On Thu, Mar 26, 2020 at 8:14 AM Marcelo Ricardo Leitner
[off-list ref] wrote:

On Sun, Mar 22, 2020 at 05:04:25PM +0800, Qiujun Huang wrote:

quoted

sctp_sock_migrate should iterate over the datamsgs to modify
all trunks(skbs) to newsk. For this, out_msg_list is added to

s/trunks/chunks/

My :p.

quoted

sctp_outq to maintain datamsgs list.

It is an interesting approach. It speeds up the migration, yes, but it
will also use more memory per datamsg, for an operation that, when
performed, the socket is usually calm.

It's also another list to be handled, and I'm not seeing the patch
here move the datamsg itself now to the new outq. It would need
something along these lines:

Are all the rx chunks in the rx queues?

sctp_sock_migrate()
{
...
        /* Move any messages in the old socket's receive queue that are for the
         * peeled off association to the new socket's receive queue.
         */
        sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
                event = sctp_skb2event(skb);
...
                /* Walk through the pd_lobby, looking for skbs that
                 * need moved to the new socket.
                 */
                sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
                        event = sctp_skb2event(skb);

That said, I don't think it's worth this new list.

About this case:
datamsg
                   ->chunk0                       chunk1
       chunk2
 queue          ->transmitted                 ->retransmit
 ->not in any queue

Also need to maintain a datamsg list to record which datamsg is
processed avoiding repetitive
processing.
So, list it to outq. Maybe it will be used sometime.

  Marcelo