drm/ttm: Improved fencing of buffer object lists

Drastically reduce the number of spin lock / unlock operations by performing
unreserving and fencing under global locks.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jerome Glisse <j.glisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
4 files changed