From eacf078cf4c7aa23e9591738511f142cc39b5186 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Sun, 25 Jul 2021 13:42:51 -0400 Subject: sctp: send pmtu probe only if packet loss in Search Complete state This patch is to introduce last_rtx_chunks into sctp_transport to detect if there's any packet retransmission/loss happened by checking against asoc's rtx_data_chunks in sctp_transport_pl_send(). If there is, namely, transport->last_rtx_chunks != asoc->rtx_data_chunks, the pmtu probe will be sent out. Otherwise, increment the pl.raise_count and return when it's in Search Complete state. With this patch, if in Search Complete state, which is a long period, it doesn't need to keep probing the current pmtu unless there's data packet loss. This will save quite some traffic. v1->v2: - add the missing Fixes tag. Fixes: 0dac127c0557 ("sctp: do black hole detection in search complete state") Signed-off-by: Xin Long Signed-off-by: David S. Miller --- include/net/sctp/structs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index f3d414ed208e..651bba654d77 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -984,6 +984,7 @@ struct sctp_transport { } cacc; struct { + __u32 last_rtx_chunks; __u16 pmtu; __u16 probe_size; __u16 probe_high; -- cgit v1.2.3-58-ga151