Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

fix(mempool): avoid concurrent map read and write from priority nonce mempool #21379

Closed
wants to merge 11 commits into from
Closed
1 change: 1 addition & 0 deletions CHANGELOG.md
Original file line number Diff line number Diff line change
Expand Up @@ -264,6 +264,7 @@ Every module contains its own CHANGELOG.md. Please refer to the module you are i
* (baseapp) [#20107](https://github.com/cosmos/cosmos-sdk/pull/20107) Avoid header height overwrite block height.
* (cli) [#20020](https://github.com/cosmos/cosmos-sdk/pull/20020) Make bootstrap-state command support both new and legacy genesis format.
* (testutil/sims) [#20151](https://github.com/cosmos/cosmos-sdk/pull/20151) Set all signatures and don't overwrite the previous one in `GenSignedMockTx`.
* (mempool) [#21379](https://github.com/cosmos/cosmos-sdk/pull/21379) Avoid concurrent map read and map write in priority nonce mempool.

## [v0.50.6](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.50.6) - 2024-04-22

Expand Down
4 changes: 2 additions & 2 deletions scripts/build/localnet.mk
Original file line number Diff line number Diff line change
Expand Up @@ -8,11 +8,11 @@ localnet-build-dlv:
localnet-build-nodes:
$(DOCKER) run --rm -v $(CURDIR)/.testnets:/data cosmossdk/simd \
testnet init-files -n 4 -o /data --starting-ip-address 192.168.10.2 --keyring-backend=test --listen-ip-address 0.0.0.0
docker-compose up -d
docker compose up -d

#? localnet-stop: Stop localnet node
localnet-stop:
docker-compose down
docker compose down

# localnet-start will run a 4-node testnet locally. The nodes are
# based off the docker images in: ./contrib/images/simd-env
Expand Down
188 changes: 188 additions & 0 deletions types/mempool/priority_index.go
Original file line number Diff line number Diff line change
@@ -0,0 +1,188 @@
package mempool

import (
"sync"

"github.com/huandu/skiplist"
)

// ConcurrentListElement represents a node in a concurrent priority index,
// encapsulating a skiplist element and a read-write mutex for safe concurrent access.
type ConcurrentListElement struct {
*skiplist.Element
mutex *sync.RWMutex
Value interface{}
}

// Next safely retrieves the next node in the priority index.
// It acquires a read lock before accessing the next element and releases it afterward.
func (n *ConcurrentListElement) Next() *ConcurrentListElement {
n.mutex.RLock()
defer n.mutex.RUnlock()
ele := n.Element.Next()
if ele == nil {
return nil
}
return &ConcurrentListElement{
Element: ele,
mutex: n.mutex,
Value: ele.Value,
}
}

type scoreKey struct {
nonce uint64
sender string
}

type score[C comparable] struct {
Priority C
Weight C
}

// ConcurrentSkipList represents a concurrent priority index,
// containing a skiplist and a map to track priority counts.
type ConcurrentSkipList[C comparable] struct {
mutex sync.RWMutex
list *skiplist.SkipList
priorityCounts map[C]int
scores map[scoreKey]score[C]
}

// newConcurrentPriorityIndex initializes a new ConcurrentPriorityIndex.
// It accepts a Comparable for the skiplist and a boolean to determine if counts should be tracked.
func newConcurrentPriorityIndex[C comparable](
listComparable skiplist.Comparable,
priority bool,
) *ConcurrentSkipList[C] {
i := &ConcurrentSkipList[C]{
list: skiplist.New(listComparable),
}
if priority {
i.priorityCounts = make(map[C]int)
i.scores = make(map[scoreKey]score[C])
}
return i
}

// Len returns the number of elements in the priority index.
// It locks the list for reading to ensure safe access.
func (i *ConcurrentSkipList[C]) Len() int {
i.mutex.RLock()
defer i.mutex.RUnlock()
return i.list.Len()
}

// Front retrieves the first node in the priority index.
// It locks the list for reading to ensure safe access.
func (i *ConcurrentSkipList[C]) Front() *ConcurrentListElement {
i.mutex.RLock()
defer i.mutex.RUnlock()
ele := i.list.Front()
if ele == nil {
return nil
}
return &ConcurrentListElement{
Element: ele,
mutex: &i.mutex,
Value: ele.Value,
}
}

// GetCount retrieves the count of a specific key from the priority counts map.
// It locks priorityCounts for reading to ensure safe access.
func (i *ConcurrentSkipList[C]) GetCount(key C) int {
i.mutex.RLock()
defer i.mutex.RUnlock()
if i.priorityCounts == nil {
return -1
}
return i.priorityCounts[key]
}

// CloneCounts creates a copy of the priority counts map.
// It locks priorityCounts for reading to ensure safe access.
func (i *ConcurrentSkipList[C]) CloneCounts() map[C]int {
i.mutex.RLock()
defer i.mutex.RUnlock()
if i.priorityCounts == nil {
return nil
}

counts := make(map[C]int)
for k, v := range i.priorityCounts {
counts[k] = v
}
Comment on lines +113 to +115

Check warning

Code scanning / CodeQL

Iteration over map Warning

Iteration over map may be a possible source of non-determinism
return counts
}

// GetScore retrieves the score associated with a specific nonce and sender.
// It returns a pointer to the score if found, or nil if not found.
// It locks the scores for reading to ensure safe access.
func (i *ConcurrentSkipList[C]) GetScore(nonce uint64, sender string) *score[C] { //revive:disable:unexported-return
i.mutex.RLock()
defer i.mutex.RUnlock()
score, ok := i.scores[scoreKey{nonce: nonce, sender: sender}]
if !ok {
return nil
}
return &score
}

// Get retrieves a node corresponding to a specific key from the priority index.
// It locks the list for reading to ensure safe access.
func (i *ConcurrentSkipList[C]) Get(key txMeta[C]) *ConcurrentListElement {
i.mutex.RLock()
defer i.mutex.RUnlock()
ele := i.list.Get(key)
if ele == nil {
return nil
}
return &ConcurrentListElement{
Element: ele,
mutex: &i.mutex,
Value: ele.Value,
}
}

// Set inserts or updates a node in the priority index with the given key and value.
// It locks priorityCounts, scores and list for writing to ensure safe access and updates the priority count.
func (i *ConcurrentSkipList[C]) Set(key txMeta[C], value any) *ConcurrentListElement {
i.mutex.Lock()
defer i.mutex.Unlock()
if i.priorityCounts != nil {
i.priorityCounts[key.priority]++
}
if i.scores != nil {
i.scores[scoreKey{
nonce: key.nonce,
sender: key.sender,
}] = score[C]{
Priority: key.priority,
Weight: key.weight,
}
}
ele := i.list.Set(key, value)
if ele == nil {
return nil
}
return &ConcurrentListElement{
Element: ele,
mutex: &i.mutex,
Value: ele.Value,
}
}

// Remove deletes a node from the priority index using the specified key.
// It locks priorityCounts and scores for writing to ensure safe access and decrements the priority count.
func (i *ConcurrentSkipList[C]) Remove(key txMeta[C]) {
i.mutex.Lock()
defer i.mutex.Unlock()
if i.priorityCounts != nil {
i.priorityCounts[key.priority]--
}
if i.scores != nil {
delete(i.scores, scoreKey{nonce: key.nonce, sender: key.sender})
}
i.list.Remove(key)
}
Loading
Loading