refactor AccountEntry addref/unref (solana-labs#19583)

runtime/src/accounts_index.rs

@@ -114,9 +114,17 @@ pub struct AccountMapEntryInner<T> {
 }
 
 impl<T> AccountMapEntryInner<T> {
-    pub fn ref_count(&self) -> u64 {
+    pub fn ref_count(&self) -> RefCount {
         self.ref_count.load(Ordering::Relaxed)
     }
+
+    pub fn add_un_ref(&self, add: bool) {
+        if add {
+            self.ref_count.fetch_add(1, Ordering::Relaxed);
+        } else {
+            self.ref_count.fetch_sub(1, Ordering::Relaxed);
+        }
+    }
 }
 
 pub enum AccountIndexGetResult<'a, T: IsCached> {
@@ -153,19 +161,15 @@ impl<T: IsCached> ReadAccountMapEntry<T> {
     }
 
     pub fn ref_count(&self) -> RefCount {
-        self.borrow_owned_entry().ref_count.load(Ordering::Relaxed)
+        self.borrow_owned_entry().ref_count()
     }
 
     pub fn unref(&self) {
-        self.borrow_owned_entry()
-            .ref_count
-            .fetch_sub(1, Ordering::Relaxed);
+        self.borrow_owned_entry().add_un_ref(false);
     }
 
     pub fn addref(&self) {
-        self.borrow_owned_entry()
-            .ref_count
-            .fetch_add(1, Ordering::Relaxed);
+        self.borrow_owned_entry().add_un_ref(true);
     }
 }
 
@@ -213,10 +217,6 @@ impl<T: IsCached> WriteAccountMapEntry<T> {
         })
     }
 
-    fn addref(item: &AtomicU64) {
-        item.fetch_add(1, Ordering::Relaxed);
-    }
-
     pub fn upsert<'a>(
         mut w_account_maps: AccountMapsWriteLock<'a, T>,
         pubkey: &Pubkey,
@@ -278,7 +278,7 @@ impl<T: IsCached> WriteAccountMapEntry<T> {
             previous_slot_entry_was_cached,
         );
         if addref {
-            Self::addref(&current.ref_count);
+            current.add_un_ref(true);
         }
     }