tree 4fc9ae42e841d6402906a12bf1dbd1594c179b3a
parent addaebccf63a8c9f7c7a62ce1ceb9da4307c5a1c
author Peter Hurley <peter@hurleysoftware.com> 1371305063 -0400
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1374624141 -0700

n_tty: Replace echo_cnt with computed value

Prepare for lockless echo_buf handling; compute current byte count
of echo_buf from head and tail indices.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>