Re: [PATCH v3] tcp: Use BPF timeout setting for SYN ACK RTO
From: Martin KaFai Lau <hidden>
Date: 2021-11-04 01:06:58
On Wed, Nov 03, 2021 at 11:46:07PM +0300, Akhmat Karakotov wrote:
quoted hunk ↗ jump to hunk
When setting RTO through BPF program, some SYN ACK packets were unaffected and continued to use TCP_TIMEOUT_INIT constant. This patch adds timeout option to struct request_sock. Option is initialized with TCP_TIMEOUT_INIT and is reassigned through BPF using tcp_timeout_init call. SYN ACK retransmits now use newly added timeout option. Signed-off-by: Akhmat Karakotov <redacted> --- include/net/request_sock.h | 2 ++ include/net/tcp.h | 2 +- net/ipv4/inet_connection_sock.c | 4 +++- net/ipv4/tcp_input.c | 8 +++++--- net/ipv4/tcp_minisocks.c | 12 +++++++++--- 5 files changed, 20 insertions(+), 8 deletions(-)diff --git a/include/net/request_sock.h b/include/net/request_sock.h index 29e41ff3ec93..144c39db9898 100644 --- a/include/net/request_sock.h +++ b/include/net/request_sock.h@@ -70,6 +70,7 @@ struct request_sock { struct saved_syn *saved_syn; u32 secid; u32 peer_secid; + u32 timeout; }; static inline struct request_sock *inet_reqsk(const struct sock *sk)@@ -104,6 +105,7 @@ reqsk_alloc(const struct request_sock_ops *ops, struct sock *sk_listener, sk_node_init(&req_to_sk(req)->sk_node); sk_tx_queue_clear(req_to_sk(req)); req->saved_syn = NULL; + req->timeout = 0; req->num_timeout = 0; req->num_retrans = 0; req->sk = NULL;diff --git a/include/net/tcp.h b/include/net/tcp.h index 3166dc15d7d6..e328d6735e38 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h@@ -2323,7 +2323,7 @@ static inline u32 tcp_timeout_init(struct sock *sk) if (timeout <= 0) timeout = TCP_TIMEOUT_INIT; - return timeout; + return min_t(int, timeout, TCP_RTO_MAX);
Acked-by: Martin KaFai Lau <redacted>