Re: Systemtap on the ARM processor....

[William Cohen <wcohen at redhat dot com>]

On 03/29/2010 09:40 AM, Goeusse, Francois wrote:
> Hi,
> 
> Systemtap is being tested on TI OMAP platforms (ARM based) for a couple of months.
> If this can help, some resulting quick guidelines have been captured and are shared with the community at the following url: http://omappedia.org/wiki/Systemtap
> 
> Based on documentation delivered with systemtap and these perfectible guidelines, the tool is now functional and already significantly helps for the ARM platform debug and characterization.
> 
> As you will probably notice, systemtap rel 1.0 required some minor code tuning (kernel and tool) to run on our ARM based platform (OMAP/Android, OMAP/Poky).
> Furthermore, as of today, the test coverage remains incomplete as the testsuite does not seem to fully comply with cross compilation (as mentioned by Naresh as well).
> 
> Because we have not yet migrated to the latest releases of the tool, some of these code updates might no longer be required.
> However, if you believe systemtap ARM users can assist you in a way or another in the product maturation on their platforms, I guess the discussion can surely be opened.
> 
> Regards,
> 
> Francois

Hi Francois,

It is nice to see a web page describing how to use systemtap on ARM in more detail:

http://omappedia.org/wiki/Systemtap


Having separate patches is a pain. Would it be possible to work on getting those patches into the upstream SystemTap package? It looks like some of the patches will need to be reworked to ensure the don't cause systemtap to fail on non-ARM machines.  

Is the kernel/arch/arm/include/asm/ptrace.h patch needed for systemtap? I didn't see anywhere in the systemtap or its runtime code that condition_codes() is used.

The wiki page mentions a library of scripts at: http://omappedia.org/wiki/Systemtap

Are any of those general purpose that would be useful for other platforms? Any submissions to the examples directory would be appreciated. Information on how to get examples included in systemtap examples directory is at:

http://sources.redhat.com/git/gitweb.cgi?p=systemtap.git;a=blob_plain;f=testsuite/systemtap.examples/README;hb=HEAD

-Will