This patch adds a testcase for DLM to create one million locks at module
load time and unlock them at the module unload time. It generates a
burst of lock/unlock requests and you could observe e.g. slabinfo or
networking connection about where the bottlenecks are regarding
performance or memory usage.

There is a module parameter cluster_name to tell which cluster to join
but DLM has some own strategy to join the first cluster if this
parameter isn't given. So just load the module with:

modprobe dlm_bursttest

on all nodes and wait until it's done, try to observe kernel log,
slabinfo, etc.

Then unload it with:

rmmod dlm_bursttest

to see how everything gets cleaned up by unlock all locks.

Signed-off-by: Alexander Aring <aahringo@redhat.com>