svn commit: r258576 - stable/8/sys/sys

[Andriy Gapon]

Author: avg
Date: Mon Nov 25 18:51:53 2013
New Revision: 258576
URL: http://svnweb.freebsd.org/changeset/base/258576

Log:
  MFC r240834: Add rounddown2() macro similar to the roundup2() macro.
  
  MFC slacker:	pjd

Modified:
  stable/8/sys/sys/param.h
Directory Properties:
  stable/8/sys/   (props changed)
  stable/8/sys/sys/   (props changed)

Modified: stable/8/sys/sys/param.h
==============================================================================
--- stable/8/sys/sys/param.h	Mon Nov 25 18:51:25 2013	(r258575)
+++ stable/8/sys/sys/param.h	Mon Nov 25 18:51:53 2013	(r258576)
@@ -273,6 +273,7 @@
 #endif
 #define	nitems(x)	(sizeof((x)) / sizeof((x)[0]))
 #define	rounddown(x, y)	(((x)/(y))*(y))
+#define	rounddown2(x, y) ((x)&(~((y)-1)))          /* if y is power of two */
 #define	roundup(x, y)	((((x)+((y)-1))/(y))*(y))  /* to any y */
 #define	roundup2(x, y)	(((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
 #define powerof2(x)	((((x)-1)&(x))==0)