tree 13c1931684122480f2b2c1cc88f93b05948ac074
parent bc506fd262cdcebc6cdb0910a87cb7e4ccdd059d
author Jeremy Kerr <jk@ozlabs.org> 1486455934 +0800
committer Jeremy Kerr <jk@ozlabs.org> 1498546502 +0800

server: Use ringbuffer for socket backlog

Currently, the socket handler uses a linear buffer for the backlog data;
this means we need to shift up to 128kB of data after each socket
write().

This change introduces a single-producer-multiple-consumer ringbuffer,
to avoid the need for memmove()ing data around; we can simply update
pointers instead of shifting data.

We add this as a new file (ringbuffer.c), to make it a little more
modular. To mitigate the risk of subtle pointer arithmetic issues, we
add a set of tests too.

Change-Id: Ib7c5151d3cf1f588436f5461000b6fed22d0681c
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>