[PATCH RFC v2 03/19] resctrl: name node-scoped monitor domains mon_NODE_<id>
From: Fenghua Yu <fenghuay@nvidia.com>
Date: 2026-08-31 17:23:17
Also in:
lkml
Subsystem:
filesystems (vfs and infrastructure), rdt - resource allocation, the rest · Maintainers:
Alexander Viro, Christian Brauner, Tony Luck, Reinette Chatre, Linus Torvalds
Monitor domain directories under mon_data are named mon_<name>_<id>,
using the resource name as the label. For memory bandwidth monitoring on
a memory-side MSC the domain id is a NUMA node id, so labelling those
directories with the resource name ("MB") is misleading about what the
id means.
Add the RESCTRL_NODE monitor scope and a mon_domain_name() helper that
returns "NODE" for node-scoped resources (and the resource name for all
other scopes), then use it when building and removing monitor domain
directories. Node-scoped monitor domains are now named mon_NODE_<id>,
making it clear the id is a NUMA node id. L3 and telemetry naming
(mon_L3_<id>, mon_PERF_PKG_<id>) is unchanged.
Signed-off-by: Fenghua Yu <fenghuay@nvidia.com>
---
fs/resctrl/rdtgroup.c | 25 +++++++++++++++++++++----
include/linux/resctrl.h | 1 +
2 files changed, 22 insertions(+), 4 deletions(-)
diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
index a0635888a0a0..264666e54852 100644
--- a/fs/resctrl/rdtgroup.c
+++ b/fs/resctrl/rdtgroup.c@@ -3967,6 +3967,20 @@ static void mon_rmdir_one_subdir(struct kernfs_node *pkn, char *name, char *subn kernfs_remove_by_name(kn, subname); } +/* + * Label used in the mon_<label>_<id> monitor domain directory names. Node + * scoped monitoring (for example MB on a memory MSC) uses "NODE" so the id + * is understood as a NUMA node id; other scopes keep the resource name + * (L3 -> "L3", telemetry -> "PERF_PKG"). + */ +static const char *mon_domain_name(struct rdt_resource *r) +{ + if (r->mon_scope == RESCTRL_NODE) + return "NODE"; + + return r->name; +} + /* * Remove files and directories for one SNC node. If it is the last node * sharing an L3 cache, then remove the upper level directory containing
@@ -4010,7 +4024,7 @@ static void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r, return; } - sprintf(name, "mon_%s_%02d", r->name, hdr->id); + sprintf(name, "mon_%s_%02d", mon_domain_name(r), hdr->id); list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) { kernfs_remove_by_name(prgrp->mon.mon_data_kn, name);
@@ -4114,7 +4128,7 @@ static int mkdir_mondata_subdir(struct kernfs_node *parent_kn, if (r->rid == RDT_RESOURCE_L3 && r->mon_scope == RESCTRL_L3_NODE) return mkdir_mondata_subdir_snc(parent_kn, hdr, r, prgrp); - sprintf(name, "mon_%s_%02d", r->name, hdr->id); + sprintf(name, "mon_%s_%02d", mon_domain_name(r), hdr->id); kn = _mkdir_mondata_subdir(parent_kn, name, hdr, r, prgrp, hdr->id); if (IS_ERR(kn)) return PTR_ERR(kn);
@@ -4169,8 +4183,11 @@ static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn, * This creates a directory mon_data which contains the monitored data. * * mon_data has one directory for each domain which are named - * in the format mon_<domain_name>_<domain_id>. For ex: A mon_data - * with L3 domain looks as below: + * in the format mon_<domain_name>_<domain_id>. The domain name is the + * resource name for cache and telemetry scopes (for example "L3") and + * "NODE" for node scoped monitoring (for example MB on a memory MSC, + * where <domain_id> is a NUMA node id). For ex: A mon_data with L3 domain + * looks as below: * ./mon_data: * mon_L3_00 * mon_L3_01
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 54fec07bd173..f2c3621b006e 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h@@ -349,6 +349,7 @@ enum resctrl_scope { RESCTRL_L3_CACHE = 3, RESCTRL_L3_NODE, RESCTRL_PACKAGE, + RESCTRL_NODE, }; /**
--
2.53.0