From 3f3f6bc302d58a8deed268038eab908025ae724a Mon Sep 17 00:00:00 2001
From: Ed Schouten <ed@FreeBSD.org>
Date: Tue, 8 Nov 2011 15:38:21 +0000
Subject: [PATCH] Make kobj_methods constant.

These structures hold no information that is modified during runtime. By
marking this constant, we see approximately 600 symbols become
read-only (amd64 GENERIC). While there, also mark the kobj_method
structures generated by makeobjops.awk static. They are only referenced
by the kobjop_desc structures within the same file.

Before:

	$ ls -l kernel
	-rwxr-xr-x  1 ed  wheel  15937309 Nov  8 16:29 kernel*
	$ size kernel
	    text    data     bss      dec    hex filename
	12260854 1358468 2848832 16468154 fb48ba kernel
	$ nm kernel | fgrep -c ' r '
	8240

After:

	$ ls -l kernel
	-rwxr-xr-x  1 ed  wheel  15922469 Nov  8 16:25 kernel*
	$ size kernel
	    text    data     bss      dec    hex filename
	12302869 1302660 2848704 16454233 fb1259 kernel
	$ nm kernel | fgrep -c ' r '
	8838
---
 sys/kern/subr_kobj.c     | 2 +-
 sys/sys/kobj.h           | 2 +-
 sys/tools/makeobjops.awk | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/sys/kern/subr_kobj.c b/sys/kern/subr_kobj.c
index 4ee71824fa7..23ad29f7c17 100644
--- a/sys/kern/subr_kobj.c
+++ b/sys/kern/subr_kobj.c
@@ -92,7 +92,7 @@ SYSINIT(kobj, SI_SUB_LOCK, SI_ORDER_ANY, kobj_init_mutex, NULL);
  * desc pointer is NULL, it is guaranteed never to match any read
  * descriptors.
  */
-static struct kobj_method null_method = {
+static const struct kobj_method null_method = {
 	0, 0,
 };
 
diff --git a/sys/sys/kobj.h b/sys/sys/kobj.h
index 3143bea4290..31d308a4bf5 100644
--- a/sys/sys/kobj.h
+++ b/sys/sys/kobj.h
@@ -34,7 +34,7 @@
  */
 typedef struct kobj		*kobj_t;
 typedef struct kobj_class	*kobj_class_t;
-typedef struct kobj_method	kobj_method_t;
+typedef const struct kobj_method kobj_method_t;
 typedef int			(*kobjop_t)(void);
 typedef struct kobj_ops		*kobj_ops_t;
 typedef struct kobjop_desc	*kobjop_desc_t;
diff --git a/sys/tools/makeobjops.awk b/sys/tools/makeobjops.awk
index 0406b855047..4e3bd0485d2 100644
--- a/sys/tools/makeobjops.awk
+++ b/sys/tools/makeobjops.awk
@@ -307,7 +307,7 @@ function handle_method (static, doc)
 	    line_width, length(prototype)));
 
 	# Print out the method desc
-	printc("struct kobj_method " mname "_method_default = {");
+	printc("static const struct kobj_method " mname "_method_default = {");
 	printc("\t&" mname "_desc, (kobjop_t) " default_function);
 	printc("};\n");