[PATCH bpf-next v2 2/6] tcp: bpf: support bpf_getsockopt for TCP_BPF_RTO_MIN

[Jason Xing <kerneljasonxing@xxxxxxxxx>]

Support bpf_getsockopt if application tries to know what the RTO MIN
of this socket is.

Signed-off-by: Jason Xing <kerneljasonxing@xxxxxxxxx>
---
 net/core/filter.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/core/filter.c b/net/core/filter.c
index 2932de5cc57c..4d34d35af5c7 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5295,6 +5295,12 @@ static int bpf_sol_tcp_getsockopt(struct sock *sk, int optname,
 		memcpy(optval, &cb_flags, optlen);
 		break;
 	}
+	case TCP_BPF_RTO_MIN: {
+		int rto_min_us = jiffies_to_usecs(inet_csk(sk)->icsk_rto_min);
+
+		memcpy(optval, &rto_min_us, optlen);
+		break;
+	}
 	default:
 		return -EINVAL;
 	}
-- 
2.43.5