test(concurrency): multithreaded flow test for the scheduler

crates/blockifier/src/abi/sierra_types.rs

@@ -36,18 +36,23 @@ pub trait SierraType: Sized {
     fn from_memory(vm: &VirtualMachine, ptr: &mut Relocatable) -> SierraTypeResult<Self>;
 
     fn from_storage(
-        state: &mut dyn StateReader,
+        state: &dyn StateReader,
         contract_address: &ContractAddress,
         key: &StorageKey,
     ) -> SierraTypeResult<Self>;
 }
 
 // Utils.
+
 pub fn felt_to_u128(felt: &Felt252) -> Result<u128, SierraTypeError> {
     felt.to_u128()
         .ok_or_else(|| SierraTypeError::ValueTooLargeForType { val: felt.clone(), ty: "u128" })
 }
 
+pub fn stark_felt_to_u128(stark_felt: &StarkFelt) -> Result<u128, SierraTypeError> {
+    felt_to_u128(&stark_felt_to_felt(*stark_felt))
+}
+
 // TODO(barak, 01/10/2023): Move to starknet_api under StorageKey implementation.
 pub fn next_storage_key(key: &StorageKey) -> Result<StorageKey, StarknetApiError> {
     Ok(StorageKey(PatriciaKey::try_from(StarkFelt::from(
@@ -78,7 +83,7 @@ impl SierraType for SierraU128 {
     }
 
     fn from_storage(
-        state: &mut dyn StateReader,
+        state: &dyn StateReader,
         contract_address: &ContractAddress,
         key: &StorageKey,
     ) -> SierraTypeResult<Self> {
@@ -111,7 +116,7 @@ impl SierraType for SierraU256 {
     }
 
     fn from_storage(
-        state: &mut dyn StateReader,
+        state: &dyn StateReader,
         contract_address: &ContractAddress,
         key: &StorageKey,
     ) -> SierraTypeResult<Self> {

crates/blockifier/src/concurrency/flow_test.rs

@@ -0,0 +1,173 @@
+use std::collections::HashMap;
+use std::sync::atomic::Ordering;
+use std::sync::Arc;
+
+use rstest::rstest;
+use starknet_api::core::{ContractAddress, PatriciaKey};
+use starknet_api::hash::{StarkFelt, StarkHash};
+use starknet_api::{contract_address, patricia_key, stark_felt};
+
+use crate::abi::sierra_types::{SierraType, SierraU128};
+use crate::concurrency::scheduler::{Scheduler, Task, TransactionStatus};
+use crate::concurrency::test_utils::{safe_versioned_state_for_testing, DEFAULT_CHUNK_SIZE};
+use crate::concurrency::versioned_state::ThreadSafeVersionedState;
+use crate::state::cached_state::{CachedState, ContractClassMapping, StateMaps};
+use crate::state::state_api::UpdatableState;
+use crate::storage_key;
+use crate::test_utils::dict_state_reader::DictStateReader;
+
+const CONTRACT_ADDRESS: &str = "0x18031991";
+const STORAGE_KEY: u8 = 27;
+
+#[rstest]
+fn scheduler_flow_test(
+    // TODO(barak, 01/07/2024): Add a separate identical test and use the package loom.
+    #[values(1, 2, 4, 32, 64, 128)] num_threads: u8,
+) {
+    // Tests the Scheduler under a heavy load of validation aborts. To do that, we simulate multiple
+    // transactions with multiple threads, where every transaction depends on its predecessor. Each
+    // transaction sequentially advances a counter by reading the previous value and bumping it by
+    // 1.
+    let scheduler = Arc::new(Scheduler::new(DEFAULT_CHUNK_SIZE));
+    let versioned_state =
+        safe_versioned_state_for_testing(CachedState::from(DictStateReader::default()));
+    let mut handles = vec![];
+
+    for _ in 0..num_threads {
+        let scheduler = Arc::clone(&scheduler);
+        let versioned_state = versioned_state.clone();
+        let handle = std::thread::spawn(move || {
+            let mut task = Task::NoTask;
+            loop {
+                if let Some(mut transaction_committer) = scheduler.try_enter_commit_phase() {
+                    while let Some(tx_index) = transaction_committer.try_commit() {
+                        let mut state_proxy = versioned_state.pin_version(tx_index);
+                        let (reads, writes) =
+                            get_reads_writes_for(Task::ValidationTask(tx_index), &versioned_state);
+                        let reads_valid = state_proxy.validate_reads(&reads);
+                        if !reads_valid {
+                            state_proxy.delete_writes(&writes, &ContractClassMapping::default());
+                            let (_, new_writes) = get_reads_writes_for(
+                                Task::ExecutionTask(tx_index),
+                                &versioned_state,
+                            );
+                            state_proxy.apply_writes(
+                                &new_writes,
+                                &ContractClassMapping::default(),
+                                &HashMap::default(),
+                            );
+                            scheduler.finish_execution_during_commit(tx_index);
+                        }
+                    }
+                }
+                task = match task {
+                    Task::ExecutionTask(tx_index) => {
+                        let (_, writes) =
+                            get_reads_writes_for(Task::ExecutionTask(tx_index), &versioned_state);
+                        versioned_state.pin_version(tx_index).apply_writes(
+                            &writes,
+                            &ContractClassMapping::default(),
+                            &HashMap::default(),
+                        );
+                        scheduler.finish_execution(tx_index);
+                        Task::NoTask
+                    }
+                    Task::ValidationTask(tx_index) => {
+                        let state_proxy = versioned_state.pin_version(tx_index);
+                        let (reads, writes) =
+                            get_reads_writes_for(Task::ValidationTask(tx_index), &versioned_state);
+                        let read_set_valid = state_proxy.validate_reads(&reads);
+                        let aborted = !read_set_valid && scheduler.try_validation_abort(tx_index);
+                        if aborted {
+                            state_proxy.delete_writes(&writes, &ContractClassMapping::default());
+                            scheduler.finish_abort(tx_index)
+                        } else {
+                            Task::NoTask
+                        }
+                    }
+                    Task::NoTask => scheduler.next_task(),
+                    Task::Done => break,
+                }
+            }
+        });
+        handles.push(handle);
+    }
+    for handle in handles {
+        handle.join().unwrap();
+    }
+
+    // The execution index can be strictly greater than chunk_size. This is a side effect of using
+    // atomic variables instead of locks, which can encapsulate both the check (whether to increment
+    // the variable or not) and the incrementation in a scope where no other threads can access the
+    // variable.
+    assert!(scheduler.execution_index.load(Ordering::Acquire) >= DEFAULT_CHUNK_SIZE);
+    // There is no guarantee about the validation index because of the use of the commit index.
+    assert!(*scheduler.commit_index.lock().unwrap() == DEFAULT_CHUNK_SIZE);
+    assert!(scheduler.get_n_committed_txs() == DEFAULT_CHUNK_SIZE);
+    assert!(scheduler.done_marker.load(Ordering::Acquire));
+    for tx_index in 0..DEFAULT_CHUNK_SIZE {
+        assert_eq!(*scheduler.tx_statuses[tx_index].lock().unwrap(), TransactionStatus::Committed);
+        let storage_writes = versioned_state.state().get_writes_of_index(tx_index).storage;
+        assert_eq!(
+            *storage_writes
+                .get(&(contract_address!(CONTRACT_ADDRESS), storage_key!(STORAGE_KEY)))
+                .unwrap(),
+            stark_felt!(format!("{:x}", tx_index + 1).as_str())
+        );
+    }
+}
+
+fn get_reads_writes_for(
+    task: Task,
+    versioned_state: &ThreadSafeVersionedState<CachedState<DictStateReader>>,
+) -> (StateMaps, StateMaps) {
+    match task {
+        Task::ExecutionTask(tx_index) => {
+            let state_proxy = match tx_index {
+                0 => {
+                    return (
+                        state_maps_with_single_storage_entry(0),
+                        state_maps_with_single_storage_entry(1),
+                    );
+                }
+                _ => versioned_state.pin_version(tx_index - 1),
+            };
+            let tx_written_value = SierraU128::from_storage(
+                &state_proxy,
+                &contract_address!(CONTRACT_ADDRESS),
+                &storage_key!(STORAGE_KEY),
+            )
+            .unwrap()
+            .as_value();
+            (
+                state_maps_with_single_storage_entry(tx_written_value),
+                state_maps_with_single_storage_entry(tx_written_value + 1),
+            )
+        }
+        Task::ValidationTask(tx_index) => {
+            let state_proxy = versioned_state.pin_version(tx_index);
+            let tx_written_value = SierraU128::from_storage(
+                &state_proxy,
+                &contract_address!(CONTRACT_ADDRESS),
+                &storage_key!(STORAGE_KEY),
+            )
+            .unwrap()
+            .as_value();
+            (
+                state_maps_with_single_storage_entry(tx_written_value - 1),
+                state_maps_with_single_storage_entry(tx_written_value),
+            )
+        }
+        _ => panic!("Only execution and validation tasks shold be used here."),
+    }
+}
+
+fn state_maps_with_single_storage_entry(value: u128) -> StateMaps {
+    StateMaps {
+        storage: HashMap::from([(
+            (contract_address!(CONTRACT_ADDRESS), storage_key!(STORAGE_KEY)),
+            stark_felt!(value),
+        )]),
+        ..Default::default()
+    }
+}

crates/blockifier/src/concurrency/scheduler.rs

@@ -1,4 +1,3 @@
-use std::cmp::min;
 use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
 use std::sync::{Mutex, MutexGuard, TryLockError};
 
@@ -9,6 +8,10 @@ use crate::concurrency::TxIndex;
 #[path = "scheduler_test.rs"]
 pub mod test;
 
+#[cfg(test)]
+#[path = "flow_test.rs"]
+pub mod flow_test;
+
 pub struct TransactionCommitter<'a> {
     scheduler: &'a Scheduler,
     commit_index_guard: MutexGuard<'a, usize>,
@@ -88,10 +91,6 @@ impl Scheduler {
         let index_to_validate = self.validation_index.load(Ordering::Acquire);
         let index_to_execute = self.execution_index.load(Ordering::Acquire);
 
-        if min(index_to_validate, index_to_execute) >= self.chunk_size {
-            return Task::NoTask;
-        }
-
         if index_to_validate < index_to_execute {
             if let Some(tx_index) = self.next_version_to_validate() {
                 return Task::ValidationTask(tx_index);

crates/blockifier/src/concurrency/scheduler_test.rs

@@ -6,11 +6,10 @@ use pretty_assertions::assert_eq;
 use rstest::rstest;
 
 use crate::concurrency::scheduler::{Scheduler, Task, TransactionStatus};
+use crate::concurrency::test_utils::DEFAULT_CHUNK_SIZE;
 use crate::concurrency::TxIndex;
 use crate::default_scheduler;
 
-const DEFAULT_CHUNK_SIZE: usize = 100;
-
 #[rstest]
 fn test_new(#[values(0, 1, 32)] chunk_size: usize) {
     let scheduler = Scheduler::new(chunk_size);

crates/blockifier/src/concurrency/test_utils.rs

@@ -12,6 +12,10 @@ use crate::test_utils::dict_state_reader::DictStateReader;
 use crate::transaction::account_transaction::AccountTransaction;
 use crate::transaction::transactions::ExecutableTransaction;
 
+// Public Consts.
+
+pub const DEFAULT_CHUNK_SIZE: usize = 64;
+
 // Fixtures.
 
 #[fixture]
@@ -54,13 +58,17 @@ macro_rules! default_scheduler {
     };
 }
 
+// Concurrency constructors.
+
 // TODO(meshi, 01/06/2024): Consider making this a macro.
 pub fn safe_versioned_state_for_testing(
     block_state: CachedState<DictStateReader>,
 ) -> ThreadSafeVersionedState<CachedState<DictStateReader>> {
     ThreadSafeVersionedState::new(VersionedState::new(block_state))
 }
 
+// Utils.
+
 // Note: this function does not mutate the state.
 pub fn create_fee_transfer_call_info<S: StateReader>(
     state: &mut CachedState<S>,

crates/blockifier/src/concurrency/versioned_state.rs

@@ -241,6 +241,11 @@ impl<S: StateReader> ThreadSafeVersionedState<S> {
             .into_inner()
             .expect("No other mutex should hold the versioned state while calling this method.")
     }
+
+    #[cfg(test)]
+    pub fn state(&self) -> LockedVersionedState<'_, S> {
+        self.0.lock().expect("Failed to acquire state lock.")
+    }
 }
 
 impl<S: StateReader> Clone for ThreadSafeVersionedState<S> {