chore: Apply comments

baseapp/abci.go

@@ -366,9 +366,6 @@ func (app *BaseApp) CheckTxSync(req *abci.RequestCheckTx) (*abci.ResponseCheckTx
 	return &abci.ResponseCheckTx{
 		GasWanted: int64(gInfo.GasWanted), // TODO: Should type accept unsigned ints?
 		GasUsed:   int64(gInfo.GasUsed),   // TODO: Should type accept unsigned ints?
-		// Log:       result.Log,
-		// Data:      result.Data,
-		// Events:    sdk.MarkEventsToIndex(result.Events, app.indexEvents),
 	}, nil
 }
 

baseapp/accountwgs.go

@@ -18,15 +18,29 @@ func NewAccountWGs() *AccountWGs {
 	}
 }
 
+// Register registers transaction signers and returns necessary WaitGroups.
+// It ensures that transactions from the same signer are processed sequentially.
+//
+// Parameters:
+// - cdc: Codec for decoding transaction messages
+// - tx: Transaction to be registered
+//
+// Returns:
+// - waits: WaitGroups that need to be waited on (from previous transactions of the same signers)
+// - signals: WaitGroups that should be signaled when this transaction completes
 func (aw *AccountWGs) Register(cdc codec.Codec, tx sdk.Tx) (waits []*sync.WaitGroup, signals []*AccountWG) {
+	// Get unique signers from the tx
 	signers := getUniqSigners(cdc, tx)
 
 	aw.mtx.Lock()
 	defer aw.mtx.Unlock()
 	for _, signer := range signers {
+		// If there's an existing WaitGroup for this signer,
+		// we need to wait for it before processing the current transaction
 		if wg := aw.wgs[signer]; wg != nil {
 			waits = append(waits, wg)
 		}
+		// Create a new WaitGroup for the current transaction
 		sig := waitGroup1()
 		aw.wgs[signer] = sig
 		signals = append(signals, NewAccountWG(signer, sig))

baseapp/baseapp.go

@@ -520,6 +520,11 @@ func (app *BaseApp) setState(mode execMode, h cmtproto.Header) {
 
 	switch mode {
 	case execModeCheck:
+		// Acquire a lock to ensure thread-safe access to `checkState` during state updates.
+		// Since `CheckTxAsync` runs checkTx concurrently, this lock is necessary to
+		// prevent data races and ensure that updates to `checkState` remain consistent
+		// across all goroutines. Without this lock, concurrent modifications could
+		// lead to inconsistent application states or runtime errors.
 		app.checkStateMtx.Lock()
 		defer app.checkStateMtx.Unlock()
 		baseState.SetContext(baseState.Context().WithIsCheckTx(true).WithMinGasPrices(app.minGasPrices))
@@ -690,6 +695,10 @@ func (app *BaseApp) getBlockGasMeter(ctx sdk.Context) storetypes.GasMeter {
 // retrieve the context for the tx w/ txBytes and other memoized values.
 func (app *BaseApp) getContextForTx(mode execMode, txBytes []byte, txIndex int) sdk.Context {
 	if mode == execModeCheck || mode == execModeReCheck {
+		// By introducing Parallel CheckTx, now getContextForTx can be called by multiple goroutines.
+		// Without this lock, multiple goroutines could attempt to modify or read `checkState` simultaneously,
+		// leading to inconsistent or corrupted state.
+		// The lock guarantees a consistent context is maintained across all CheckTx operations.
 		app.checkStateMtx.Lock()
 		defer app.checkStateMtx.Unlock()
 	}