core/state: fix read-meters + simplify code (ethereum#24304)

core/state/state_object.go

@@ -198,25 +198,10 @@ func (s *stateObject) GetCommittedState(db Database, key common.Hash) common.Has
 	}
 	// If no live objects are available, attempt to use snapshots
 	var (
-		enc   []byte
-		err   error
-		meter *time.Duration
+		enc []byte
+		err error
 	)
-	readStart := time.Now()
-	if metrics.EnabledExpensive {
-		// If the snap is 'under construction', the first lookup may fail. If that
-		// happens, we don't want to double-count the time elapsed. Thus this
-		// dance with the metering.
-		defer func() {
-			if meter != nil {
-				*meter += time.Since(readStart)
-			}
-		}()
-	}
 	if s.db.snap != nil {
-		if metrics.EnabledExpensive {
-			meter = &s.db.SnapshotStorageReads
-		}
 		// If the object was destructed in *this* block (and potentially resurrected),
 		// the storage has been cleared out, and we should *not* consult the previous
 		// snapshot about any storage values. The only possible alternatives are:
@@ -226,20 +211,20 @@ func (s *stateObject) GetCommittedState(db Database, key common.Hash) common.Has
 		if _, destructed := s.db.snapDestructs[s.addrHash]; destructed {
 			return common.Hash{}
 		}
+		start := time.Now()
 		enc, err = s.db.snap.Storage(s.addrHash, crypto.Keccak256Hash(key.Bytes()))
+		if metrics.EnabledExpensive {
+			s.db.SnapshotStorageReads += time.Since(start)
+		}
 	}
 	// If the snapshot is unavailable or reading from it fails, load from the database.
 	if s.db.snap == nil || err != nil {
-		if meter != nil {
-			// If we already spent time checking the snapshot, account for it
-			// and reset the readStart
-			*meter += time.Since(readStart)
-			readStart = time.Now()
-		}
+		start := time.Now()
+		enc, err = s.getTrie(db).TryGet(key.Bytes())
 		if metrics.EnabledExpensive {
-			meter = &s.db.StorageReads
+			s.db.StorageReads += time.Since(start)
 		}
-		if enc, err = s.getTrie(db).TryGet(key.Bytes()); err != nil {
+		if err != nil {
 			s.setError(err)
 			return common.Hash{}
 		}

core/state/statedb.go

@@ -506,16 +506,14 @@ func (s *StateDB) getDeletedStateObject(addr common.Address) *stateObject {
 		return obj
 	}
 	// If no live objects are available, attempt to use snapshots
-	var (
-		data *types.StateAccount
-		err  error
-	)
+	var data *types.StateAccount
 	if s.snap != nil {
+		start := time.Now()
+		acc, err := s.snap.Account(crypto.HashData(s.hasher, addr.Bytes()))
 		if metrics.EnabledExpensive {
-			defer func(start time.Time) { s.SnapshotAccountReads += time.Since(start) }(time.Now())
+			s.SnapshotAccountReads += time.Since(start)
 		}
-		var acc *snapshot.Account
-		if acc, err = s.snap.Account(crypto.HashData(s.hasher, addr.Bytes())); err == nil {
+		if err == nil {
 			if acc == nil {
 				return nil
 			}
@@ -534,11 +532,12 @@ func (s *StateDB) getDeletedStateObject(addr common.Address) *stateObject {
 		}
 	}
 	// If snapshot unavailable or reading from it failed, load from the database
-	if s.snap == nil || err != nil {
+	if data == nil {
+		start := time.Now()
+		enc, err := s.trie.TryGet(addr.Bytes())
 		if metrics.EnabledExpensive {
-			defer func(start time.Time) { s.AccountReads += time.Since(start) }(time.Now())
+			s.AccountReads += time.Since(start)
 		}
-		enc, err := s.trie.TryGet(addr.Bytes())
 		if err != nil {
 			s.setError(fmt.Errorf("getDeleteStateObject (%x) error: %v", addr.Bytes(), err))
 			return nil