Re: [RFC] CONFIG_TINY

Re: [RFC] CONFIG_TINY

[Joe Perches]

On Wed, 2002-10-23 at 15:51, Rasmus Andersen wrote:
> o reduce usage of prinkt in kernel by #defining iprintk for
>   INFO messages etc and let the desired (minimum) logging 
>   level be decided at compile time.

kernel.h already has #defines for pr_debug and pr_info.
perhaps all 8 current KERN_xxx's could be pr_#define'd
and the printks converted during 2.7+

I think this should be done together with Larry Kessler's
kernel logging proposal.

[RFC] CONFIG_TINY

[Rasmus Andersen]

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Hi,

Inspired by the recent lowmem threads on l-k and in loose
conjunction with acme, I am trying to do a CONFIG_TINY
patchset which would reduce the kernel image size and memory
footprint. Below is my list of ideas, collected from the
aforementioned threads and from acme's input. Note that some
of these are already being persued by other people (notably
[by me] Andrew Morton).

Not all, if any, of this will ever be fit to go into the
kernel proper. This is fine, since that is not the primary
purpose for me right now.  Starting off, the idea is to
explore whether certain things are doable or not and what
their actual payoffs are. From there cleanliness will be
considered. I expect to learn as I go, tying neatly into the
'cleanliness later' approach :)

Nevertheless, some of these are also painful enough that I
won't do them if directly told that they never will makes it
into the kernel (the printk and __initstr changes comes to
mind here) (acme, I think you wrote that you had gotten
encouraging noises from linus on the __initstr one?)

The purpose of this mail is to get feedback in form of further
areas where kernel size could be reduced, to learn if others
are looking at some of these points and to see if I get some
of the aforementioned 'never going to make it' noises.

Anyway, the list, terse form (there is no other):

Compile time:
o acme's __initstr (mark strings from __init functions as
  __initdata).
o reduce usage of prinkt in kernel by #defining iprintk for
  INFO messages etc and let the desired (minimum) logging 
  level be decided at compile time.
o configure out #! exec stuff (Mentioned by Alan Cox in the
  'end of embedded linux' thread).
o configure out procfs in ide (arjan's CONFIG_SMALL from
  redhat kernels) (I might have missed the point here, I
  only inspected briefly). Make procfs configurable for the
  IDE subsystem?
o reduce usage of inlines in the kernel. (Andrew Morton has
  an old patch I need to play a bit more with).
o SWAP and BLOCK_DEV as modules

Runtime:
o vfsmounts hash reduced to one page
o TCP(networking?) hashes reduced
o mempools reduced (Andrew Morton seems to be attacking this)



I have made a few crude, preliminary stabs at patches for some
of the above against 2.5.43, applies against 44 as well. The noswap
and noinline ones have been boot tested, the printk one compile
tested. Comments welcome:

Config is 'allnoconfig', base kernel size is

   text    data     bss     dec     hex filename
 478401   50720  254816  783937   bf641 vmlinux



No swap: I stubbed out all swap calls in mm/ by jackhammer.
New kernel size:

   text    data     bss     dec     hex filename
 469133   50433  252192  771758   bc6ae vmlinux

(Patch at www.jaquet.dk/kernel/config_tiny/2.5.43-noswap)



printk: So far I have defined {i,d,n,w}prink corresponding to
KERN_ {INFO,DEBUG,NOTICE,WARNING} and have converted files to
use this. Higher levels are left untouched.

Comments:
 1) It may seem inconsistent to have iprintk("Fine day today")
    followed by printk(KERN_CRIT "Aiee. Drive on fire!!"). But
    converting _all_ printks seems quite intrusive. Or I am just
    waffling here?
 2) The WARNING level is included in this cleanup since it is
    the default log level and lots of places dont specify a
    log level. If higher log levels are not converted to this
    printk format, it might make sense to make these places
    use KERN_WARNING instead of letting these be configured
    away at compile time?
 3) The current names are short. However, the dprintk is
    troublesome for obvious reasons. Currently, I am using
    raa_printk :) but that would change. printk_info etc
    have been suggested as an alternative.

File touched so far is kernel/*, init/*, fs/*, ipc/*, mm/* and
kernel.h (where I stuck the #defines).
New kernel size:

   text    data     bss     dec     hex filename
 478109   50337  254560  783006   bf29e vmlinux   (woo! :)

(Patch at www.jaquet.dk/kernel/config_tiny/2.5.43-printk)



Reduce inlines: This is an old patch I got from Andrew Morton,
eliminating some inlines in fs/, mm/, kernel/ and lib/. So far 
I have only brought it forward to 2.5.43, I plan to do a more
aggressive version soon.

   text    data     bss     dec     hex filename
 474129   50720  254816  779665   be591 vmlinux

(Patch at www.jaquet.dk/kernel/config_tiny/2.5.43-noinlines)


Your comments will be appreciated.

Regards,
  Rasmus

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Re: [RFC] CONFIG_TINY

[Christoph Hellwig]

On Wed, Oct 23, 2002 at 09:51:17PM +0200, Rasmus Andersen wrote:
> o SWAP and BLOCK_DEV as modules

modules won't work I guess :)  but allowing to disable them is a good
idea.  Not that swap depends on the block device code, though.

I have implemented CONFIG_SWAP for the uClinux patches, but there are
still some small bits missing to allow CONFIG_MMU && !CONFIG_SWAP

> o vfsmounts hash reduced to one page

Should be made smaller unconditionally, IMHO.

Re: [RFC] CONFIG_TINY

[Rasmus Andersen]

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On Wed, Oct 23, 2002 at 09:08:45PM +0100, Christoph Hellwig wrote:
> On Wed, Oct 23, 2002 at 09:51:17PM +0200, Rasmus Andersen wrote:
> > o SWAP and BLOCK_DEV as modules
> 
> modules won't work I guess :)  but allowing to disable them is a good
> idea.  Not that swap depends on the block device code, though.

The module approach was just a happy thought jotted down from an
IRC log. I guess there is a number of reasons that that won't 
work. 

I did not meant to imply that SWAP and block was related, just
that both (perhaph) could be made modules.

Thanks for your comments,
  Rasmus

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Re: [RFC] CONFIG_TINY

[Elladan]

On Wed, Oct 23, 2002 at 09:51:17PM +0200, Rasmus Andersen wrote:
> Hi,
> 
> Inspired by the recent lowmem threads on l-k and in loose
> conjunction with acme, I am trying to do a CONFIG_TINY
> patchset which would reduce the kernel image size and memory
> footprint. Below is my list of ideas, collected from the
> aforementioned threads and from acme's input. Note that some
> of these are already being persued by other people (notably
> [by me] Andrew Morton).
> 
> [...]
>
> o reduce usage of prinkt in kernel by #defining iprintk for
>   INFO messages etc and let the desired (minimum) logging 
>   level be decided at compile time.

Instead of doing it this way, why not use a preprocessor scheme like
this one which doesn't require you to patch anything (my apologies for
it being somewhat obtuse):

#define DBG_LVL 1
#define UNTAGGED_DBG_LVL 0

#define KERN_MSG_LVL 5
#define KERN_MSG_STRING "<5>"


#define printk(a, arg...) do { \
        { \
		if(DBG_LVL < UNTAGGED_DBG_LVL) \
			switch(UNTAGGED_DBG_LVL) { \
				default: \
					_printk("" a, ##arg); \
			} \
		} \
	} while(0)

#define KERN_WARNING 				); \
				case UNTAGGED_DBG_LVL: \
			} \
			if(DBG_LVL < KERN_MSG_LVL) { \
				_printk(KERN_MSG_STRING


(Yes, I enjoyed writing these macros)

The strings themselves will still be included, but you should be able to
run a string pruning program on the output objects since there is no
longer any reference to them at all.

Does this make more sense?  Maintaining a patch that changes all the
printks in the world is going to hurt!

-J

Re: [RFC] CONFIG_TINY

[Rasmus Andersen]

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On Wed, Oct 23, 2002 at 09:51:17PM +0200, Rasmus Andersen wrote:
> printk: So far I have defined {i,d,n,w}prink corresponding to
> KERN_ {INFO,DEBUG,NOTICE,WARNING} and have converted files to
> use this. Higher levels are left untouched.
> 
[...]
> 
>    text    data     bss     dec     hex filename
>  478109   50337  254560  783006   bf29e vmlinux   (woo! :)
> 
> (Patch at www.jaquet.dk/kernel/config_tiny/2.5.43-printk)

Memo to me: Dont use the kernel compiled to check #define
correctness for enabling printk output to measure the kernel
size when prinkt is disabled. New, better kernel size:

   text    data     bss     dec     hex filename
 475629   50913  252512  779054   be32e vmlinux


Regards, 
  Rasmus

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Re: [RFC] CONFIG_TINY

[Rasmus Andersen]

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On Wed, Oct 23, 2002 at 01:11:58PM -0400, Joe Perches wrote:
> kernel.h already has #defines for pr_debug and pr_info.
> perhaps all 8 current KERN_xxx's could be pr_#define'd
> and the printks converted during 2.7+

Possibly. Certainly fine by me.

> I think this should be done together with Larry Kessler's
> kernel logging proposal.

I only followed this discussion superficially. Would you mind
providing a link for the thread or giving me a short roundup
of the conclusion on that?

Thanks,
  Rasmus

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Untested patch 1/2 - add ugly printk macros to kernel (was Re: [RFC] CONFIG_TINY)

[Elladan]

Here is an untested patch example against 2.5.44 to add some ugly printk
macros to the kernel, to reduce kernel image size for tiny systems.

I verified that this builds a kernel image on my system (if I fix some
2.5.44 build failures, obviously), with the fixup patch I'm sending next
to modify some of the sources for the new printk style.

This patch is hardly complete, and is just an example of using macros to
selectively cut out printk string/code bloat from the kernel.  By
changing the TAG_PRINTK_LVL and UNTAG_PRINTK_LVL numbers, selective
levels of printks can be compiled out of the kernel.

With my config and gcc-3.1 (which has dead-string pruning), I got these
build-size numbers with different TAG_PRINTK values:

Define printk like normal (#define printk(a,arg...) _printk(a, ##arg))
System is 1093 kB

All levels on (7 TAG/7 UNTAG)
System is 1090 kB (3k less, not sure why)

Only tagged warning or above (4/7)
System is 1024 kB

Only tagged alert or above (1/7)
System is 1002 kB

Only tagged emergency (0/7)
System is 1002 kB

All printk off (-1/7)
System is 997 kB

Kill printk completely (#define printk(a...) 0)
System is 997 kB


There are several obvious problems with this implementation:

* The KERN_ERR etc. macros can't work in all situations, since they are
  no longer simple strings.  The second patch fixes some of these
  situations.
* Changing the printk symbol to be _printk is probably a bad idea.  It
  would be best to keep the symbol name the same in a real
  implementation.
* It's somewhat hard to read.

Comments?

-J

--- include/linux/kernel.h-orig	2002-10-24 18:20:16.000000000 -0700
+++ include/linux/kernel.h	2002-10-24 18:23:36.000000000 -0700
@@ -13,6 +13,7 @@
 #include <linux/types.h>
 #include <linux/compiler.h>
 #include <asm/byteorder.h>
+#include <linux/printk.h>
 
 /* Optimization barrier */
 /* The "volatile" is due to gcc bugs */
@@ -29,15 +30,6 @@
 
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 
-#define	KERN_EMERG	"<0>"	/* system is unusable			*/
-#define	KERN_ALERT	"<1>"	/* action must be taken immediately	*/
-#define	KERN_CRIT	"<2>"	/* critical conditions			*/
-#define	KERN_ERR	"<3>"	/* error conditions			*/
-#define	KERN_WARNING	"<4>"	/* warning conditions			*/
-#define	KERN_NOTICE	"<5>"	/* normal but significant condition	*/
-#define	KERN_INFO	"<6>"	/* informational			*/
-#define	KERN_DEBUG	"<7>"	/* debug-level messages			*/
-
 struct completion;
 
 #ifdef CONFIG_DEBUG_KERNEL
@@ -78,9 +70,6 @@
 
 extern int session_of_pgrp(int pgrp);
 
-asmlinkage int printk(const char * fmt, ...)
-	__attribute__ ((format (printf, 1, 2)));
-
 extern int console_loglevel;
 
 static inline void console_silent(void)
--- kernel/printk.c-orig	2002-10-24 18:57:06.000000000 -0700
+++ kernel/printk.c	2002-10-24 18:57:40.000000000 -0700
@@ -296,7 +296,7 @@
 		if (copy_from_user(lbuf, buf, len))
 			break;
 		lbuf[len] = '\0';
-		error = printk("%s", lbuf);
+		error = _printk("%s", lbuf);
 		break;
 	default:
 		error = -EINVAL;
@@ -419,7 +419,7 @@
  * then changes console_loglevel may break. This is because console_loglevel
  * is inspected when the actual printing occurs.
  */
-asmlinkage int printk(const char *fmt, ...)
+asmlinkage int _printk(const char *fmt, ...)
 {
 	va_list args;
 	unsigned long flags;
@@ -488,7 +488,7 @@
 out:
 	return printed_len;
 }
-EXPORT_SYMBOL(printk);
+EXPORT_SYMBOL(_printk);
 
 /**
  * acquire_console_sem - lock the console system for exclusive use.
--- /dev/null	2002-07-27 00:29:01.000000000 -0700
+++ include/linux/printk.h	2002-10-24 21:33:01.000000000 -0700
@@ -0,0 +1,150 @@
+#ifndef _LINUX_PRINTK_H
+#define _LINUX_PRINTK_H
+
+/*
+ * 'printk.h' contains some scary macros implementing compile-time
+ * selectable warning levels.
+ */
+
+#ifdef __KERNEL__
+
+#include <stdarg.h>
+#include <linux/linkage.h>
+
+/* Actual prepend strings */
+#define	KERN_EMERG_STR	 "<0>"	/* system is unusable			*/
+#define	KERN_ALERT_STR	 "<1>"	/* action must be taken immediately	*/
+#define	KERN_CRIT_STR	 "<2>"	/* critical conditions			*/
+#define	KERN_ERR_STR	 "<3>"	/* error conditions			*/
+#define	KERN_WARNING_STR "<4>"	/* warning conditions			*/
+#define	KERN_NOTICE_STR	 "<5>"	/* normal but significant condition	*/
+#define	KERN_INFO_STR	 "<6>"	/* informational			*/
+#define	KERN_DEBUG_STR	 "<7>"	/* debug-level messages			*/
+
+#define	KERN_EMERG_LVL	 0
+#define	KERN_ALERT_LVL	 1
+#define	KERN_CRIT_LVL	 2
+#define	KERN_ERR_LVL	 3
+#define	KERN_WARNING_LVL 4
+#define	KERN_NOTICE_LVL	 5
+#define	KERN_INFO_LVL	 6
+#define	KERN_DEBUG_LVL	 7
+
+#if 1
+
+/* The operation of these macros is somewhat obscure.  Basically, we
+ * depend on the optimizing compiler being able to remove branches
+ * that can never be followed because the expression is constant
+ * false.
+ *
+ * TAG_PRINTK_LVL and UNTAG_PRINTK_LVL may be changed at build time,
+ * allowing the user to compile printk statements below the listed
+ * level out completely.
+ *
+ * By default, they always succeed, so these macros should be (more or less)
+ * equivalent to standard printk calls.
+ *
+ * A possible problem on older versions of GCC is that, even if turned
+ * off, the actual strings may still be included in the object file.
+ */
+
+#if !defined(TAG_PRINTK_LVL)
+# define TAG_PRINTK_LVL 7
+#endif
+
+#if !defined(UNTAG_PRINTK_LVL)
+# define UNTAG_PRINTK_LVL 7
+#endif
+
+/* The trick here is that the a argument may be replaced by a KERN_
+ * macro, which will cause the UNTAG switch statement to disable itself.
+ * The kern macro will then place the proper level-based code in its own
+ * if statement.
+ */
+extern const char *__broken_printk_call;
+
+#define printk(a, arg...) ({ \
+	{ \
+		int ret;\
+		if(TAG_PRINTK_LVL >= UNTAG_PRINTK_LVL) \
+			switch(UNTAG_PRINTK_LVL) { \
+			default: \
+				ret = _printk(0+ a, ##arg); \
+			} \
+		ret; \
+	} \
+}) 
+
+#define KERN_EMERG __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_EMERG_LVL) { \
+			ret = _printk(KERN_EMERG_STR
+
+#define KERN_ALERT __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_ALERT_LVL) { \
+			_printk(KERN_ALERT_STR
+
+#define KERN_CRIT __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_CRIT_LVL) { \
+			_printk(KERN_CRIT_STR
+
+#define KERN_ERR __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_ERR_LVL) { \
+			_printk(KERN_ERR_STR
+
+#define KERN_WARNING __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_WARNING_LVL) { \
+			_printk(KERN_WARNING_STR
+
+#define KERN_NOTICE __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_NOTICE_LVL) { \
+			_printk(KERN_NOTICE_STR
+
+#define KERN_INFO __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_INFO_LVL) { \
+			_printk(KERN_INFO_STR
+
+#define KERN_DEBUG __broken_printk_call); \
+			case UNTAG_PRINTK_LVL: \
+			ret = 0; \
+			} \
+		if(TAG_PRINTK_LVL >= KERN_DEBUG_LVL) { \
+			_printk(KERN_DEBUG_STR
+#else
+#define printk(a, arg...) _printk(a, ##arg)
+#define	KERN_EMERG	KERN_EMERG_STR
+#define	KERN_ALERT	KERN_ALERT_STR
+#define	KERN_CRIT	KERN_CRIT_STR
+#define	KERN_ERR	KERN_ERR_STR
+#define	KERN_WARNING 	KERN_WARNING_STR
+#define	KERN_NOTICE	KERN_NOTICE_STR
+#define	KERN_INFO	KERN_INFO_STR
+#define	KERN_DEBUG	KERN_DEBUG_STR
+#endif
+
+asmlinkage int _printk(const char * fmt, ...)
+	__attribute__ ((format (printf, 1, 2)));
+
+#endif /* __KERNEL__ */
+
+#endif

Untested patch 2/2 - Fix some kernel sources for macro printk (was Re: [RFC] CONFIG_TINY)

[Elladan]

The previous patch added some complex, ugly macros to replace printk()
in the kernel in a way which allows printk() calls to be selectively
disabled at compile time.  These macros cannot work in all situations,
because some parts of the kernel depend on eg. KERN_ERR actually being a
simple string.  

This patch modifies certain kernel sources to fix this.  It either
removes the dependency, or changes these places to use a new
KERN_ERR_STR etc. macro.

This is not at all a complete patch - it was just the minimal change
required to get the core kernel to build with my own particular
configuration.  I'm only including it since the previous patch doesn't
build at all without it.

-J


--- kernel/module.c-orig	2002-10-24 18:59:02.000000000 -0700
+++ kernel/module.c	2002-10-24 18:59:09.000000000 -0700
@@ -379,8 +379,8 @@
 		goto err1;
 	if (mod_user_size < (unsigned long)&((struct module *)0L)->persist_start
 	    || mod_user_size > sizeof(struct module) + 16*sizeof(void*)) {
-		printk(KERN_ERR "init_module: Invalid module header size.\n"
-		       KERN_ERR "A new version of the modutils is likely "
+		printk(KERN_ERR     "init_module: Invalid module header size.\n"
+		       KERN_ERR_STR "A new version of the modutils is likely "
 				"needed.\n");
 		error = -EINVAL;
 		goto err1;
--- mm/slab.c-orig	2002-10-24 19:02:28.000000000 -0700
+++ mm/slab.c	2002-10-24 19:02:39.000000000 -0700
@@ -658,7 +658,7 @@
 	unsigned long flags, void (*ctor)(void*, kmem_cache_t *, unsigned long),
 	void (*dtor)(void*, kmem_cache_t *, unsigned long))
 {
-	const char *func_nm = KERN_ERR "kmem_create: ";
+	const char *func_nm = "kmem_create: ";
 	size_t left_over, align, slab_size;
 	kmem_cache_t *cachep = NULL;
 
@@ -676,13 +676,13 @@
 #if DEBUG
 	if ((flags & SLAB_DEBUG_INITIAL) && !ctor) {
 		/* No constructor, but inital state check requested */
-		printk("%sNo con, but init state check requested - %s\n", func_nm, name);
+		printk(KERN_ERR "%sNo con, but init state check requested - %s\n", func_nm, name);
 		flags &= ~SLAB_DEBUG_INITIAL;
 	}
 
 	if ((flags & SLAB_POISON) && ctor) {
 		/* request for poisoning, but we can't do that with a constructor */
-		printk("%sPoisoning requested, but con given - %s\n", func_nm, name);
+		printk(KERN_ERR "%sPoisoning requested, but con given - %s\n", func_nm, name);
 		flags &= ~SLAB_POISON;
 	}
 #if FORCED_DEBUG
@@ -717,7 +717,7 @@
 	if (size & (BYTES_PER_WORD-1)) {
 		size += (BYTES_PER_WORD-1);
 		size &= ~(BYTES_PER_WORD-1);
-		printk("%sForcing size word alignment - %s\n", func_nm, name);
+		printk(KERN_ERR "%sForcing size word alignment - %s\n", func_nm, name);
 	}
 	
 #if DEBUG
@@ -788,7 +788,7 @@
 	} while (1);
 
 	if (!cachep->num) {
-		printk("kmem_cache_create: couldn't create cache %s.\n", name);
+		printk(KERN_ERR "kmem_cache_create: couldn't create cache %s.\n", name);
 		kmem_cache_free(&cache_cache, cachep);
 		cachep = NULL;
 		goto opps;
--- drivers/md/md.c-orig	2002-10-24 19:07:52.000000000 -0700
+++ drivers/md/md.c	2002-10-24 19:12:17.000000000 -0700
@@ -56,7 +56,7 @@
 #include <linux/blk.h>
 
 #define DEBUG 0
-#define dprintk(x...) ((void)(DEBUG && printk(x)))
+#define dprintk(x...) do { if(DEBUG) printk(x); } while(0)
 
 
 #ifndef MODULE
@@ -2977,7 +2977,7 @@
 	struct list_head *tmp, *rtmp;
 
 
-	dprintk(KERN_INFO "md: recovery thread got woken up ...\n");
+	dprintk(KERN_INFO_STR "md: recovery thread got woken up ...\n");
 
 	ITERATE_MDDEV(mddev,tmp) if (mddev_lock(mddev)==0) {
 		if (!mddev->raid_disks || !mddev->pers || mddev->ro)
@@ -3054,7 +3054,7 @@
 	unlock:
 		mddev_unlock(mddev);
 	}
-	dprintk(KERN_INFO "md: recovery thread finished ...\n");
+	dprintk(KERN_INFO_STR "md: recovery thread finished ...\n");
 
 }
 
--- drivers/char/tty_io.c-orig	2002-10-24 19:06:14.000000000 -0700
+++ drivers/char/tty_io.c	2002-10-24 19:07:10.000000000 -0700
@@ -212,9 +212,9 @@
 			      const char *routine)
 {
 #ifdef TTY_PARANOIA_CHECK
-	static const char badmagic[] = KERN_WARNING
+	static const char badmagic[] = KERN_WARNING_STR
 		"Warning: bad magic number for tty struct (%s) in %s\n";
-	static const char badtty[] = KERN_WARNING
+	static const char badtty[] = KERN_WARNING_STR
 		"Warning: null TTY for (%s) in %s\n";
 
 	if (!tty) {
--- drivers/block/floppy.c-orig	2002-10-24 19:04:29.000000000 -0700
+++ drivers/block/floppy.c	2002-10-24 19:05:46.000000000 -0700
@@ -3653,7 +3653,7 @@
 		if (name) {
 			const char * prepend = ",";
 			if (first) {
-				prepend = KERN_INFO "Floppy drive(s):";
+				prepend = KERN_INFO_STR "Floppy drive(s):";
 				first = 0;
 			}
 			printk("%s fd%d is %s", prepend, drive, name);
--- net/sunrpc/sched.c-orig	2002-10-24 19:41:21.000000000 -0700
+++ net/sunrpc/sched.c	2002-10-24 19:41:35.000000000 -0700
@@ -338,7 +338,7 @@
 	} else {
 		rpc_clear_running(task);
 		if (task->tk_callback) {
-			dprintk(KERN_ERR "RPC: %4d overwrites an active callback\n", task->tk_pid);
+			dprintk(KERN_ERR_STR "RPC: %4d overwrites an active callback\n", task->tk_pid);
 			BUG();
 		}
 		task->tk_callback = action;
--- net/sunrpc/clnt.c-orig	2002-10-24 19:35:53.000000000 -0700
+++ net/sunrpc/clnt.c	2002-10-24 19:39:59.000000000 -0700
@@ -909,7 +909,7 @@
 	task->tk_client->cl_stats->rpcgarbage++;
 	if (task->tk_garb_retry) {
 		task->tk_garb_retry--;
-		dprintk(KERN_WARNING "RPC: garbage, retrying %4d\n", task->tk_pid);
+		dprintk(KERN_WARNING_STR "RPC: garbage, retrying %4d\n", task->tk_pid);
 		task->tk_action = call_encode;
 		return NULL;
 	}
--- net/sunrpc/svcsock.c-orig	2002-10-24 19:41:56.000000000 -0700
+++ net/sunrpc/svcsock.c	2002-10-24 19:42:31.000000000 -0700
@@ -715,7 +715,7 @@
 	 * tell us anything. For now just warn about unpriv connections.
 	 */
 	if (ntohs(sin.sin_port) >= 1024) {
-		dprintk(KERN_WARNING
+		dprintk(KERN_WARNING_STR
 			"%s: connect from unprivileged port: %u.%u.%u.%u:%d\n",
 			serv->sv_name, 
 			NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port));
@@ -1304,7 +1304,7 @@
 		kfree(svsk);
 	} else {
 		spin_unlock_bh(&serv->sv_lock);
-		dprintk(KERN_NOTICE "svc: server socket destroy delayed\n");
+		dprintk(KERN_NOTICE_STR "svc: server socket destroy delayed\n");
 		/* svsk->sk_server = NULL; */
 	}
 }
--- net/core/netfilter.c-orig	2002-10-24 19:16:38.000000000 -0700
+++ net/core/netfilter.c	2002-10-24 19:18:45.000000000 -0700
@@ -584,15 +584,16 @@
 		fl.fl4_src = 0;
 
 	if ((err=ip_route_output_key(&rt, &fl)) != 0) {
+#ifdef CONFIG_IP_ROUTE_FWMARK
+#define FWMARK (*pskb)->nfmark
+#else
+#define FWMARK 0UL
+#endif
 		printk("route_me_harder: ip_route_output_key(dst=%u.%u.%u.%u, src=%u.%u.%u.%u, oif=%d, tos=0x%x, fwmark=0x%lx) error %d\n",
 			NIPQUAD(iph->daddr), NIPQUAD(iph->saddr),
 			(*pskb)->sk ? (*pskb)->sk->bound_dev_if : 0,
 			RT_TOS(iph->tos)|RTO_CONN,
-#ifdef CONFIG_IP_ROUTE_FWMARK
-			(*pskb)->nfmark,
-#else
-			0UL,
-#endif
+                        FWMARK,
 			err);
 		goto out;
 	}
--- net/unix/af_unix.c-orig	2002-10-24 19:43:00.000000000 -0700
+++ net/unix/af_unix.c	2002-10-24 19:44:07.000000000 -0700
@@ -1882,7 +1882,8 @@
 static inline void unix_sysctl_unregister(void) {}
 #endif
 
-static char banner[] __initdata = KERN_INFO "NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.\n";
+static char banner[] __initdata = KERN_INFO_STR 
+	"NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.\n";
 
 static int __init af_unix_init(void)
 {
--- net/ipv4/tcp_timer.c-orig	2002-10-24 19:19:27.000000000 -0700
+++ net/ipv4/tcp_timer.c	2002-10-24 19:19:48.000000000 -0700
@@ -35,7 +35,7 @@
 static void tcp_delack_timer(unsigned long);
 static void tcp_keepalive_timer (unsigned long data);
 
-const char timer_bug_msg[] = KERN_DEBUG "tcpbug: unknown timer value\n";
+const char timer_bug_msg[] = KERN_DEBUG_STR "tcpbug: unknown timer value\n";
 
 /*
  * Using different timers for retransmit, delayed acks and probes
--- arch/i386/kernel/head.S-orig	2002-10-24 19:45:20.000000000 -0700
+++ arch/i386/kernel/head.S	2002-10-24 19:45:41.000000000 -0700
@@ -323,7 +323,7 @@
 	movl %eax,%ds
 	movl %eax,%es
 	pushl $int_msg
-	call printk
+	call _printk
 	popl %eax
 	popl %ds
 	popl %es
--- arch/i386/kernel/dmi_scan.c-orig	2002-10-24 18:55:01.000000000 -0700
+++ arch/i386/kernel/dmi_scan.c	2002-10-24 18:55:05.000000000 -0700
@@ -756,7 +756,7 @@
 			NO_MATCH, NO_MATCH, NO_MATCH
 			} },
 
-	{ print_if_true, KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.", {
+	{ print_if_true, KERN_WARNING_STR "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.", {
 			MATCH(DMI_SYS_VENDOR, "IBM"),
 			MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"),
 			NO_MATCH, NO_MATCH

Re: [RFC] CONFIG_TINY

[Daniel Phillips]

On Wednesday 23 October 2002 21:51, Rasmus Andersen wrote:
> The purpose of this mail is to get feedback in form of further
> areas where kernel size could be reduced, to learn if others
> are looking at some of these points and to see if I get some
> of the aforementioned 'never going to make it' noises.

Well, actually the main point is to get the CONFIG_TINY symbol into 
mainline, even if it doesn't do much at first.  That in itself will
be enough to inspire various artists to contribute their own
creative minimalizing hacks to the subsystems in which they have
specific expertise.

I'll bet you beer that some of the minimized subsystems eventually
supplant their more bloated brethren, as superior in every way.

-- 
Daniel