Replace mutex with atomic value

pkg/wallet/dsbackend.go

@@ -7,6 +7,7 @@ import (
 	"reflect"
 	"strings"
 	"sync"
+	"sync/atomic"
 
 	"github.com/awnumar/memguard"
 	"github.com/filecoin-project/go-address"
@@ -50,7 +51,7 @@ type DSBackend struct {
 	password *memguard.Enclave
 	unLocked map[address.Address]*key.KeyInfo
 
-	state int
+	state atomic.Int64
 }
 
 var _ Backend = (*DSBackend)(nil)
@@ -198,11 +199,8 @@ func (backend *DSBackend) putKeyInfo(ctx context.Context, ki *key.KeyInfo) error
 	if err := backend.ds.Put(ctx, ds.NewKey(key.Address.String()), keyJSON); err != nil {
 		return errors.Wrapf(err, "failed to store new address: %s", key.Address.String())
 	}
-
-	backend.lk.Lock()
 	backend.cache[addr] = struct{}{}
 	backend.unLocked[addr] = ki
-	backend.lk.Unlock()
 	return nil
 }
 
@@ -285,9 +283,7 @@ func (backend *DSBackend) getKey(ctx context.Context, addr address.Address, pass
 }
 
 func (backend *DSBackend) LockWallet(ctx context.Context) error {
-	backend.lk.Lock()
-	defer backend.lk.Unlock()
-	if backend.state == Lock {
+	if backend.state.Load() == Lock {
 		return fmt.Errorf("already locked")
 	}
 
@@ -296,24 +292,24 @@ func (backend *DSBackend) LockWallet(ctx context.Context) error {
 	}
 
 	for _, addr := range backend.Addresses(ctx) {
+		backend.lk.Lock()
 		delete(backend.unLocked, addr)
+		backend.lk.Unlock()
 	}
 	backend.cleanPassword()
-	backend.state = Lock
+	backend.state.Store(Lock)
 
 	return nil
 }
 
 // UnLockWallet unlock wallet with password, decrypt local key in db and save to protected memory
 func (backend *DSBackend) UnLockWallet(ctx context.Context, password []byte) error {
-	backend.lk.Lock()
 	defer func() {
-		backend.lk.Unlock()
 		for i := range password {
 			password[i] = 0
 		}
 	}()
-	if backend.state == Unlock {
+	if backend.state.Load() == Unlock {
 		return fmt.Errorf("already unlocked")
 	}
 
@@ -327,17 +323,17 @@ func (backend *DSBackend) UnLockWallet(ctx context.Context, password []byte) err
 			return err
 		}
 
+		backend.lk.Lock()
 		backend.unLocked[addr] = ki
+		backend.lk.Unlock()
 	}
-	backend.state = Unlock
+	backend.state.Store(Unlock)
 
 	return nil
 }
 
 // SetPassword set password for wallet , and wallet used this password to encrypt private key
 func (backend *DSBackend) SetPassword(ctx context.Context, password []byte) error {
-	backend.lk.Lock()
-	defer backend.lk.Unlock()
 	if backend.password != nil {
 		return ErrRepeatPassword
 	}
@@ -347,13 +343,12 @@ func (backend *DSBackend) SetPassword(ctx context.Context, password []byte) erro
 		if err != nil {
 			return err
 		}
-
+		backend.lk.Lock()
 		backend.unLocked[addr] = ki
-	}
-	if backend.state == undetermined {
-		backend.state = Unlock
+		backend.lk.Unlock()
 	}
 
+	backend.state.CompareAndSwap(undetermined, Unlock)
 	backend.setPassword(password)
 
 	return nil
@@ -366,9 +361,7 @@ func (backend *DSBackend) HasPassword() bool {
 
 // WalletState return wallet state(lock/unlock)
 func (backend *DSBackend) WalletState(ctx context.Context) int {
-	backend.lk.Lock()
-	defer backend.lk.Unlock()
-	return backend.state
+	return int(backend.state.Load())
 }
 
 func (backend *DSBackend) setPassword(password []byte) {