light: use atomic type (#27169)

* light: use atomic type

* light: use a suitable name for the stopped switch in LightChain

light/lightchain.go

@@ -70,9 +70,9 @@ type LightChain struct {
 	wg      sync.WaitGroup
 
 	// Atomic boolean switches:
-	running          int32 // whether LightChain is running or stopped
-	procInterrupt    int32 // interrupts chain insert
-	disableCheckFreq int32 // disables header verification
+	stopped          atomic.Bool // whether LightChain is stopped or running
+	procInterrupt    atomic.Bool // interrupts chain insert
+	disableCheckFreq atomic.Bool // disables header verification
 }
 
 // NewLightChain returns a fully initialised light chain using information
@@ -114,7 +114,7 @@ func NewLightChain(odr OdrBackend, config *params.ChainConfig, engine consensus.
 }
 
 func (lc *LightChain) getProcInterrupt() bool {
-	return atomic.LoadInt32(&lc.procInterrupt) == 1
+	return lc.procInterrupt.Load()
 }
 
 // Odr returns the ODR backend of the chain
@@ -302,7 +302,7 @@ func (lc *LightChain) GetBlockByNumber(ctx context.Context, number uint64) (*typ
 // Stop stops the blockchain service. If any imports are currently in progress
 // it will abort them using the procInterrupt.
 func (lc *LightChain) Stop() {
-	if !atomic.CompareAndSwapInt32(&lc.running, 0, 1) {
+	if !lc.stopped.CompareAndSwap(false, true) {
 		return
 	}
 	close(lc.quit)
@@ -315,7 +315,7 @@ func (lc *LightChain) Stop() {
 // errInsertionInterrupted as soon as possible. Insertion is permanently disabled after
 // calling this method.
 func (lc *LightChain) StopInsert() {
-	atomic.StoreInt32(&lc.procInterrupt, 1)
+	lc.procInterrupt.Store(true)
 }
 
 // Rollback is designed to remove a chain of links from the database that aren't
@@ -393,7 +393,7 @@ func (lc *LightChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (i
 	if len(chain) == 0 {
 		return 0, nil
 	}
-	if atomic.LoadInt32(&lc.disableCheckFreq) == 1 {
+	if lc.disableCheckFreq.Load() {
 		checkFreq = 0
 	}
 	start := time.Now()
@@ -541,10 +541,10 @@ func (lc *LightChain) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent)
 
 // DisableCheckFreq disables header validation. This is used for ultralight mode.
 func (lc *LightChain) DisableCheckFreq() {
-	atomic.StoreInt32(&lc.disableCheckFreq, 1)
+	lc.disableCheckFreq.Store(true)
 }
 
 // EnableCheckFreq enables header validation.
 func (lc *LightChain) EnableCheckFreq() {
-	atomic.StoreInt32(&lc.disableCheckFreq, 0)
+	lc.disableCheckFreq.Store(false)
 }