net: tcp: Preallocate TX packet for TCP context
TCP context cannot operate w/o a TX packet for buffering transmitted
data. So far this net_pkt was allocated at runtime from the common
packet pool, but this created some not-obvious memory requirement on TCP
and could lead to TX packet starvation in case many TCP connections are
open in parallel. Therefore, allocate this packet structure statically,
as a part of the TCP context instead.
This increases the memory requirement of the TCP context by ~64 bytes,
however if that's a concern for the application, the maximum number of
TX packets can be lowered instead. In return, we get a clear separation
between the number of TCP connections opened, and the amount of packets
that can be transmitted.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
(cherry picked from commit eda76ad21b1748725c6d590204ee25d88caa9a82)
2 files changed
