tests/logalloc_test: Ensure regions are reclaimed in order
tests/logalloc_test: Ensure regions are reclaimed in order

This test relied on task execution order to work correctly. Namely, it
relied on parent regions being reclaimed before child regions
(reclaiming is an asynchronous process started by a call to
start_reclaiming()). This order is necessary because child regions
don't know about parent regions when calculating the biggest region
that should be reclaimed.

We fix this by forcing the reclaim order.

Signed-off-by: Duarte Nunes <a60e8b7496f7715d71354fe4c06dd24017025bf1@scylladb.com>
Message-Id: <20180217121655.26057-1-a60e8b7496f7715d71354fe4c06dd24017025bf1@scylladb.com>

duarten/scylla,avikivity/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,scylladb/scylla,duarten/scylla,avikivity/scylla,duarten/scylla,scylladb/scylla