 1.0
Content-Type: text/plain
Sender: netdev-owner@vger.kernel.org
Precedence: bulk

Series

bpf: More sock_ops callbacks | expand

Commit Message

Lawrence Brakmo Jan. 9, 2018, 9:07 p.m. UTC

Adds support for calling sock_ops BPF program when there is a
retransmission. Two arguments are used; one for the sequence number and
other for the number of segments retransmitted. Does not include syn-ack
retransmissions.

New op: BPF_SOCK_OPS_RETRANS_CB.

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
---
 include/uapi/linux/bpf.h | 4 ++++
 include/uapi/linux/tcp.h | 1 +
 net/ipv4/tcp_output.c    | 3 +++
 3 files changed, 8 insertions(+)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index b5f698f..5b804bc 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1026,6 +1026,10 @@  enum {
 					 * Arg2: value of icsk_rto
 					 * Arg3: whether RTO has expired
 					 */
+	BPF_SOCK_OPS_RETRANS_CB,	/* Called when skb is retransmitted.
+					 * Arg1: sequence number of 1st byte
+					 * Arg2: # segments
+					 */
 };
 
 #define TCP_BPF_IW		1001	/* Set TCP initial congestion window */
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
index 089c19e..dc36d3c 100644
--- a/include/uapi/linux/tcp.h
+++ b/include/uapi/linux/tcp.h
@@ -261,6 +261,7 @@  struct tcp_md5sig {
 
 /* Definitions for bpf_sock_ops_flags */
 #define BPF_SOCK_OPS_RTO_CB_FLAG	(1<<0)
+#define BPF_SOCK_OPS_RETRANS_CB_FLAG	(1<<1)
 
 /* INET_DIAG_MD5SIG */
 struct tcp_diag_md5sig {
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index b093985..8109675 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2907,6 +2907,9 @@  int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
 	if (likely(!err)) {
 		TCP_SKB_CB(skb)->sacked |= TCPCB_EVER_RETRANS;
 		trace_tcp_retransmit_skb(sk, skb);
+		if (BPF_SOCK_OPS_TEST_FLAG(tp, BPF_SOCK_OPS_RETRANS_CB_FLAG))
+			tcp_call_bpf_2arg(sk, BPF_SOCK_OPS_RETRANS_CB,
+					  TCP_SKB_CB(skb)->seq, segs);
 	} else if (err != -EBUSY) {
 		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL);
 	}

[bpf-next,v5,09/11] bpf: Add BPF_SOCK_OPS_RETRANS_CB

Commit Message

Patch