core/state: colocate StateCounts/ReadDurations with StateDB

Moves the snapshot DTOs into statedb.go directly above SnapshotCounts
and SnapshotReads, so the types and their sole constructors live in the
same file. Avoids a single-purpose state_counts.go.

core/state/state_counts.go

@@ -1,69 +0,0 @@
-// Copyright 2026 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package state
-
-import "time"
-
-// ReadDurations groups the {Account, Storage, Code} state-read times that are
-// aggregated across pre-tx, per-tx and post-tx statedbs in the BAL parallel
-// path. Sum-of-CPU-time, not wall-clock.
-type ReadDurations struct {
-	Account time.Duration
-	Storage time.Duration
-	Code    time.Duration
-}
-
-// Add merges other into r.
-func (r *ReadDurations) Add(other ReadDurations) {
-	r.Account += other.Account
-	r.Storage += other.Storage
-	r.Code += other.Code
-}
-
-// StateCounts holds count-only statistics gathered during a block's state
-// transition. Plain-int snapshot type, safe to copy through channels.
-// Atomic counters on StateDB are converted at the snapshot boundary in
-// SnapshotCounts. Read durations live in ReadDurations (separate type).
-type StateCounts struct {
-	AccountLoaded   int   // accounts retrieved from the database during the state transition
-	AccountUpdated  int   // accounts updated during the state transition
-	AccountDeleted  int   // accounts deleted during the state transition
-	StorageLoaded   int   // storage slots retrieved from the database during the state transition
-	StorageUpdated  int64 // storage slots updated (snapshotted from atomic on StateDB)
-	StorageDeleted  int64 // storage slots deleted (snapshotted from atomic on StateDB)
-	CodeLoaded      int   // contract code reads
-	CodeLoadBytes   int   // total bytes of resolved code
-	CodeUpdated     int   // code writes (CREATE/CREATE2/EIP-7702)
-	CodeUpdateBytes int   // total bytes of persisted code written
-}
-
-// Add merges other into c. Plain integer addition — no atomics here, since
-// StateCounts is the snapshot type. The receiver is the only mutated party;
-// other is taken by value (the struct is small and value semantics matches
-// the snapshot thesis stated above).
-func (c *StateCounts) Add(other StateCounts) {
-	c.AccountLoaded += other.AccountLoaded
-	c.AccountUpdated += other.AccountUpdated
-	c.AccountDeleted += other.AccountDeleted
-	c.StorageLoaded += other.StorageLoaded
-	c.StorageUpdated += other.StorageUpdated
-	c.StorageDeleted += other.StorageDeleted
-	c.CodeLoaded += other.CodeLoaded
-	c.CodeLoadBytes += other.CodeLoadBytes
-	c.CodeUpdated += other.CodeUpdated
-	c.CodeUpdateBytes += other.CodeUpdateBytes
-}

core/state/statedb.go

@@ -223,6 +223,56 @@ func (s *StateDB) WithReader(reader Reader) *StateDB {
 	return cpy
 }
 
+// ReadDurations groups the {Account, Storage, Code} state-read times that are
+// aggregated across pre-tx, per-tx and post-tx statedbs in the BAL parallel
+// path. Sum-of-CPU-time, not wall-clock.
+type ReadDurations struct {
+	Account time.Duration
+	Storage time.Duration
+	Code    time.Duration
+}
+
+// Add merges other into r.
+func (r *ReadDurations) Add(other ReadDurations) {
+	r.Account += other.Account
+	r.Storage += other.Storage
+	r.Code += other.Code
+}
+
+// StateCounts holds count-only statistics gathered during a block's state
+// transition. Plain-int snapshot type, safe to copy through channels.
+// Atomic counters on StateDB are converted at the snapshot boundary in
+// SnapshotCounts. Read durations live in ReadDurations (separate type).
+type StateCounts struct {
+	AccountLoaded   int   // accounts retrieved from the database during the state transition
+	AccountUpdated  int   // accounts updated during the state transition
+	AccountDeleted  int   // accounts deleted during the state transition
+	StorageLoaded   int   // storage slots retrieved from the database during the state transition
+	StorageUpdated  int64 // storage slots updated (snapshotted from atomic on StateDB)
+	StorageDeleted  int64 // storage slots deleted (snapshotted from atomic on StateDB)
+	CodeLoaded      int   // contract code reads
+	CodeLoadBytes   int   // total bytes of resolved code
+	CodeUpdated     int   // code writes (CREATE/CREATE2/EIP-7702)
+	CodeUpdateBytes int   // total bytes of persisted code written
+}
+
+// Add merges other into c. Plain integer addition — no atomics here, since
+// StateCounts is the snapshot type. The receiver is the only mutated party;
+// other is taken by value (the struct is small and value semantics matches
+// the snapshot thesis stated above).
+func (c *StateCounts) Add(other StateCounts) {
+	c.AccountLoaded += other.AccountLoaded
+	c.AccountUpdated += other.AccountUpdated
+	c.AccountDeleted += other.AccountDeleted
+	c.StorageLoaded += other.StorageLoaded
+	c.StorageUpdated += other.StorageUpdated
+	c.StorageDeleted += other.StorageDeleted
+	c.CodeLoaded += other.CodeLoaded
+	c.CodeLoadBytes += other.CodeLoadBytes
+	c.CodeUpdated += other.CodeUpdated
+	c.CodeUpdateBytes += other.CodeUpdateBytes
+}
+
 // SnapshotCounts returns a value-copy of the state-mutation counters as a
 // plain-int StateCounts. Atomic fields are read via Load(); the result is
 // safe to copy, pass through channels, and aggregate via StateCounts.Add.