Fix initialization race (#12374)

* block all the sync startup code on init signal

* don't need chainStarted if everything blocks

* set empty clock by default to work around panics

* remove unused clock, zero-value for init-sync

---------

Co-authored-by: Kasey Kirkham <kasey@users.noreply.github.com>
Co-authored-by: Nishant Das <nishdas93@gmail.com>

beacon-chain/sync/initial-sync/blocks_fetcher.go

@@ -11,7 +11,6 @@ import (
 	"github.com/prysmaticlabs/prysm/v4/beacon-chain/db"
 	"github.com/prysmaticlabs/prysm/v4/beacon-chain/p2p"
 	p2pTypes "github.com/prysmaticlabs/prysm/v4/beacon-chain/p2p/types"
-	"github.com/prysmaticlabs/prysm/v4/beacon-chain/startup"
 	prysmsync "github.com/prysmaticlabs/prysm/v4/beacon-chain/sync"
 	"github.com/prysmaticlabs/prysm/v4/cmd/beacon-chain/flags"
 	"github.com/prysmaticlabs/prysm/v4/config/params"
@@ -87,7 +86,6 @@ type blocksFetcher struct {
 	capacityWeight  float64       // how remaining capacity affects peer selection
 	mode            syncMode      // allows to use fetcher in different sync scenarios
 	quit            chan struct{} // termination notifier
-	clock           *startup.Clock
 }
 
 // peerLock restricts fetcher actions on per peer basis. Currently, used for rate limiting.

beacon-chain/sync/initial-sync/blocks_fetcher_test.go

@@ -552,7 +552,6 @@ func TestBlocksFetcher_RequestBlocksRateLimitingLocks(t *testing.T) {
 	gt := time.Now()
 	vr := [32]byte{}
 	fetcher.chain = &mock.ChainService{Genesis: gt, ValidatorsRoot: vr}
-	fetcher.clock = startup.NewClock(gt, vr)
 	hook := logTest.NewGlobal()
 	wg := new(sync.WaitGroup)
 	wg.Add(1)
@@ -621,7 +620,6 @@ func TestBlocksFetcher_WaitForBandwidth(t *testing.T) {
 	gt := time.Now()
 	vr := [32]byte{}
 	fetcher.chain = &mock.ChainService{Genesis: gt, ValidatorsRoot: vr}
-	fetcher.clock = startup.NewClock(gt, vr)
 	start := time.Now()
 	assert.NoError(t, fetcher.waitForBandwidth(p2.PeerID(), 10))
 	dur := time.Since(start)

beacon-chain/sync/initial-sync/service.go

@@ -67,6 +67,7 @@ func NewService(ctx context.Context, cfg *Config) *Service {
 		chainStarted: abool.New(),
 		counter:      ratecounter.NewRateCounter(counterSeconds * time.Second),
 		genesisChan:  make(chan time.Time),
+		clock:        startup.NewClock(time.Unix(0, 0), [32]byte{}), // default clock to prevent panic
 	}
 
 	return s

beacon-chain/sync/service.go

@@ -150,7 +150,7 @@ func NewService(ctx context.Context, opts ...Option) *Service {
 		ctx:                  ctx,
 		cancel:               cancel,
 		chainStarted:         abool.New(),
-		cfg:                  &config{},
+		cfg:                  &config{clock: startup.NewClock(time.Unix(0, 0), [32]byte{})},
 		slotToPendingBlocks:  c,
 		seenPendingBlocks:    make(map[[32]byte]bool),
 		blkRootToPendingAtts: make(map[[32]byte][]*ethpb.SignedAggregateAttestationAndProof),