[AHM] Revert multi-block election, slashing and staking client pallets (paritytech#7939)

Revert the following PRs which we are pulling from release stable2503:
- paritytech#7582
- paritytech#7424
- paritytech#7282

and leave pallet-staking in its pre-AHM state.

## Context

We are forking pallet-staking into `pallet-staking` (also referred as
staking-classic, this is the version that will stay on RC) and
`pallet-staking-next` which will live on AH post AHM.

Additional context:
paritytech#7858 (comment)

These changes in crate `pallet-staking` will become the staking classic.
The staking next version is worked in the PR paritytech#7601.

## For AHM migration
The `UnappliedSlashes` storage will need to be translated from
`rc::staking-classic` to `ah::staking-next`.
[Bookmarking](https://github.com/paritytech/polkadot-sdk/blob/master/substrate/frame/staking/src/migrations.rs#L91)
the code that can be referred for this.

## Follow ups
(cc: @tdimitrov and @seadanda )
1) Revert pallet-staking v17 migration in westend.
- Update `in code storage version` of pallet-staking storage from 17 to
16 (separate PR).
- Update `on chain storage version` of pallet-staking storage from 17 to
16. The storage key for pallet-staking on chain version is
`0x5f3e4907f716ac89b6347d15ececedca4e7b9012096b41c4eb3aaf947f6ea429`
which should be set currently to `0x1100`, and needs to be updated to
`0x1000`.
- After the runtime upgrade with the code from this PR is deployed on
Westend, kill the following storage prefixes under the Pallet prefix
`Staking`:
  - OffenceQueue
  - OffenceQueueEras
  - ProcessingOffence
- UnappliedSlashes: This also exists in staking-classic as a storage map
(one key) and in pre-revert code as double storage map (two keys).
Killing with prefix `UnappliedSlashes` may kill the ones created post
upgrade (but that's okay for westend).
  - VoterSnapshotStatus
  - NextElectionPage
  - ElectableStashes

2) Remove exposure dependency
Worked in the PR: paritytech#7936.

---------

Co-authored-by: Tsvetomir Dimitrov <[email protected]>
Co-authored-by: Maciej <[email protected]>

Author: 3 people

.github/workflows/runtimes-matrix.json

@@ -6,7 +6,7 @@
     "header": "substrate/HEADER-APACHE2",
     "template": "substrate/.maintain/frame-weight-template.hbs",
     "bench_features": "runtime-benchmarks",
-    "bench_flags": "--exclude-pallets=pallet_xcm,pallet_xcm_benchmarks::fungible,pallet_xcm_benchmarks::generic,pallet_nomination_pools,pallet_remark,pallet_transaction_storage,pallet_election_provider_multi_block,pallet_election_provider_multi_block::signed,pallet_election_provider_multi_block::unsigned,pallet_election_provider_multi_block::verifier",
+    "bench_flags": "--exclude-pallets=pallet_xcm,pallet_xcm_benchmarks::fungible,pallet_xcm_benchmarks::generic,pallet_nomination_pools,pallet_remark,pallet_transaction_storage",
     "uri": null,
     "is_relay": false
   },

.github/workflows/tests.yml

@@ -35,7 +35,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: script
-        run: forklift cargo run --locked --release -p staging-node-cli --bin substrate-node --features runtime-benchmarks --quiet -- benchmark pallet --chain dev --pallet "*" --exclude-pallets=pallet_election_provider_multi_block,pallet_election_provider_multi_block::signed,pallet_election_provider_multi_block::unsigned,pallet_election_provider_multi_block::verifier --extrinsic "*" --steps 2 --repeat 1 --quiet
+        run: forklift cargo run --locked --release -p staging-node-cli --bin substrate-node --features runtime-benchmarks --quiet -- benchmark pallet --chain dev --pallet "*" --extrinsic "*" --steps 2 --repeat 1 --quiet
 
   # cf https://github.com/paritytech/polkadot-sdk/issues/1652
   test-syscalls:

Cargo.lock

@@ -346,7 +346,6 @@ members = [
 	"substrate/frame/core-fellowship",
 	"substrate/frame/delegated-staking",
 	"substrate/frame/democracy",
-	"substrate/frame/election-provider-multi-block",
 	"substrate/frame/election-provider-multi-phase",
 	"substrate/frame/election-provider-multi-phase/test-staking-e2e",
 	"substrate/frame/election-provider-support",
@@ -422,8 +421,6 @@ members = [
 	"substrate/frame/session/benchmarking",
 	"substrate/frame/society",
 	"substrate/frame/staking",
-	"substrate/frame/staking/ah-client",
-	"substrate/frame/staking/rc-client",
 	"substrate/frame/staking/reward-curve",
 	"substrate/frame/staking/reward-fn",
 	"substrate/frame/staking/runtime-api",
@@ -1005,8 +1002,6 @@ pallet-session-benchmarking = { path = "substrate/frame/session/benchmarking", d
 pallet-skip-feeless-payment = { path = "substrate/frame/transaction-payment/skip-feeless-payment", default-features = false }
 pallet-society = { path = "substrate/frame/society", default-features = false }
 pallet-staking = { path = "substrate/frame/staking", default-features = false }
-pallet-staking-ah-client = { path = "substrate/frame/staking/ah-client", default-features = false }
-pallet-staking-rc-client = { path = "substrate/frame/staking/rc-client", default-features = false }
 pallet-staking-reward-curve = { path = "substrate/frame/staking/reward-curve", default-features = false }
 pallet-staking-reward-fn = { path = "substrate/frame/staking/reward-fn", default-features = false }
 pallet-staking-runtime-api = { path = "substrate/frame/staking/runtime-api", default-features = false }

Cargo.toml

@@ -19,7 +19,7 @@ use sp_authority_discovery::AuthorityId as AuthorityDiscoveryId;
 use sp_consensus_babe::AuthorityId as BabeId;
 use sp_consensus_beefy::ecdsa_crypto::AuthorityId as BeefyId;
 use sp_core::storage::Storage;
-use sp_runtime::{BoundedVec, Perbill};
+use sp_runtime::Perbill;
 
 // Polkadot
 use polkadot_primitives::{AssignmentId, ValidatorId};
@@ -87,13 +87,7 @@ pub fn genesis() -> Storage {
 				.iter()
 				.map(|x| (x.0.clone(), x.1.clone(), STASH, pallet_staking::StakerStatus::Validator))
 				.collect(),
-			invulnerables: BoundedVec::try_from(
-				validators::initial_authorities()
-					.iter()
-					.map(|x| x.0.clone())
-					.collect::<Vec<_>>(),
-			)
-			.expect("Limit for staking invulnerables must be less than initial authorities."),
+			invulnerables: validators::initial_authorities().iter().map(|x| x.0.clone()).collect(),
 			force_era: pallet_staking::Forcing::ForceNone,
 			slash_reward_fraction: Perbill::from_percent(10),
 			..Default::default()

cumulus/parachains/integration-tests/emulated/chains/relays/westend/src/genesis.rs

@@ -82,12 +82,8 @@ where
 
 	pallet_session::Pallet::<T>::on_initialize(BlockNumberFor::<T>::one());
 	initializer::Pallet::<T>::on_initialize(BlockNumberFor::<T>::one());
-
 	// skip sessions until the new validator set is enacted
 	while pallet_session::Pallet::<T>::validators().len() < n as usize {
-		// initialize stakers in pallet_staking. This is suboptimal, but an easy way to avoid this
-		// being an infinite loop.
-		pallet_staking::Pallet::<T>::populate_staking_election_testing_benchmarking_only().unwrap();
 		pallet_session::Pallet::<T>::rotate_session();
 	}
 	initializer::Pallet::<T>::on_finalize(BlockNumberFor::<T>::one());

polkadot/runtime/parachains/src/disputes/slashing/benchmarking.rs

@@ -79,7 +79,7 @@ use polkadot_runtime_common::{
 use polkadot_runtime_parachains::reward_points::RewardValidatorsWithEraPoints;
 use sp_authority_discovery::AuthorityId as AuthorityDiscoveryId;
 use sp_consensus_beefy::ecdsa_crypto::{AuthorityId as BeefyId, Signature as BeefySignature};
-use sp_core::{ConstBool, ConstU32, OpaqueMetadata};
+use sp_core::{ConstU32, OpaqueMetadata};
 use sp_mmr_primitives as mmr;
 use sp_runtime::{
 	curve::PiecewiseLinear,
@@ -349,7 +349,7 @@ parameter_types! {
 	pub const MaxExposurePageSize: u32 = 64;
 	pub const MaxNominators: u32 = 256;
 	pub const MaxAuthorities: u32 = 100_000;
-	pub const OnChainMaxWinners: u32 = MaxAuthorities::get();
+	pub const OnChainMaxWinners: u32 = u32::MAX;
 	// Unbounded number of election targets and voters.
 	pub ElectionBoundsOnChain: ElectionBounds = ElectionBoundsBuilder::default().build();
 }
@@ -362,9 +362,7 @@ impl onchain::Config for OnChainSeqPhragmen {
 	type DataProvider = Staking;
 	type WeightInfo = ();
 	type Bounds = ElectionBoundsOnChain;
-	type MaxWinnersPerPage = OnChainMaxWinners;
-	type MaxBackersPerWinner = ConstU32<{ u32::MAX }>;
-	type Sort = ConstBool<true>;
+	type MaxWinners = OnChainMaxWinners;
 }
 
 /// Upper limit on the number of NPOS nominations.
@@ -402,9 +400,6 @@ impl pallet_staking::Config for Runtime {
 	type BenchmarkingConfig = polkadot_runtime_common::StakingBenchmarkingConfig;
 	type EventListeners = ();
 	type WeightInfo = ();
-	type MaxValidatorSet = MaxAuthorities;
-	type MaxInvulnerables = ConstU32<20>;
-	type MaxDisabledValidators = ConstU32<100>;
 	type Filter = frame_support::traits::Nothing;
 }
 

polkadot/runtime/test-runtime/src/lib.rs

@@ -33,7 +33,7 @@ use sp_consensus_grandpa::AuthorityId as GrandpaId;
 use sp_core::{crypto::get_public_from_string_or_panic, sr25519};
 use sp_genesis_builder::PresetId;
 use sp_keyring::Sr25519Keyring;
-use sp_runtime::{BoundedVec, Perbill};
+use sp_runtime::Perbill;
 use westend_runtime_constants::currency::UNITS as WND;
 
 /// Helper function to generate stash, controller and session key from seed
@@ -202,10 +202,7 @@ fn westend_testnet_genesis(
 				.iter()
 				.map(|x| (x.0.clone(), x.0.clone(), STASH, StakerStatus::<AccountId>::Validator))
 				.collect::<Vec<_>>(),
-			invulnerables: BoundedVec::try_from(
-					initial_authorities.iter().map(|x| x.0.clone()).collect::<Vec<_>>()
-				)
-				.expect("Too many invulnerable validators: upper limit is MaxInvulnerables from pallet staking config"),
+			invulnerables: initial_authorities.iter().map(|x| x.0.clone()).collect::<Vec<_>>(),
 			force_era: Forcing::NotForcing,
 			slash_reward_fraction: Perbill::from_percent(10),
 		},
@@ -376,10 +373,7 @@ fn westend_staging_testnet_config_genesis() -> serde_json::Value {
 				.iter()
 				.map(|x| (x.0.clone(), x.0.clone(), STASH, StakerStatus::<AccountId>::Validator))
 				.collect::<Vec<_>>(),
-			invulnerables: BoundedVec::try_from(
-					initial_authorities.iter().map(|x| x.0.clone()).collect::<Vec<_>>()
-				)
-				.expect("Too many invulnerable validators: upper limit is MaxInvulnerables from pallet staking config"),
+			invulnerables: initial_authorities.iter().map(|x| x.0.clone()).collect::<Vec<_>>(),
 			force_era: Forcing::ForceNone,
 			slash_reward_fraction: Perbill::from_percent(10),
 		},

polkadot/runtime/westend/src/genesis_config_presets.rs

@@ -96,7 +96,7 @@ use sp_consensus_beefy::{
 	ecdsa_crypto::{AuthorityId as BeefyId, Signature as BeefySignature},
 	mmr::{BeefyDataProvider, MmrLeafVersion},
 };
-use sp_core::{ConstBool, ConstU8, OpaqueMetadata, RuntimeDebug, H256};
+use sp_core::{ConstU8, OpaqueMetadata, RuntimeDebug, H256};
 use sp_runtime::{
 	generic, impl_opaque_keys,
 	traits::{
@@ -586,10 +586,7 @@ parameter_types! {
 		ElectionBoundsBuilder::default().voters_count(MaxElectingVoters::get().into()).build();
 	// Maximum winners that can be chosen as active validators
 	pub const MaxActiveValidators: u32 = 1000;
-	// One page only, fill the whole page with the `MaxActiveValidators`.
-	pub const MaxWinnersPerPage: u32 = MaxActiveValidators::get();
-	// Unbonded, thus the max backers per winner maps to the max electing voters limit.
-	pub const MaxBackersPerWinner: u32 = MaxElectingVoters::get();
+
 }
 
 frame_election_provider_support::generate_solution_type!(
@@ -604,14 +601,12 @@ frame_election_provider_support::generate_solution_type!(
 
 pub struct OnChainSeqPhragmen;
 impl onchain::Config for OnChainSeqPhragmen {
-	type Sort = ConstBool<true>;
 	type System = Runtime;
 	type Solver = SequentialPhragmen<AccountId, OnChainAccuracy>;
 	type DataProvider = Staking;
 	type WeightInfo = weights::frame_election_provider_support::WeightInfo<Runtime>;
+	type MaxWinners = MaxActiveValidators;
 	type Bounds = ElectionBounds;
-	type MaxBackersPerWinner = MaxBackersPerWinner;
-	type MaxWinnersPerPage = MaxWinnersPerPage;
 }
 
 impl pallet_election_provider_multi_phase::MinerConfig for Runtime {
@@ -624,8 +619,7 @@ impl pallet_election_provider_multi_phase::MinerConfig for Runtime {
     as
     frame_election_provider_support::ElectionDataProvider
     >::MaxVotesPerVoter;
-	type MaxBackersPerWinner = MaxBackersPerWinner;
-	type MaxWinners = MaxWinnersPerPage;
+	type MaxWinners = MaxActiveValidators;
 
 	// The unsigned submissions have to respect the weight of the submit_unsigned call, thus their
 	// weight estimate function is wired to this call's weight.
@@ -659,8 +653,6 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type BetterSignedThreshold = ();
 	type OffchainRepeat = OffchainRepeat;
 	type MinerTxPriority = NposSolutionPriority;
-	type MaxWinners = MaxWinnersPerPage;
-	type MaxBackersPerWinner = MaxBackersPerWinner;
 	type DataProvider = Staking;
 	#[cfg(any(feature = "fast-runtime", feature = "runtime-benchmarks"))]
 	type Fallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
@@ -669,8 +661,7 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 		AccountId,
 		BlockNumber,
 		Staking,
-		MaxWinnersPerPage,
-		MaxBackersPerWinner,
+		MaxActiveValidators,
 	)>;
 	type GovernanceFallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type Solver = SequentialPhragmen<
@@ -681,6 +672,7 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type BenchmarkingConfig = polkadot_runtime_common::elections::BenchmarkConfig;
 	type ForceOrigin = EnsureRoot<AccountId>;
 	type WeightInfo = weights::pallet_election_provider_multi_phase::WeightInfo<Self>;
+	type MaxWinners = MaxActiveValidators;
 	type ElectionBounds = ElectionBounds;
 }
 
@@ -762,16 +754,13 @@ impl pallet_staking::Config for Runtime {
 	type GenesisElectionProvider = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type VoterList = VoterList;
 	type TargetList = UseValidatorsMap<Self>;
-	type MaxValidatorSet = MaxActiveValidators;
 	type NominationsQuota = pallet_staking::FixedNominationsQuota<{ MaxNominations::get() }>;
 	type MaxUnlockingChunks = frame_support::traits::ConstU32<32>;
 	type HistoryDepth = frame_support::traits::ConstU32<84>;
 	type MaxControllersInDeprecationBatch = MaxControllersInDeprecationBatch;
 	type BenchmarkingConfig = polkadot_runtime_common::StakingBenchmarkingConfig;
 	type EventListeners = (NominationPools, DelegatedStaking);
 	type WeightInfo = weights::pallet_staking::WeightInfo<Runtime>;
-	type MaxInvulnerables = frame_support::traits::ConstU32<20>;
-	type MaxDisabledValidators = ConstU32<100>;
 	type Filter = Nothing;
 }
 
@@ -1909,7 +1898,6 @@ pub mod migrations {
 		parachains_shared::migration::MigrateToV1<Runtime>,
 		parachains_scheduler::migration::MigrateV2ToV3<Runtime>,
 		pallet_staking::migrations::v16::MigrateV15ToV16<Runtime>,
-		pallet_staking::migrations::v17::MigrateV16ToV17<Runtime>,
 		pallet_session::migrations::v1::MigrateV0ToV1<
 			Runtime,
 			pallet_staking::migrations::v17::MigrateDisabledToSession<Runtime>,