2010-04-14 04:55:48

by Steven J. Magnani

[permalink] [raw]
Subject: [PATCH 2/2] microblaze: allow developer selection of STACKTRACE

Allow the developer to configure STACKTRACE to enable userland access to backtraces in /proc/NN/stack.

Signed-off-by: Steven J. Magnani <[email protected]>
---
diff -uprN a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
--- a/arch/microblaze/Kconfig 2010-04-09 21:52:36.000000000 -0500
+++ b/arch/microblaze/Kconfig 2010-04-12 22:16:01.000000000 -0500
@@ -136,6 +136,14 @@ config PROC_DEVICETREE
an image of the device tree that the kernel copies from Open
Firmware or other boot firmware. If unsure, say Y here.

+config PROC_BACKTRACE
+ bool "Support for kernel backtraces in /proc/NN/stack"
+ default n
+ select STACKTRACE
+ help
+ This option adds a backtrace of the kernel stack to /proc/NN/stack.
+ If unsure, say N here.
+
endmenu

menu "Advanced setup"


2010-04-14 15:25:21

by Michal Simek

[permalink] [raw]
Subject: Re: [PATCH 2/2] microblaze: allow developer selection of STACKTRACE

Steven J. Magnani wrote:
> Allow the developer to configure STACKTRACE to enable userland access to backtraces in /proc/NN/stack.
>
> Signed-off-by: Steven J. Magnani <[email protected]>
> ---
> diff -uprN a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
> --- a/arch/microblaze/Kconfig 2010-04-09 21:52:36.000000000 -0500
> +++ b/arch/microblaze/Kconfig 2010-04-12 22:16:01.000000000 -0500
> @@ -136,6 +136,14 @@ config PROC_DEVICETREE
> an image of the device tree that the kernel copies from Open
> Firmware or other boot firmware. If unsure, say Y here.
>
> +config PROC_BACKTRACE
> + bool "Support for kernel backtraces in /proc/NN/stack"
> + default n
> + select STACKTRACE
> + help
> + This option adds a backtrace of the kernel stack to /proc/NN/stack.
> + If unsure, say N here.
> +

Why did you create new Kconfig option? /proc/NN/stack is there when you
enable stacktrace support. There is not necessary to enable any new option.

Or is there any other point which I am missing?

Thanks,
Michal


> endmenu
>
> menu "Advanced setup"
>
>


--
Michal Simek, Ing. (M.Eng)
w: http://www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/
Microblaze U-BOOT custodian

2010-04-14 15:44:19

by Steven J. Magnani

[permalink] [raw]
Subject: Re: [PATCH 2/2] microblaze: allow developer selection of STACKTRACE

On Wed, 2010-04-14 at 17:25 +0200, Michal Simek wrote:
> Steven J. Magnani wrote:
> > Allow the developer to configure STACKTRACE to enable userland access to backtraces in /proc/NN/stack.
> >
> > Signed-off-by: Steven J. Magnani <[email protected]>
> > ---
> > diff -uprN a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
> > --- a/arch/microblaze/Kconfig 2010-04-09 21:52:36.000000000 -0500
> > +++ b/arch/microblaze/Kconfig 2010-04-12 22:16:01.000000000 -0500
> > @@ -136,6 +136,14 @@ config PROC_DEVICETREE
> > an image of the device tree that the kernel copies from Open
> > Firmware or other boot firmware. If unsure, say Y here.
> >
> > +config PROC_BACKTRACE
> > + bool "Support for kernel backtraces in /proc/NN/stack"
> > + default n
> > + select STACKTRACE
> > + help
> > + This option adds a backtrace of the kernel stack to /proc/NN/stack.
> > + If unsure, say N here.
> > +
>
> Why did you create new Kconfig option? /proc/NN/stack is there when you
> enable stacktrace support. There is not necessary to enable any new option.
>
> Or is there any other point which I am missing?

AFAICT STACKTRACE is an embedded option that isn't presented in the
menu. If all you want is /proc/NN/stack without the baggage of kmemleak,
tracing, etc., I didn't see a way to configure it.

This probably belongs somewhere more generic, maybe lib/Kconfig.debug?

Steve

2010-04-14 16:49:26

by Michal Simek

[permalink] [raw]
Subject: Re: [PATCH 2/2] microblaze: allow developer selection of STACKTRACE

Steven J. Magnani wrote:
> On Wed, 2010-04-14 at 17:25 +0200, Michal Simek wrote:
>> Steven J. Magnani wrote:
>>> Allow the developer to configure STACKTRACE to enable userland access to backtraces in /proc/NN/stack.
>>>
>>> Signed-off-by: Steven J. Magnani <[email protected]>
>>> ---
>>> diff -uprN a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
>>> --- a/arch/microblaze/Kconfig 2010-04-09 21:52:36.000000000 -0500
>>> +++ b/arch/microblaze/Kconfig 2010-04-12 22:16:01.000000000 -0500
>>> @@ -136,6 +136,14 @@ config PROC_DEVICETREE
>>> an image of the device tree that the kernel copies from Open
>>> Firmware or other boot firmware. If unsure, say Y here.
>>>
>>> +config PROC_BACKTRACE
>>> + bool "Support for kernel backtraces in /proc/NN/stack"
>>> + default n
>>> + select STACKTRACE
>>> + help
>>> + This option adds a backtrace of the kernel stack to /proc/NN/stack.
>>> + If unsure, say N here.
>>> +
>> Why did you create new Kconfig option? /proc/NN/stack is there when you
>> enable stacktrace support. There is not necessary to enable any new option.
>>
>> Or is there any other point which I am missing?
>
> AFAICT STACKTRACE is an embedded option that isn't presented in the
> menu. If all you want is /proc/NN/stack without the baggage of kmemleak,
> tracing, etc., I didn't see a way to configure it.

Agree that you have to enable some option to get this functionality but
the correct question is if someone need only this functionality.

>
> This probably belongs somewhere more generic, maybe lib/Kconfig.debug?

It is more generic things.
Arnd: What do you think?

Thanks,
Michal


>
> Steve
>
>


--
Michal Simek, Ing. (M.Eng)
w: http://www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/
Microblaze U-BOOT custodian

2010-04-14 16:58:06

by Arnd Bergmann

[permalink] [raw]
Subject: Re: [PATCH 2/2] microblaze: allow developer selection of STACKTRACE

On Wednesday 14 April 2010, Michal Simek wrote:
> >>> diff -uprN a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
> >>> --- a/arch/microblaze/Kconfig 2010-04-09 21:52:36.000000000 -0500
> >>> +++ b/arch/microblaze/Kconfig 2010-04-12 22:16:01.000000000 -0500
> >>> @@ -136,6 +136,14 @@ config PROC_DEVICETREE
> >>> an image of the device tree that the kernel copies from Open
> >>> Firmware or other boot firmware. If unsure, say Y here.
> >>>
> >>> +config PROC_BACKTRACE
> >>> + bool "Support for kernel backtraces in /proc/NN/stack"
> >>> + default n
> >>> + select STACKTRACE
> >>> + help
> >>> + This option adds a backtrace of the kernel stack to /proc/NN/stack.
> >>> + If unsure, say N here.
> >>> +
> >> Why did you create new Kconfig option? /proc/NN/stack is there when you
> >> enable stacktrace support. There is not necessary to enable any new option.
> >>
> >> Or is there any other point which I am missing?
> >
> > AFAICT STACKTRACE is an embedded option that isn't presented in the
> > menu. If all you want is /proc/NN/stack without the baggage of kmemleak,
> > tracing, etc., I didn't see a way to configure it.
>
> Agree that you have to enable some option to get this functionality but
> the correct question is if someone need only this functionality.
>
> >
> > This probably belongs somewhere more generic, maybe lib/Kconfig.debug?
>
> It is more generic things.
> Arnd: What do you think?

CONFIG_STACKTRACE is currently silent option that can be selected by
others. If there is value in having it enabled without any of the others,
just make it an explicit option by adding a text to 'config BACKTRACE'
in lib/Kconfig.debug.

Arnd