cgroup: initialize cgrp_dfl_root_inhibit_ss_mask from !->dfl_files test
cgrp_dfl_root_inhibit_ss_mask determines which subsystems are not
supported on the default hierarchy and is currently initialized
statically and just includes the debug subsystem. Now that there's
cgroup_subsys->dfl_files, we can easily tell which subsystems support
the default hierarchy or not.
Let's initialize cgrp_dfl_root_inhibit_ss_mask by testing whether
cgroup_subsys->dfl_files is NULL. After all, subsystems with NULL
->dfl_files aren't useable on the default hierarchy anyway.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index f41d164..f2a6795 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -156,11 +156,7 @@
static bool cgroup_legacy_files_on_dfl;
/* some controllers are not supported in the default hierarchy */
-static const unsigned int cgrp_dfl_root_inhibit_ss_mask = 0
-#ifdef CONFIG_CGROUP_DEBUG
- | (1 << debug_cgrp_id)
-#endif
- ;
+static unsigned int cgrp_dfl_root_inhibit_ss_mask;
/* The list of hierarchy roots */
@@ -4939,6 +4935,9 @@
if (cgroup_legacy_files_on_dfl && !ss->dfl_cftypes)
ss->dfl_cftypes = ss->legacy_cftypes;
+ if (!ss->dfl_cftypes)
+ cgrp_dfl_root_inhibit_ss_mask |= 1 << ss->id;
+
if (ss->dfl_cftypes == ss->legacy_cftypes) {
WARN_ON(cgroup_add_cftypes(ss, ss->dfl_cftypes));
} else {