removes feature gate code preserving rent_epoch for rent exempt accounts (#28507)

* removes feature gate code preserving rent_epoch for rent exempt accounts

* update test expected hashes

Co-authored-by: jeff washington <jeff.washington@solana.com>

runtime/src/accounts.rs

@@ -33,7 +33,7 @@ use {
         account::{Account, AccountSharedData, ReadableAccount, WritableAccount},
         account_utils::StateMut,
         bpf_loader_upgradeable::{self, UpgradeableLoaderState},
-        clock::{BankId, Slot, INITIAL_RENT_EPOCH},
+        clock::{BankId, Slot},
         feature_set::{
             self, remove_deprecated_request_unit_ix, use_default_units_in_fee_calculation,
             FeatureSet,
@@ -272,8 +272,6 @@ impl Accounts {
             let mut accounts = Vec::with_capacity(account_keys.len());
             let mut account_deps = Vec::with_capacity(account_keys.len());
             let mut rent_debits = RentDebits::default();
-            let preserve_rent_epoch_for_rent_exempt_accounts = feature_set
-                .is_active(&feature_set::preserve_rent_epoch_for_rent_exempt_accounts::id());
             for (i, key) in account_keys.iter().enumerate() {
                 let account = if !message.is_non_loader_key(i) {
                     // Fill in an empty account for the program slots.
@@ -301,7 +299,6 @@ impl Accounts {
                                                 key,
                                                 &mut account,
                                                 self.accounts_db.filler_account_suffix.as_ref(),
-                                                preserve_rent_epoch_for_rent_exempt_accounts,
                                             )
                                             .rent_amount;
                                         (account, rent_due)
@@ -1210,7 +1207,6 @@ impl Accounts {
         rent_collector: &RentCollector,
         durable_nonce: &DurableNonce,
         lamports_per_signature: u64,
-        preserve_rent_epoch_for_rent_exempt_accounts: bool,
         include_slot_in_hash: IncludeSlotInHash,
     ) {
         let (accounts_to_store, txn_signatures) = self.collect_accounts_to_store(
@@ -1220,7 +1216,6 @@ impl Accounts {
             rent_collector,
             durable_nonce,
             lamports_per_signature,
-            preserve_rent_epoch_for_rent_exempt_accounts,
         );
         self.accounts_db.store_cached(
             (slot, &accounts_to_store[..], include_slot_in_hash),
@@ -1246,10 +1241,9 @@ impl Accounts {
         txs: &'a [SanitizedTransaction],
         execution_results: &'a [TransactionExecutionResult],
         load_results: &'a mut [TransactionLoadResult],
-        rent_collector: &RentCollector,
+        _rent_collector: &RentCollector,
         durable_nonce: &DurableNonce,
         lamports_per_signature: u64,
-        preserve_rent_epoch_for_rent_exempt_accounts: bool,
     ) -> (
         Vec<(&'a Pubkey, &'a AccountSharedData)>,
         Vec<Option<&'a Signature>>,
@@ -1303,24 +1297,6 @@ impl Accounts {
                     );
 
                     if execution_status.is_ok() || is_nonce_account || is_fee_payer {
-                        if !preserve_rent_epoch_for_rent_exempt_accounts
-                            && account.rent_epoch() == INITIAL_RENT_EPOCH
-                        {
-                            let rent = rent_collector
-                                .collect_from_created_account(
-                                    address,
-                                    account,
-                                    preserve_rent_epoch_for_rent_exempt_accounts,
-                                )
-                                .rent_amount;
-                            loaded_transaction.rent += rent;
-                            loaded_transaction.rent_debits.insert(
-                                address,
-                                rent,
-                                account.lamports(),
-                            );
-                        }
-
                         // Add to the accounts to store
                         accounts.push((&*address, &*account));
                         signatures.push(Some(tx.signature()));
@@ -3052,7 +3028,6 @@ mod tests {
             &rent_collector,
             &DurableNonce::default(),
             0,
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
         assert_eq!(collected_accounts.len(), 2);
         assert!(collected_accounts
@@ -3536,7 +3511,6 @@ mod tests {
             &rent_collector,
             &durable_nonce,
             0,
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
         assert_eq!(collected_accounts.len(), 2);
         assert_eq!(
@@ -3651,7 +3625,6 @@ mod tests {
             &rent_collector,
             &durable_nonce,
             0,
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
         assert_eq!(collected_accounts.len(), 1);
         let collected_nonce_account = collected_accounts

runtime/src/bank.rs

@@ -4892,7 +4892,6 @@ impl Bank {
             &self.rent_collector,
             &durable_nonce,
             lamports_per_signature,
-            self.preserve_rent_epoch_for_rent_exempt_accounts(),
             self.include_slot_in_hash(),
         );
         let rent_debits = self.collect_rent(&execution_results, loaded_txs);
@@ -5321,15 +5320,12 @@ impl Bank {
         let mut time_hashing_skipped_rewrites_us = 0;
         let mut time_storing_accounts_us = 0;
         let can_skip_rewrites = self.rc.accounts.accounts_db.skip_rewrites || just_rewrites;
-        let preserve_rent_epoch_for_rent_exempt_accounts =
-            self.preserve_rent_epoch_for_rent_exempt_accounts();
         for (pubkey, account, _loaded_slot) in accounts.iter_mut() {
             let (rent_collected_info, measure) =
                 measure!(self.rent_collector.collect_from_existing_account(
                     pubkey,
                     account,
                     self.rc.accounts.accounts_db.filler_account_suffix.as_ref(),
-                    preserve_rent_epoch_for_rent_exempt_accounts,
                 ));
             time_collecting_rent_us += measure.as_us();
 
@@ -7411,11 +7407,6 @@ impl Bank {
             .is_active(&feature_set::send_to_tpu_vote_port::id())
     }
 
-    fn preserve_rent_epoch_for_rent_exempt_accounts(&self) -> bool {
-        self.feature_set
-            .is_active(&feature_set::preserve_rent_epoch_for_rent_exempt_accounts::id())
-    }
-
     pub fn read_cost_tracker(&self) -> LockResult<RwLockReadGuard<CostTracker>> {
         self.cost_tracker.read()
     }
@@ -8415,7 +8406,6 @@ pub(crate) mod tests {
                 &keypairs[4].pubkey(),
                 &mut account_copy,
                 None,
-                true, // preserve_rent_epoch_for_rent_exempt_accounts
             );
             assert_eq!(expected_rent.rent_amount, too_few_lamports);
             assert_eq!(account_copy.lamports(), 0);
@@ -14508,13 +14498,13 @@ pub(crate) mod tests {
             if bank.slot == 64 {
                 assert_eq!(
                     bank.hash().to_string(),
-                    "4u8bxZRLYdQBkWRBwmpcwcQVMCJoEpzY7hCuAzxr3kCe"
+                    "Ddk6ouAvSSA1U3Cw6BoKdM5v5LdRc9ShruGDzci9fKbY"
                 );
             }
             if bank.slot == 128 {
                 assert_eq!(
                     bank.hash().to_string(),
-                    "4c5F8UbcDD8FM7qXcfv6BPPo6nHNYJQmN5gHiCMTdEzX"
+                    "ANodC5vnedLWqeAyhcoErzR3ptNansb5YX6UTQ9cfP7S"
                 );
                 break;
             }
@@ -19864,7 +19854,6 @@ pub(crate) mod tests {
                 &keypair.pubkey(),
                 &mut account,
                 None,
-                true, // preserve_rent_epoch_for_rent_exempt_accounts
             );
             assert_eq!(info.account_data_len_reclaimed, data_size as u64);
         }

runtime/src/rent_collector.rs

@@ -125,14 +125,8 @@ impl RentCollector {
         address: &Pubkey,
         account: &mut AccountSharedData,
         filler_account_suffix: Option<&Pubkey>,
-        preserve_rent_epoch_for_rent_exempt_accounts: bool,
     ) -> CollectedInfo {
-        match self.calculate_rent_result(
-            address,
-            account,
-            filler_account_suffix,
-            preserve_rent_epoch_for_rent_exempt_accounts,
-        ) {
+        match self.calculate_rent_result(address, account, filler_account_suffix) {
             RentResult::LeaveAloneNoRent => CollectedInfo::default(),
             RentResult::CollectRent {
                 new_rent_epoch,
@@ -164,7 +158,6 @@ impl RentCollector {
         address: &Pubkey,
         account: &impl ReadableAccount,
         filler_account_suffix: Option<&Pubkey>,
-        preserve_rent_epoch_for_rent_exempt_accounts: bool,
     ) -> RentResult {
         if self.can_skip_rent_collection(address, account, filler_account_suffix) {
             return RentResult::LeaveAloneNoRent;
@@ -172,16 +165,7 @@ impl RentCollector {
         match self.get_rent_due(account) {
             // Rent isn't collected for the next epoch.
             // Make sure to check exempt status again later in current epoch.
-            RentDue::Exempt => {
-                if preserve_rent_epoch_for_rent_exempt_accounts {
-                    RentResult::LeaveAloneNoRent
-                } else {
-                    RentResult::CollectRent {
-                        new_rent_epoch: self.epoch,
-                        rent_due: 0,
-                    }
-                }
-            }
+            RentDue::Exempt => RentResult::LeaveAloneNoRent,
             // Maybe collect rent later, leave account alone.
             RentDue::Paying(0) => RentResult::LeaveAloneNoRent,
             // Rent is collected for next epoch.
@@ -193,20 +177,15 @@ impl RentCollector {
     }
 
     #[must_use = "add to Bank::collected_rent"]
-    pub(crate) fn collect_from_created_account(
+    #[cfg(test)]
+    fn collect_from_created_account(
         &self,
         address: &Pubkey,
         account: &mut AccountSharedData,
-        preserve_rent_epoch_for_rent_exempt_accounts: bool,
     ) -> CollectedInfo {
         // initialize rent_epoch as created at this epoch
         account.set_rent_epoch(self.epoch);
-        self.collect_from_existing_account(
-            address,
-            account,
-            None, // filler_account_suffix
-            preserve_rent_epoch_for_rent_exempt_accounts,
-        )
+        self.collect_from_existing_account(address, account, /*filler_account_suffix:*/ None)
     }
 
     /// Performs easy checks to see if rent collection can be skipped
@@ -281,11 +260,8 @@ mod tests {
         let rent_collector = default_rent_collector_clone_with_epoch(new_epoch);
 
         // collect rent on a newly-created account
-        let collected = rent_collector.collect_from_created_account(
-            &solana_sdk::pubkey::new_rand(),
-            &mut created_account,
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
-        );
+        let collected = rent_collector
+            .collect_from_created_account(&solana_sdk::pubkey::new_rand(), &mut created_account);
         assert!(created_account.lamports() < old_lamports);
         assert_eq!(
             created_account.lamports() + collected.rent_amount,
@@ -299,7 +275,6 @@ mod tests {
             &solana_sdk::pubkey::new_rand(),
             &mut existing_account,
             None, // filler_account_suffix
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
         assert!(existing_account.lamports() < old_lamports);
         assert_eq!(
@@ -333,7 +308,6 @@ mod tests {
             &pubkey,
             &mut account,
             None, // filler_account_suffix
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
         assert_eq!(account.lamports(), huge_lamports);
         assert_eq!(collected, CollectedInfo::default());
@@ -346,7 +320,6 @@ mod tests {
             &pubkey,
             &mut account,
             None, // filler_account_suffix
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
         assert_eq!(account.lamports(), tiny_lamports - collected.rent_amount);
         assert_ne!(collected, CollectedInfo::default());
@@ -370,7 +343,6 @@ mod tests {
             &pubkey,
             &mut account,
             None, // filler_account_suffix
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
         assert_eq!(account.lamports(), 0);
         assert_eq!(collected.rent_amount, 1);
@@ -395,7 +367,6 @@ mod tests {
             &Pubkey::new_unique(),
             &mut account,
             None, // filler_account_suffix
-            true, // preserve_rent_epoch_for_rent_exempt_accounts
         );
 
         assert_eq!(collected.rent_amount, account_lamports);