Part 11 of update fork choice - tracing and spans (#3285)

* Add tracing in forkchoice service

* Gazelle

beacon-chain/blockchain/forkchoice/BUILD.bazel

@@ -25,6 +25,7 @@ go_library(
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_prysmaticlabs_go_ssz//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
+        "@io_opencensus_go//trace:go_default_library",
     ],
 )
 

beacon-chain/blockchain/forkchoice/process_attestation.go

@@ -14,6 +14,7 @@ import (
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/hashutil"
 	"github.com/prysmaticlabs/prysm/shared/params"
+	"go.opencensus.io/trace"
 )
 
 // OnAttestation is called whenever an attestation is received, it updates validators latest vote,
@@ -50,6 +51,9 @@ import (
 //        if i not in store.latest_messages or target.epoch > store.latest_messages[i].epoch:
 //            store.latest_messages[i] = LatestMessage(epoch=target.epoch, root=attestation.data.beacon_block_root)
 func (s *Store) OnAttestation(ctx context.Context, a *ethpb.Attestation) error {
+	ctx, span := trace.StartSpan(ctx, "forkchoice.onAttestation")
+	defer span.End()
+
 	tgt := a.Data.Target
 	tgtSlot := helpers.StartSlot(tgt.Epoch)
 

beacon-chain/blockchain/forkchoice/process_block.go

@@ -14,6 +14,7 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/proto/eth/v1alpha1"
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/params"
+	"go.opencensus.io/trace"
 )
 
 // OnBlock is called whenever a block is received. It runs state transition on the block and
@@ -48,6 +49,9 @@ import (
 //    if state.finalized_checkpoint.epoch > store.finalized_checkpoint.epoch:
 //        store.finalized_checkpoint = state.finalized_checkpoint
 func (s *Store) OnBlock(ctx context.Context, b *ethpb.BeaconBlock) error {
+	ctx, span := trace.StartSpan(ctx, "forkchoice.onBlock")
+	defer span.End()
+
 	// Verify incoming block has a valid pre state.
 	preState, err := s.verifyBlkPreState(ctx, b)
 	if err != nil {

beacon-chain/blockchain/forkchoice/service.go

@@ -16,6 +16,7 @@ import (
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/hashutil"
 	"github.com/prysmaticlabs/prysm/shared/params"
+	"go.opencensus.io/trace"
 )
 
 // ForkChoicer defines a common interface for methods useful for directly applying fork choice
@@ -111,6 +112,9 @@ func (s *Store) GenesisStore(ctx context.Context, genesisState *pb.BeaconState)
 //    assert block.slot >= slot
 //    return root if block.slot == slot else get_ancestor(store, block.parent_root, slot)
 func (s *Store) ancestor(ctx context.Context, root []byte, slot uint64) ([]byte, error) {
+	ctx, span := trace.StartSpan(ctx, "forkchoice.ancestor")
+	defer span.End()
+
 	b, err := s.db.Block(ctx, bytesutil.ToBytes32(root))
 	if err != nil {
 		return nil, errors.Wrap(err, "could not get ancestor block")
@@ -141,6 +145,9 @@ func (s *Store) ancestor(ctx context.Context, root []byte, slot uint64) ([]byte,
 //            and get_ancestor(store, store.latest_messages[i].root, store.blocks[root].slot) == root)
 //    ))
 func (s *Store) latestAttestingBalance(ctx context.Context, root []byte) (uint64, error) {
+	ctx, span := trace.StartSpan(ctx, "forkchoice.latestAttestingBalance")
+	defer span.End()
+
 	s.lock.RLock()
 	defer s.lock.RUnlock()
 	h, err := hashutil.HashProto(s.justifiedCheckpt)
@@ -206,6 +213,9 @@ func (s *Store) latestAttestingBalance(ctx context.Context, root []byte) (uint64
 //        # Sort by latest attesting balance with ties broken lexicographically
 //        head = max(children, key=lambda root: (get_latest_attesting_balance(store, root), root))
 func (s *Store) Head(ctx context.Context) ([]byte, error) {
+	ctx, span := trace.StartSpan(ctx, "forkchoice.head")
+	defer span.End()
+
 	head := s.justifiedCheckpt.Root
 
 	for {