x86,fs/resctrl: Handle domain creation/deletion for RDT_RESOURCE_PERF_PKG

The L3 resource has several requirements for domains. There are per-domain
structures that hold the 64-bit values of counters, and elements to keep
track of the overflow and limbo threads.

None of these are needed for the PERF_PKG resource. The hardware counters
are wide enough that they do not wrap around for decades.

Define a new rdt_perf_pkg_mon_domain structure which just consists of the
standard rdt_domain_hdr to keep track of domain id and CPU mask.

Update resctrl_online_mon_domain() for RDT_RESOURCE_PERF_PKG. The only action
needed for this resource is to create and populate domain directories if a
domain is added while resctrl is mounted.

Similarly resctrl_offline_mon_domain() only needs to remove domain directories.

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>
Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 509277b17b9eeb2e878ec72750cbc482a8c57a80..2514f15cd9a447af76785cf57b1dfe34d6afd4ad 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -580,6 +580,10 @@ static void domain_add_cpu_mon(int cpu, struct rdt_resource *r)
                if (!hdr)
                        l3_mon_domain_setup(cpu, id, r, add_pos);
                break;
+       case RDT_RESOURCE_PERF_PKG:
+               if (!hdr)
+                       intel_aet_mon_domain_setup(cpu, id, r, add_pos);
+               break;
        default:
                pr_warn_once("Unknown resource rid=%d\n", r->rid);
                break;
@@ -679,6 +683,19 @@ static void domain_remove_cpu_mon(int cpu, struct rdt_resource *r)
                l3_mon_domain_free(hw_dom);
                break;
        }
+       case RDT_RESOURCE_PERF_PKG: {
+               struct rdt_perf_pkg_mon_domain *pkgd;
+
+               if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_PERF_PKG))
+                       return;
+
+               pkgd = container_of(hdr, struct rdt_perf_pkg_mon_domain, hdr);
+               resctrl_offline_mon_domain(r, hdr);
+               list_del_rcu(&hdr->list);
+               synchronize_rcu();
+               kfree(pkgd);
+               break;
+       }
        default:
                pr_warn_once("Unknown resource rid=%d\n", r->rid);
                break;

diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c
index 96d627e2c52d082be754c31cddc4a96275e8b508..9351fe5b645af1ae26bd0102cddcd1c16036b3e4 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/intel_aet.c
+++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c
@@ -14,15 +14,20 @@
 #include <linux/bits.h>
 #include <linux/compiler_types.h>
 #include <linux/container_of.h>
+#include <linux/cpumask.h>
 #include <linux/err.h>
 #include <linux/errno.h>
+#include <linux/gfp_types.h>
 #include <linux/init.h>
 #include <linux/intel_pmt_features.h>
 #include <linux/intel_vsec.h>
 #include <linux/io.h>
 #include <linux/printk.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
 #include <linux/resctrl.h>
 #include <linux/resctrl_types.h>
+#include <linux/slab.h>
 #include <linux/stddef.h>
 #include <linux/topology.h>
 #include <linux/types.h>
@@ -283,3 +288,27 @@ int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64 *val)
 
        return valid ? 0 : -EINVAL;
 }
+
+void intel_aet_mon_domain_setup(int cpu, int id, struct rdt_resource *r,
+                               struct list_head *add_pos)
+{
+       struct rdt_perf_pkg_mon_domain *d;
+       int err;
+
+       d = kzalloc_node(sizeof(*d), GFP_KERNEL, cpu_to_node(cpu));
+       if (!d)
+               return;
+
+       d->hdr.id = id;
+       d->hdr.type = RESCTRL_MON_DOMAIN;
+       d->hdr.rid = RDT_RESOURCE_PERF_PKG;
+       cpumask_set_cpu(cpu, &d->hdr.cpu_mask);
+       list_add_tail_rcu(&d->hdr.list, add_pos);
+
+       err = resctrl_online_mon_domain(r, &d->hdr);
+       if (err) {
+               list_del_rcu(&d->hdr.list);
+               synchronize_rcu();
+               kfree(d);
+       }
+}

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 10743f5d5fd484e8b5e71a73b1f1c35aea84d31d..3b228b241fb28c3a58cc9435f6db09399897b8c2 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -87,6 +87,14 @@ static inline struct rdt_hw_l3_mon_domain *resctrl_to_arch_mon_dom(struct rdt_l3
        return container_of(r, struct rdt_hw_l3_mon_domain, d_resctrl);
 }
 
+/**
+ * struct rdt_perf_pkg_mon_domain - CPUs sharing an package scoped resctrl monitor resource
+ * @hdr:       common header for different domain types
+ */
+struct rdt_perf_pkg_mon_domain {
+       struct rdt_domain_hdr   hdr;
+};
+
 /**
  * struct msr_param - set a range of MSRs from a domain
  * @res:       The resource to use
@@ -226,6 +234,8 @@ void resctrl_arch_mbm_cntr_assign_set_one(struct rdt_resource *r);
 bool intel_aet_get_events(void);
 void __exit intel_aet_exit(void);
 int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64 *val);
+void intel_aet_mon_domain_setup(int cpu, int id, struct rdt_resource *r,
+                               struct list_head *add_pos);
 #else
 static inline bool intel_aet_get_events(void) { return false; }
 static inline void __exit intel_aet_exit(void) { }
@@ -233,6 +243,9 @@ static inline int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64
 {
        return -EINVAL;
 }
+
+static inline void intel_aet_mon_domain_setup(int cpu, int id, struct rdt_resource *r,
+                                             struct list_head *add_pos) { }
 #endif
 
 #endif /* _ASM_X86_RESCTRL_INTERNAL_H */

diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
index 57139f9a30e7d3a8f3524bd7284dd00d9163e14f..b9363a938f742e5de89b8d3302362eadadcaf64c 100644 (file)
--- a/fs/resctrl/rdtgroup.c
+++ b/fs/resctrl/rdtgroup.c
@@ -4308,11 +4308,6 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *h
 
        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_l3_mon_domain, hdr);
-
        /*
         * If resctrl is mounted, remove all the
         * per domain monitor data directories.
@@ -4320,6 +4315,13 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *h
        if (resctrl_mounted && resctrl_arch_mon_capable())
                rmdir_mondata_subdir_allrdtgrp(r, hdr);
 
+       if (r->rid != RDT_RESOURCE_L3)
+               goto out_unlock;
+
+       if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+               goto out_unlock;
+
+       d = container_of(hdr, struct rdt_l3_mon_domain, hdr);
        if (resctrl_is_mbm_enabled())
                cancel_delayed_work(&d->mbm_over);
        if (resctrl_is_mon_event_enabled(QOS_L3_OCCUP_EVENT_ID) && has_busy_rmid(d)) {
@@ -4416,6 +4418,9 @@ int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr
 
        mutex_lock(&rdtgroup_mutex);
 
+       if (r->rid != RDT_RESOURCE_L3)
+               goto mkdir;
+
        if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
                goto out_unlock;
 
@@ -4433,6 +4438,8 @@ int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr
        if (resctrl_is_mon_event_enabled(QOS_L3_OCCUP_EVENT_ID))
                INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
 
+mkdir:
+       err = 0;
        /*
         * If the filesystem is not mounted then only the default resource group
         * exists. Creation of its directories is deferred until mount time