diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 86311c2907cd..70cefccd07ce 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -981,6 +981,14 @@ All cgroup core files are prefixed with "cgroup."
 		A dying cgroup can consume system resources not exceeding
 		limits, which were active at the moment of cgroup deletion.
 
+	  nr_subsys_<cgroup_subsys>
+		Total number of live cgroup subsystems (e.g memory
+		cgroup) at and beneath the current cgroup.
+
+	  nr_dying_subsys_<cgroup_subsys>
+		Total number of dying cgroup subsystems (e.g. memory
+		cgroup) at and beneath the current cgroup.
+
   cgroup.freeze
 	A read-write single value file which exists on non-root cgroups.
 	Allowed values are "0" and "1". The default is "0".
@@ -2939,8 +2947,8 @@ Deprecated v1 Core Features
 
 - "cgroup.clone_children" is removed.
 
-- /proc/cgroups is meaningless for v2.  Use "cgroup.controllers" file
-  at the root instead.
+- /proc/cgroups is meaningless for v2.  Use "cgroup.controllers" or
+  "cgroup.stat" files at the root instead.
 
 
 Issues with v1 and Rationales for v2
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index ae04035b6cbe..eb0f6f349496 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -210,6 +210,14 @@ struct cgroup_subsys_state {
 	 * fields of the containing structure.
 	 */
 	struct cgroup_subsys_state *parent;
+
+	/*
+	 * Keep track of total numbers of visible descendant CSSes.
+	 * The total number of dying CSSes is tracked in
+	 * css->cgroup->nr_dying_subsys[ssid].
+	 * Protected by cgroup_mutex.
+	 */
+	int nr_descendants;
 };
 
 /*
@@ -470,6 +478,12 @@ struct cgroup {
 	/* Private pointers for each registered subsystem */
 	struct cgroup_subsys_state __rcu *subsys[CGROUP_SUBSYS_COUNT];
 
+	/*
+	 * Keep track of total number of dying CSSes at and below this cgroup.
+	 * Protected by cgroup_mutex.
+	 */
+	int nr_dying_subsys[CGROUP_SUBSYS_COUNT];
+
 	struct cgroup_root *root;
 
 	/*
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index c8e4b62b436a..601600afdd20 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -3669,12 +3669,40 @@ static int cgroup_events_show(struct seq_file *seq, void *v)
 static int cgroup_stat_show(struct seq_file *seq, void *v)
 {
 	struct cgroup *cgroup = seq_css(seq)->cgroup;
+	struct cgroup_subsys_state *css;
+	int dying_cnt[CGROUP_SUBSYS_COUNT];
+	int ssid;
 
 	seq_printf(seq, "nr_descendants %d\n",
 		   cgroup->nr_descendants);
+
+	/*
+	 * Show the number of live and dying csses associated with each of
+	 * non-inhibited cgroup subsystems that is bound to cgroup v2.
+	 *
+	 * Without proper lock protection, racing is possible. So the
+	 * numbers may not be consistent when that happens.
+	 */
+	rcu_read_lock();
+	for (ssid = 0; ssid < CGROUP_SUBSYS_COUNT; ssid++) {
+		dying_cnt[ssid] = -1;
+		if ((BIT(ssid) & cgrp_dfl_inhibit_ss_mask) ||
+		    (cgroup_subsys[ssid]->root !=  &cgrp_dfl_root))
+			continue;
+		css = rcu_dereference_raw(cgroup->subsys[ssid]);
+		dying_cnt[ssid] = cgroup->nr_dying_subsys[ssid];
+		seq_printf(seq, "nr_subsys_%s %d\n", cgroup_subsys[ssid]->name,
+			   css ? (css->nr_descendants + 1) : 0);
+	}
+
 	seq_printf(seq, "nr_dying_descendants %d\n",
 		   cgroup->nr_dying_descendants);
-
+	for (ssid = 0; ssid < CGROUP_SUBSYS_COUNT; ssid++) {
+		if (dying_cnt[ssid] >= 0)
+			seq_printf(seq, "nr_dying_subsys_%s %d\n",
+				   cgroup_subsys[ssid]->name, dying_cnt[ssid]);
+	}
+	rcu_read_unlock();
 	return 0;
 }
 
@@ -5424,6 +5452,8 @@ static void css_release_work_fn(struct work_struct *work)
 	list_del_rcu(&css->sibling);
 
 	if (ss) {
+		struct cgroup *parent_cgrp;
+
 		/* css release path */
 		if (!list_empty(&css->rstat_css_node)) {
 			cgroup_rstat_flush(cgrp);
@@ -5433,6 +5463,14 @@ static void css_release_work_fn(struct work_struct *work)
 		cgroup_idr_replace(&ss->css_idr, NULL, css->id);
 		if (ss->css_released)
 			ss->css_released(css);
+
+		cgrp->nr_dying_subsys[ss->id]--;
+		WARN_ON_ONCE(css->nr_descendants || cgrp->nr_dying_subsys[ss->id]);
+		parent_cgrp = cgroup_parent(cgrp);
+		while (parent_cgrp) {
+			parent_cgrp->nr_dying_subsys[ss->id]--;
+			parent_cgrp = cgroup_parent(parent_cgrp);
+		}
 	} else {
 		struct cgroup *tcgrp;
 
@@ -5517,8 +5555,11 @@ static int online_css(struct cgroup_subsys_state *css)
 		rcu_assign_pointer(css->cgroup->subsys[ss->id], css);
 
 		atomic_inc(&css->online_cnt);
-		if (css->parent)
+		if (css->parent) {
 			atomic_inc(&css->parent->online_cnt);
+			while ((css = css->parent))
+				css->nr_descendants++;
+		}
 	}
 	return ret;
 }
@@ -5540,6 +5581,16 @@ static void offline_css(struct cgroup_subsys_state *css)
 	RCU_INIT_POINTER(css->cgroup->subsys[ss->id], NULL);
 
 	wake_up_all(&css->cgroup->offline_waitq);
+
+	css->cgroup->nr_dying_subsys[ss->id]++;
+	/*
+	 * Parent css and cgroup cannot be freed until after the freeing
+	 * of child css, see css_free_rwork_fn().
+	 */
+	while ((css = css->parent)) {
+		css->nr_descendants--;
+		css->cgroup->nr_dying_subsys[ss->id]++;
+	}
 }
 
 /**