The only user is cgwb_bdi_init and that one depends on CONFIG_CGROUP_WRITEBACK which in turn depends on CONFIG_MEMCG so it doesn't make much sense to definte an empty stub for !CONFIG_MEMCG. Moreover ERR_PTR(-EINVAL) is ugly and would lead to runtime crashes if used in unguarded code paths. Better fail during compilation.
Reviewed-by: Vladimir Davydov <vdavy...@parallels.com> Signed-off-by: Michal Hocko <mho...@kernel.org> --- include/linux/memcontrol.h | 2 -- 1 file changed, 2 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 42f118ae04cf..292e6701f3fd 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -497,8 +497,6 @@ void mem_cgroup_split_huge_fixup(struct page *head); #else /* CONFIG_MEMCG */ struct mem_cgroup; -#define mem_cgroup_root_css ((struct cgroup_subsys_state *)ERR_PTR(-EINVAL)) - static inline void mem_cgroup_events(struct mem_cgroup *memcg, enum mem_cgroup_events_index idx, unsigned int nr) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/