tree 38b54a3745e355704c3c4215b3e16186dc68f92a
parent 141982a4e1a746ce3a24fbf1530763df653e96fb
author Frédéric Lécaille <flecaille@haproxy.com> 1647512890 +0100
committer Amaury Denoyelle <adenoyelle@haproxy.com> 1647858580 +0100

MEDIUM: quic: Rework of the TX packets memory handling

The TX packet refcounting had come with the multithreading support but not only.
It is very useful to ease the management of the memory allocated for TX packets
with TX frames attached to. At some locations of the code we have to move TX
frames from a packet to a new one during retranmission when the packet has been
deemed as lost or not. When deemed lost the memory allocated for the paquet must
be released contrary to when its frames are retransmitted when probing (PTO).

For now on, thanks to this patch we handle the TX packets memory this way. We
increment the packet refcount when:
  - we insert it in its packet number space tree,
  - we attache an ack-eliciting frame to it.
And reciprocally we decrement this refcount when:
  - we remove an ack-eliciting frame from the packet,
  - we delete the packet from its packet number space tree.

Note that an optimization WOULD NOT be to fully reuse (without releasing its
memorya TX packet to retransmit its contents (its ack-eliciting frames). Its
information (timestamp, in flight length) to be processed by packet loss detection
and the congestion control.