From 54a378f43425085d0684679d99735696b69165bc Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 7 Feb 2025 15:28:29 +0000 Subject: tcp: add the ability to control max RTO Currently, TCP stack uses a constant (120 seconds) to limit the RTO value exponential growth. Some applications want to set a lower value. Add TCP_RTO_MAX_MS socket option to set a value (in ms) between 1 and 120 seconds. It is discouraged to change the socket rto max on a live socket, as it might lead to unexpected disconnects. Following patch is adding a netns sysctl to control the default value at socket creation time. Signed-off-by: Eric Dumazet Reviewed-by: Jason Xing Reviewed-by: Neal Cardwell Reviewed-by: Kuniyuki Iwashima Signed-off-by: Paolo Abeni --- include/uapi/linux/tcp.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index dbf896f3146c..32a27b4a5020 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -136,6 +136,7 @@ enum { #define TCP_AO_REPAIR 42 /* Get/Set SNEs and ISNs */ #define TCP_IS_MPTCP 43 /* Is MPTCP being used? */ +#define TCP_RTO_MAX_MS 44 /* max rto time in ms */ #define TCP_REPAIR_ON 1 #define TCP_REPAIR_OFF 0 -- cgit v1.2.3