fix access logger high cpu usage, simplify some code

internal/utils/ref_count.go

@@ -1,15 +1,12 @@
 package utils
 
 import (
-	"sync"
 	"sync/atomic"
 )
 
 type RefCount struct {
 	_ NoCopy
 
-	mu       sync.Mutex
-	cond     *sync.Cond
 	refCount uint32
 	zeroCh   chan struct{}
 }
@@ -19,7 +16,6 @@ func NewRefCounter() *RefCount {
 		refCount: 1,
 		zeroCh:   make(chan struct{}),
 	}
-	rc.cond = sync.NewCond(&rc.mu)
 	return rc
 }
 
@@ -33,9 +29,6 @@ func (rc *RefCount) Add() {
 
 func (rc *RefCount) Sub() {
 	if atomic.AddUint32(&rc.refCount, ^uint32(0)) == 0 {
-		rc.mu.Lock()
 		close(rc.zeroCh)
-		rc.cond.Broadcast()
-		rc.mu.Unlock()
 	}
 }