From 2946157c6f7d8903307da737bc5a6c48172891be Mon Sep 17 00:00:00 2001
From: Oleg Zhurakivskyy <oleg.zhurakivskyy@intel.com>
Date: Sun, 18 Aug 2024 19:30:33 +0300
Subject: [PATCH] nfd-topology-updater: Detect E/P cores and expose through
 attributes

Signed-off-by: Oleg Zhurakivskyy <oleg.zhurakivskyy@intel.com>
---
 .../nfd-topology-updater.go                   | 31 +++++++++++++++++++
 source/cpu/cpu.go                             | 10 ++++++
 2 files changed, 41 insertions(+)

diff --git a/pkg/nfd-topology-updater/nfd-topology-updater.go b/pkg/nfd-topology-updater/nfd-topology-updater.go
index e65edbea2..9d625e5ee 100644
--- a/pkg/nfd-topology-updater/nfd-topology-updater.go
+++ b/pkg/nfd-topology-updater/nfd-topology-updater.go
@@ -22,6 +22,7 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"golang.org/x/net/context"
 
@@ -42,6 +43,7 @@ import (
 	"sigs.k8s.io/node-feature-discovery/pkg/resourcemonitor"
 	"sigs.k8s.io/node-feature-discovery/pkg/topologypolicy"
 	"sigs.k8s.io/node-feature-discovery/pkg/utils"
+	"sigs.k8s.io/node-feature-discovery/pkg/utils/hostpath"
 	"sigs.k8s.io/node-feature-discovery/pkg/utils/kubeconf"
 	"sigs.k8s.io/node-feature-discovery/pkg/version"
 	"sigs.k8s.io/yaml"
@@ -337,6 +339,32 @@ func (w *nfdTopologyUpdater) updateNodeResourceTopology(zoneInfo v1alpha2.ZoneLi
 	return nil
 }
 
+// Discover E/P cores
+func discoverCpuCores() v1alpha2.AttributeList {
+	attrList := v1alpha2.AttributeList{}
+
+	cpusPathGlob := hostpath.SysfsDir.Path("sys/devices/cpu_*/cpus")
+	cpuPaths, err := filepath.Glob(cpusPathGlob)
+	if err != nil {
+		klog.ErrorS(err, "error reading cpu entries", "cpusPathGlob", cpusPathGlob)
+		return attrList
+	}
+
+	for _, entry := range cpuPaths {
+		cpus, err := os.ReadFile(entry)
+		if err != nil {
+			klog.ErrorS(err, "error reading cpu entry file", "entry", entry)
+		} else {
+			attrList = append(attrList, v1alpha2.AttributeInfo{
+				Name:  filepath.Base(filepath.Dir(entry)),
+				Value: strings.TrimSpace(string(cpus)),
+			})
+		}
+	}
+
+	return attrList
+}
+
 func (w *nfdTopologyUpdater) updateNRTTopologyManagerInfo(nrt *v1alpha2.NodeResourceTopology) error {
 	policy, scope, err := w.detectTopologyPolicyAndScope()
 	if err != nil {
@@ -349,6 +377,9 @@ func (w *nfdTopologyUpdater) updateNRTTopologyManagerInfo(nrt *v1alpha2.NodeReso
 	updateAttributes(&nrt.Attributes, tmAttributes)
 	nrt.TopologyPolicies = deprecatedTopologyPolicies
 
+	attrList := discoverCpuCores()
+	updateAttributes(&nrt.Attributes, attrList)
+
 	return nil
 }
 
diff --git a/source/cpu/cpu.go b/source/cpu/cpu.go
index 8b889cd7e..1dfd8068c 100644
--- a/source/cpu/cpu.go
+++ b/source/cpu/cpu.go
@@ -198,6 +198,16 @@ func (s *cpuSource) GetLabels() (source.FeatureLabels, error) {
 		labels["coprocessor.nx_gzip"] = v
 	}
 
+	_, err := os.ReadFile(hostpath.SysfsDir.Path("sys/devices/cpu_atom/cpus"))
+	if err == nil {
+		labels["cpu_atom"] = true
+	}
+
+	_, err = os.ReadFile(hostpath.SysfsDir.Path("sys/devices/cpu_core/cpus"))
+	if err == nil {
+		labels["cpu_core"] = true
+	}
+
 	return labels, nil
 }