5 files changed, 28 insertions, 4 deletions

diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 5e1694fe035b..8fcbae1b8db0 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -92,6 +92,7 @@ enum {
 
         CFTYPE_NO_PREFIX        = (1 << 3),     /* (DON'T USE FOR NEW FILES) no subsys prefix */
         CFTYPE_WORLD_WRITABLE   = (1 << 4),     /* (DON'T USE FOR NEW FILES) S_IWUGO */
+        CFTYPE_DEBUG            = (1 << 5),     /* create when cgroup_debug */
 
         /* internal flags, do not use outside cgroup core proper */
         __CFTYPE_ONLY_ON_DFL    = (1 << 16),    /* only on default hierarchy */
diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index 75568fcf2180..c950864016e2 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -11,6 +11,8 @@
 #define TRACE_CGROUP_PATH_LEN 1024
 extern spinlock_t trace_cgroup_path_lock;
 extern char trace_cgroup_path[TRACE_CGROUP_PATH_LEN];
+extern bool cgroup_debug;
+extern void __init enable_debug_cgroup(void);
 
 /*
  * cgroup_path() takes a spin lock. It is good practice not to take
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 2e5d90dfcb49..ed7f0bfe6429 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -86,6 +86,7 @@ EXPORT_SYMBOL_GPL(css_set_lock);
 
 DEFINE_SPINLOCK(trace_cgroup_path_lock);
 char trace_cgroup_path[TRACE_CGROUP_PATH_LEN];
+bool cgroup_debug __read_mostly;
 
 /*
  * Protects cgroup_idr and css_idr so that IDs can be released without
@@ -3639,7 +3640,8 @@ restart:
                         continue;
                 if ((cft->flags & CFTYPE_ONLY_ON_ROOT) && cgroup_parent(cgrp))
                         continue;
-
+                if ((cft->flags & CFTYPE_DEBUG) && !cgroup_debug)
+                        continue;
                 if (is_add) {
                         ret = cgroup_add_file(css, cgrp, cft);
                         if (ret) {
@@ -5743,6 +5745,16 @@ static int __init cgroup_disable(char *str)
 }
 __setup("cgroup_disable=", cgroup_disable);
 
+void __init __weak enable_debug_cgroup(void) { }
+
+static int __init enable_cgroup_debug(char *str)
+{
+        cgroup_debug = true;
+        enable_debug_cgroup();
+        return 1;
+}
+__setup("cgroup_debug", enable_cgroup_debug);
+
 /**
  * css_tryget_online_from_dir - get corresponding css from a cgroup dentry
  * @dentry: directory dentry of interest
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index c739fda805e0..b897314bab53 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -2204,6 +2204,7 @@ typedef enum {
         FILE_MEMLIST,
         FILE_EFFECTIVE_CPULIST,
         FILE_EFFECTIVE_MEMLIST,
+        FILE_SUBPARTS_CPULIST,
         FILE_CPU_EXCLUSIVE,
         FILE_MEM_EXCLUSIVE,
         FILE_MEM_HARDWALL,
@@ -2382,6 +2383,9 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
         case FILE_EFFECTIVE_MEMLIST:
                 seq_printf(sf, "%*pbl\n", nodemask_pr_args(&cs->effective_mems));
                 break;
+        case FILE_SUBPARTS_CPULIST:
+                seq_printf(sf, "%*pbl\n", cpumask_pr_args(cs->subparts_cpus));
+                break;
         default:
                 ret = -EINVAL;
         }
@@ -2634,6 +2638,13 @@ static struct cftype dfl_files[] = {
                 .flags = CFTYPE_NOT_ON_ROOT,
         },
 
+        {
+                .name = "cpus.subpartitions",
+                .seq_show = cpuset_common_seq_show,
+                .private = FILE_SUBPARTS_CPULIST,
+                .flags = CFTYPE_DEBUG,
+        },
+
         { }     /* terminate */
 };
 
diff --git a/kernel/cgroup/debug.c b/kernel/cgroup/debug.c
index 9caeda610249..5f1b87330bee 100644
--- a/kernel/cgroup/debug.c
+++ b/kernel/cgroup/debug.c
@@ -373,11 +373,9 @@ struct cgroup_subsys debug_cgrp_subsys = {
  * On v2, debug is an implicit controller enabled by "cgroup_debug" boot
  * parameter.
  */
-static int __init enable_cgroup_debug(char *str)
+void __init enable_debug_cgroup(void)
 {
         debug_cgrp_subsys.dfl_cftypes = debug_files;
         debug_cgrp_subsys.implicit_on_dfl = true;
         debug_cgrp_subsys.threaded = true;
-        return 1;
 }
-__setup("cgroup_debug", enable_cgroup_debug);