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From: Tony Luck <tony.luck@intel.com>
To: Fenghua Yu <fenghuay@nvidia.com>,
	Reinette Chatre <reinette.chatre@intel.com>,
	Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com>,
	Peter Newman <peternewman@google.com>,
	James Morse <james.morse@arm.com>,
	Babu Moger <babu.moger@amd.com>,
	Drew Fustini <dfustini@baylibre.com>,
	Dave Martin <Dave.Martin@arm.com>, Chen Yu <yu.c.chen@intel.com>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
	patches@lists.linux.dev, Tony Luck <tony.luck@intel.com>
Subject: [PATCH v14 05/32] x86,fs/resctrl: Refactor domain create/remove using struct rdt_domain_hdr
Date: Mon, 24 Nov 2025 10:53:42 -0800	[thread overview]
Message-ID: <20251124185412.24155-6-tony.luck@intel.com> (raw)
In-Reply-To: <20251124185412.24155-1-tony.luck@intel.com>

Up until now, all monitoring events were associated with the L3 resource and it
made sense to use the L3 specific "struct rdt_mon_domain *" argument to functions
operating on domains.

Telemetry events will be tied to a new resource with its instances represented
by a new domain structure that, just like struct rdt_mon_domain, starts with
the generic struct rdt_domain_hdr.

Prepare to support domains belonging to different resources by changing the
calling convention of functions operating on domains.  Pass the generic header
and use that to find the domain specific structure where needed.

Signed-off-by: Tony Luck <tony.luck@intel.com>
---
 include/linux/resctrl.h            |  4 +-
 fs/resctrl/internal.h              |  2 +-
 arch/x86/kernel/cpu/resctrl/core.c |  4 +-
 fs/resctrl/ctrlmondata.c           | 14 ++++--
 fs/resctrl/rdtgroup.c              | 69 +++++++++++++++++++++---------
 5 files changed, 63 insertions(+), 30 deletions(-)

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index e7c218f8d4f7..5db37c7e89c5 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -507,9 +507,9 @@ int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_ctrl_domain *d,
 u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_ctrl_domain *d,
 			    u32 closid, enum resctrl_conf_type type);
 int resctrl_online_ctrl_domain(struct rdt_resource *r, struct rdt_ctrl_domain *d);
-int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d);
+int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr);
 void resctrl_offline_ctrl_domain(struct rdt_resource *r, struct rdt_ctrl_domain *d);
-void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d);
+void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr);
 void resctrl_online_cpu(unsigned int cpu);
 void resctrl_offline_cpu(unsigned int cpu);
 
diff --git a/fs/resctrl/internal.h b/fs/resctrl/internal.h
index bff4a54ae333..5e52269b391e 100644
--- a/fs/resctrl/internal.h
+++ b/fs/resctrl/internal.h
@@ -362,7 +362,7 @@ void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);
 
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
-		    struct rdt_mon_domain *d, struct rdtgroup *rdtgrp,
+		    struct rdt_domain_hdr *hdr, struct rdtgroup *rdtgrp,
 		    cpumask_t *cpumask, int evtid, int first);
 
 int resctrl_mon_resource_init(void);
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 64ed81cbf8bf..1fab4c67d273 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -534,7 +534,7 @@ static void l3_mon_domain_setup(int cpu, int id, struct rdt_resource *r, struct
 
 	list_add_tail_rcu(&d->hdr.list, add_pos);
 
-	err = resctrl_online_mon_domain(r, d);
+	err = resctrl_online_mon_domain(r, &d->hdr);
 	if (err) {
 		list_del_rcu(&d->hdr.list);
 		synchronize_rcu();
@@ -661,7 +661,7 @@ static void domain_remove_cpu_mon(int cpu, struct rdt_resource *r)
 
 		d = container_of(hdr, struct rdt_mon_domain, hdr);
 		hw_dom = resctrl_to_arch_mon_dom(d);
-		resctrl_offline_mon_domain(r, d);
+		resctrl_offline_mon_domain(r, hdr);
 		list_del_rcu(&hdr->list);
 		synchronize_rcu();
 		mon_domain_free(hw_dom);
diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c
index 905c310de573..3154cdc98a31 100644
--- a/fs/resctrl/ctrlmondata.c
+++ b/fs/resctrl/ctrlmondata.c
@@ -551,14 +551,21 @@ struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id,
 }
 
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
-		    struct rdt_mon_domain *d, struct rdtgroup *rdtgrp,
+		    struct rdt_domain_hdr *hdr, struct rdtgroup *rdtgrp,
 		    cpumask_t *cpumask, int evtid, int first)
 {
+	struct rdt_mon_domain *d = NULL;
 	int cpu;
 
 	/* When picking a CPU from cpu_mask, ensure it can't race with cpuhp */
 	lockdep_assert_cpus_held();
 
+	if (hdr) {
+		if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+			return;
+		d = container_of(hdr, struct rdt_mon_domain, hdr);
+	}
+
 	/*
 	 * Setup the parameters to pass to mon_event_count() to read the data.
 	 */
@@ -653,12 +660,11 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 		 * the resource to find the domain with "domid".
 		 */
 		hdr = resctrl_find_domain(&r->mon_domains, domid, NULL);
-		if (!hdr || !domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, resid)) {
+		if (!hdr) {
 			ret = -ENOENT;
 			goto out;
 		}
-		d = container_of(hdr, struct rdt_mon_domain, hdr);
-		mon_event_read(&rr, r, d, rdtgrp, &d->hdr.cpu_mask, evtid, false);
+		mon_event_read(&rr, r, hdr, rdtgrp, &hdr->cpu_mask, evtid, false);
 	}
 
 checkresult:
diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
index 8e39dfda56bc..89ffe54fb0fc 100644
--- a/fs/resctrl/rdtgroup.c
+++ b/fs/resctrl/rdtgroup.c
@@ -3229,17 +3229,22 @@ static void mon_rmdir_one_subdir(struct kernfs_node *pkn, char *name, char *subn
  * when last domain being summed is removed.
  */
 static void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
-					   struct rdt_mon_domain *d)
+					   struct rdt_domain_hdr *hdr)
 {
 	struct rdtgroup *prgrp, *crgrp;
+	struct rdt_mon_domain *d;
 	char subname[32];
 	bool snc_mode;
 	char name[32];
 
+	if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+		return;
+
+	d = container_of(hdr, struct rdt_mon_domain, hdr);
 	snc_mode = r->mon_scope == RESCTRL_L3_NODE;
-	sprintf(name, "mon_%s_%02d", r->name, snc_mode ? d->ci_id : d->hdr.id);
+	sprintf(name, "mon_%s_%02d", r->name, snc_mode ? d->ci_id : hdr->id);
 	if (snc_mode)
-		sprintf(subname, "mon_sub_%s_%02d", r->name, d->hdr.id);
+		sprintf(subname, "mon_sub_%s_%02d", r->name, hdr->id);
 
 	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
 		mon_rmdir_one_subdir(prgrp->mon.mon_data_kn, name, subname);
@@ -3249,15 +3254,20 @@ static void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
 	}
 }
 
-static int mon_add_all_files(struct kernfs_node *kn, struct rdt_mon_domain *d,
+static int mon_add_all_files(struct kernfs_node *kn, struct rdt_domain_hdr *hdr,
 			     struct rdt_resource *r, struct rdtgroup *prgrp,
 			     bool do_sum)
 {
 	struct rmid_read rr = {0};
+	struct rdt_mon_domain *d;
 	struct mon_data *priv;
 	struct mon_evt *mevt;
 	int ret, domid;
 
+	if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+		return -EINVAL;
+
+	d = container_of(hdr, struct rdt_mon_domain, hdr);
 	for_each_mon_event(mevt) {
 		if (mevt->rid != r->rid || !mevt->enabled)
 			continue;
@@ -3271,23 +3281,28 @@ static int mon_add_all_files(struct kernfs_node *kn, struct rdt_mon_domain *d,
 			return ret;
 
 		if (!do_sum && resctrl_is_mbm_event(mevt->evtid))
-			mon_event_read(&rr, r, d, prgrp, &d->hdr.cpu_mask, mevt->evtid, true);
+			mon_event_read(&rr, r, hdr, prgrp, &hdr->cpu_mask, mevt->evtid, true);
 	}
 
 	return 0;
 }
 
 static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
-				struct rdt_mon_domain *d,
+				struct rdt_domain_hdr *hdr,
 				struct rdt_resource *r, struct rdtgroup *prgrp)
 {
 	struct kernfs_node *kn, *ckn;
+	struct rdt_mon_domain *d;
 	char name[32];
 	bool snc_mode;
 	int ret = 0;
 
 	lockdep_assert_held(&rdtgroup_mutex);
 
+	if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+		return -EINVAL;
+
+	d = container_of(hdr, struct rdt_mon_domain, hdr);
 	snc_mode = r->mon_scope == RESCTRL_L3_NODE;
 	sprintf(name, "mon_%s_%02d", r->name, snc_mode ? d->ci_id : d->hdr.id);
 	kn = kernfs_find_and_get(parent_kn, name);
@@ -3305,13 +3320,13 @@ static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
 		ret = rdtgroup_kn_set_ugid(kn);
 		if (ret)
 			goto out_destroy;
-		ret = mon_add_all_files(kn, d, r, prgrp, snc_mode);
+		ret = mon_add_all_files(kn, hdr, r, prgrp, snc_mode);
 		if (ret)
 			goto out_destroy;
 	}
 
 	if (snc_mode) {
-		sprintf(name, "mon_sub_%s_%02d", r->name, d->hdr.id);
+		sprintf(name, "mon_sub_%s_%02d", r->name, hdr->id);
 		ckn = kernfs_create_dir(kn, name, parent_kn->mode, prgrp);
 		if (IS_ERR(ckn)) {
 			ret = -EINVAL;
@@ -3322,7 +3337,7 @@ static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
 		if (ret)
 			goto out_destroy;
 
-		ret = mon_add_all_files(ckn, d, r, prgrp, false);
+		ret = mon_add_all_files(ckn, hdr, r, prgrp, false);
 		if (ret)
 			goto out_destroy;
 	}
@@ -3340,7 +3355,7 @@ static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
  * and "monitor" groups with given domain id.
  */
 static void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
-					   struct rdt_mon_domain *d)
+					   struct rdt_domain_hdr *hdr)
 {
 	struct kernfs_node *parent_kn;
 	struct rdtgroup *prgrp, *crgrp;
@@ -3348,12 +3363,12 @@ static void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
 
 	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
 		parent_kn = prgrp->mon.mon_data_kn;
-		mkdir_mondata_subdir(parent_kn, d, r, prgrp);
+		mkdir_mondata_subdir(parent_kn, hdr, r, prgrp);
 
 		head = &prgrp->mon.crdtgrp_list;
 		list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
 			parent_kn = crgrp->mon.mon_data_kn;
-			mkdir_mondata_subdir(parent_kn, d, r, crgrp);
+			mkdir_mondata_subdir(parent_kn, hdr, r, crgrp);
 		}
 	}
 }
@@ -3362,14 +3377,14 @@ static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn,
 				       struct rdt_resource *r,
 				       struct rdtgroup *prgrp)
 {
-	struct rdt_mon_domain *dom;
+	struct rdt_domain_hdr *hdr;
 	int ret;
 
 	/* Walking r->domains, ensure it can't race with cpuhp */
 	lockdep_assert_cpus_held();
 
-	list_for_each_entry(dom, &r->mon_domains, hdr.list) {
-		ret = mkdir_mondata_subdir(parent_kn, dom, r, prgrp);
+	list_for_each_entry(hdr, &r->mon_domains, list) {
+		ret = mkdir_mondata_subdir(parent_kn, hdr, r, prgrp);
 		if (ret)
 			return ret;
 	}
@@ -4253,16 +4268,23 @@ void resctrl_offline_ctrl_domain(struct rdt_resource *r, struct rdt_ctrl_domain
 	mutex_unlock(&rdtgroup_mutex);
 }
 
-void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d)
+void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr)
 {
+	struct rdt_mon_domain *d;
+
 	mutex_lock(&rdtgroup_mutex);
 
+	if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+		goto out_unlock;
+
+	d = container_of(hdr, struct rdt_mon_domain, hdr);
+
 	/*
 	 * If resctrl is mounted, remove all the
 	 * per domain monitor data directories.
 	 */
 	if (resctrl_mounted && resctrl_arch_mon_capable())
-		rmdir_mondata_subdir_allrdtgrp(r, d);
+		rmdir_mondata_subdir_allrdtgrp(r, hdr);
 
 	if (resctrl_is_mbm_enabled())
 		cancel_delayed_work(&d->mbm_over);
@@ -4280,7 +4302,7 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d
 	}
 
 	domain_destroy_mon_state(d);
-
+out_unlock:
 	mutex_unlock(&rdtgroup_mutex);
 }
 
@@ -4353,12 +4375,17 @@ int resctrl_online_ctrl_domain(struct rdt_resource *r, struct rdt_ctrl_domain *d
 	return err;
 }
 
-int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d)
+int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr)
 {
-	int err;
+	struct rdt_mon_domain *d;
+	int err = -EINVAL;
 
 	mutex_lock(&rdtgroup_mutex);
 
+	if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+		goto out_unlock;
+
+	d = container_of(hdr, struct rdt_mon_domain, hdr);
 	err = domain_setup_mon_state(r, d);
 	if (err)
 		goto out_unlock;
@@ -4379,7 +4406,7 @@ int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d)
 	 * If resctrl is mounted, add per domain monitor data directories.
 	 */
 	if (resctrl_mounted && resctrl_arch_mon_capable())
-		mkdir_mondata_subdir_allrdtgrp(r, d);
+		mkdir_mondata_subdir_allrdtgrp(r, hdr);
 
 out_unlock:
 	mutex_unlock(&rdtgroup_mutex);
-- 
2.51.1


  parent reply	other threads:[~2025-11-24 18:54 UTC|newest]

Thread overview: 55+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-24 18:53 [PATCH v14 00/32] x86,fs/resctrl telemetry monitoring Tony Luck
2025-11-24 18:53 ` [PATCH v14 01/32] x86,fs/resctrl: Improve domain type checking Tony Luck
2025-11-24 18:53 ` [PATCH v14 02/32] x86/resctrl: Move L3 initialization into new helper function Tony Luck
2025-11-24 18:53 ` [PATCH v14 03/32] x86/resctrl: Refactor domain_remove_cpu_mon() ready for new domain types Tony Luck
2025-12-02 16:01   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 04/32] x86/resctrl: Clean up domain_remove_cpu_ctrl() Tony Luck
2025-11-24 18:53 ` Tony Luck [this message]
2025-12-02 16:01   ` [PATCH v14 05/32] x86,fs/resctrl: Refactor domain create/remove using struct rdt_domain_hdr Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 06/32] fs/resctrl: Split L3 dependent parts out of __mon_event_count() Tony Luck
2025-12-02 16:02   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 07/32] x86,fs/resctrl: Use struct rdt_domain_hdr when reading counters Tony Luck
2025-12-02 16:06   ` Reinette Chatre
2025-12-02 20:33     ` Luck, Tony
2025-12-02 22:24       ` Reinette Chatre
2025-12-02 23:22         ` Luck, Tony
2025-11-24 18:53 ` [PATCH v14 08/32] x86,fs/resctrl: Rename struct rdt_mon_domain and rdt_hw_mon_domain Tony Luck
2025-12-02 16:07   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 09/32] x86,fs/resctrl: Rename some L3 specific functions Tony Luck
2025-11-24 18:53 ` [PATCH v14 10/32] fs/resctrl: Make event details accessible to functions when reading events Tony Luck
2025-11-24 18:53 ` [PATCH v14 11/32] x86,fs/resctrl: Handle events that can be read from any CPU Tony Luck
2025-12-02 16:08   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 12/32] x86,fs/resctrl: Support binary fixed point event counters Tony Luck
2025-12-02 16:11   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 13/32] x86,fs/resctrl: Add an architectural hook called for each mount Tony Luck
2025-11-24 18:53 ` [PATCH v14 14/32] x86,fs/resctrl: Add and initialize rdt_resource for package scope monitor Tony Luck
2025-12-02 16:11   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 15/32] fs/resctrl: Emphasize that L3 monitoring resource is required for summing domains Tony Luck
2025-11-24 18:53 ` [PATCH v14 16/32] x86/resctrl: Discover hardware telemetry events Tony Luck
2025-12-02 16:18   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 17/32] x86,fs/resctrl: Fill in details of events for guid 0x26696143 and 0x26557651 Tony Luck
2025-12-02 16:19   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 18/32] x86,fs/resctrl: Add architectural event pointer Tony Luck
2025-11-24 18:53 ` [PATCH v14 19/32] x86/resctrl: Find and enable usable telemetry events Tony Luck
2025-12-02 16:21   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 20/32] x86/resctrl: Read " Tony Luck
2025-12-02 16:21   ` Reinette Chatre
2025-11-24 18:53 ` [PATCH v14 21/32] fs/resctrl: Refactor mkdir_mondata_subdir() Tony Luck
2025-11-24 18:53 ` [PATCH v14 22/32] fs/resctrl: Refactor rmdir_mondata_subdir_allrdtgrp() Tony Luck
2025-11-24 18:54 ` [PATCH v14 23/32] x86,fs/resctrl: Handle domain creation/deletion for RDT_RESOURCE_PERF_PKG Tony Luck
2025-11-24 18:54 ` [PATCH v14 24/32] x86/resctrl: Add energy/perf choices to rdt boot option Tony Luck
2025-12-02 16:28   ` Reinette Chatre
2025-12-03 18:04     ` Luck, Tony
2025-12-03 21:21       ` Reinette Chatre
2025-12-03 22:27         ` Luck, Tony
2025-12-03 23:25           ` Reinette Chatre
2025-11-24 18:54 ` [PATCH v14 25/32] x86/resctrl: Handle number of RMIDs supported by RDT_RESOURCE_PERF_PKG Tony Luck
2025-12-02 16:31   ` Reinette Chatre
2025-11-24 18:54 ` [PATCH v14 26/32] fs/resctrl: Move allocation/free of closid_num_dirty_rmid[] Tony Luck
2025-11-24 18:54 ` [PATCH v14 27/32] x86,fs/resctrl: Compute number of RMIDs as minimum across resources Tony Luck
2025-11-24 18:54 ` [PATCH v14 28/32] fs/resctrl: Move RMID initialization to first mount Tony Luck
2025-11-24 18:54 ` [PATCH v14 29/32] x86/resctrl: Enable RDT_RESOURCE_PERF_PKG Tony Luck
2025-11-24 18:54 ` [PATCH v14 30/32] fs/resctrl: Provide interface to create architecture specific debugfs area Tony Luck
2025-11-24 18:54 ` [PATCH v14 31/32] x86/resctrl: Add debugfs files to show telemetry aggregator status Tony Luck
2025-11-24 18:54 ` [PATCH v14 32/32] x86,fs/resctrl: Update documentation for telemetry events Tony Luck
2025-12-02 16:34   ` Reinette Chatre

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