find_cg_pool_locked
ppool = find_cg_pool_locked(parent, region);
pool = find_cg_pool_locked(p, region);
retpool = pool = find_cg_pool_locked(dmemcs, region);
ppool = find_cg_pool_locked(pp, region);
pool = find_cg_pool_locked(cg, region);
struct dmem_cgroup_pool_state *pool = find_cg_pool_locked(dmemcs, region);