Populate EpochRewards with correct data (solana-labs#763)

* Populate EpochRewards::parent_blockhash correctly

* Populate EpochRewards::num_partitions correctly

* Add new internal struct to be extended

* Add CalculateValidatorRewardsResult::total_points

* Add PartitionedRewardsCalculation::total_points

* Add CalculateRewardsAndDistributeVoteRewardsResult::total_points

* Populate EpochRewards::total_points correctly

* Nit: reorder fields to match struct definition

* Use Self::last_blockhash() to get parent_blockhash

runtime/src/bank/partitioned_epoch_rewards/calculation.rs

@@ -1,12 +1,13 @@
 use {
     super::{
         epoch_rewards_hasher::hash_rewards_into_partitions, Bank,
-        CalculateRewardsAndDistributeVoteRewardsResult, EpochRewardCalculateParamInfo,
-        PartitionedRewardsCalculation, StakeRewardCalculationPartitioned, VoteRewardsAccounts,
+        CalculateRewardsAndDistributeVoteRewardsResult, CalculateValidatorRewardsResult,
+        EpochRewardCalculateParamInfo, PartitionedRewardsCalculation,
+        StakeRewardCalculationPartitioned, VoteRewardsAccounts,
     },
     crate::bank::{
         PrevEpochInflationRewards, RewardCalcTracer, RewardCalculationEvent, RewardsMetrics,
-        StakeRewardCalculation, VoteAccount,
+        VoteAccount,
     },
     log::info,
     rayon::{
@@ -38,6 +39,7 @@ impl Bank {
         let CalculateRewardsAndDistributeVoteRewardsResult {
             total_rewards,
             distributed_rewards,
+            total_points,
             stake_rewards_by_partition,
         } = self.calculate_rewards_and_distribute_vote_rewards(
             parent_epoch,
@@ -49,11 +51,19 @@ impl Bank {
         let slot = self.slot();
         let credit_start = self.block_height() + self.get_reward_calculation_num_blocks();
 
+        let num_partitions = stake_rewards_by_partition.len() as u64;
+
         self.set_epoch_reward_status_active(stake_rewards_by_partition);
 
         // create EpochRewards sysvar that holds the balance of undistributed rewards with
         // (total_rewards, distributed_rewards, credit_start), total capital will increase by (total_rewards - distributed_rewards)
-        self.create_epoch_rewards_sysvar(total_rewards, distributed_rewards, credit_start);
+        self.create_epoch_rewards_sysvar(
+            total_rewards,
+            distributed_rewards,
+            credit_start,
+            num_partitions,
+            total_points,
+        );
 
         datapoint_info!(
             "epoch-rewards-status-update",
@@ -82,6 +92,7 @@ impl Bank {
             foundation_rate,
             prev_epoch_duration_in_years,
             capitalization,
+            total_points,
         } = self.calculate_rewards_for_partitioning(
             prev_epoch,
             reward_calc_tracer,
@@ -150,6 +161,7 @@ impl Bank {
         CalculateRewardsAndDistributeVoteRewardsResult {
             total_rewards: validator_rewards_paid + total_stake_rewards_lamports,
             distributed_rewards: validator_rewards_paid,
+            total_points,
             stake_rewards_by_partition,
         }
     }
@@ -198,7 +210,11 @@ impl Bank {
 
         let old_vote_balance_and_staked = self.stakes_cache.stakes().vote_balance_and_staked();
 
-        let (vote_account_rewards, mut stake_rewards) = self
+        let CalculateValidatorRewardsResult {
+            vote_rewards_accounts: vote_account_rewards,
+            stake_reward_calculation: mut stake_rewards,
+            total_points,
+        } = self
             .calculate_validator_rewards(
                 prev_epoch,
                 validator_rewards,
@@ -231,6 +247,7 @@ impl Bank {
             foundation_rate,
             prev_epoch_duration_in_years,
             capitalization,
+            total_points,
         }
     }
 
@@ -242,7 +259,7 @@ impl Bank {
         reward_calc_tracer: Option<impl RewardCalcTracer>,
         thread_pool: &ThreadPool,
         metrics: &mut RewardsMetrics,
-    ) -> Option<(VoteRewardsAccounts, StakeRewardCalculation)> {
+    ) -> Option<CalculateValidatorRewardsResult> {
         let stakes = self.stakes_cache.stakes();
         let reward_calculate_param = self.get_epoch_reward_calculate_param_info(&stakes);
 
@@ -253,14 +270,21 @@ impl Bank {
             metrics,
         )
         .map(|point_value| {
-            self.calculate_stake_vote_rewards(
-                &reward_calculate_param,
-                rewarded_epoch,
-                point_value,
-                thread_pool,
-                reward_calc_tracer,
-                metrics,
-            )
+            let total_points = point_value.points;
+            let (vote_rewards_accounts, stake_reward_calculation) = self
+                .calculate_stake_vote_rewards(
+                    &reward_calculate_param,
+                    rewarded_epoch,
+                    point_value,
+                    thread_pool,
+                    reward_calc_tracer,
+                    metrics,
+                );
+            CalculateValidatorRewardsResult {
+                vote_rewards_accounts,
+                stake_reward_calculation,
+                total_points,
+            }
         })
     }
 
@@ -478,8 +502,11 @@ mod tests {
             &mut rewards_metrics,
         );
 
-        let vote_rewards = &calculated_rewards.as_ref().unwrap().0;
-        let stake_rewards = &calculated_rewards.as_ref().unwrap().1;
+        let vote_rewards = &calculated_rewards.as_ref().unwrap().vote_rewards_accounts;
+        let stake_rewards = &calculated_rewards
+            .as_ref()
+            .unwrap()
+            .stake_reward_calculation;
 
         let total_vote_rewards: u64 = vote_rewards
             .rewards

runtime/src/bank/partitioned_epoch_rewards/distribution.rs

@@ -214,7 +214,9 @@ mod tests {
 
         // Set up epoch_rewards sysvar with rewards with 1e9 lamports to distribute.
         let total_rewards = 1_000_000_000;
-        bank.create_epoch_rewards_sysvar(total_rewards, 0, 42);
+        let num_partitions = 2; // num_partitions is arbitrary and unimportant for this test
+        let total_points = (total_rewards * 42) as u128; // total_points is arbitrary for the purposes of this test
+        bank.create_epoch_rewards_sysvar(total_rewards, 0, 42, num_partitions, total_points);
         let pre_epoch_rewards_account = bank.get_account(&sysvar::epoch_rewards::id()).unwrap();
         let expected_balance =
             bank.get_minimum_balance_for_rent_exemption(pre_epoch_rewards_account.data().len());

runtime/src/bank/partitioned_epoch_rewards/mod.rs

@@ -5,7 +5,7 @@ mod epoch_rewards_hasher;
 mod sysvar;
 
 use {
-    super::Bank,
+    super::{Bank, StakeRewardCalculation},
     crate::{stake_account::StakeAccount, stake_history::StakeHistory},
     solana_accounts_db::{
         partitioned_rewards::PartitionedEpochRewardsConfig, stake_rewards::StakeReward,
@@ -50,6 +50,13 @@ pub(super) struct VoteRewardsAccounts {
     pub(super) accounts_to_store: Vec<Option<AccountSharedData>>,
 }
 
+#[derive(Debug, Default)]
+struct CalculateValidatorRewardsResult {
+    vote_rewards_accounts: VoteRewardsAccounts,
+    stake_reward_calculation: StakeRewardCalculation,
+    total_points: u128,
+}
+
 /// hold reward calc info to avoid recalculation across functions
 pub(super) struct EpochRewardCalculateParamInfo<'a> {
     pub(super) stake_history: StakeHistory,
@@ -69,6 +76,7 @@ pub(super) struct PartitionedRewardsCalculation {
     pub(super) foundation_rate: f64,
     pub(super) prev_epoch_duration_in_years: f64,
     pub(super) capitalization: u64,
+    total_points: u128,
 }
 
 /// result of calculating the stake rewards at beginning of new epoch
@@ -84,6 +92,10 @@ pub(super) struct CalculateRewardsAndDistributeVoteRewardsResult {
     pub(super) total_rewards: u64,
     /// distributed vote rewards
     pub(super) distributed_rewards: u64,
+    /// total rewards points calculated for the current epoch, where points
+    /// equals the sum of (delegated stake * credits observed) for all
+    /// delegations
+    pub(super) total_points: u128,
     /// stake rewards that still need to be distributed, grouped by partition
     pub(super) stake_rewards_by_partition: Vec<StakeRewards>,
 }

runtime/src/bank/partitioned_epoch_rewards/sysvar.rs

@@ -20,22 +20,30 @@ impl Bank {
     }
 
     /// Create EpochRewards sysvar with calculated rewards
+    /// This method must be called before a new Bank advances its
+    /// last_blockhash.
     pub(in crate::bank) fn create_epoch_rewards_sysvar(
         &self,
         total_rewards: u64,
         distributed_rewards: u64,
         distribution_starting_block_height: u64,
+        num_partitions: u64,
+        total_points: u128,
     ) {
         assert!(self.is_partitioned_rewards_code_enabled());
 
         assert!(total_rewards >= distributed_rewards);
 
+        let parent_blockhash = self.last_blockhash();
+
         let epoch_rewards = sysvar::epoch_rewards::EpochRewards {
+            distribution_starting_block_height,
+            num_partitions,
+            parent_blockhash,
+            total_points,
             total_rewards,
             distributed_rewards,
-            distribution_starting_block_height,
             active: true,
-            ..sysvar::epoch_rewards::EpochRewards::default()
         };
 
         self.update_sysvar_account(&sysvar::epoch_rewards::id(), |account| {
@@ -109,9 +117,10 @@ mod tests {
         super::*,
         crate::bank::tests::create_genesis_config,
         solana_sdk::{
-            account::ReadableAccount, epoch_schedule::EpochSchedule, feature_set, hash::Hash,
-            native_token::LAMPORTS_PER_SOL,
+            account::ReadableAccount, epoch_schedule::EpochSchedule, feature_set,
+            native_token::LAMPORTS_PER_SOL, pubkey::Pubkey,
         },
+        std::sync::Arc,
     };
 
     /// Test `EpochRewards` sysvar creation, distribution, and burning.
@@ -126,13 +135,15 @@ mod tests {
         bank.activate_feature(&feature_set::enable_partitioned_epoch_reward::id());
 
         let total_rewards = 1_000_000_000; // a large rewards so that the sysvar account is rent-exempted.
+        let num_partitions = 2; // num_partitions is arbitrary and unimportant for this test
+        let total_points = (total_rewards * 42) as u128; // total_points is arbitrary for the purposes of this test
 
         // create epoch rewards sysvar
         let expected_epoch_rewards = sysvar::epoch_rewards::EpochRewards {
             distribution_starting_block_height: 42,
-            num_partitions: 0,
-            parent_blockhash: Hash::default(),
-            total_points: 0,
+            num_partitions,
+            parent_blockhash: bank.last_blockhash(),
+            total_points,
             total_rewards,
             distributed_rewards: 10,
             active: true,
@@ -144,14 +155,32 @@ mod tests {
             sysvar::epoch_rewards::EpochRewards::default()
         );
 
-        bank.create_epoch_rewards_sysvar(total_rewards, 10, 42);
+        bank.create_epoch_rewards_sysvar(total_rewards, 10, 42, num_partitions, total_points);
         let account = bank.get_account(&sysvar::epoch_rewards::id()).unwrap();
         let expected_balance = bank.get_minimum_balance_for_rent_exemption(account.data().len());
         // Expected balance is the sysvar rent-exempt balance
         assert_eq!(account.lamports(), expected_balance);
         let epoch_rewards: sysvar::epoch_rewards::EpochRewards = from_account(&account).unwrap();
         assert_eq!(epoch_rewards, expected_epoch_rewards);
 
+        // Create a child bank to test parent_blockhash
+        let parent_blockhash = bank.last_blockhash();
+        let parent_slot = bank.slot();
+        let bank = Bank::new_from_parent(Arc::new(bank), &Pubkey::default(), parent_slot + 1);
+        // Also note that running `create_epoch_rewards_sysvar()` against a bank
+        // with an existing EpochRewards sysvar clobbers the previous values
+        bank.create_epoch_rewards_sysvar(total_rewards, 10, 42, num_partitions, total_points);
+
+        let expected_epoch_rewards = sysvar::epoch_rewards::EpochRewards {
+            distribution_starting_block_height: 42,
+            num_partitions,
+            parent_blockhash,
+            total_points,
+            total_rewards,
+            distributed_rewards: 10,
+            active: true,
+        };
+
         let epoch_rewards = bank.get_epoch_rewards_sysvar();
         assert_eq!(epoch_rewards, expected_epoch_rewards);
 
@@ -163,9 +192,9 @@ mod tests {
         let epoch_rewards: sysvar::epoch_rewards::EpochRewards = from_account(&account).unwrap();
         let expected_epoch_rewards = sysvar::epoch_rewards::EpochRewards {
             distribution_starting_block_height: 42,
-            num_partitions: 0,
-            parent_blockhash: Hash::default(),
-            total_points: 0,
+            num_partitions,
+            parent_blockhash,
+            total_points,
             total_rewards,
             distributed_rewards: 20,
             active: true,

runtime/src/bank/sysvar_cache.rs

@@ -6,7 +6,7 @@ mod tests {
     use {
         super::*,
         solana_sdk::{
-            feature_set, genesis_config::create_genesis_config, hash::Hash, pubkey::Pubkey,
+            feature_set, genesis_config::create_genesis_config, pubkey::Pubkey,
             sysvar::epoch_rewards::EpochRewards,
         },
         std::sync::Arc,
@@ -120,11 +120,13 @@ mod tests {
 
         // inject a reward sysvar for test
         bank1.activate_feature(&feature_set::enable_partitioned_epoch_reward::id());
+        let num_partitions = 2; // num_partitions is arbitrary and unimportant for this test
+        let total_points = 42_000; // total_points is arbitrary for the purposes of this test
         let expected_epoch_rewards = EpochRewards {
             distribution_starting_block_height: 42,
-            num_partitions: 0,
-            parent_blockhash: Hash::default(),
-            total_points: 0,
+            num_partitions,
+            parent_blockhash: bank1.parent().unwrap().last_blockhash(),
+            total_points,
             total_rewards: 100,
             distributed_rewards: 10,
             active: true,
@@ -133,6 +135,8 @@ mod tests {
             expected_epoch_rewards.total_rewards,
             expected_epoch_rewards.distributed_rewards,
             expected_epoch_rewards.distribution_starting_block_height,
+            num_partitions,
+            total_points,
         );
 
         bank1