1 files changed, 918 insertions, 199 deletions

diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index 9257bd9dc664..a869d4a073c5 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -32,17 +32,25 @@
 
 #include <uapi/linux/magic.h>
 
-#include <asm/intel_rdt.h>
-#include <asm/intel_rdt_common.h>
+#include <asm/intel_rdt_sched.h>
+#include "intel_rdt.h"
 
 DEFINE_STATIC_KEY_FALSE(rdt_enable_key);
-struct kernfs_root *rdt_root;
+DEFINE_STATIC_KEY_FALSE(rdt_mon_enable_key);
+DEFINE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
+static struct kernfs_root *rdt_root;
 struct rdtgroup rdtgroup_default;
 LIST_HEAD(rdt_all_groups);
 
 /* Kernel fs node for "info" directory under root */
 static struct kernfs_node *kn_info;
 
+/* Kernel fs node for "mon_groups" directory under root */
+static struct kernfs_node *kn_mongrp;
+
+/* Kernel fs node for "mon_data" directory under root */
+static struct kernfs_node *kn_mondata;
+
 /*
  * Trivial allocator for CLOSIDs. Since h/w only supports a small number,
  * we can keep a bitmap of free CLOSIDs in a single integer.
@@ -66,7 +74,7 @@ static void closid_init(void)
 	int rdt_min_closid = 32;
 
 	/* Compute rdt_min_closid across all resources */
-	for_each_enabled_rdt_resource(r)
+	for_each_alloc_enabled_rdt_resource(r)
 		rdt_min_closid = min(rdt_min_closid, r->num_closid);
 
 	closid_free_map = BIT_MASK(rdt_min_closid) - 1;
@@ -75,9 +83,9 @@ static void closid_init(void)
 	closid_free_map &= ~1;
 }
 
-int closid_alloc(void)
+static int closid_alloc(void)
 {
-	int closid = ffs(closid_free_map);
+	u32 closid = ffs(closid_free_map);
 
 	if (closid == 0)
 		return -ENOSPC;
@@ -125,28 +133,6 @@ static int rdtgroup_add_file(struct kernfs_node *parent_kn, struct rftype *rft)
 	return 0;
 }
 
-static int rdtgroup_add_files(struct kernfs_node *kn, struct rftype *rfts,
-			      int len)
-{
-	struct rftype *rft;
-	int ret;
-
-	lockdep_assert_held(&rdtgroup_mutex);
-
-	for (rft = rfts; rft < rfts + len; rft++) {
-		ret = rdtgroup_add_file(kn, rft);
-		if (ret)
-			goto error;
-	}
-
-	return 0;
-error:
-	pr_warn("Failed to add %s, err=%d\n", rft->name, ret);
-	while (--rft >= rfts)
-		kernfs_remove_by_name(kn, rft->name);
-	return ret;
-}
-
 static int rdtgroup_seqfile_show(struct seq_file *m, void *arg)
 {
 	struct kernfs_open_file *of = m->private;
@@ -174,6 +160,11 @@ static struct kernfs_ops rdtgroup_kf_single_ops = {
 	.seq_show		= rdtgroup_seqfile_show,
 };
 
+static struct kernfs_ops kf_mondata_ops = {
+	.atomic_write_len	= PAGE_SIZE,
+	.seq_show		= rdtgroup_mondata_show,
+};
+
 static bool is_cpu_list(struct kernfs_open_file *of)
 {
 	struct rftype *rft = of->kn->priv;
@@ -203,13 +194,18 @@ static int rdtgroup_cpus_show(struct kernfs_open_file *of,
 /*
  * This is safe against intel_rdt_sched_in() called from __switch_to()
  * because __switch_to() is executed with interrupts disabled. A local call
- * from rdt_update_closid() is proteced against __switch_to() because
+ * from update_closid_rmid() is proteced against __switch_to() because
  * preemption is disabled.
  */
-static void rdt_update_cpu_closid(void *closid)
+static void update_cpu_closid_rmid(void *info)
 {
-	if (closid)
-		this_cpu_write(cpu_closid, *(int *)closid);
+	struct rdtgroup *r = info;
+
+	if (r) {
+		this_cpu_write(pqr_state.default_closid, r->closid);
+		this_cpu_write(pqr_state.default_rmid, r->mon.rmid);
+	}
+
 	/*
 	 * We cannot unconditionally write the MSR because the current
 	 * executing task might have its own closid selected. Just reuse
@@ -221,28 +217,128 @@ static void rdt_update_cpu_closid(void *closid)
 /*
  * Update the PGR_ASSOC MSR on all cpus in @cpu_mask,
  *
- * Per task closids must have been set up before calling this function.
- *
- * The per cpu closids are updated with the smp function call, when @closid
- * is not NULL. If @closid is NULL then all affected percpu closids must
- * have been set up before calling this function.
+ * Per task closids/rmids must have been set up before calling this function.
  */
 static void
-rdt_update_closid(const struct cpumask *cpu_mask, int *closid)
+update_closid_rmid(const struct cpumask *cpu_mask, struct rdtgroup *r)
 {
 	int cpu = get_cpu();
 
 	if (cpumask_test_cpu(cpu, cpu_mask))
-		rdt_update_cpu_closid(closid);
-	smp_call_function_many(cpu_mask, rdt_update_cpu_closid, closid, 1);
+		update_cpu_closid_rmid(r);
+	smp_call_function_many(cpu_mask, update_cpu_closid_rmid, r, 1);
 	put_cpu();
 }
 
+static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
+			  cpumask_var_t tmpmask)
+{
+	struct rdtgroup *prgrp = rdtgrp->mon.parent, *crgrp;
+	struct list_head *head;
+
+	/* Check whether cpus belong to parent ctrl group */
+	cpumask_andnot(tmpmask, newmask, &prgrp->cpu_mask);
+	if (cpumask_weight(tmpmask))
+		return -EINVAL;
+
+	/* Check whether cpus are dropped from this group */
+	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
+	if (cpumask_weight(tmpmask)) {
+		/* Give any dropped cpus to parent rdtgroup */
+		cpumask_or(&prgrp->cpu_mask, &prgrp->cpu_mask, tmpmask);
+		update_closid_rmid(tmpmask, prgrp);
+	}
+
+	/*
+	 * If we added cpus, remove them from previous group that owned them
+	 * and update per-cpu rmid
+	 */
+	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
+	if (cpumask_weight(tmpmask)) {
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+			if (crgrp == rdtgrp)
+				continue;
+			cpumask_andnot(&crgrp->cpu_mask, &crgrp->cpu_mask,
+				       tmpmask);
+		}
+		update_closid_rmid(tmpmask, rdtgrp);
+	}
+
+	/* Done pushing/pulling - update this group with new mask */
+	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+
+	return 0;
+}
+
+static void cpumask_rdtgrp_clear(struct rdtgroup *r, struct cpumask *m)
+{
+	struct rdtgroup *crgrp;
+
+	cpumask_andnot(&r->cpu_mask, &r->cpu_mask, m);
+	/* update the child mon group masks as well*/
+	list_for_each_entry(crgrp, &r->mon.crdtgrp_list, mon.crdtgrp_list)
+		cpumask_and(&crgrp->cpu_mask, &r->cpu_mask, &crgrp->cpu_mask);
+}
+
+static int cpus_ctrl_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
+			   cpumask_var_t tmpmask, cpumask_var_t tmpmask1)
+{
+	struct rdtgroup *r, *crgrp;
+	struct list_head *head;
+
+	/* Check whether cpus are dropped from this group */
+	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
+	if (cpumask_weight(tmpmask)) {
+		/* Can't drop from default group */
+		if (rdtgrp == &rdtgroup_default)
+			return -EINVAL;
+
+		/* Give any dropped cpus to rdtgroup_default */
+		cpumask_or(&rdtgroup_default.cpu_mask,
+			   &rdtgroup_default.cpu_mask, tmpmask);
+		update_closid_rmid(tmpmask, &rdtgroup_default);
+	}
+
+	/*
+	 * If we added cpus, remove them from previous group and
+	 * the prev group's child groups that owned them
+	 * and update per-cpu closid/rmid.
+	 */
+	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
+	if (cpumask_weight(tmpmask)) {
+		list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) {
+			if (r == rdtgrp)
+				continue;
+			cpumask_and(tmpmask1, &r->cpu_mask, tmpmask);
+			if (cpumask_weight(tmpmask1))
+				cpumask_rdtgrp_clear(r, tmpmask1);
+		}
+		update_closid_rmid(tmpmask, rdtgrp);
+	}
+
+	/* Done pushing/pulling - update this group with new mask */
+	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+
+	/*
+	 * Clear child mon group masks since there is a new parent mask
+	 * now and update the rmid for the cpus the child lost.
+	 */
+	head = &rdtgrp->mon.crdtgrp_list;
+	list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+		cpumask_and(tmpmask, &rdtgrp->cpu_mask, &crgrp->cpu_mask);
+		update_closid_rmid(tmpmask, rdtgrp);
+		cpumask_clear(&crgrp->cpu_mask);
+	}
+
+	return 0;
+}
+
 static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of,
 				   char *buf, size_t nbytes, loff_t off)
 {
-	cpumask_var_t tmpmask, newmask;
-	struct rdtgroup *rdtgrp, *r;
+	cpumask_var_t tmpmask, newmask, tmpmask1;
+	struct rdtgroup *rdtgrp;
 	int ret;
 
 	if (!buf)
@@ -254,6 +350,11 @@ static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of,
 		free_cpumask_var(tmpmask);
 		return -ENOMEM;
 	}
+	if (!zalloc_cpumask_var(&tmpmask1, GFP_KERNEL)) {
+		free_cpumask_var(tmpmask);
+		free_cpumask_var(newmask);
+		return -ENOMEM;
+	}
 
 	rdtgrp = rdtgroup_kn_lock_live(of->kn);
 	if (!rdtgrp) {
@@ -276,41 +377,18 @@ static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of,
 		goto unlock;
 	}
 
-	/* Check whether cpus are dropped from this group */
-	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
-	if (cpumask_weight(tmpmask)) {
-		/* Can't drop from default group */
-		if (rdtgrp == &rdtgroup_default) {
-			ret = -EINVAL;
-			goto unlock;
-		}
-		/* Give any dropped cpus to rdtgroup_default */
-		cpumask_or(&rdtgroup_default.cpu_mask,
-			   &rdtgroup_default.cpu_mask, tmpmask);
-		rdt_update_closid(tmpmask, &rdtgroup_default.closid);
-	}
-
-	/*
-	 * If we added cpus, remove them from previous group that owned them
-	 * and update per-cpu closid
-	 */
-	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
-	if (cpumask_weight(tmpmask)) {
-		list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) {
-			if (r == rdtgrp)
-				continue;
-			cpumask_andnot(&r->cpu_mask, &r->cpu_mask, tmpmask);
-		}
-		rdt_update_closid(tmpmask, &rdtgrp->closid);
-	}
-
-	/* Done pushing/pulling - update this group with new mask */
-	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+	if (rdtgrp->type == RDTCTRL_GROUP)
+		ret = cpus_ctrl_write(rdtgrp, newmask, tmpmask, tmpmask1);
+	else if (rdtgrp->type == RDTMON_GROUP)
+		ret = cpus_mon_write(rdtgrp, newmask, tmpmask);
+	else
+		ret = -EINVAL;
 
 unlock:
 	rdtgroup_kn_unlock(of->kn);
 	free_cpumask_var(tmpmask);
 	free_cpumask_var(newmask);
+	free_cpumask_var(tmpmask1);
 
 	return ret ?: nbytes;
 }
@@ -336,6 +414,7 @@ static void move_myself(struct callback_head *head)
 	if (atomic_dec_and_test(&rdtgrp->waitcount) &&
 	    (rdtgrp->flags & RDT_DELETED)) {
 		current->closid = 0;
+		current->rmid = 0;
 		kfree(rdtgrp);
 	}
 
@@ -374,7 +453,20 @@ static int __rdtgroup_move_task(struct task_struct *tsk,
 		atomic_dec(&rdtgrp->waitcount);
 		kfree(callback);
 	} else {
-		tsk->closid = rdtgrp->closid;
+		/*
+		 * For ctrl_mon groups move both closid and rmid.
+		 * For monitor groups, can move the tasks only from
+		 * their parent CTRL group.
+		 */
+		if (rdtgrp->type == RDTCTRL_GROUP) {
+			tsk->closid = rdtgrp->closid;
+			tsk->rmid = rdtgrp->mon.rmid;
+		} else if (rdtgrp->type == RDTMON_GROUP) {
+			if (rdtgrp->mon.parent->closid == tsk->closid)
+				tsk->rmid = rdtgrp->mon.rmid;
+			else
+				ret = -EINVAL;
+		}
 	}
 	return ret;
 }
@@ -454,7 +546,8 @@ static void show_rdt_tasks(struct rdtgroup *r, struct seq_file *s)
 
 	rcu_read_lock();
 	for_each_process_thread(p, t) {
-		if (t->closid == r->closid)
+		if ((r->type == RDTCTRL_GROUP && t->closid == r->closid) ||
+		    (r->type == RDTMON_GROUP && t->rmid == r->mon.rmid))
 			seq_printf(s, "%d\n", t->pid);
 	}
 	rcu_read_unlock();
@@ -476,39 +569,6 @@ static int rdtgroup_tasks_show(struct kernfs_open_file *of,
 	return ret;
 }
 
-/* Files in each rdtgroup */
-static struct rftype rdtgroup_base_files[] = {
-	{
-		.name		= "cpus",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_cpus_write,
-		.seq_show	= rdtgroup_cpus_show,
-	},
-	{
-		.name		= "cpus_list",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_cpus_write,
-		.seq_show	= rdtgroup_cpus_show,
-		.flags		= RFTYPE_FLAGS_CPUS_LIST,
-	},
-	{
-		.name		= "tasks",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_tasks_write,
-		.seq_show	= rdtgroup_tasks_show,
-	},
-	{
-		.name		= "schemata",
-		.mode		= 0644,
-		.kf_ops		= &rdtgroup_kf_single_ops,
-		.write		= rdtgroup_schemata_write,
-		.seq_show	= rdtgroup_schemata_show,
-	},
-};
-
 static int rdt_num_closids_show(struct kernfs_open_file *of,
 				struct seq_file *seq, void *v)
 {
@@ -536,6 +596,15 @@ static int rdt_min_cbm_bits_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int rdt_shareable_bits_show(struct kernfs_open_file *of,
+				   struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%x\n", r->cache.shareable_bits);
+	return 0;
+}
+
 static int rdt_min_bw_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
@@ -545,6 +614,28 @@ static int rdt_min_bw_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int rdt_num_rmids_show(struct kernfs_open_file *of,
+			      struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%d\n", r->num_rmid);
+
+	return 0;
+}
+
+static int rdt_mon_features_show(struct kernfs_open_file *of,
+				 struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	struct mon_evt *mevt;
+
+	list_for_each_entry(mevt, &r->evt_list, list)
+		seq_printf(seq, "%s\n", mevt->name);
+
+	return 0;
+}
+
 static int rdt_bw_gran_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
@@ -563,74 +654,200 @@ static int rdt_delay_linear_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int max_threshold_occ_show(struct kernfs_open_file *of,
+				  struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%u\n", intel_cqm_threshold * r->mon_scale);
+
+	return 0;
+}
+
+static ssize_t max_threshold_occ_write(struct kernfs_open_file *of,
+				       char *buf, size_t nbytes, loff_t off)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	unsigned int bytes;
+	int ret;
+
+	ret = kstrtouint(buf, 0, &bytes);
+	if (ret)
+		return ret;
+
+	if (bytes > (boot_cpu_data.x86_cache_size * 1024))
+		return -EINVAL;
+
+	intel_cqm_threshold = bytes / r->mon_scale;
+
+	return nbytes;
+}
+
 /* rdtgroup information files for one cache resource. */
-static struct rftype res_cache_info_files[] = {
+static struct rftype res_common_files[] = {
 	{
 		.name		= "num_closids",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_num_closids_show,
+		.fflags		= RF_CTRL_INFO,
+	},
+	{
+		.name		= "mon_features",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_mon_features_show,
+		.fflags		= RF_MON_INFO,
+	},
+	{
+		.name		= "num_rmids",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_num_rmids_show,
+		.fflags		= RF_MON_INFO,
 	},
 	{
 		.name		= "cbm_mask",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_default_ctrl_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
 	},
 	{
 		.name		= "min_cbm_bits",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_min_cbm_bits_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
 	},
-};
-
-/* rdtgroup information files for memory bandwidth. */
-static struct rftype res_mba_info_files[] = {
 	{
-		.name		= "num_closids",
+		.name		= "shareable_bits",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
-		.seq_show	= rdt_num_closids_show,
+		.seq_show	= rdt_shareable_bits_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
 	},
 	{
 		.name		= "min_bandwidth",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_min_bw_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
 	},
 	{
 		.name		= "bandwidth_gran",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_bw_gran_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
 	},
 	{
 		.name		= "delay_linear",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdt_delay_linear_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
+	},
+	{
+		.name		= "max_threshold_occupancy",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= max_threshold_occ_write,
+		.seq_show	= max_threshold_occ_show,
+		.fflags		= RF_MON_INFO | RFTYPE_RES_CACHE,
+	},
+	{
+		.name		= "cpus",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_cpus_write,
+		.seq_show	= rdtgroup_cpus_show,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "cpus_list",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_cpus_write,
+		.seq_show	= rdtgroup_cpus_show,
+		.flags		= RFTYPE_FLAGS_CPUS_LIST,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "tasks",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_tasks_write,
+		.seq_show	= rdtgroup_tasks_show,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "schemata",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_schemata_write,
+		.seq_show	= rdtgroup_schemata_show,
+		.fflags		= RF_CTRL_BASE,
 	},
 };
 
-void rdt_get_mba_infofile(struct rdt_resource *r)
+static int rdtgroup_add_files(struct kernfs_node *kn, unsigned long fflags)
 {
-	r->info_files = res_mba_info_files;
-	r->nr_info_files = ARRAY_SIZE(res_mba_info_files);
+	struct rftype *rfts, *rft;
+	int ret, len;
+
+	rfts = res_common_files;
+	len = ARRAY_SIZE(res_common_files);
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	for (rft = rfts; rft < rfts + len; rft++) {
+		if ((fflags & rft->fflags) == rft->fflags) {
+			ret = rdtgroup_add_file(kn, rft);
+			if (ret)
+				goto error;
+		}
+	}
+
+	return 0;
+error:
+	pr_warn("Failed to add %s, err=%d\n", rft->name, ret);
+	while (--rft >= rfts) {
+		if ((fflags & rft->fflags) == rft->fflags)
+			kernfs_remove_by_name(kn, rft->name);
+	}
+	return ret;
 }
 
-void rdt_get_cache_infofile(struct rdt_resource *r)
+static int rdtgroup_mkdir_info_resdir(struct rdt_resource *r, char *name,
+				      unsigned long fflags)
 {
-	r->info_files = res_cache_info_files;
-	r->nr_info_files = ARRAY_SIZE(res_cache_info_files);
+	struct kernfs_node *kn_subdir;
+	int ret;
+
+	kn_subdir = kernfs_create_dir(kn_info, name,
+				      kn_info->mode, r);
+	if (IS_ERR(kn_subdir))
+		return PTR_ERR(kn_subdir);
+
+	kernfs_get(kn_subdir);
+	ret = rdtgroup_kn_set_ugid(kn_subdir);
+	if (ret)
+		return ret;
+
+	ret = rdtgroup_add_files(kn_subdir, fflags);
+	if (!ret)
+		kernfs_activate(kn_subdir);
+
+	return ret;
 }
 
 static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
 {
-	struct kernfs_node *kn_subdir;
-	struct rftype *res_info_files;
 	struct rdt_resource *r;
-	int ret, len;
+	unsigned long fflags;
+	char name[32];
+	int ret;
 
 	/* create the directory */
 	kn_info = kernfs_create_dir(parent_kn, "info", parent_kn->mode, NULL);
@@ -638,25 +855,19 @@ static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
 		return PTR_ERR(kn_info);
 	kernfs_get(kn_info);
 
-	for_each_enabled_rdt_resource(r) {
-		kn_subdir = kernfs_create_dir(kn_info, r->name,
-					      kn_info->mode, r);
-		if (IS_ERR(kn_subdir)) {
-			ret = PTR_ERR(kn_subdir);
-			goto out_destroy;
-		}
-		kernfs_get(kn_subdir);
-		ret = rdtgroup_kn_set_ugid(kn_subdir);
+	for_each_alloc_enabled_rdt_resource(r) {
+		fflags =  r->fflags | RF_CTRL_INFO;
+		ret = rdtgroup_mkdir_info_resdir(r, r->name, fflags);
 		if (ret)
 			goto out_destroy;
+	}
 
-		res_info_files = r->info_files;
-		len = r->nr_info_files;
-
-		ret = rdtgroup_add_files(kn_subdir, res_info_files, len);
+	for_each_mon_enabled_rdt_resource(r) {
+		fflags =  r->fflags | RF_MON_INFO;
+		sprintf(name, "%s_MON", r->name);
+		ret = rdtgroup_mkdir_info_resdir(r, name, fflags);
 		if (ret)
 			goto out_destroy;
-		kernfs_activate(kn_subdir);
 	}
 
 	/*
@@ -678,6 +889,39 @@ out_destroy:
 	return ret;
 }
 
+static int
+mongroup_create_dir(struct kernfs_node *parent_kn, struct rdtgroup *prgrp,
+		    char *name, struct kernfs_node **dest_kn)
+{
+	struct kernfs_node *kn;
+	int ret;
+
+	/* create the directory */
+	kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	if (dest_kn)
+		*dest_kn = kn;
+
+	/*
+	 * This extra ref will be put in kernfs_remove() and guarantees
+	 * that @rdtgrp->kn is always accessible.
+	 */
+	kernfs_get(kn);
+
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret)
+		goto out_destroy;
+
+	kernfs_activate(kn);
+
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
 static void l3_qos_cfg_update(void *arg)
 {
 	bool *enable = arg;
@@ -718,14 +962,15 @@ static int cdp_enable(void)
 	struct rdt_resource *r_l3 = &rdt_resources_all[RDT_RESOURCE_L3];
 	int ret;
 
-	if (!r_l3->capable || !r_l3data->capable || !r_l3code->capable)
+	if (!r_l3->alloc_capable || !r_l3data->alloc_capable ||
+	    !r_l3code->alloc_capable)
 		return -EINVAL;
 
 	ret = set_l3_qos_cfg(r_l3, true);
 	if (!ret) {
-		r_l3->enabled = false;
-		r_l3data->enabled = true;
-		r_l3code->enabled = true;
+		r_l3->alloc_enabled = false;
+		r_l3data->alloc_enabled = true;
+		r_l3code->alloc_enabled = true;
 	}
 	return ret;
 }
@@ -734,11 +979,11 @@ static void cdp_disable(void)
 {
 	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3];
 
-	r->enabled = r->capable;
+	r->alloc_enabled = r->alloc_capable;
 
-	if (rdt_resources_all[RDT_RESOURCE_L3DATA].enabled) {
-		rdt_resources_all[RDT_RESOURCE_L3DATA].enabled = false;
-		rdt_resources_all[RDT_RESOURCE_L3CODE].enabled = false;
+	if (rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled) {
+		rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled = false;
+		rdt_resources_all[RDT_RESOURCE_L3CODE].alloc_enabled = false;
 		set_l3_qos_cfg(r, false);
 	}
 }
@@ -823,10 +1068,16 @@ void rdtgroup_kn_unlock(struct kernfs_node *kn)
 	}
 }
 
+static int mkdir_mondata_all(struct kernfs_node *parent_kn,
+			     struct rdtgroup *prgrp,
+			     struct kernfs_node **mon_data_kn);
+
 static struct dentry *rdt_mount(struct file_system_type *fs_type,
 				int flags, const char *unused_dev_name,
 				void *data)
 {
+	struct rdt_domain *dom;
+	struct rdt_resource *r;
 	struct dentry *dentry;
 	int ret;
 
@@ -853,15 +1104,54 @@ static struct dentry *rdt_mount(struct file_system_type *fs_type,
 		goto out_cdp;
 	}
 
+	if (rdt_mon_capable) {
+		ret = mongroup_create_dir(rdtgroup_default.kn,
+					  NULL, "mon_groups",
+					  &kn_mongrp);
+		if (ret) {
+			dentry = ERR_PTR(ret);
+			goto out_info;
+		}
+		kernfs_get(kn_mongrp);
+
+		ret = mkdir_mondata_all(rdtgroup_default.kn,
+					&rdtgroup_default, &kn_mondata);
+		if (ret) {
+			dentry = ERR_PTR(ret);
+			goto out_mongrp;
+		}
+		kernfs_get(kn_mondata);
+		rdtgroup_default.mon.mon_data_kn = kn_mondata;
+	}
+
 	dentry = kernfs_mount(fs_type, flags, rdt_root,
 			      RDTGROUP_SUPER_MAGIC, NULL);
 	if (IS_ERR(dentry))
-		goto out_destroy;
+		goto out_mondata;
+
+	if (rdt_alloc_capable)
+		static_branch_enable(&rdt_alloc_enable_key);
+	if (rdt_mon_capable)
+		static_branch_enable(&rdt_mon_enable_key);
+
+	if (rdt_alloc_capable || rdt_mon_capable)
+		static_branch_enable(&rdt_enable_key);
+
+	if (is_mbm_enabled()) {
+		r = &rdt_resources_all[RDT_RESOURCE_L3];
+		list_for_each_entry(dom, &r->domains, list)
+			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL);
+	}
 
-	static_branch_enable(&rdt_enable_key);
 	goto out;
 
-out_destroy:
+out_mondata:
+	if (rdt_mon_capable)
+		kernfs_remove(kn_mondata);
+out_mongrp:
+	if (rdt_mon_capable)
+		kernfs_remove(kn_mongrp);
+out_info:
 	kernfs_remove(kn_info);
 out_cdp:
 	cdp_disable();
@@ -909,6 +1199,18 @@ static int reset_all_ctrls(struct rdt_resource *r)
 	return 0;
 }
 
+static bool is_closid_match(struct task_struct *t, struct rdtgroup *r)
+{
+	return (rdt_alloc_capable &&
+		(r->type == RDTCTRL_GROUP) && (t->closid == r->closid));
+}
+
+static bool is_rmid_match(struct task_struct *t, struct rdtgroup *r)
+{
+	return (rdt_mon_capable &&
+		(r->type == RDTMON_GROUP) && (t->rmid == r->mon.rmid));
+}
+
 /*
  * Move tasks from one to the other group. If @from is NULL, then all tasks
  * in the systems are moved unconditionally (used for teardown).
@@ -924,8 +1226,11 @@ static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
 
 	read_lock(&tasklist_lock);
 	for_each_process_thread(p, t) {
-		if (!from || t->closid == from->closid) {
+		if (!from || is_closid_match(t, from) ||
+		    is_rmid_match(t, from)) {
 			t->closid = to->closid;
+			t->rmid = to->mon.rmid;
+
 #ifdef CONFIG_SMP
 			/*
 			 * This is safe on x86 w/o barriers as the ordering
@@ -944,6 +1249,19 @@ static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
 	read_unlock(&tasklist_lock);
 }
 
+static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
+{
+	struct rdtgroup *sentry, *stmp;
+	struct list_head *head;
+
+	head = &rdtgrp->mon.crdtgrp_list;
+	list_for_each_entry_safe(sentry, stmp, head, mon.crdtgrp_list) {
+		free_rmid(sentry->mon.rmid);
+		list_del(&sentry->mon.crdtgrp_list);
+		kfree(sentry);
+	}
+}
+
 /*
  * Forcibly remove all of subdirectories under root.
  */
@@ -955,6 +1273,9 @@ static void rmdir_all_sub(void)
 	rdt_move_group_tasks(NULL, &rdtgroup_default, NULL);
 
 	list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) {
+		/* Free any child rmids */
+		free_all_child_rdtgrp(rdtgrp);
+
 		/* Remove each rdtgroup other than root */
 		if (rdtgrp == &rdtgroup_default)
 			continue;
@@ -967,16 +1288,20 @@ static void rmdir_all_sub(void)
 		cpumask_or(&rdtgroup_default.cpu_mask,
 			   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
 
+		free_rmid(rdtgrp->mon.rmid);
+
 		kernfs_remove(rdtgrp->kn);
 		list_del(&rdtgrp->rdtgroup_list);
 		kfree(rdtgrp);
 	}
 	/* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */
 	get_online_cpus();
-	rdt_update_closid(cpu_online_mask, &rdtgroup_default.closid);
+	update_closid_rmid(cpu_online_mask, &rdtgroup_default);
 	put_online_cpus();
 
 	kernfs_remove(kn_info);
+	kernfs_remove(kn_mongrp);
+	kernfs_remove(kn_mondata);
 }
 
 static void rdt_kill_sb(struct super_block *sb)
@@ -986,10 +1311,12 @@ static void rdt_kill_sb(struct super_block *sb)
 	mutex_lock(&rdtgroup_mutex);
 
 	/*Put everything back to default values. */
-	for_each_enabled_rdt_resource(r)
+	for_each_alloc_enabled_rdt_resource(r)
 		reset_all_ctrls(r);
 	cdp_disable();
 	rmdir_all_sub();
+	static_branch_disable(&rdt_alloc_enable_key);
+	static_branch_disable(&rdt_mon_enable_key);
 	static_branch_disable(&rdt_enable_key);
 	kernfs_kill_sb(sb);
 	mutex_unlock(&rdtgroup_mutex);
@@ -1001,46 +1328,223 @@ static struct file_system_type rdt_fs_type = {
 	.kill_sb = rdt_kill_sb,
 };
 
-static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
-			  umode_t mode)
+static int mon_addfile(struct kernfs_node *parent_kn, const char *name,
+		       void *priv)
 {
-	struct rdtgroup *parent, *rdtgrp;
 	struct kernfs_node *kn;
-	int ret, closid;
+	int ret = 0;
 
-	/* Only allow mkdir in the root directory */
-	if (parent_kn != rdtgroup_default.kn)
-		return -EPERM;
+	kn = __kernfs_create_file(parent_kn, name, 0444, 0,
+				  &kf_mondata_ops, priv, NULL, NULL);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
 
-	/* Do not accept '\n' to avoid unparsable situation. */
-	if (strchr(name, '\n'))
-		return -EINVAL;
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret) {
+		kernfs_remove(kn);
+		return ret;
+	}
 
-	parent = rdtgroup_kn_lock_live(parent_kn);
-	if (!parent) {
-		ret = -ENODEV;
-		goto out_unlock;
+	return ret;
+}
+
+/*
+ * Remove all subdirectories of mon_data of ctrl_mon groups
+ * and monitor groups with given domain id.
+ */
+void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r, unsigned int dom_id)
+{
+	struct rdtgroup *prgrp, *crgrp;
+	char name[32];
+
+	if (!r->mon_enabled)
+		return;
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		sprintf(name, "mon_%s_%02d", r->name, dom_id);
+		kernfs_remove_by_name(prgrp->mon.mon_data_kn, name);
+
+		list_for_each_entry(crgrp, &prgrp->mon.crdtgrp_list, mon.crdtgrp_list)
+			kernfs_remove_by_name(crgrp->mon.mon_data_kn, name);
 	}
+}
 
-	ret = closid_alloc();
-	if (ret < 0)
+static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
+				struct rdt_domain *d,
+				struct rdt_resource *r, struct rdtgroup *prgrp)
+{
+	union mon_data_bits priv;
+	struct kernfs_node *kn;
+	struct mon_evt *mevt;
+	struct rmid_read rr;
+	char name[32];
+	int ret;
+
+	sprintf(name, "mon_%s_%02d", r->name, d->id);
+	/* create the directory */
+	kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	/*
+	 * This extra ref will be put in kernfs_remove() and guarantees
+	 * that kn is always accessible.
+	 */
+	kernfs_get(kn);
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret)
+		goto out_destroy;
+
+	if (WARN_ON(list_empty(&r->evt_list))) {
+		ret = -EPERM;
+		goto out_destroy;
+	}
+
+	priv.u.rid = r->rid;
+	priv.u.domid = d->id;
+	list_for_each_entry(mevt, &r->evt_list, list) {
+		priv.u.evtid = mevt->evtid;
+		ret = mon_addfile(kn, mevt->name, priv.priv);
+		if (ret)
+			goto out_destroy;
+
+		if (is_mbm_event(mevt->evtid))
+			mon_event_read(&rr, d, prgrp, mevt->evtid, true);
+	}
+	kernfs_activate(kn);
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
+
+/*
+ * Add all subdirectories of mon_data for "ctrl_mon" groups
+ * and "monitor" groups with given domain id.
+ */
+void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
+				    struct rdt_domain *d)
+{
+	struct kernfs_node *parent_kn;
+	struct rdtgroup *prgrp, *crgrp;
+	struct list_head *head;
+
+	if (!r->mon_enabled)
+		return;
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		parent_kn = prgrp->mon.mon_data_kn;
+		mkdir_mondata_subdir(parent_kn, d, r, prgrp);
+
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+			parent_kn = crgrp->mon.mon_data_kn;
+			mkdir_mondata_subdir(parent_kn, d, r, crgrp);
+		}
+	}
+}
+
+static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn,
+				       struct rdt_resource *r,
+				       struct rdtgroup *prgrp)
+{
+	struct rdt_domain *dom;
+	int ret;
+
+	list_for_each_entry(dom, &r->domains, list) {
+		ret = mkdir_mondata_subdir(parent_kn, dom, r, prgrp);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/*
+ * This creates a directory mon_data which contains the monitored data.
+ *
+ * mon_data has one directory for each domain whic are named
+ * in the format mon_<domain_name>_<domain_id>. For ex: A mon_data
+ * with L3 domain looks as below:
+ * ./mon_data:
+ * mon_L3_00
+ * mon_L3_01
+ * mon_L3_02
+ * ...
+ *
+ * Each domain directory has one file per event:
+ * ./mon_L3_00/:
+ * llc_occupancy
+ *
+ */
+static int mkdir_mondata_all(struct kernfs_node *parent_kn,
+			     struct rdtgroup *prgrp,
+			     struct kernfs_node **dest_kn)
+{
+	struct rdt_resource *r;
+	struct kernfs_node *kn;
+	int ret;
+
+	/*
+	 * Create the mon_data directory first.
+	 */
+	ret = mongroup_create_dir(parent_kn, NULL, "mon_data", &kn);
+	if (ret)
+		return ret;
+
+	if (dest_kn)
+		*dest_kn = kn;
+
+	/*
+	 * Create the subdirectories for each domain. Note that all events
+	 * in a domain like L3 are grouped into a resource whose domain is L3
+	 */
+	for_each_mon_enabled_rdt_resource(r) {
+		ret = mkdir_mondata_subdir_alldom(kn, r, prgrp);
+		if (ret)
+			goto out_destroy;
+	}
+
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
+
+static int mkdir_rdt_prepare(struct kernfs_node *parent_kn,
+			     struct kernfs_node *prgrp_kn,
+			     const char *name, umode_t mode,
+			     enum rdt_group_type rtype, struct rdtgroup **r)
+{
+	struct rdtgroup *prdtgrp, *rdtgrp;
+	struct kernfs_node *kn;
+	uint files = 0;
+	int ret;
+
+	prdtgrp = rdtgroup_kn_lock_live(prgrp_kn);
+	if (!prdtgrp) {
+		ret = -ENODEV;
 		goto out_unlock;
-	closid = ret;
+	}
 
 	/* allocate the rdtgroup. */
 	rdtgrp = kzalloc(sizeof(*rdtgrp), GFP_KERNEL);
 	if (!rdtgrp) {
 		ret = -ENOSPC;
-		goto out_closid_free;
+		goto out_unlock;
 	}
-	rdtgrp->closid = closid;
-	list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups);
+	*r = rdtgrp;
+	rdtgrp->mon.parent = prdtgrp;
+	rdtgrp->type = rtype;
+	INIT_LIST_HEAD(&rdtgrp->mon.crdtgrp_list);
 
 	/* kernfs creates the directory for rdtgrp */
-	kn = kernfs_create_dir(parent->kn, name, mode, rdtgrp);
+	kn = kernfs_create_dir(parent_kn, name, mode, rdtgrp);
 	if (IS_ERR(kn)) {
 		ret = PTR_ERR(kn);
-		goto out_cancel_ref;
+		goto out_free_rgrp;
 	}
 	rdtgrp->kn = kn;
 
@@ -1056,43 +1560,211 @@ static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
 	if (ret)
 		goto out_destroy;
 
-	ret = rdtgroup_add_files(kn, rdtgroup_base_files,
-				 ARRAY_SIZE(rdtgroup_base_files));
+	files = RFTYPE_BASE | RFTYPE_CTRL;
+	files = RFTYPE_BASE | BIT(RF_CTRLSHIFT + rtype);
+	ret = rdtgroup_add_files(kn, files);
 	if (ret)
 		goto out_destroy;
 
+	if (rdt_mon_capable) {
+		ret = alloc_rmid();
+		if (ret < 0)
+			goto out_destroy;
+		rdtgrp->mon.rmid = ret;
+
+		ret = mkdir_mondata_all(kn, rdtgrp, &rdtgrp->mon.mon_data_kn);
+		if (ret)
+			goto out_idfree;
+	}
 	kernfs_activate(kn);
 
-	ret = 0;
-	goto out_unlock;
+	/*
+	 * The caller unlocks the prgrp_kn upon success.
+	 */
+	return 0;
 
+out_idfree:
+	free_rmid(rdtgrp->mon.rmid);
 out_destroy:
 	kernfs_remove(rdtgrp->kn);
-out_cancel_ref:
-	list_del(&rdtgrp->rdtgroup_list);
+out_free_rgrp:
 	kfree(rdtgrp);
-out_closid_free:
-	closid_free(closid);
 out_unlock:
-	rdtgroup_kn_unlock(parent_kn);
+	rdtgroup_kn_unlock(prgrp_kn);
 	return ret;
 }
 
-static int rdtgroup_rmdir(struct kernfs_node *kn)
+static void mkdir_rdt_prepare_clean(struct rdtgroup *rgrp)
+{
+	kernfs_remove(rgrp->kn);
+	free_rmid(rgrp->mon.rmid);
+	kfree(rgrp);
+}
+
+/*
+ * Create a monitor group under "mon_groups" directory of a control
+ * and monitor group(ctrl_mon). This is a resource group
+ * to monitor a subset of tasks and cpus in its parent ctrl_mon group.
+ */
+static int rdtgroup_mkdir_mon(struct kernfs_node *parent_kn,
+			      struct kernfs_node *prgrp_kn,
+			      const char *name,
+			      umode_t mode)
+{
+	struct rdtgroup *rdtgrp, *prgrp;
+	int ret;
+
+	ret = mkdir_rdt_prepare(parent_kn, prgrp_kn, name, mode, RDTMON_GROUP,
+				&rdtgrp);
+	if (ret)
+		return ret;
+
+	prgrp = rdtgrp->mon.parent;
+	rdtgrp->closid = prgrp->closid;
+
+	/*
+	 * Add the rdtgrp to the list of rdtgrps the parent
+	 * ctrl_mon group has to track.
+	 */
+	list_add_tail(&rdtgrp->mon.crdtgrp_list, &prgrp->mon.crdtgrp_list);
+
+	rdtgroup_kn_unlock(prgrp_kn);
+	return ret;
+}
+
+/*
+ * These are rdtgroups created under the root directory. Can be used
+ * to allocate and monitor resources.
+ */
+static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn,
+				   struct kernfs_node *prgrp_kn,
+				   const char *name, umode_t mode)
 {
-	int ret, cpu, closid = rdtgroup_default.closid;
 	struct rdtgroup *rdtgrp;
-	cpumask_var_t tmpmask;
+	struct kernfs_node *kn;
+	u32 closid;
+	int ret;
 
-	if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL))
-		return -ENOMEM;
+	ret = mkdir_rdt_prepare(parent_kn, prgrp_kn, name, mode, RDTCTRL_GROUP,
+				&rdtgrp);
+	if (ret)
+		return ret;
 
-	rdtgrp = rdtgroup_kn_lock_live(kn);
-	if (!rdtgrp) {
-		ret = -EPERM;
-		goto out;
+	kn = rdtgrp->kn;
+	ret = closid_alloc();
+	if (ret < 0)
+		goto out_common_fail;
+	closid = ret;
+
+	rdtgrp->closid = closid;
+	list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups);
+
+	if (rdt_mon_capable) {
+		/*
+		 * Create an empty mon_groups directory to hold the subset
+		 * of tasks and cpus to monitor.
+		 */
+		ret = mongroup_create_dir(kn, NULL, "mon_groups", NULL);
+		if (ret)
+			goto out_id_free;
 	}
 
+	goto out_unlock;
+
+out_id_free:
+	closid_free(closid);
+	list_del(&rdtgrp->rdtgroup_list);
+out_common_fail:
+	mkdir_rdt_prepare_clean(rdtgrp);
+out_unlock:
+	rdtgroup_kn_unlock(prgrp_kn);
+	return ret;
+}
+
+/*
+ * We allow creating mon groups only with in a directory called "mon_groups"
+ * which is present in every ctrl_mon group. Check if this is a valid
+ * "mon_groups" directory.
+ *
+ * 1. The directory should be named "mon_groups".
+ * 2. The mon group itself should "not" be named "mon_groups".
+ *   This makes sure "mon_groups" directory always has a ctrl_mon group
+ *   as parent.
+ */
+static bool is_mon_groups(struct kernfs_node *kn, const char *name)
+{
+	return (!strcmp(kn->name, "mon_groups") &&
+		strcmp(name, "mon_groups"));
+}
+
+static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
+			  umode_t mode)
+{
+	/* Do not accept '\n' to avoid unparsable situation. */
+	if (strchr(name, '\n'))
+		return -EINVAL;
+
+	/*
+	 * If the parent directory is the root directory and RDT
+	 * allocation is supported, add a control and monitoring
+	 * subdirectory
+	 */
+	if (rdt_alloc_capable && parent_kn == rdtgroup_default.kn)
+		return rdtgroup_mkdir_ctrl_mon(parent_kn, parent_kn, name, mode);
+
+	/*
+	 * If RDT monitoring is supported and the parent directory is a valid
+	 * "mon_groups" directory, add a monitoring subdirectory.
+	 */
+	if (rdt_mon_capable && is_mon_groups(parent_kn, name))
+		return rdtgroup_mkdir_mon(parent_kn, parent_kn->parent, name, mode);
+
+	return -EPERM;
+}
+
+static int rdtgroup_rmdir_mon(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
+			      cpumask_var_t tmpmask)
+{
+	struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
+	int cpu;
+
+	/* Give any tasks back to the parent group */
+	rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask);
+
+	/* Update per cpu rmid of the moved CPUs first */
+	for_each_cpu(cpu, &rdtgrp->cpu_mask)
+		per_cpu(pqr_state.default_rmid, cpu) = prdtgrp->mon.rmid;
+	/*
+	 * Update the MSR on moved CPUs and CPUs which have moved
+	 * task running on them.
+	 */
+	cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
+	update_closid_rmid(tmpmask, NULL);
+
+	rdtgrp->flags = RDT_DELETED;
+	free_rmid(rdtgrp->mon.rmid);
+
+	/*
+	 * Remove the rdtgrp from the parent ctrl_mon group's list
+	 */
+	WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list));
+	list_del(&rdtgrp->mon.crdtgrp_list);
+
+	/*
+	 * one extra hold on this, will drop when we kfree(rdtgrp)
+	 * in rdtgroup_kn_unlock()
+	 */
+	kernfs_get(kn);
+	kernfs_remove(rdtgrp->kn);
+
+	return 0;
+}
+
+static int rdtgroup_rmdir_ctrl(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
+			       cpumask_var_t tmpmask)
+{
+	int cpu;
+
 	/* Give any tasks back to the default group */
 	rdt_move_group_tasks(rdtgrp, &rdtgroup_default, tmpmask);
 
@@ -1100,18 +1772,28 @@ static int rdtgroup_rmdir(struct kernfs_node *kn)
 	cpumask_or(&rdtgroup_default.cpu_mask,
 		   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
 
-	/* Update per cpu closid of the moved CPUs first */
-	for_each_cpu(cpu, &rdtgrp->cpu_mask)
-		per_cpu(cpu_closid, cpu) = closid;
+	/* Update per cpu closid and rmid of the moved CPUs first */
+	for_each_cpu(cpu, &rdtgrp->cpu_mask) {
+		per_cpu(pqr_state.default_closid, cpu) = rdtgroup_default.closid;
+		per_cpu(pqr_state.default_rmid, cpu) = rdtgroup_default.mon.rmid;
+	}
+
 	/*
 	 * Update the MSR on moved CPUs and CPUs which have moved
 	 * task running on them.
 	 */
 	cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
-	rdt_update_closid(tmpmask, NULL);
+	update_closid_rmid(tmpmask, NULL);
 
 	rdtgrp->flags = RDT_DELETED;
 	closid_free(rdtgrp->closid);
+	free_rmid(rdtgrp->mon.rmid);
+
+	/*
+	 * Free all the child monitor group rmids.
+	 */
+	free_all_child_rdtgrp(rdtgrp);
+
 	list_del(&rdtgrp->rdtgroup_list);
 
 	/*
@@ -1120,7 +1802,41 @@ static int rdtgroup_rmdir(struct kernfs_node *kn)
 	 */
 	kernfs_get(kn);
 	kernfs_remove(rdtgrp->kn);
-	ret = 0;
+
+	return 0;
+}
+
+static int rdtgroup_rmdir(struct kernfs_node *kn)
+{
+	struct kernfs_node *parent_kn = kn->parent;
+	struct rdtgroup *rdtgrp;
+	cpumask_var_t tmpmask;
+	int ret = 0;
+
+	if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL))
+		return -ENOMEM;
+
+	rdtgrp = rdtgroup_kn_lock_live(kn);
+	if (!rdtgrp) {
+		ret = -EPERM;
+		goto out;
+	}
+
+	/*
+	 * If the rdtgroup is a ctrl_mon group and parent directory
+	 * is the root directory, remove the ctrl_mon group.
+	 *
+	 * If the rdtgroup is a mon group and parent directory
+	 * is a valid "mon_groups" directory, remove the mon group.
+	 */
+	if (rdtgrp->type == RDTCTRL_GROUP && parent_kn == rdtgroup_default.kn)
+		ret = rdtgroup_rmdir_ctrl(kn, rdtgrp, tmpmask);
+	else if (rdtgrp->type == RDTMON_GROUP &&
+		 is_mon_groups(parent_kn, kn->name))
+		ret = rdtgroup_rmdir_mon(kn, rdtgrp, tmpmask);
+	else
+		ret = -EPERM;
+
 out:
 	rdtgroup_kn_unlock(kn);
 	free_cpumask_var(tmpmask);
@@ -1129,7 +1845,7 @@ out:
 
 static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
 {
-	if (rdt_resources_all[RDT_RESOURCE_L3DATA].enabled)
+	if (rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled)
 		seq_puts(seq, ",cdp");
 	return 0;
 }
@@ -1153,10 +1869,13 @@ static int __init rdtgroup_setup_root(void)
 	mutex_lock(&rdtgroup_mutex);
 
 	rdtgroup_default.closid = 0;
+	rdtgroup_default.mon.rmid = 0;
+	rdtgroup_default.type = RDTCTRL_GROUP;
+	INIT_LIST_HEAD(&rdtgroup_default.mon.crdtgrp_list);
+
 	list_add(&rdtgroup_default.rdtgroup_list, &rdt_all_groups);
 
-	ret = rdtgroup_add_files(rdt_root->kn, rdtgroup_base_files,
-				 ARRAY_SIZE(rdtgroup_base_files));
+	ret = rdtgroup_add_files(rdt_root->kn, RF_CTRL_BASE);
 	if (ret) {
 		kernfs_destroy_root(rdt_root);
 		goto out;