x86/resctrl: Prepare for different scope for control/monitor operations

Resctrl assumes that control and monitor operations on a resource are
performed at the same scope.

Prepare for systems that use different scope (specifically Intel needs
to split the RDT_RESOURCE_L3 resource to use L3 scope for cache control
and NODE scope for cache occupancy and memory bandwidth monitoring).

Create separate domain lists for control and monitor operations.

Note that errors during initialization of either control or monitor
functions on a domain would previously result in that domain being
excluded from both control and monitor operations. Now the domains are
allocated independently it is no longer required to disable both control
and monitor operations if either fail.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20240628215619.76401-4-tony.luck@intel.com

1 files changed, 35 insertions, 25 deletions

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index b6ba77cdf0e8..17d4610eecf5 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -98,7 +98,7 @@ void rdt_staged_configs_clear(void)
 	lockdep_assert_held(&rdtgroup_mutex);
 
 	for_each_alloc_capable_rdt_resource(r) {
-		list_for_each_entry(dom, &r->domains, hdr.list)
+		list_for_each_entry(dom, &r->ctrl_domains, hdr.list)
 			memset(dom->staged_config, 0, sizeof(dom->staged_config));
 	}
 }
@@ -1021,7 +1021,7 @@ static int rdt_bit_usage_show(struct kernfs_open_file *of,
 	cpus_read_lock();
 	mutex_lock(&rdtgroup_mutex);
 	hw_shareable = r->cache.shareable_bits;
-	list_for_each_entry(dom, &r->domains, hdr.list) {
+	list_for_each_entry(dom, &r->ctrl_domains, hdr.list) {
 		if (sep)
 			seq_putc(seq, ';');
 		sw_shareable = 0;
@@ -1343,7 +1343,7 @@ static bool rdtgroup_mode_test_exclusive(struct rdtgroup *rdtgrp)
 		if (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)
 			continue;
 		has_cache = true;
-		list_for_each_entry(d, &r->domains, hdr.list) {
+		list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
 			ctrl = resctrl_arch_get_config(r, d, closid,
 						       s->conf_type);
 			if (rdtgroup_cbm_overlaps(s, d, ctrl, closid, false)) {
@@ -1454,11 +1454,11 @@ unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
 	struct cacheinfo *ci;
 	int num_b;
 
-	if (WARN_ON_ONCE(r->scope != RESCTRL_L2_CACHE && r->scope != RESCTRL_L3_CACHE))
+	if (WARN_ON_ONCE(r->ctrl_scope != RESCTRL_L2_CACHE && r->ctrl_scope != RESCTRL_L3_CACHE))
 		return size;
 
 	num_b = bitmap_weight(&cbm, r->cache.cbm_len);
-	ci = get_cpu_cacheinfo_level(cpumask_any(&d->hdr.cpu_mask), r->scope);
+	ci = get_cpu_cacheinfo_level(cpumask_any(&d->hdr.cpu_mask), r->ctrl_scope);
 	if (ci)
 		size = ci->size / r->cache.cbm_len * num_b;
 
@@ -1514,7 +1514,7 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
 		type = schema->conf_type;
 		sep = false;
 		seq_printf(s, "%*s:", max_name_width, schema->name);
-		list_for_each_entry(d, &r->domains, hdr.list) {
+		list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
 			if (sep)
 				seq_putc(s, ';');
 			if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
@@ -1604,7 +1604,7 @@ static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid
 	cpus_read_lock();
 	mutex_lock(&rdtgroup_mutex);
 
-	list_for_each_entry(dom, &r->domains, hdr.list) {
+	list_for_each_entry(dom, &r->mon_domains, hdr.list) {
 		if (sep)
 			seq_puts(s, ";");
 
@@ -1728,7 +1728,7 @@ next:
 		return -EINVAL;
 	}
 
-	list_for_each_entry(d, &r->domains, hdr.list) {
+	list_for_each_entry(d, &r->mon_domains, hdr.list) {
 		if (d->hdr.id == dom_id) {
 			mbm_config_write_domain(r, d, evtid, val);
 			goto next;
@@ -2276,7 +2276,7 @@ static int set_cache_qos_cfg(int level, bool enable)
 		return -ENOMEM;
 
 	r_l = &rdt_resources_all[level].r_resctrl;
-	list_for_each_entry(d, &r_l->domains, hdr.list) {
+	list_for_each_entry(d, &r_l->ctrl_domains, hdr.list) {
 		if (r_l->cache.arch_has_per_cpu_cfg)
 			/* Pick all the CPUs in the domain instance */
 			for_each_cpu(cpu, &d->hdr.cpu_mask)
@@ -2361,7 +2361,7 @@ static int set_mba_sc(bool mba_sc)
 
 	r->membw.mba_sc = mba_sc;
 
-	list_for_each_entry(d, &r->domains, hdr.list) {
+	list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
 		for (i = 0; i < num_closid; i++)
 			d->mbps_val[i] = MBA_MAX_MBPS;
 	}
@@ -2700,7 +2700,7 @@ static int rdt_get_tree(struct fs_context *fc)
 
 	if (is_mbm_enabled()) {
 		r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
-		list_for_each_entry(dom, &r->domains, hdr.list)
+		list_for_each_entry(dom, &r->mon_domains, hdr.list)
 			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL,
 						   RESCTRL_PICK_ANY_CPU);
 	}
@@ -2824,10 +2824,10 @@ static int reset_all_ctrls(struct rdt_resource *r)
 
 	/*
 	 * Disable resource control for this resource by setting all
-	 * CBMs in all domains to the maximum mask value. Pick one CPU
+	 * CBMs in all ctrl_domains to the maximum mask value. Pick one CPU
 	 * from each domain to update the MSRs below.
 	 */
-	list_for_each_entry(d, &r->domains, hdr.list) {
+	list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
 		hw_dom = resctrl_to_arch_dom(d);
 
 		for (i = 0; i < hw_res->num_closid; i++)
@@ -3098,7 +3098,7 @@ static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn,
 	/* Walking r->domains, ensure it can't race with cpuhp */
 	lockdep_assert_cpus_held();
 
-	list_for_each_entry(dom, &r->domains, hdr.list) {
+	list_for_each_entry(dom, &r->mon_domains, hdr.list) {
 		ret = mkdir_mondata_subdir(parent_kn, dom, r, prgrp);
 		if (ret)
 			return ret;
@@ -3280,7 +3280,7 @@ static int rdtgroup_init_cat(struct resctrl_schema *s, u32 closid)
 	struct rdt_domain *d;
 	int ret;
 
-	list_for_each_entry(d, &s->res->domains, hdr.list) {
+	list_for_each_entry(d, &s->res->ctrl_domains, hdr.list) {
 		ret = __init_one_rdt_domain(d, s, closid);
 		if (ret < 0)
 			return ret;
@@ -3295,7 +3295,7 @@ static void rdtgroup_init_mba(struct rdt_resource *r, u32 closid)
 	struct resctrl_staged_config *cfg;
 	struct rdt_domain *d;
 
-	list_for_each_entry(d, &r->domains, hdr.list) {
+	list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
 		if (is_mba_sc(r)) {
 			d->mbps_val[closid] = MBA_MAX_MBPS;
 			continue;
@@ -3926,15 +3926,19 @@ static void domain_destroy_mon_state(struct rdt_domain *d)
 	kfree(d->mbm_local);
 }
 
-void resctrl_offline_domain(struct rdt_resource *r, struct rdt_domain *d)
+void resctrl_offline_ctrl_domain(struct rdt_resource *r, struct rdt_domain *d)
 {
 	mutex_lock(&rdtgroup_mutex);
 
 	if (supports_mba_mbps() && r->rid == RDT_RESOURCE_MBA)
 		mba_sc_domain_destroy(r, d);
 
-	if (!r->mon_capable)
-		goto out_unlock;
+	mutex_unlock(&rdtgroup_mutex);
+}
+
+void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_domain *d)
+{
+	mutex_lock(&rdtgroup_mutex);
 
 	/*
 	 * If resctrl is mounted, remove all the
@@ -3960,7 +3964,6 @@ void resctrl_offline_domain(struct rdt_resource *r, struct rdt_domain *d)
 
 	domain_destroy_mon_state(d);
 
-out_unlock:
 	mutex_unlock(&rdtgroup_mutex);
 }
 
@@ -3995,7 +3998,7 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
 	return 0;
 }
 
-int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d)
+int resctrl_online_ctrl_domain(struct rdt_resource *r, struct rdt_domain *d)
 {
 	int err = 0;
 
@@ -4004,11 +4007,18 @@ int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d)
 	if (supports_mba_mbps() && r->rid == RDT_RESOURCE_MBA) {
 		/* RDT_RESOURCE_MBA is never mon_capable */
 		err = mba_sc_domain_allocate(r, d);
-		goto out_unlock;
 	}
 
-	if (!r->mon_capable)
-		goto out_unlock;
+	mutex_unlock(&rdtgroup_mutex);
+
+	return err;
+}
+
+int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_domain *d)
+{
+	int err;
+
+	mutex_lock(&rdtgroup_mutex);
 
 	err = domain_setup_mon_state(r, d);
 	if (err)
@@ -4073,7 +4083,7 @@ void resctrl_offline_cpu(unsigned int cpu)
 	if (!l3->mon_capable)
 		goto out_unlock;
 
-	d = get_domain_from_cpu(cpu, l3);
+	d = get_mon_domain_from_cpu(cpu, l3);
 	if (d) {
 		if (is_mbm_enabled() && cpu == d->mbm_work_cpu) {
 			cancel_delayed_work(&d->mbm_over);