revert additional locking in hashdb/Database.Cap

trie/triedb/hashdb/database.go

@@ -331,23 +331,19 @@ func (db *Database) Cap(limit common.StorageSize) error {
 	// by only uncaching existing data when the database write finalizes.
 	start := time.Now()
 	batch := db.diskdb.NewBatch()
-	db.lock.RLock()
 	nodes, storage := len(db.dirties), db.dirtiesSize
 
 	// db.dirtiesSize only contains the useful data in the cache, but when reporting
 	// the total memory consumption, the maintenance metadata is also needed to be
 	// counted.
 	size := db.dirtiesSize + common.StorageSize(len(db.dirties)*cachedNodeSize)
 	size += db.childrenSize
-	db.lock.RUnlock()
 
 	// Keep committing nodes from the flush-list until we're below allowance
 	oldest := db.oldest
 	for size > limit && oldest != (common.Hash{}) {
 		// Fetch the oldest referenced node and push into the batch
-		db.lock.RLock()
 		node := db.dirties[oldest]
-		db.lock.RUnlock()
 		rawdb.WriteLegacyTrieNode(batch, oldest, node.node)
 
 		// If we exceeded the ideal batch size, commit and reset