tidy comments

internal/common/common_windows.go

@@ -94,7 +94,7 @@ func BytePtrToString(p *uint8) string {
 	return string(a[:i])
 }
 
-// CounterInfo XXX
+// CounterInfo struct is used to track a windows performance counter
 // copied from https://github.com/mackerelio/mackerel-agent/
 type CounterInfo struct {
 	PostName    string
@@ -102,7 +102,7 @@ type CounterInfo struct {
 	Counter     windows.Handle
 }
 
-// CreateQuery XXX
+// CreateQuery with a PdhOpenQuery call
 // copied from https://github.com/mackerelio/mackerel-agent/
 func CreateQuery() (windows.Handle, error) {
 	var query windows.Handle
@@ -113,7 +113,7 @@ func CreateQuery() (windows.Handle, error) {
 	return query, nil
 }
 
-// CreateCounter XXX
+// CreateCounter with a PdhAddCounter call
 func CreateCounter(query windows.Handle, pname, cname string) (*CounterInfo, error) {
 	var counter windows.Handle
 	r, _, err := PdhAddCounter.Call(

load/load_windows.go

@@ -22,9 +22,9 @@ var (
 )
 
 // loadAvgGoroutine updates avg data by fetching current load by interval
-// TODO register callback rather than this
+// TODO instead of this goroutine, we can register a Win32 counter just as psutil does
 // see https://psutil.readthedocs.io/en/latest/#psutil.getloadavg
-// code https://github.com/giampaolo/psutil/blob/master/psutil/arch/windows/wmi.c
+// code https://github.com/giampaolo/psutil/blob/8415355c8badc9c94418b19bdf26e622f06f0cce/psutil/arch/windows/wmi.c
 func loadAvgGoroutine() {
 	const (
 		loadAvgFactor1F  = 0.9200444146293232478931553241