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Subject: [PATCH v3 5/7] x86/resctrl: Display the RMID and COSID for resctrl
 groups
From:   Babu Moger <babu.moger@amd.com>
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Date:   Thu, 2 Mar 2023 14:24:54 -0600
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When a user creates a control or monitor group, the CLOSID or RMID=0A=
are not visible to the user. These are architecturally defined entities.=0A=
There is no harm in displaying these in resctrl groups. Sometimes it=0A=
can help to debug the issues.=0A=
=0A=
Add CLOSID and RMID to the control/monitor groups display in resctrl=0A=
interface.=0A=
=0A=
$cat /sys/fs/resctrl/clos1/closid=0A=
1=0A=
$cat /sys/fs/resctrl/mon_groups/mon1/rmid=0A=
3=0A=
=0A=
Signed-off-by: Babu Moger <babu.moger@amd.com>=0A=
---=0A=
 Documentation/x86/resctrl.rst          |   17 ++++++++++++=0A=
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |   44 ++++++++++++++++++++++++++++=
++++=0A=
 2 files changed, 61 insertions(+)=0A=
=0A=
diff --git a/Documentation/x86/resctrl.rst b/Documentation/x86/resctrl.rst=
=0A=
index 25203f20002d..67eae74fe40c 100644=0A=
--- a/Documentation/x86/resctrl.rst=0A=
+++ b/Documentation/x86/resctrl.rst=0A=
@@ -321,6 +321,15 @@ All groups contain the following files:=0A=
 	Just like "cpus", only using ranges of CPUs instead of bitmasks.=0A=
 =0A=
 =0A=
+"rmid":=0A=
+	Available only with debug option.Reading this file shows the=0A=
+	Resource Monitoring ID (RMID) for monitoring the resource=0A=
+	utilization. Monitoring is performed by tagging each core (or=0A=
+	thread) or process via a RMID. Kernel assigns a new RMID when=0A=
+	a group is created depending on the available RMIDs. Multiple=0A=
+	cores (or threads) or processes can share a same RMID in a resctrl=0A=
+	domain.=0A=
+=0A=
 When control is enabled all CTRL_MON groups will also contain:=0A=
 =0A=
 "schemata":=0A=
@@ -342,6 +351,14 @@ When control is enabled all CTRL_MON groups will also =
contain:=0A=
 	file. On successful pseudo-locked region creation the mode will=0A=
 	automatically change to "pseudo-locked".=0A=
 =0A=
+"closid":=0A=
+	Available only with debug option. Reading this file shows the=0A=
+	Class of Service (CLOS) id which acts as a resource control tag=0A=
+	on which the resources can be throttled. Kernel assigns a new=0A=
+	CLOSID a control group is created depending on the available=0A=
+	CLOSIDs. Multiple cores(or threads) or processes can share a=0A=
+	same CLOSID in a resctrl domain.=0A=
+=0A=
 When monitoring is enabled all MON groups will also contain:=0A=
 =0A=
 "mon_data":=0A=
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/r=
esctrl/rdtgroup.c=0A=
index 1eb538965bd3..389d64b42704 100644=0A=
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c=0A=
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c=0A=
@@ -760,6 +760,38 @@ static int rdtgroup_tasks_show(struct kernfs_open_file=
 *of,=0A=
 	return ret;=0A=
 }=0A=
 =0A=
+static int rdtgroup_closid_show(struct kernfs_open_file *of,=0A=
+				struct seq_file *s, void *v)=0A=
+{=0A=
+	struct rdtgroup *rdtgrp;=0A=
+	int ret =3D 0;=0A=
+=0A=
+	rdtgrp =3D rdtgroup_kn_lock_live(of->kn);=0A=
+	if (rdtgrp)=0A=
+		seq_printf(s, "%u\n", rdtgrp->closid);=0A=
+	else=0A=
+		ret =3D -ENOENT;=0A=
+	rdtgroup_kn_unlock(of->kn);=0A=
+=0A=
+	return ret;=0A=
+}=0A=
+=0A=
+static int rdtgroup_rmid_show(struct kernfs_open_file *of,=0A=
+			      struct seq_file *s, void *v)=0A=
+{=0A=
+	struct rdtgroup *rdtgrp;=0A=
+	int ret =3D 0;=0A=
+=0A=
+	rdtgrp =3D rdtgroup_kn_lock_live(of->kn);=0A=
+	if (rdtgrp)=0A=
+		seq_printf(s, "%u\n", rdtgrp->mon.rmid);=0A=
+	else=0A=
+		ret =3D -ENOENT;=0A=
+	rdtgroup_kn_unlock(of->kn);=0A=
+=0A=
+	return ret;=0A=
+}=0A=
+=0A=
 #ifdef CONFIG_PROC_CPU_RESCTRL=0A=
 =0A=
 /*=0A=
@@ -1821,6 +1853,12 @@ static struct rftype res_common_files[] =3D {=0A=
 		.seq_show	=3D rdtgroup_tasks_show,=0A=
 		.fflags		=3D RFTYPE_BASE,=0A=
 	},=0A=
+	{=0A=
+		.name		=3D "rmid",=0A=
+		.mode		=3D 0444,=0A=
+		.kf_ops		=3D &rdtgroup_kf_single_ops,=0A=
+		.seq_show	=3D rdtgroup_rmid_show,=0A=
+	},=0A=
 	{=0A=
 		.name		=3D "schemata",=0A=
 		.mode		=3D 0644,=0A=
@@ -1844,6 +1882,12 @@ static struct rftype res_common_files[] =3D {=0A=
 		.seq_show	=3D rdtgroup_size_show,=0A=
 		.fflags		=3D RFTYPE_BASE_CTRL,=0A=
 	},=0A=
+	{=0A=
+		.name		=3D "closid",=0A=
+		.mode		=3D 0444,=0A=
+		.kf_ops		=3D &rdtgroup_kf_single_ops,=0A=
+		.seq_show	=3D rdtgroup_closid_show,=0A=
+	},=0A=
 =0A=
 };=0A=
 =0A=
=0A=