From: Babu Moger babu.moger@amd.com
In x86, hardware uses RMID to identify a monitoring group. When a user creates a monitor group these details are not visible. These details can help resctrl debugging.
Add RMID(mon_hw_id) to the monitor groups display in the resctrl interface. Users can see these details when resctrl is mounted with "-o debug" option.
Add RFTYPE_MON_BASE that complements existing RFTYPE_CTRL_BASE and represents files belonging to monitoring groups.
Other architectures do not use "RMID". Use the name mon_hw_id to refer to "RMID" in an effort to keep the naming generic.
For example: $cat /sys/fs/resctrl/mon_groups/mon_grp1/mon_hw_id 3
Signed-off-by: Babu Moger babu.moger@amd.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Reviewed-by: Peter Newman peternewman@google.com Reviewed-by: Tan Shaopeng tan.shaopeng@jp.fujitsu.com Reviewed-by: Fenghua Yu fenghua.yu@intel.com Reviewed-by: Reinette Chatre reinette.chatre@intel.com Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Tested-by: Peter Newman peternewman@google.com Tested-by: Tan Shaopeng tan.shaopeng@jp.fujitsu.com Link: https://lore.kernel.org/r/20231017002308.134480-10-babu.moger@amd.com --- Documentation/arch/x86/resctrl.rst | 4 ++++ arch/x86/kernel/cpu/resctrl/internal.h | 1 + arch/x86/kernel/cpu/resctrl/rdtgroup.c | 23 +++++++++++++++++++++++ 3 files changed, 28 insertions(+)
diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst index 54691c8b832d..98b0eb509ed4 100644 --- a/Documentation/arch/x86/resctrl.rst +++ b/Documentation/arch/x86/resctrl.rst @@ -369,6 +369,10 @@ When monitoring is enabled all MON groups will also contain: the sum for all tasks in the CTRL_MON group and all tasks in MON groups. Please see example section for more details on usage.
+"mon_hw_id": + Available only with debug option. The identifier used by hardware + for the monitor group. On x86 this is the RMID. + Resource allocation rules -------------------------
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index b816b902b5c0..a4f1aa15f0a2 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -254,6 +254,7 @@ struct rdtgroup { #define RFTYPE_MON_INFO (RFTYPE_INFO | RFTYPE_MON) #define RFTYPE_TOP_INFO (RFTYPE_INFO | RFTYPE_TOP) #define RFTYPE_CTRL_BASE (RFTYPE_BASE | RFTYPE_CTRL) +#define RFTYPE_MON_BASE (RFTYPE_BASE | RFTYPE_MON)
/* List of all resource groups */ extern struct list_head rdt_all_groups; diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 5f6d6ba63a2e..69a1de92384a 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -795,6 +795,22 @@ static int rdtgroup_closid_show(struct kernfs_open_file *of, return ret; }
+static int rdtgroup_rmid_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->mon.rmid); + else + ret = -ENOENT; + rdtgroup_kn_unlock(of->kn); + + return ret; +} + #ifdef CONFIG_PROC_CPU_RESCTRL
/* @@ -1867,6 +1883,13 @@ static struct rftype res_common_files[] = { .seq_show = rdtgroup_tasks_show, .fflags = RFTYPE_BASE, }, + { + .name = "mon_hw_id", + .mode = 0444, + .kf_ops = &rdtgroup_kf_single_ops, + .seq_show = rdtgroup_rmid_show, + .fflags = RFTYPE_MON_BASE | RFTYPE_DEBUG, + }, { .name = "schemata", .mode = 0644,