eth/downloader: use atomic types (#27030)

* eth/downloader: use atomic type

* Update eth/downloader/downloader_test.go
Co-authored-by: Martin Holst Swende <martin@swende.se>

* Update eth/downloader/downloader_test.go
Co-authored-by: Martin Holst Swende <martin@swende.se>

---------
Co-authored-by: Martin Holst Swende <martin@swende.se>

eth/downloader/beaconsync.go

@@ -19,7 +19,6 @@ package downloader
 import (
 	"fmt"
 	"sync"
-	"sync/atomic"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -371,7 +370,7 @@ func (d *Downloader) fetchBeaconHeaders(from uint64) error {
 			continue
 		}
 		// If the pivot block is committed, signal header sync termination
-		if atomic.LoadInt32(&d.committed) == 1 {
+		if d.committed.Load() {
 			select {
 			case d.headerProcCh <- nil:
 				return nil

eth/downloader/downloader.go

@@ -98,7 +98,7 @@ type headerTask struct {
 }
 
 type Downloader struct {
-	mode uint32         // Synchronisation mode defining the strategy used (per sync cycle), use d.getMode() to get the SyncMode
+	mode atomic.Uint32  // Synchronisation mode defining the strategy used (per sync cycle), use d.getMode() to get the SyncMode
 	mux  *event.TypeMux // Event multiplexer to announce sync operation events
 
 	checkpoint uint64   // Checkpoint block number to enforce head against (e.g. snap sync)
@@ -122,9 +122,9 @@ type Downloader struct {
 
 	// Status
 	synchroniseMock func(id string, hash common.Hash) error // Replacement for synchronise during testing
-	synchronising   int32
-	notified        int32
-	committed       int32
+	synchronising   atomic.Bool
+	notified        atomic.Bool
+	committed       atomic.Bool
 	ancientLimit    uint64 // The maximum block number which can be regarded as ancient data.
 
 	// Channels
@@ -292,7 +292,7 @@ func (d *Downloader) Progress() ethereum.SyncProgress {
 
 // Synchronising returns whether the downloader is currently retrieving blocks.
 func (d *Downloader) Synchronising() bool {
-	return atomic.LoadInt32(&d.synchronising) > 0
+	return d.synchronising.Load()
 }
 
 // RegisterPeer injects a new download peer into the set of block source to be
@@ -392,13 +392,13 @@ func (d *Downloader) synchronise(id string, hash common.Hash, td, ttd *big.Int,
 		return d.synchroniseMock(id, hash)
 	}
 	// Make sure only one goroutine is ever allowed past this point at once
-	if !atomic.CompareAndSwapInt32(&d.synchronising, 0, 1) {
+	if !d.synchronising.CompareAndSwap(false, true) {
 		return errBusy
 	}
-	defer atomic.StoreInt32(&d.synchronising, 0)
+	defer d.synchronising.Store(false)
 
 	// Post a user notification of the sync (only once per session)
-	if atomic.CompareAndSwapInt32(&d.notified, 0, 1) {
+	if d.notified.CompareAndSwap(false, true) {
 		log.Info("Block synchronisation started")
 	}
 	if mode == SnapSync {
@@ -435,7 +435,7 @@ func (d *Downloader) synchronise(id string, hash common.Hash, td, ttd *big.Int,
 	defer d.Cancel() // No matter what, we can't leave the cancel channel open
 
 	// Atomically set the requested sync mode
-	atomic.StoreUint32(&d.mode, uint32(mode))
+	d.mode.Store(uint32(mode))
 
 	// Retrieve the origin peer and initiate the downloading process
 	var p *peerConnection
@@ -452,7 +452,7 @@ func (d *Downloader) synchronise(id string, hash common.Hash, td, ttd *big.Int,
 }
 
 func (d *Downloader) getMode() SyncMode {
-	return SyncMode(atomic.LoadUint32(&d.mode))
+	return SyncMode(d.mode.Load())
 }
 
 // syncWithPeer starts a block synchronization based on the hash chain from the
@@ -562,9 +562,9 @@ func (d *Downloader) syncWithPeer(p *peerConnection, hash common.Hash, td, ttd *
 			rawdb.WriteLastPivotNumber(d.stateDB, pivotNumber)
 		}
 	}
-	d.committed = 1
+	d.committed.Store(true)
 	if mode == SnapSync && pivot.Number.Uint64() != 0 {
-		d.committed = 0
+		d.committed.Store(false)
 	}
 	if mode == SnapSync {
 		// Set the ancient data limitation. If we are running snap sync, all block
@@ -1128,7 +1128,7 @@ func (d *Downloader) fetchHeaders(p *peerConnection, from uint64, head uint64) e
 		// If no more headers are inbound, notify the content fetchers and return
 		if len(headers) == 0 {
 			// Don't abort header fetches while the pivot is downloading
-			if atomic.LoadInt32(&d.committed) == 0 && pivot <= from {
+			if !d.committed.Load() && pivot <= from {
 				p.log.Debug("No headers, waiting for pivot commit")
 				select {
 				case <-time.After(fsHeaderContCheck):
@@ -1669,7 +1669,7 @@ func (d *Downloader) processSnapSyncContent() error {
 			results = append(append([]*fetchResult{oldPivot}, oldTail...), results...)
 		}
 		// Split around the pivot block and process the two sides via snap/full sync
-		if atomic.LoadInt32(&d.committed) == 0 {
+		if !d.committed.Load() {
 			latest := results[len(results)-1].Header
 			// If the height is above the pivot block by 2 sets, it means the pivot
 			// become stale in the network and it was garbage collected, move to a
@@ -1794,7 +1794,7 @@ func (d *Downloader) commitPivotBlock(result *fetchResult) error {
 	if err := d.blockchain.SnapSyncCommitHead(block.Hash()); err != nil {
 		return err
 	}
-	atomic.StoreInt32(&d.committed, 1)
+	d.committed.Store(true)
 	return nil
 }
 

eth/downloader/downloader_test.go

@@ -476,9 +476,10 @@ func testThrottling(t *testing.T, protocol uint, mode SyncMode) {
 	tester.newPeer("peer", protocol, testChainBase.blocks[1:])
 
 	// Wrap the importer to allow stepping
-	blocked, proceed := uint32(0), make(chan struct{})
+	var blocked atomic.Uint32
+	proceed := make(chan struct{})
 	tester.downloader.chainInsertHook = func(results []*fetchResult) {
-		atomic.StoreUint32(&blocked, uint32(len(results)))
+		blocked.Store(uint32(len(results)))
 		<-proceed
 	}
 	// Start a synchronisation concurrently
@@ -505,7 +506,7 @@ func testThrottling(t *testing.T, protocol uint, mode SyncMode) {
 			tester.downloader.queue.resultCache.lock.Lock()
 			{
 				cached = tester.downloader.queue.resultCache.countCompleted()
-				frozen = int(atomic.LoadUint32(&blocked))
+				frozen = int(blocked.Load())
 				retrieved = int(tester.chain.CurrentSnapBlock().Number.Uint64()) + 1
 			}
 			tester.downloader.queue.resultCache.lock.Unlock()
@@ -528,8 +529,8 @@ func testThrottling(t *testing.T, protocol uint, mode SyncMode) {
 			t.Fatalf("block count mismatch: have %v, want %v (owned %v, blocked %v, target %v)", cached, blockCacheMaxItems, retrieved, frozen, targetBlocks+1)
 		}
 		// Permit the blocked blocks to import
-		if atomic.LoadUint32(&blocked) > 0 {
-			atomic.StoreUint32(&blocked, uint32(0))
+		if blocked.Load() > 0 {
+			blocked.Store(uint32(0))
 			proceed <- struct{}{}
 		}
 	}
@@ -786,12 +787,12 @@ func testEmptyShortCircuit(t *testing.T, protocol uint, mode SyncMode) {
 	tester.newPeer("peer", protocol, chain.blocks[1:])
 
 	// Instrument the downloader to signal body requests
-	bodiesHave, receiptsHave := int32(0), int32(0)
+	var bodiesHave, receiptsHave atomic.Int32
 	tester.downloader.bodyFetchHook = func(headers []*types.Header) {
-		atomic.AddInt32(&bodiesHave, int32(len(headers)))
+		bodiesHave.Add(int32(len(headers)))
 	}
 	tester.downloader.receiptFetchHook = func(headers []*types.Header) {
-		atomic.AddInt32(&receiptsHave, int32(len(headers)))
+		receiptsHave.Add(int32(len(headers)))
 	}
 	// Synchronise with the peer and make sure all blocks were retrieved
 	if err := tester.sync("peer", nil, mode); err != nil {
@@ -811,11 +812,11 @@ func testEmptyShortCircuit(t *testing.T, protocol uint, mode SyncMode) {
 			receiptsNeeded++
 		}
 	}
-	if int(bodiesHave) != bodiesNeeded {
-		t.Errorf("body retrieval count mismatch: have %v, want %v", bodiesHave, bodiesNeeded)
+	if int(bodiesHave.Load()) != bodiesNeeded {
+		t.Errorf("body retrieval count mismatch: have %v, want %v", bodiesHave.Load(), bodiesNeeded)
 	}
-	if int(receiptsHave) != receiptsNeeded {
-		t.Errorf("receipt retrieval count mismatch: have %v, want %v", receiptsHave, receiptsNeeded)
+	if int(receiptsHave.Load()) != receiptsNeeded {
+		t.Errorf("receipt retrieval count mismatch: have %v, want %v", receiptsHave.Load(), receiptsNeeded)
 	}
 }
 

eth/downloader/queue.go

@@ -61,7 +61,7 @@ type fetchRequest struct {
 // fetchResult is a struct collecting partial results from data fetchers until
 // all outstanding pieces complete and the result as a whole can be processed.
 type fetchResult struct {
-	pending int32 // Flag telling what deliveries are outstanding
+	pending atomic.Int32 // Flag telling what deliveries are outstanding
 
 	Header       *types.Header
 	Uncles       []*types.Header
@@ -75,38 +75,38 @@ func newFetchResult(header *types.Header, fastSync bool) *fetchResult {
 		Header: header,
 	}
 	if !header.EmptyBody() {
-		item.pending |= (1 << bodyType)
+		item.pending.Store(item.pending.Load() | (1 << bodyType))
 	} else if header.WithdrawalsHash != nil {
 		item.Withdrawals = make(types.Withdrawals, 0)
 	}
 	if fastSync && !header.EmptyReceipts() {
-		item.pending |= (1 << receiptType)
+		item.pending.Store(item.pending.Load() | (1 << receiptType))
 	}
 	return item
 }
 
 // SetBodyDone flags the body as finished.
 func (f *fetchResult) SetBodyDone() {
-	if v := atomic.LoadInt32(&f.pending); (v & (1 << bodyType)) != 0 {
-		atomic.AddInt32(&f.pending, -1)
+	if v := f.pending.Load(); (v & (1 << bodyType)) != 0 {
+		f.pending.Add(-1)
 	}
 }
 
 // AllDone checks if item is done.
 func (f *fetchResult) AllDone() bool {
-	return atomic.LoadInt32(&f.pending) == 0
+	return f.pending.Load() == 0
 }
 
 // SetReceiptsDone flags the receipts as finished.
 func (f *fetchResult) SetReceiptsDone() {
-	if v := atomic.LoadInt32(&f.pending); (v & (1 << receiptType)) != 0 {
-		atomic.AddInt32(&f.pending, -2)
+	if v := f.pending.Load(); (v & (1 << receiptType)) != 0 {
+		f.pending.Add(-2)
 	}
 }
 
 // Done checks if the given type is done already
 func (f *fetchResult) Done(kind uint) bool {
-	v := atomic.LoadInt32(&f.pending)
+	v := f.pending.Load()
 	return v&(1<<kind) == 0
 }
 

eth/downloader/resultstore.go

@@ -33,7 +33,7 @@ type resultStore struct {
 	// Internal index of first non-completed entry, updated atomically when needed.
 	// If all items are complete, this will equal length(items), so
 	// *important* : is not safe to use for indexing without checking against length
-	indexIncomplete int32 // atomic access
+	indexIncomplete atomic.Int32
 
 	// throttleThreshold is the limit up to which we _want_ to fill the
 	// results. If blocks are large, we want to limit the results to less
@@ -146,7 +146,7 @@ func (r *resultStore) HasCompletedItems() bool {
 func (r *resultStore) countCompleted() int {
 	// We iterate from the already known complete point, and see
 	// if any more has completed since last count
-	index := atomic.LoadInt32(&r.indexIncomplete)
+	index := r.indexIncomplete.Load()
 	for ; ; index++ {
 		if index >= int32(len(r.items)) {
 			break
@@ -156,7 +156,7 @@ func (r *resultStore) countCompleted() int {
 			break
 		}
 	}
-	atomic.StoreInt32(&r.indexIncomplete, index)
+	r.indexIncomplete.Store(index)
 	return int(index)
 }
 
@@ -179,7 +179,7 @@ func (r *resultStore) GetCompleted(limit int) []*fetchResult {
 	}
 	// Advance the expected block number of the first cache entry
 	r.resultOffset += uint64(limit)
-	atomic.AddInt32(&r.indexIncomplete, int32(-limit))
+	r.indexIncomplete.Add(int32(-limit))
 
 	return results
 }

eth/downloader/skeleton_test.go

@@ -82,8 +82,8 @@ type skeletonTestPeer struct {
 
 	serve func(origin uint64) []*types.Header // Hook to allow custom responses
 
-	served  uint64 // Number of headers served by this peer
-	dropped uint64 // Flag whether the peer was dropped (stop responding)
+	served  atomic.Uint64 // Number of headers served by this peer
+	dropped atomic.Uint64 // Flag whether the peer was dropped (stop responding)
 }
 
 // newSkeletonTestPeer creates a new mock peer to test the skeleton sync with.
@@ -113,7 +113,7 @@ func (p *skeletonTestPeer) RequestHeadersByNumber(origin uint64, amount int, ski
 	// Since skeleton test peer are in-memory mocks, dropping the does not make
 	// them inaccessible. As such, check a local `dropped` field to see if the
 	// peer has been dropped and should not respond any more.
-	if atomic.LoadUint64(&p.dropped) != 0 {
+	if p.dropped.Load() != 0 {
 		return nil, errors.New("peer already dropped")
 	}
 	// Skeleton sync retrieves batches of headers going backward without gaps.
@@ -161,7 +161,7 @@ func (p *skeletonTestPeer) RequestHeadersByNumber(origin uint64, amount int, ski
 			}
 		}
 	}
-	atomic.AddUint64(&p.served, uint64(len(headers)))
+	p.served.Add(uint64(len(headers)))
 
 	hashes := make([]common.Hash, len(headers))
 	for i, header := range headers {
@@ -182,7 +182,7 @@ func (p *skeletonTestPeer) RequestHeadersByNumber(origin uint64, amount int, ski
 		sink <- res
 		if err := <-res.Done; err != nil {
 			log.Warn("Skeleton test peer response rejected", "err", err)
-			atomic.AddUint64(&p.dropped, 1)
+			p.dropped.Add(1)
 		}
 	}()
 	return req, nil
@@ -817,7 +817,7 @@ func TestSkeletonSyncRetrievals(t *testing.T) {
 		dropped := make(map[string]int)
 		drop := func(peer string) {
 			if p := peerset.Peer(peer); p != nil {
-				atomic.AddUint64(&p.peer.(*skeletonTestPeer).dropped, 1)
+				p.peer.(*skeletonTestPeer).dropped.Add(1)
 			}
 			peerset.Unregister(peer)
 			dropped[peer]++
@@ -895,14 +895,14 @@ func TestSkeletonSyncRetrievals(t *testing.T) {
 		if !tt.unpredictable {
 			var served uint64
 			for _, peer := range tt.peers {
-				served += atomic.LoadUint64(&peer.served)
+				served += peer.served.Load()
 			}
 			if served != tt.midserve {
 				t.Errorf("test %d, mid state: served headers mismatch: have %d, want %d", i, served, tt.midserve)
 			}
 			var drops uint64
 			for _, peer := range tt.peers {
-				drops += atomic.LoadUint64(&peer.dropped)
+				drops += peer.dropped.Load()
 			}
 			if drops != tt.middrop {
 				t.Errorf("test %d, mid state: dropped peers mismatch: have %d, want %d", i, drops, tt.middrop)
@@ -950,20 +950,20 @@ func TestSkeletonSyncRetrievals(t *testing.T) {
 		if !tt.unpredictable {
 			served := uint64(0)
 			for _, peer := range tt.peers {
-				served += atomic.LoadUint64(&peer.served)
+				served += peer.served.Load()
 			}
 			if tt.newPeer != nil {
-				served += atomic.LoadUint64(&tt.newPeer.served)
+				served += tt.newPeer.served.Load()
 			}
 			if served != tt.endserve {
 				t.Errorf("test %d, end state: served headers mismatch: have %d, want %d", i, served, tt.endserve)
 			}
 			drops := uint64(0)
 			for _, peer := range tt.peers {
-				drops += atomic.LoadUint64(&peer.dropped)
+				drops += peer.dropped.Load()
 			}
 			if tt.newPeer != nil {
-				drops += atomic.LoadUint64(&tt.newPeer.dropped)
+				drops += tt.newPeer.dropped.Load()
 			}
 			if drops != tt.enddrop {
 				t.Errorf("test %d, end state: dropped peers mismatch: have %d, want %d", i, drops, tt.middrop)