Only read /proc/stat once when cpu.Times(true) is called on Linux

cpu/cpu_linux.go

@@ -33,18 +33,15 @@ func Times(percpu bool) ([]TimesStat, error) {
 	filename := common.HostProc("stat")
 	var lines = []string{}
 	if percpu {
-		var startIdx uint = 1
-		for {
-			linen, _ := common.ReadLinesOffsetN(filename, startIdx, 1)
-			if len(linen) == 0 {
-				break
-			}
-			line := linen[0]
+		statlines, err := common.ReadLines(filename)
+		if err != nil || len(statlines) < 2 {
+			return []TimesStat{}, nil
+		}
+		for _, line := range statlines[1:] {
 			if !strings.HasPrefix(line, "cpu") {
 				break
 			}
 			lines = append(lines, line)
-			startIdx++
 		}
 	} else {
 		lines, _ = common.ReadLinesOffsetN(filename, 0, 1)