Deneb PR feedback updates (#4716)

* move length update outside of if let in LRU cache

* add comment and use hex for G1_POINT_AT_INFINITY

* remove some misleading comments from `ssz_snappy`

* make sure we can't overflow on blobs by range requests with large counts

* downgrade gossip verification internal availability check error

* change blob rpc responses from BlockingFnWithManualSendOnIdle to BlockingFn

* remove unnecessary collect in blobs by range response

* add a comment to blobs by range response start slot logic

* typo persist_data_availabilty_checker -> persist_data_availability_checker

* unify cheap_state_advance_to_obtain_committees

beacon_node/network/src/network_beacon_processor/gossip_methods.rs

@@ -1186,7 +1186,7 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
                     | AvailabilityCheckError::MissingBlobs
                     | AvailabilityCheckError::StoreError(_)
                     | AvailabilityCheckError::DecodeError(_) => {
-                        crit!(
+                        warn!(
                             self.log,
                             "Internal availability check error";
                             "error" => ?err,

beacon_node/network/src/network_beacon_processor/mod.rs

@@ -562,9 +562,8 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
         request: BlobsByRangeRequest,
     ) -> Result<(), Error<T::EthSpec>> {
         let processor = self.clone();
-        let process_fn = move |send_idle_on_drop| {
-            processor.handle_blobs_by_range_request(send_idle_on_drop, peer_id, request_id, request)
-        };
+        let process_fn =
+            move || processor.handle_blobs_by_range_request(peer_id, request_id, request);
 
         self.try_send(BeaconWorkEvent {
             drop_during_sync: false,
@@ -580,9 +579,8 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
         request: BlobsByRootRequest,
     ) -> Result<(), Error<T::EthSpec>> {
         let processor = self.clone();
-        let process_fn = move |send_idle_on_drop| {
-            processor.handle_blobs_by_root_request(send_idle_on_drop, peer_id, request_id, request)
-        };
+        let process_fn =
+            move || processor.handle_blobs_by_root_request(peer_id, request_id, request);
 
         self.try_send(BeaconWorkEvent {
             drop_during_sync: false,

beacon_node/network/src/network_beacon_processor/rpc_methods.rs

@@ -220,7 +220,6 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
     /// Handle a `BlobsByRoot` request from the peer.
     pub fn handle_blobs_by_root_request(
         self: Arc<Self>,
-        send_on_drop: SendOnDrop,
         peer_id: PeerId,
         request_id: PeerRequestId,
         request: BlobsByRootRequest,
@@ -286,7 +285,6 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
         if send_response {
             self.send_response(peer_id, Response::BlobsByRoot(None), request_id);
         }
-        drop(send_on_drop);
     }
 
     /// Handle a `BlocksByRoot` request from the peer.
@@ -607,7 +605,6 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
     /// Handle a `BlobsByRange` request from the peer.
     pub fn handle_blobs_by_range_request(
         self: Arc<Self>,
-        send_on_drop: SendOnDrop,
         peer_id: PeerId,
         request_id: PeerRequestId,
         req: BlobsByRangeRequest,
@@ -619,7 +616,7 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
         );
 
         // Should not send more than max request blocks
-        if req.count * T::EthSpec::max_blobs_per_block() as u64 > MAX_REQUEST_BLOB_SIDECARS {
+        if req.max_blobs_requested::<T::EthSpec>() > MAX_REQUEST_BLOB_SIDECARS {
             return self.send_error_response(
                 peer_id,
                 RPCResponseErrorCode::InvalidRequest,
@@ -711,13 +708,16 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
                 }
             };
 
-        // Pick out the required blocks, ignoring skip-slots.
+        // Use `WhenSlotSkipped::Prev` to get the most recent block root prior to
+        // `request_start_slot` in order to check whether the `request_start_slot` is a skip.
         let mut last_block_root = req.start_slot.checked_sub(1).and_then(|prev_slot| {
             self.chain
                 .block_root_at_slot(Slot::new(prev_slot), WhenSlotSkipped::Prev)
                 .ok()
                 .flatten()
         });
+
+        // Pick out the required blocks, ignoring skip-slots.
         let maybe_block_roots = process_results(forwards_block_root_iter, |iter| {
             iter.take_while(|(_, slot)| slot.as_u64() < req.start_slot.saturating_add(req.count))
                 // map skip slots to None
@@ -745,7 +745,7 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
         };
 
         // remove all skip slots
-        let block_roots = block_roots.into_iter().flatten().collect::<Vec<_>>();
+        let block_roots = block_roots.into_iter().flatten();
 
         let mut blobs_sent = 0;
         let mut send_response = true;
@@ -806,7 +806,5 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
                 id: request_id,
             });
         }
-
-        drop(send_on_drop);
     }
 }