Feature cleanup: Removing unwanted rounding in fee calculation #21 (#4676)

cleanup activated feature: Removing unwanted rounding in fee calculation #21

fee/src/lib.rs

@@ -1,7 +1,5 @@
 use {
-    solana_feature_set::{
-        enable_secp256r1_precompile, remove_rounding_in_fee_calculation, FeatureSet,
-    },
+    solana_feature_set::{enable_secp256r1_precompile, FeatureSet},
     solana_fee_structure::FeeDetails,
     solana_svm_transaction::svm_message::SVMMessage,
 };
@@ -14,15 +12,12 @@ use {
 // in the future. Keeping this struct will help keep things organized.
 #[derive(Copy, Clone)]
 pub struct FeeFeatures {
-    pub remove_rounding_in_fee_calculation: bool,
     pub enable_secp256r1_precompile: bool,
 }
 
 impl From<&FeatureSet> for FeeFeatures {
     fn from(feature_set: &FeatureSet) -> Self {
         Self {
-            remove_rounding_in_fee_calculation: feature_set
-                .is_active(&remove_rounding_in_fee_calculation::ID),
             enable_secp256r1_precompile: feature_set.is_active(&enable_secp256r1_precompile::ID),
         }
     }
@@ -64,7 +59,6 @@ pub fn calculate_fee_details(
             fee_features.enable_secp256r1_precompile,
         ),
         prioritization_fee,
-        fee_features.remove_rounding_in_fee_calculation,
     )
 }
 

runtime/src/bank/tests.rs

@@ -3044,7 +3044,7 @@ fn test_filter_program_errors_and_collect_fee() {
     bank.deactivate_feature(&feature_set::reward_full_priority_fee::id());
 
     let tx_fee = 42;
-    let fee_details = FeeDetails::new(tx_fee, 0, false);
+    let fee_details = FeeDetails::new(tx_fee, 0);
     let processing_results = vec![
         Err(TransactionError::AccountNotFound),
         new_executed_processing_result(Ok(()), fee_details),
@@ -3083,7 +3083,7 @@ fn test_filter_program_errors_and_collect_priority_fee() {
     bank.deactivate_feature(&feature_set::reward_full_priority_fee::id());
 
     let priority_fee = 42;
-    let fee_details: FeeDetails = FeeDetails::new(0, priority_fee, false);
+    let fee_details: FeeDetails = FeeDetails::new(0, priority_fee);
     let processing_results = vec![
         Err(TransactionError::AccountNotFound),
         new_executed_processing_result(Ok(()), fee_details),
@@ -3344,7 +3344,7 @@ fn test_load_and_execute_commit_transactions_fees_only(enable_fees_only_txs: boo
                 inner_instructions: None,
                 return_data: None,
                 executed_units: 0,
-                fee_details: FeeDetails::new(5000, 0, true),
+                fee_details: FeeDetails::new(5000, 0),
                 rent_debits: RentDebits::default(),
                 loaded_account_stats: TransactionLoadedAccountsStats {
                     loaded_accounts_count: 2,
@@ -10392,7 +10392,6 @@ fn calculate_test_fee(
         fee_structure.lamports_per_signature,
         fee_budget_limits.prioritization_fee,
         FeeFeatures {
-            remove_rounding_in_fee_calculation: true,
             enable_secp256r1_precompile: true,
         },
     )
@@ -13234,7 +13233,7 @@ fn test_filter_program_errors_and_collect_fee_details() {
     let initial_payer_balance = 7_000;
     let tx_fee = 5000;
     let priority_fee = 1000;
-    let fee_details = FeeDetails::new(tx_fee, priority_fee, false);
+    let fee_details = FeeDetails::new(tx_fee, priority_fee);
     let expected_collected_fee_details = CollectorFeeDetails {
         transaction_fee: 3 * tx_fee,
         priority_fee: 3 * priority_fee,

sdk/fee-structure/src/lib.rs

@@ -41,30 +41,18 @@ pub struct FeeStructure {
 pub struct FeeDetails {
     transaction_fee: u64,
     prioritization_fee: u64,
-    remove_rounding_in_fee_calculation: bool,
 }
 
 impl FeeDetails {
-    pub fn new(
-        transaction_fee: u64,
-        prioritization_fee: u64,
-        remove_rounding_in_fee_calculation: bool,
-    ) -> Self {
+    pub fn new(transaction_fee: u64, prioritization_fee: u64) -> Self {
         Self {
             transaction_fee,
             prioritization_fee,
-            remove_rounding_in_fee_calculation,
         }
     }
 
     pub fn total_fee(&self) -> u64 {
-        let total_fee = self.transaction_fee.saturating_add(self.prioritization_fee);
-        if self.remove_rounding_in_fee_calculation {
-            total_fee
-        } else {
-            // backward compatible behavior
-            (total_fee as f64).round() as u64
-        }
+        self.transaction_fee.saturating_add(self.prioritization_fee)
     }
 
     pub fn accumulate(&mut self, fee_details: &FeeDetails) {
@@ -141,7 +129,6 @@ impl FeeStructure {
         lamports_per_signature: u64,
         budget_limits: &FeeBudgetLimits,
         include_loaded_account_data_size_in_fee: bool,
-        remove_rounding_in_fee_calculation: bool,
     ) -> u64 {
         #[allow(deprecated)]
         self.calculate_fee_details(
@@ -149,7 +136,6 @@ impl FeeStructure {
             lamports_per_signature,
             budget_limits,
             include_loaded_account_data_size_in_fee,
-            remove_rounding_in_fee_calculation,
         )
         .total_fee()
     }
@@ -166,7 +152,6 @@ impl FeeStructure {
         lamports_per_signature: u64,
         budget_limits: &FeeBudgetLimits,
         include_loaded_account_data_size_in_fee: bool,
-        remove_rounding_in_fee_calculation: bool,
     ) -> FeeDetails {
         // Backward compatibility - lamports_per_signature == 0 means to clear
         // transaction fee to zero
@@ -210,7 +195,6 @@ impl FeeStructure {
                 .saturating_add(write_lock_fee)
                 .saturating_add(compute_fee),
             prioritization_fee: budget_limits.prioritization_fee,
-            remove_rounding_in_fee_calculation,
         }
     }
 }
@@ -263,28 +247,4 @@ mod tests {
             FeeStructure::calculate_memory_usage_cost(64 * K, heap_cost)
         );
     }
-
-    #[test]
-    fn test_total_fee_rounding() {
-        // round large `f64` can lost precision, see feature gate:
-        // "Removing unwanted rounding in fee calculation #34982"
-
-        let transaction_fee = u64::MAX - 11;
-        let prioritization_fee = 1;
-        let expected_large_fee = u64::MAX - 10;
-
-        let details_with_rounding = FeeDetails {
-            transaction_fee,
-            prioritization_fee,
-            remove_rounding_in_fee_calculation: false,
-        };
-        let details_without_rounding = FeeDetails {
-            transaction_fee,
-            prioritization_fee,
-            remove_rounding_in_fee_calculation: true,
-        };
-
-        assert_eq!(details_without_rounding.total_fee(), expected_large_fee);
-        assert_ne!(details_with_rounding.total_fee(), expected_large_fee);
-    }
 }

svm/src/transaction_processor.rs

@@ -2194,7 +2194,7 @@ mod tests {
                     fee_payer_rent_epoch
                 ),
                 compute_budget_limits,
-                fee_details: FeeDetails::new(transaction_fee, priority_fee, false),
+                fee_details: FeeDetails::new(transaction_fee, priority_fee),
                 loaded_fee_payer_account: LoadedTransactionAccount {
                     loaded_size: fee_payer_account.data().len(),
                     account: post_validation_fee_payer_account,
@@ -2271,7 +2271,7 @@ mod tests {
                     0, // rent epoch
                 ),
                 compute_budget_limits,
-                fee_details: FeeDetails::new(transaction_fee, 0, false),
+                fee_details: FeeDetails::new(transaction_fee, 0),
                 loaded_fee_payer_account: LoadedTransactionAccount {
                     loaded_size: fee_payer_account.data().len(),
                     account: post_validation_fee_payer_account,
@@ -2520,7 +2520,7 @@ mod tests {
                         0, // fee_payer_rent_epoch
                     ),
                     compute_budget_limits,
-                    fee_details: FeeDetails::new(transaction_fee, priority_fee, false),
+                    fee_details: FeeDetails::new(transaction_fee, priority_fee),
                     loaded_fee_payer_account: LoadedTransactionAccount {
                         loaded_size: fee_payer_account.data().len(),
                         account: post_validation_fee_payer_account,