They are not completely free of cost when disabled and
when enabled emitting debug output for every command
submitted produces far too much output to be useful.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Reviewed-by: NMike Miller <michael.miller@canonical.com>
Reviewed-by: NWebb Scales <webb.scales@hp.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>