Commit 4cee14bc authored by Babu Moger's avatar Babu Moger Committed by Borislav Petkov (AMD)
Browse files

x86/resctrl: Display RMID of resource group 



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: default avatarBabu Moger <babu.moger@amd.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: default avatarPeter Newman <peternewman@google.com>
Reviewed-by: default avatarTan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: default avatarFenghua Yu <fenghua.yu@intel.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: default avatarPeter Newman <peternewman@google.com>
Tested-by: default avatarTan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-10-babu.moger@amd.com
parent 918f211b

Documentation/arch/x86/resctrl.rst

+4 −0
Original line number Diff line number Diff line
@@ -376,6 +376,10 @@ 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

-------------------------

arch/x86/kernel/cpu/resctrl/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -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;

arch/x86/kernel/cpu/resctrl/rdtgroup.c

+23 −0
Original line number Diff line number Diff line
@@ -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,