[src/trunk]: src/sys Don't use __cmsg_alignbytes in the kernel. Mark it as co...

[joerg <joerg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/eb5a0f71be91
branches:  trunk
changeset: 772888:eb5a0f71be91
user:      joerg <joerg%NetBSD.org@localhost>
date:      Fri Jan 20 00:25:29 2012 +0000

description:
Don't use __cmsg_alignbytes in the kernel. Mark it as constant function
for userland as its value never changes. This allows the compiler to
optimise most invocations away.

diffstat:

 sys/lib/libkern/Makefile.libkern |   4 ++--
 sys/sys/socket.h                 |  11 ++++++++---
 2 files changed, 10 insertions(+), 5 deletions(-)

diffs (53 lines):

diff -r c3c4287da0ae -r eb5a0f71be91 sys/lib/libkern/Makefile.libkern
--- a/sys/lib/libkern/Makefile.libkern  Thu Jan 19 23:37:23 2012 +0000
+++ b/sys/lib/libkern/Makefile.libkern  Fri Jan 20 00:25:29 2012 +0000
@@ -1,4 +1,4 @@
-#      $NetBSD: Makefile.libkern,v 1.15 2011/11/19 22:51:25 tls Exp $
+#      $NetBSD: Makefile.libkern,v 1.16 2012/01/20 00:25:29 joerg Exp $
 
 # 
 # Variable definitions for libkern.  
@@ -58,7 +58,7 @@
 
 # Other stuff
 SRCS+= kern_assert.c __main.c
-SRCS+= __cmsg_alignbytes.c cpuset.c inet_addr.c intoa.c
+SRCS+= cpuset.c inet_addr.c intoa.c
 .if empty(SRCS:Mbyte_swap_8.*)
 SRCS+= bswap64.c
 .endif
diff -r c3c4287da0ae -r eb5a0f71be91 sys/sys/socket.h
--- a/sys/sys/socket.h  Thu Jan 19 23:37:23 2012 +0000
+++ b/sys/sys/socket.h  Fri Jan 20 00:25:29 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: socket.h,v 1.101 2011/12/20 23:56:29 christos Exp $    */
+/*     $NetBSD: socket.h,v 1.102 2012/01/20 00:25:29 joerg Exp $       */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -531,8 +531,11 @@
  * without (2), we can't guarantee binary compatibility in case of future
  * changes in ALIGNBYTES.
  */
+#ifdef _KERNEL
+#define __CMSG_ALIGN(n)        (((n) + ALIGNBYTES) & ~ALIGNBYTES)
+#define CMSG_ALIGN(n)  __CMSG_ALIGN(n)
+#else
 #define __CMSG_ALIGN(n)        (((n) + __cmsg_alignbytes()) & ~__cmsg_alignbytes())
-#ifdef _KERNEL
 #define CMSG_ALIGN(n)  __CMSG_ALIGN(n)
 #endif
 
@@ -574,9 +577,11 @@
 
 #include <sys/cdefs.h>
 
+#ifndef        _KERNEL
 __BEGIN_DECLS
-int    __cmsg_alignbytes(void);
+int    __cmsg_alignbytes(void) __constfunc;
 __END_DECLS
+#endif
 
 #ifdef _KERNEL
 static inline socklen_t