Fix benchmark with new XCM::V3 MAX_INSTRUCTIONS_TO_DECODE (#2514)

* Fix benchmark with new XCM::V3 MAX_INSTRUCTIONS_TO_DECODE

* Small refactor

* `ClearOrigin` replaced by ExpectPallet

* Doc

* Spellcheck

* Fixes and pr reviews

Author: bkontur

bridges/bin/millau/runtime/src/lib.rs

@@ -1036,6 +1036,7 @@ impl_runtime_apis! {
 			];
 
 			use bridge_runtime_common::messages_benchmarking::{
+				generate_xcm_builder_bridge_message_sample,
 				prepare_message_delivery_proof_from_grandpa_chain,
 				prepare_message_delivery_proof_from_parachain,
 				prepare_message_proof_from_grandpa_chain,
@@ -1070,7 +1071,7 @@ impl_runtime_apis! {
 						Runtime,
 						WithRialtoParachainsInstance,
 						WithRialtoParachainMessageBridge,
-					>(params, xcm::v3::Junctions::Here)
+					>(params, generate_xcm_builder_bridge_message_sample(xcm::v3::Junctions::Here))
 				}
 
 				fn prepare_message_delivery_proof(
@@ -1101,7 +1102,7 @@ impl_runtime_apis! {
 						Runtime,
 						RialtoGrandpaInstance,
 						WithRialtoMessageBridge,
-					>(params, xcm::v3::Junctions::Here)
+					>(params, generate_xcm_builder_bridge_message_sample(xcm::v3::Junctions::Here))
 				}
 
 				fn prepare_message_delivery_proof(

bridges/bin/runtime-common/src/messages_benchmarking.rs

@@ -29,7 +29,7 @@ use crate::{
 	},
 };
 
-use bp_messages::storage_keys;
+use bp_messages::{storage_keys, MessagePayload};
 use bp_polkadot_core::parachains::ParaHash;
 use bp_runtime::{
 	record_all_trie_keys, Chain, Parachain, RawStorageProof, StorageProofSize, UnderlyingChainOf,
@@ -45,8 +45,8 @@ use xcm::v3::prelude::*;
 /// Prepare inbound bridge message according to given message proof parameters.
 fn prepare_inbound_message(
 	params: &MessageProofParams,
-	destination: InteriorMultiLocation,
-) -> Vec<u8> {
+	successful_dispatch_message_generator: impl Fn(usize) -> MessagePayload,
+) -> MessagePayload {
 	// we only care about **this** message size when message proof needs to be `Minimal`
 	let expected_size = match params.size {
 		StorageProofSize::Minimal(size) => size as usize,
@@ -58,20 +58,15 @@ fn prepare_inbound_message(
 		return vec![0u8; expected_size]
 	}
 
-	// else let's prepare successful message. For XCM bridge hubs, it is the message that
-	// will be pushed further to some XCM queue (XCMP/UMP)
-	let location = xcm::VersionedInteriorMultiLocation::V3(destination);
-	let location_encoded_size = location.encoded_size();
-
-	// we don't need to be super-precise with `expected_size` here
-	let xcm_size = expected_size.saturating_sub(location_encoded_size);
-	let xcm = xcm::VersionedXcm::<()>::V3(vec![Instruction::ClearOrigin; xcm_size].into());
-
-	// this is the `BridgeMessage` from polkadot xcm builder, but it has no constructor
-	// or public fields, so just tuple
-	// (double encoding, because `.encode()` is called on original Xcm BLOB when it is pushed
-	// to the storage)
-	(location, xcm).encode().encode()
+	// else let's prepare successful message.
+	let msg = successful_dispatch_message_generator(expected_size);
+	assert!(
+		msg.len() >= expected_size,
+		"msg.len(): {} does not match expected_size: {}",
+		expected_size,
+		msg.len()
+	);
+	msg
 }
 
 /// Prepare proof of messages for the `receive_messages_proof` call.
@@ -84,7 +79,7 @@ fn prepare_inbound_message(
 /// function.
 pub fn prepare_message_proof_from_grandpa_chain<R, FI, B>(
 	params: MessageProofParams,
-	message_destination: InteriorMultiLocation,
+	message_generator: impl Fn(usize) -> MessagePayload,
 ) -> (FromBridgedChainMessagesProof<HashOf<BridgedChain<B>>>, Weight)
 where
 	R: pallet_bridge_grandpa::Config<FI, BridgedChain = UnderlyingChainOf<BridgedChain<B>>>,
@@ -97,7 +92,7 @@ where
 		params.message_nonces.clone(),
 		params.outbound_lane_data.clone(),
 		params.size,
-		prepare_inbound_message(&params, message_destination),
+		prepare_inbound_message(&params, message_generator),
 		encode_all_messages,
 		encode_lane_data,
 	);
@@ -127,7 +122,7 @@ where
 /// `prepare_message_proof_from_grandpa_chain` function.
 pub fn prepare_message_proof_from_parachain<R, PI, B>(
 	params: MessageProofParams,
-	message_destination: InteriorMultiLocation,
+	message_generator: impl Fn(usize) -> MessagePayload,
 ) -> (FromBridgedChainMessagesProof<HashOf<BridgedChain<B>>>, Weight)
 where
 	R: pallet_bridge_parachains::Config<PI>,
@@ -141,7 +136,7 @@ where
 		params.message_nonces.clone(),
 		params.outbound_lane_data.clone(),
 		params.size,
-		prepare_inbound_message(&params, message_destination),
+		prepare_inbound_message(&params, message_generator),
 		encode_all_messages,
 		encode_lane_data,
 	);
@@ -291,3 +286,53 @@ where
 	pallet_bridge_parachains::initialize_for_benchmarks::<R, PI, PC>(bridged_header);
 	(bridged_block_number, bridged_header_hash)
 }
+
+/// Returns callback which generates `BridgeMessage` from Polkadot XCM builder based on
+/// `expected_message_size` for benchmark.
+pub fn generate_xcm_builder_bridge_message_sample(
+	destination: InteriorMultiLocation,
+) -> impl Fn(usize) -> MessagePayload {
+	move |expected_message_size| -> MessagePayload {
+		// For XCM bridge hubs, it is the message that
+		// will be pushed further to some XCM queue (XCMP/UMP)
+		let location = xcm::VersionedInteriorMultiLocation::V3(destination);
+		let location_encoded_size = location.encoded_size();
+
+		// we don't need to be super-precise with `expected_size` here
+		let xcm_size = expected_message_size.saturating_sub(location_encoded_size);
+		let xcm_data_size = xcm_size.saturating_sub(
+			// minus empty instruction size
+			xcm::v3::Instruction::<()>::ExpectPallet {
+				index: 0,
+				name: vec![],
+				module_name: vec![],
+				crate_major: 0,
+				min_crate_minor: 0,
+			}
+			.encoded_size(),
+		);
+
+		log::trace!(
+			target: "runtime::bridge-benchmarks",
+			"generate_xcm_builder_bridge_message_sample with expected_message_size: {}, location_encoded_size: {}, xcm_size: {}, xcm_data_size: {}",
+			expected_message_size, location_encoded_size, xcm_size, xcm_data_size,
+		);
+
+		let xcm = xcm::VersionedXcm::<()>::V3(
+			vec![xcm::v3::Instruction::<()>::ExpectPallet {
+				index: 0,
+				name: vec![42; xcm_data_size],
+				module_name: vec![],
+				crate_major: 0,
+				min_crate_minor: 0,
+			}]
+			.into(),
+		);
+
+		// this is the `BridgeMessage` from polkadot xcm builder, but it has no constructor
+		// or public fields, so just tuple
+		// (double encoding, because `.encode()` is called on original Xcm BLOB when it is pushed
+		// to the storage)
+		(location, xcm).encode().encode()
+	}
+}

bridges/modules/messages/src/weights_ext.rs

@@ -29,8 +29,8 @@ pub const EXPECTED_DEFAULT_MESSAGE_LENGTH: u32 = 128;
 /// calls we're checking here would fit 1KB.
 const SIGNED_EXTENSIONS_SIZE: u32 = 1024;
 
-/// Number of extra bytes (excluding size of storage value itself) of storage proof, built at
-/// Rialto chain. This mostly depends on number of entries (and their density) in the storage trie.
+/// Number of extra bytes (excluding size of storage value itself) of storage proof.
+/// This mostly depends on number of entries (and their density) in the storage trie.
 /// Some reserve is reserved to account future chain growth.
 pub const EXTRA_STORAGE_PROOF_SIZE: u32 = 1024;