K 10
svn:author
V 6
kevans
K 8
svn:date
V 27
2020-12-30T01:13:56.851770Z
K 7
svn:log
V 462
grep: replace the internal queue with a ring buffer

We know up front how many items we can have in the queue (-B/Bflag), so
pay the cost of those particular allocations early on.

The reduced queue maintenance overhead seemed to yield about an ~8%
improvement for my earlier `grep -C8 -r closefrom .` test.

(cherry picked from commit df546c3b730d4abcace1da24226bd5f01280588e)

Git Hash:   a3abf665833465461030c413f07d324e7d64ae30
Git Author: kevans@FreeBSD.org
END