x86/resctrl: Read telemetry events

Introduce intel_aet_read_event() to read telemetry events for resource
RDT_RESOURCE_PERF_PKG. There may be multiple aggregators tracking each
package, so scan all of them and add up all counters. Aggregators may return
an invalid data indication if they have received no records for a given RMID.
The user will see "Unavailable" if none of the aggregators on a package
provide valid counts.

Resctrl now uses readq() so depends on X86_64. Update Kconfig.

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/Kconfig b/arch/x86/Kconfig
index 0d874a92daeda7062054b9fb9e2c42a079f5ca36..c25ea0f139cacf32e7abfd63f54e4c6e41a50d48 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -542,7 +542,7 @@ config X86_CPU_RESCTRL
 
 config X86_CPU_RESCTRL_INTEL_AET
        bool "Intel Application Energy Telemetry"
-       depends on X86_CPU_RESCTRL && CPU_SUP_INTEL && INTEL_PMT_TELEMETRY=y && INTEL_TPMI=y
+       depends on X86_64 && X86_CPU_RESCTRL && CPU_SUP_INTEL && INTEL_PMT_TELEMETRY=y && INTEL_TPMI=y
        help
          Enable per-RMID telemetry events in resctrl.
 

diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c
index 7d0bd7b070a796d08a79cbf95165e57329dfff28..96d627e2c52d082be754c31cddc4a96275e8b508 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/intel_aet.c
+++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c
@@ -11,11 +11,15 @@
 
 #define pr_fmt(fmt)   "resctrl: " fmt
 
+#include <linux/bits.h>
 #include <linux/compiler_types.h>
+#include <linux/container_of.h>
 #include <linux/err.h>
+#include <linux/errno.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/resctrl.h>
 #include <linux/resctrl_types.h>
@@ -232,3 +236,50 @@ void __exit intel_aet_exit(void)
                }
        }
 }
+
+#define DATA_VALID     BIT_ULL(63)
+#define DATA_BITS      GENMASK_ULL(62, 0)
+
+/*
+ * Read counter for an event on a domain (summing all aggregators on the
+ * domain). If an aggregator hasn't received any data for a specific RMID,
+ * the MMIO read indicates that data is not valid.  Return success if at
+ * least one aggregator has valid data.
+ */
+int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64 *val)
+{
+       struct pmt_event *pevt = arch_priv;
+       struct event_group *e;
+       bool valid = false;
+       u64 total = 0;
+       u64 evtcount;
+       void *pevt0;
+       u32 idx;
+
+       pevt0 = pevt - pevt->idx;
+       e = container_of(pevt0, struct event_group, evts);
+       idx = rmid * e->num_events;
+       idx += pevt->idx;
+
+       if (idx * sizeof(u64) + sizeof(u64) > e->mmio_size) {
+               pr_warn_once("MMIO index %u out of range\n", idx);
+               return -EIO;
+       }
+
+       for (int i = 0; i < e->pfg->count; i++) {
+               if (!e->pfg->regions[i].addr)
+                       continue;
+               if (e->pfg->regions[i].plat_info.package_id != domid)
+                       continue;
+               evtcount = readq(e->pfg->regions[i].addr + idx * sizeof(u64));
+               if (!(evtcount & DATA_VALID))
+                       continue;
+               total += evtcount & DATA_BITS;
+               valid = true;
+       }
+
+       if (valid)
+               *val = total;
+
+       return valid ? 0 : -EINVAL;
+}

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index f2e6e3577df03264ebf054a42c955641ba7bcc58..10743f5d5fd484e8b5e71a73b1f1c35aea84d31d 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -225,9 +225,14 @@ void resctrl_arch_mbm_cntr_assign_set_one(struct rdt_resource *r);
 #ifdef CONFIG_X86_CPU_RESCTRL_INTEL_AET
 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);
 #else
 static inline bool intel_aet_get_events(void) { return false; }
 static inline void __exit intel_aet_exit(void) { }
+static inline int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64 *val)
+{
+       return -EINVAL;
+}
 #endif
 
 #endif /* _ASM_X86_RESCTRL_INTERNAL_H */

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 6929614ba6e6de09a7a8b917c8476ecd6113044b..e6a154240b8d90bd735d56c1a2fa0f33b875b4ac 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -251,6 +251,10 @@ int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain_hdr *hdr,
        int ret;
 
        resctrl_arch_rmid_read_context_check();
+
+       if (r->rid == RDT_RESOURCE_PERF_PKG)
+               return intel_aet_read_event(hdr->id, rmid, arch_priv, val);
+
        if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
                return -EINVAL;
 

diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
index 9af08b673e395d0bc4d3171fc54b7e4ad9cc8959..8a4c2ae72740cf801588f9fdf1a4883335363058 100644 (file)
--- a/fs/resctrl/monitor.c
+++ b/fs/resctrl/monitor.c
@@ -527,6 +527,20 @@ static int __mon_event_count(struct rdtgroup *rdtgrp, struct rmid_read *rr)
                        return __l3_mon_event_count(rdtgrp, rr);
                else
                        return __l3_mon_event_count_sum(rdtgrp, rr);
+       case RDT_RESOURCE_PERF_PKG: {
+               u64 tval = 0;
+
+               rr->err = resctrl_arch_rmid_read(rr->r, rr->hdr, rdtgrp->closid,
+                                                rdtgrp->mon.rmid, rr->evt->evtid,
+                                                rr->evt->arch_priv,
+                                                &tval, rr->arch_mon_ctx);
+               if (rr->err)
+                       return rr->err;
+
+               rr->val += tval;
+
+               return 0;
+       }
        default:
                rr->err = -EINVAL;
                return -EINVAL;