[PATCH] x86: make mtrr code could use debugpat

[PATCH] x86: make mtrr code could use debugpat

[Yinghai Lu]

Impact: cleanup

only print out get_mtrr when debugpat

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 arch/x86/kernel/cpu/mtrr/generic.c |    9 ++++++---
 arch/x86/kernel/cpu/mtrr/mtrr.h    |    4 ++++
 arch/x86/mm/pat.c                  |    6 +++---
 3 files changed, 13 insertions(+), 6 deletions(-)

Index: linux-2.6/arch/x86/kernel/cpu/mtrr/generic.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/cpu/mtrr/generic.c
+++ linux-2.6/arch/x86/kernel/cpu/mtrr/generic.c
@@ -462,9 +462,12 @@ static void generic_get_mtrr(unsigned in
 	*base = base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT;
 	*type = base_lo & 0xff;
 
-	printk(KERN_DEBUG "  get_mtrr: cpu%d reg%02d base=%010lx size=%010lx %s\n",
-			cpu, reg, *base, *size,
-			mtrr_attrib_to_str(*type & 0xff));
+#ifdef CONFIG_X86_PAT
+	if (debugpat)
+		printk(KERN_DEBUG "  get_mtrr: cpu%d reg%02d base=%010lx size=%010lx %s\n",
+				cpu, reg, *base, *size,
+				mtrr_attrib_to_str(*type & 0xff));
+#endif
 out_put_cpu:
 	put_cpu();
 }
Index: linux-2.6/arch/x86/kernel/cpu/mtrr/mtrr.h
===================================================================
--- linux-2.6.orig/arch/x86/kernel/cpu/mtrr/mtrr.h
+++ linux-2.6/arch/x86/kernel/cpu/mtrr/mtrr.h
@@ -92,3 +92,7 @@ int centaur_init_mtrr(void);
 
 extern int changed_by_mtrr_cleanup;
 extern int mtrr_cleanup(unsigned address_bits);
+
+#if CONFIG_X86_PAT
+extern int debugpat;
+#endif
Index: linux-2.6/arch/x86/mm/pat.c
===================================================================
--- linux-2.6.orig/arch/x86/mm/pat.c
+++ linux-2.6/arch/x86/mm/pat.c
@@ -51,17 +51,17 @@ static inline void pat_disable(const cha
 #endif
 
 
-static int debug_enable;
+int debugpat;
 
 static int __init pat_debug_setup(char *str)
 {
-	debug_enable = 1;
+	debugpat = 1;
 	return 0;
 }
 __setup("debugpat", pat_debug_setup);
 
 #define dprintk(fmt, arg...) \
-	do { if (debug_enable) printk(KERN_INFO fmt, ##arg); } while (0)
+	do { if (debugpat) printk(KERN_INFO fmt, ##arg); } while (0)
 
 
 static u64 __read_mostly boot_pat_state;

Re: [PATCH] x86: make mtrr code could use debugpat

[Linus Torvalds]

On Fri, 3 Apr 2009, Yinghai Lu wrote:
> 
> only print out get_mtrr when debugpat

Is that get_mtrr message really so interesting that it needs to be printed 
out at all? Even with debugpat?

			Linus

Re: [PATCH] x86: make mtrr code could use debugpat

[Yinghai Lu]

Linus Torvalds wrote:
> 
> On Fri, 3 Apr 2009, Yinghai Lu wrote:
>> only print out get_mtrr when debugpat
> 
> Is that get_mtrr message really so interesting that it needs to be printed 
> out at all? Even with debugpat?
> 

it seems some new X server try to touch MTRR at the first, and then try to use pci_mmap_page_range().

YH

Re: [PATCH] x86: make mtrr code could use debugpat

[Yinghai Lu]

Linus Torvalds wrote:
> 
> On Fri, 3 Apr 2009, Yinghai Lu wrote:
>> only print out get_mtrr when debugpat
> 
> Is that get_mtrr message really so interesting that it needs to be printed 
> out at all? Even with debugpat?

or you pick the one in tip/master that remove those line.

YH

Re: [PATCH] x86: make mtrr code could use debugpat

[Yinghai Lu]

Yinghai Lu wrote:
> Linus Torvalds wrote:
>> On Fri, 3 Apr 2009, Yinghai Lu wrote:
>>> only print out get_mtrr when debugpat
>> Is that get_mtrr message really so interesting that it needs to be printed 
>> out at all? Even with debugpat?
> 
> or you pick the one in tip/master that remove those line.
> 

should be in tip/x86/urgent

YH

Re: [PATCH] x86: make mtrr code could use debugpat

[Ingo Molnar]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Fri, 3 Apr 2009, Yinghai Lu wrote:
> > 
> > only print out get_mtrr when debugpat
> 
> Is that get_mtrr message really so interesting that it needs to be 
> printed out at all? Even with debugpat?

With debugpat it's probably interesting - i think only a very small 
fraction of users will enable it, and if they do we really want to 
track all MTRR state.

Since old MTRR state gets destroyed by new settings we better have a 
clear idea how the BIOS set it, that might give us clues about 
quirks, etc.

Based on MTRR bugreport patterns i was the one who asked Yinghai 
during the development cycle to add more debugging there - so i'm to 
blame for those printouts. We had several cases where it would have 
been useful had we known the precise history of MTRR settings.

I was under the impression that KERN_DEBUG would only show up on the 
console if 'debug' is passed in on the boot command line - but your 
bootlog didnt have 'debug' in it and i guess having it so frequently 
in the dmesg is confusing as well. It might even be there for every 
Xorg startup.

Anyway ... the x86/urgent pull request i sent removes the printk 
altogether.

	Ingo

Re: [PATCH] x86: make mtrr code could use debugpat

[Jaswinder Singh Rajput]

On Sat, 2009-04-04 at 03:18 +0200, Ingo Molnar wrote:
> * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> 
> > On Fri, 3 Apr 2009, Yinghai Lu wrote:
> > > 
> > > only print out get_mtrr when debugpat
> > 
> > Is that get_mtrr message really so interesting that it needs to be 
> > printed out at all? Even with debugpat?
> 
> With debugpat it's probably interesting - i think only a very small 
> fraction of users will enable it, and if they do we really want to 
> track all MTRR state.
> 
> Since old MTRR state gets destroyed by new settings we better have a 
> clear idea how the BIOS set it, that might give us clues about 
> quirks, etc.
> 
> Based on MTRR bugreport patterns i was the one who asked Yinghai 
> during the development cycle to add more debugging there - so i'm to 
> blame for those printouts. We had several cases where it would have 
> been useful had we known the precise history of MTRR settings.
> 
> I was under the impression that KERN_DEBUG would only show up on the 
> console if 'debug' is passed in on the boot command line - but your 
> bootlog didnt have 'debug' in it and i guess having it so frequently 
> in the dmesg is confusing as well. It might even be there for every 
> Xorg startup.
> 
> Anyway ... the x86/urgent pull request i sent removes the printk 
> altogether.
> 

Thanks for removing those annoying lines.

--
JSR

Re: [PATCH] x86: make mtrr code could use debugpat

[Jaswinder Singh Rajput]

On Sat, 2009-04-04 at 03:18 +0200, Ingo Molnar wrote:
> * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> 
> > On Fri, 3 Apr 2009, Yinghai Lu wrote:
> > > 
> > > only print out get_mtrr when debugpat
> > 
> > Is that get_mtrr message really so interesting that it needs to be 
> > printed out at all? Even with debugpat?
> 
> With debugpat it's probably interesting - i think only a very small 
> fraction of users will enable it, and if they do we really want to 
> track all MTRR state.
> 
> Since old MTRR state gets destroyed by new settings we better have a 
> clear idea how the BIOS set it, that might give us clues about 
> quirks, etc.
> 
> Based on MTRR bugreport patterns i was the one who asked Yinghai 
> during the development cycle to add more debugging there - so i'm to 
> blame for those printouts. We had several cases where it would have 
> been useful had we known the precise history of MTRR settings.
> 
> I was under the impression that KERN_DEBUG would only show up on the 
> console if 'debug' is passed in on the boot command line - but your 
> bootlog didnt have 'debug' in it and i guess having it so frequently 
> in the dmesg is confusing as well. It might even be there for every 
> Xorg startup.
> 

If you still want to debug it, use some special parameters at command
line to avoid annoyance to others.

These debug messages really screwed up my life from last month.

--
JSR

Re: [PATCH] x86: make mtrr code could use debugpat

[Jaswinder Singh Rajput]

On Sat, 2009-04-04 at 12:22 +0530, Jaswinder Singh Rajput wrote:
> On Sat, 2009-04-04 at 03:18 +0200, Ingo Molnar wrote:
> > * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> > 
> > > On Fri, 3 Apr 2009, Yinghai Lu wrote:
> > > > 
> > > > only print out get_mtrr when debugpat
> > > 
> > > Is that get_mtrr message really so interesting that it needs to be 
> > > printed out at all? Even with debugpat?
> > 
> > With debugpat it's probably interesting - i think only a very small 
> > fraction of users will enable it, and if they do we really want to 
> > track all MTRR state.
> > 
> > Since old MTRR state gets destroyed by new settings we better have a 
> > clear idea how the BIOS set it, that might give us clues about 
> > quirks, etc.
> > 
> > Based on MTRR bugreport patterns i was the one who asked Yinghai 
> > during the development cycle to add more debugging there - so i'm to 
> > blame for those printouts. We had several cases where it would have 
> > been useful had we known the precise history of MTRR settings.
> > 
> > I was under the impression that KERN_DEBUG would only show up on the 
> > console if 'debug' is passed in on the boot command line - but your 
> > bootlog didnt have 'debug' in it and i guess having it so frequently 
> > in the dmesg is confusing as well. It might even be there for every 
> > Xorg startup.
> > 
> 
> If you still want to debug it, use some special parameters at command
> line to avoid annoyance to others.
> 
> These debug messages really screwed up my life from last month.
> 

If you surprise how these debug messages screwed up my life, so here is
some clues:

1. I pointed to remove or suppress these messages and Ingo, Andrew and
then later on Thomas become upset with me.

2. And because of their upset, I need to delete more than 100 of my
patches and delete many development trees in last few weeks.

--
JSR