drop initiate validator ordering optimization

consensus/state_processing/src/common/initiate_validator_exit.rs

@@ -8,12 +8,12 @@ pub fn initiate_validator_exit<E: EthSpec>(
     index: usize,
     spec: &ChainSpec,
 ) -> Result<(), Error> {
-    // We do things in a slightly different order to the spec here. Instead of immediately checking
-    // whether the validator has already exited, we instead prepare the exit cache and compute the
-    // cheap-to-calculate values from that. *Then* we look up the validator a single time in the
-    // validator tree (expensive), make the check and mutate as appropriate. Compared to the spec
-    // ordering, this saves us from looking up the validator in the validator registry multiple
-    // times.
+    let validator = state.get_validator_cow(index)?;
+
+    // Return if the validator already initiated exit
+    if validator.exit_epoch != spec.far_future_epoch {
+        return Ok(());
+    }
 
     // Ensure the exit cache is built.
     state.build_exit_cache(spec)?;
@@ -36,14 +36,7 @@ pub fn initiate_validator_exit<E: EthSpec>(
         exit_queue_epoch
     };
 
-    let validator = state.get_validator_cow(index)?;
-
-    // Return if the validator already initiated exit
-    if validator.exit_epoch != spec.far_future_epoch {
-        return Ok(());
-    }
-
-    let validator = validator.into_mut()?;
+    let validator = state.get_validator_mut(index)?;
     validator.exit_epoch = exit_queue_epoch;
     validator.withdrawable_epoch =
         exit_queue_epoch.safe_add(spec.min_validator_withdrawability_delay)?;