On Thu, Nov 14, 2013 at 09:34:55PM -0500, Vlad Yasevich wrote:On 11/14/2013 03:40 PM, Chang Xiangzhong wrote:I agree, this patch doesn't agree with the spec, the only time we transitionExpected Behavior:
When hearing an ack from a tranport/path, set its state to normal/on if it's
in abnormal(__partial_failure__ or inactive) state.
state machine of tranport->state
Whenever a T3_RTX timer expires, then transport->error_count++.
When (association->pf_retrans < transport->error_count < tranport->pathmaxrtx)
transport->state = SCTP_PF //partial failure
When a heartbeat-ack comes or conventional ack acknowledged its availability,
transport->state = SCTP_ON
Signed-off-by: Chang Xiangzhong <changxiangzhong@xxxxxxxxx>
Fixes: 5aa93bcf66f ("sctp: Implement quick failover draft from tsvwg")
I don't think this is right. The spec states:
8. ACKs for retransmissions do not transition a PF destination back
to Active state, since a sender cannot disambiguate whether the
ack was for the original transmission or the retransmission(s).
Now, the proper way to this would would be modify
sctp_assoc_control_transport() to transition the transport state to
ACTIVE if it was PF transport that was chosen to send data.
-vlad
from PF to ACTIVE should be on receipt of ack of new data.
I'm not even sure if
we should allow PF transports to be selected to send new data. Currently a
potentially failed transport will get ignored when specified, and the stack will
use the active path in its place. Only if all transports are PF will a PF
transport be chosen.
Neil
---
net/sctp/outqueue.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 94df758..2557fa5 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -1517,6 +1517,7 @@ static void sctp_check_transmitted(struct sctp_outq *q,
* active if it is not so marked.
*/
if ((transport->state == SCTP_INACTIVE ||
+ transport->state == SCTP_PF ||
transport->state == SCTP_UNCONFIRMED) &&
sctp_cmp_addr_exact(&transport->ipaddr, saddr)) {
sctp_assoc_control_transport(