core: split BAL read-time access from cached metrics struct

Replace the cached AccountReadTime/StorageReadTime fields (which had a
snapshot-staleness bug fixed in 16e98f5d9 by re-calling Metrics()) with
a live ReadTimes() accessor. Metrics() now only returns commit/hash-phase
timings — it no longer touches atomics. blockchain.go reads atomics
directly via stateTransition.ReadTimes(), eliminating the refresh hack.

Also resolves the I1 fragility: Metrics() returning &s.metrics no longer
involves any writes inside the function, so concurrent callers can't race
on the read-time field updates.

core/blockchain.go

@@ -677,10 +677,6 @@ func (bc *BlockChain) processBlockWithAccessList(parentRoot common.Hash, block *
 		stats.DatabaseCommit = m.TrieDBCommits
 		stats.Prefetch = m.StatePrefetch
 	}
-	// Refresh BAL read-time cache: commitAccount runs storage reads during
-	// writeBlockWithState, after the first Metrics() snapshot.
-	stateTransition.Metrics()
-
 	// Sum read times across per-tx execution, BAL state-transition, and
 	// prefetcher async fetches. Sum-of-CPU-time, not wall-clock.
 	if w, ok := prefetchReader.(interface{ WaitPrefetch() }); ok {
@@ -692,13 +688,10 @@ func (bc *BlockChain) processBlockWithAccessList(parentRoot common.Hash, block *
 	}); ok {
 		prefetchAccountReads, prefetchStorageReads = pr.PrefetchReadTimes()
 	}
-	stats.AccountReads = res.PerTxAccountReads + prefetchAccountReads
+	balAccountReads, balStorageReads := stateTransition.ReadTimes()
-	stats.StorageReads = res.PerTxStorageReads + prefetchStorageReads
+	stats.AccountReads = res.PerTxAccountReads + prefetchAccountReads + balAccountReads
+	stats.StorageReads = res.PerTxStorageReads + prefetchStorageReads + balStorageReads
 	stats.CodeReads = res.PerTxCodeReads
-	if m := res.StateTransitionMetrics; m != nil {
-		stats.AccountReads += m.AccountReadTime
-		stats.StorageReads += m.StorageReadTime
-	}
 
 	// Cache stats from the shared prefetch reader (accumulates centrally).
 	if r, ok := prefetchReader.(state.ReaderStater); ok {

core/state/bal_state_transition.go

@@ -64,12 +64,20 @@ type BALStateTransition struct {
 	err error
 }
 
+// Metrics returns the cached commit/hash-phase timings. Read-time atomics
+// are exposed separately via ReadTimes; that decoupling avoids the
+// snapshot-staleness pitfall when commitAccount runs more reads after
+// Metrics is first called.
 func (s *BALStateTransition) Metrics() *BALStateTransitionMetrics {
-	s.metrics.AccountReadTime = time.Duration(s.accountReadNS.Load())
-	s.metrics.StorageReadTime = time.Duration(s.storageReadNS.Load())
 	return &s.metrics
 }
 
+// ReadTimes returns the current accumulated read times from atomic counters.
+// Always live; safe to call at any point after IntermediateRoot/Commit work.
+func (s *BALStateTransition) ReadTimes() (account, storage time.Duration) {
+	return time.Duration(s.accountReadNS.Load()), time.Duration(s.storageReadNS.Load())
+}
+
 // WriteCounts returns the state-mutation counts tracked during the parallel
 // state-root computation.
 func (s *BALStateTransition) WriteCounts() StateCounts {
@@ -96,11 +104,6 @@ type BALStateTransitionMetrics struct {
 	SnapshotCommits time.Duration
 	TrieDBCommits   time.Duration
 	TotalCommitTime time.Duration
-
-	// State-root recomputation read times. Sum of CPU time across the per-
-	// address goroutines that call s.reader.Account/Storage during commit.
-	AccountReadTime time.Duration
-	StorageReadTime time.Duration
 }
 
 func NewBALStateTransition(block *types.Block, prefetchReader Reader, db Database, parentRoot common.Hash) (*BALStateTransition, error) {