Commit 01aadb3a authored by Xin Long's avatar Xin Long Committed by David S. Miller
Browse files

sctp: implement prsctp RTX policy 



prsctp RTX policy is a policy to abandon chunks when they are
retransmitted beyond the max count.

This patch uses sent_count to count how many times one chunk has
been sent, and prsctp_param is the max rtx count, which is from
sinfo->sinfo_timetolive in sctp_set_prsctp_policy(). So similar
to TTL policy, if RTX policy is enabled, msg->expire_at won't
work.

Then in sctp_chunk_abandoned, this patch checks if chunk->sent_count
is bigger than chunk->prsctp_param to abandon this chunk.

Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a6c2f792

net/sctp/chunk.c

+4 −0
Original line number Diff line number Diff line
@@ -355,6 +355,10 @@ int sctp_chunk_abandoned(struct sctp_chunk *chunk) 
		else

			chunk->asoc->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;

		return 1;

	} else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) &&

		   chunk->sent_count > chunk->prsctp_param) {

		chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++;

		return 1;

	}



	return 0;

net/sctp/sm_make_chunk.c

+2 −0
Original line number Diff line number Diff line
@@ -720,6 +720,8 @@ static void sctp_set_prsctp_policy(struct sctp_chunk *chunk, 
	if (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags))

		chunk->prsctp_param =

			jiffies + msecs_to_jiffies(sinfo->sinfo_timetolive);

	else if (SCTP_PR_RTX_ENABLED(sinfo->sinfo_flags))

		chunk->prsctp_param = sinfo->sinfo_timetolive;

}



/* Make a DATA chunk for the given association from the provided

CRA Git | Maintained and supported by SUSTech CRA and CCSE