From: Xin Long <[email protected]>
Date: Thu, 10 Mar 2016 15:31:57 +0800
> prior to this patch, at the beginning if we have two paths in one assoc,
> they may have the same params other than the last_time_heard, it will try
> the paths like this:
>
> 1st cycle
> try trans1 fail.
> then trans2 is selected.(cause it's last_time_heard is after trans1).
>
> 2nd cycle:
> try trans2 fail
> then trans2 is selected.(cause it's last_time_heard is after trans1).
>
> 3rd cycle:
> try trans2 fail
> then trans2 is selected.(cause it's last_time_heard is after trans1).
>
> ....
>
> trans1 will never have change to be selected, which is not what we expect.
> we should keeping round robin all the paths if they are just added at the
> beginning.
>
> So at first every tranport's last_time_heard should be initialized 0, so
> that we ensure they have the same value at the beginning, only by this,
> all the transports could get equal chance to be selected.
>
> Then for sctp_trans_elect_best, it should return the trans_next one when
> *trans == *trans_next, so that we can try next if it fails, but now it
> always return trans. so we can fix it by exchanging these two params when
> we calls sctp_trans_elect_tie().
>
> Fixes: 4c47af4d5eb2 ('net: sctp: rework multihoming retransmission path
> selection to rfc4960')
> Signed-off-by: Xin Long <[email protected]>
Applied, thanks.
