In x86, hardware uses CLOSID to identify a control group. When a user
creates a control group this information is not visible to the user.
It can help resctrl debugging.
Add CLOSID(ctrl_hw_id) to the control groups display in resctrl
interface. Users can see this detail when resctrl is mounted with
"-o debug" option.
Other architectures do not use "CLOSID". Use the names ctrl_hw_id
to refer to "CLOSID" in an effort to keep the naming generic.
For example:
$cat /sys/fs/resctrl/ctrl_grp1/ctrl_hw_id
1
Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
Tested-by: Peter Newman <peternewman@xxxxxxxxxx>
Reviewed-by: Peter Newman <peternewman@xxxxxxxxxx>
Tested-by: Tan Shaopeng <tan.shaopeng@xxxxxxxxxxxxxx>
Reviewed-by: Tan Shaopeng <tan.shaopeng@xxxxxxxxxxxxxx>
Reviewed-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
---
Documentation/arch/x86/resctrl.rst | 4 ++++
arch/x86/kernel/cpu/resctrl/internal.h | 3 +++
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 23 +++++++++++++++++++++++
3 files changed, 30 insertions(+)
diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst
index 28d35aaa74b4..54691c8b832d 100644
--- a/Documentation/arch/x86/resctrl.rst
+++ b/Documentation/arch/x86/resctrl.rst
@@ -352,6 +352,10 @@ When control is enabled all CTRL_MON groups will also contain:
file. On successful pseudo-locked region creation the mode will
automatically change to "pseudo-locked".
+"ctrl_hw_id":
+ Available only with debug option. The identifier used by hardware
+ for the control group. On x86 this is the CLOSID.
+
When monitoring is enabled all MON groups will also contain:
"mon_data":
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index d68f947c5a64..eda5da9ab81f 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -299,6 +299,9 @@ struct rdtgroup {
* --> RFTYPE_CTRL (Files for CTRL group)
* Files: mode, schemata, size
*
+ * --> RFTYPE_DEBUG (Files to help resctrl debugging)
+ * File: ctrl_hw_id
+ *
*/
#define RFTYPE_INFO BIT(0)
#define RFTYPE_BASE BIT(1)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 150105c21fee..953b082cec8a 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -779,6 +779,22 @@ static int rdtgroup_tasks_show(struct kernfs_open_file *of,
return ret;
}
+static int rdtgroup_closid_show(struct kernfs_open_file *of,
+ struct seq_file *s, void *v)
+{
+ struct rdtgroup *rdtgrp;
+ int ret = 0;
+
+ rdtgrp = rdtgroup_kn_lock_live(of->kn);
+ if (rdtgrp)
+ seq_printf(s, "%u\n", rdtgrp->closid);
+ else
+ ret = -ENOENT;
+ rdtgroup_kn_unlock(of->kn);
+
+ return ret;
+}
+
#ifdef CONFIG_PROC_CPU_RESCTRL
/*
@@ -1863,6 +1879,13 @@ static struct rftype res_common_files[] = {
.seq_show = rdtgroup_size_show,
.fflags = RFTYPE_CTRL_BASE,
},
+ {
+ .name = "ctrl_hw_id",
+ .mode = 0444,
+ .kf_ops = &rdtgroup_kf_single_ops,
+ .seq_show = rdtgroup_closid_show,
+ .fflags = RFTYPE_CTRL_BASE | RFTYPE_DEBUG,
+ },
};
--
2.34.1
