[cpu][linux] Test Counts against lscpu results

cpu/cpu_linux_test.go

@@ -2,6 +2,9 @@ package cpu
 
 import (
 	"os"
+	"os/exec"
+	"strconv"
+	"strings"
 	"testing"
 )
 
@@ -38,3 +41,53 @@ func TestCPUparseStatLine_424(t *testing.T) {
 	}
 	os.Setenv("HOST_PROC", orig)
 }
+
+func TestCPUCountsAgainstLscpu(t *testing.T) {
+	lscpu, err := exec.LookPath("lscpu")
+	if err != nil {
+		t.Skip("no lscpu to compare with")
+	}
+	cmd := exec.Command(lscpu)
+	cmd.Env = []string{"LC_ALL=C"}
+	out, err := cmd.Output()
+	if err != nil {
+		t.Errorf("error executing lscpu: %v", err)
+	}
+	var threadsPerCore, coresPerSocket, sockets int
+	lines := strings.Split(string(out), "\n")
+	for _, line := range lines {
+		fields := strings.Split(line, ":")
+		if len(fields) < 2 {
+			continue
+		}
+		switch fields[0] {
+		case "Thread(s) per core":
+			threadsPerCore, _ = strconv.Atoi(strings.TrimSpace(fields[1]))
+		case "Core(s) per socket":
+			coresPerSocket, _ = strconv.Atoi(strings.TrimSpace(fields[1]))
+		case "Socket(s)":
+			sockets, _ = strconv.Atoi(strings.TrimSpace(fields[1]))
+		}
+	}
+	if threadsPerCore == 0 || coresPerSocket == 0 || sockets == 0 {
+		t.Errorf("missing info from lscpu: threadsPerCore=%d coresPerSocket=%d sockets=%d", threadsPerCore, coresPerSocket, sockets)
+	}
+	expectedPhysical := coresPerSocket * sockets
+	expectedLogical := expectedPhysical * threadsPerCore
+	physical, err := Counts(false)
+	skipIfNotImplementedErr(t, err)
+	if err != nil {
+		t.Errorf("error %v", err)
+	}
+	logical, err := Counts(true)
+	skipIfNotImplementedErr(t, err)
+	if err != nil {
+		t.Errorf("error %v", err)
+	}
+	if expectedPhysical != physical {
+		t.Errorf("expected %v, got %v", expectedPhysical, physical)
+	}
+	if expectedLogical != logical {
+		t.Errorf("expected %v, got %v", expectedLogical, logical)
+	}
+}