f clearer comment, also dont bother spuriously waking

Author: TheBlueMatt

lightning/src/util/wakers.rs

@@ -94,13 +94,13 @@ impl Notifier {
 			future_probably_generated_calls |= Arc::strong_count(&future_state) > 1;
 		}
 		if !future_probably_generated_calls {
-			// If a future made some callbacks or still exists (i.e. the state has more than the
-			// one reference we hold), assume the user was notified and skip the "classic"
-			// waiters.
+			// If no future made any callbacks and has been drop'd (i.e. the state has only the one
+			// reference we hold), assume the user was not notified and set the
+			// notification-required flag. This will cause the `wait` functions above to return.
 			lock.0 = true;
 		}
 		mem::drop(lock);
-		self.condvar.notify_all();
+		if !future_probably_generated_calls { self.condvar.notify_all(); }
 	}
 
 	/// Gets a [`Future`] that will get woken up with any waiters