Check klist emptiness instead of NULL pointer in KNOTE()

All callers of KNOTE() supply a non-NULL klist argument. Replace the
NULL pointer check with klist emptiness check as a small optimization.

OK mpi@

diff --git a/sys/sys/event.h b/sys/sys/event.h
index 76272cc..eb00575 100644 (file)
--- a/sys/sys/event.h
+++ b/sys/sys/event.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: event.h,v 1.63 2022/02/11 07:25:50 visa Exp $ */
+/*     $OpenBSD: event.h,v 1.64 2022/02/11 07:27:07 visa Exp $ */
 
 /*-
  * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
@@ -154,7 +154,7 @@ struct klist {
 
 #define KNOTE(list, hint)      do { \
                                        struct klist *__list = (list); \
-                                       if (__list != NULL) \
+                                       if (!klist_empty(__list)) \
                                                knote(__list, hint); \
                                } while (0)