Merge pull request #74016 from ahadas/topology_cleanup

Cleanup in topology.go

pkg/kubelet/cm/cpumanager/topology/topology.go

@@ -18,7 +18,6 @@ package topology
 
 import (
 	"fmt"
-	"sort"
 
 	cadvisorapi "github.com/google/cadvisor/info/v1"
 	"k8s.io/klog"
@@ -141,36 +140,33 @@ func (d CPUDetails) CPUsInCore(id int) cpuset.CPUSet {
 
 // Discover returns CPUTopology based on cadvisor node info
 func Discover(machineInfo *cadvisorapi.MachineInfo) (*CPUTopology, error) {
-
 	if machineInfo.NumCores == 0 {
 		return nil, fmt.Errorf("could not detect number of cpus")
 	}
 
 	CPUDetails := CPUDetails{}
-	numCPUs := machineInfo.NumCores
 	numPhysicalCores := 0
-	var coreID int
-	var err error
 
 	for _, socket := range machineInfo.Topology {
 		numPhysicalCores += len(socket.Cores)
 		for _, core := range socket.Cores {
-			if coreID, err = getUniqueCoreID(core.Threads); err != nil {
+			if coreID, err := getUniqueCoreID(core.Threads); err == nil {
+				for _, cpu := range core.Threads {
+					CPUDetails[cpu] = CPUInfo{
+						CoreID:   coreID,
+						SocketID: socket.Id,
+					}
+				}
+			} else {
 				klog.Errorf("could not get unique coreID for socket: %d core %d threads: %v",
 					socket.Id, core.Id, core.Threads)
 				return nil, err
 			}
-			for _, cpu := range core.Threads {
-				CPUDetails[cpu] = CPUInfo{
-					CoreID:   coreID,
-					SocketID: socket.Id,
-				}
-			}
 		}
 	}
 
 	return &CPUTopology{
-		NumCPUs:    numCPUs,
+		NumCPUs:    machineInfo.NumCores,
 		NumSockets: len(machineInfo.Topology),
 		NumCores:   numPhysicalCores,
 		CPUDetails: CPUDetails,
@@ -181,7 +177,6 @@ func Discover(machineInfo *cadvisorapi.MachineInfo) (*CPUTopology, error) {
 // for a given Threads []int slice. This will assure that coreID's are
 // platform unique (opposite to what cAdvisor reports - socket unique)
 func getUniqueCoreID(threads []int) (coreID int, err error) {
-	err = nil
 	if len(threads) == 0 {
 		return 0, fmt.Errorf("no cpus provided")
 	}
@@ -190,8 +185,12 @@ func getUniqueCoreID(threads []int) (coreID int, err error) {
 		return 0, fmt.Errorf("cpus provided are not unique")
 	}
 
-	tmpThreads := make([]int, len(threads))
-	copy(tmpThreads, threads)
-	sort.Ints(tmpThreads)
-	return tmpThreads[0], err
+	min := threads[0]
+	for _, thread := range threads[1:] {
+		if thread < min {
+			min = thread
+		}
+	}
+
+	return min, nil
 }