Re: [PerfSuite-users] On hacking perfsuite

[<jj...@nu...>]

Rick,

Thanks for your suggestion!

Regards,
Jie



>From: Rick Kufrin <rk...@il...>
>Reply-To: 
>To: jj...@nu...
>Subject: Re: [PerfSuite-users] On hacking perfsuite
>Date:Fri, 08 Jan 2010 14:53:40 -0600
>
>Jie Jiang wrote:
> > Hi Rick,
> >
> > I'd like to hack Perfsuite to record some special information about the
> > target application along with the performance data collected by
> > perfsuite (such as profile, hardware PMU data, etc.)
> >
> > We have hacked OS kernel to provide a new syscall to collect such
> > desired information. And I wish this syscall be called in libperfsuite,
> > collect information and write the results in perfsuite's output files,
> > together with perfsuite's performance data.
> >
> > Where should I start?
> >
> > Regards,
> > Jie Jiang
> >
> >
> >
> >
> >   
> 
> Jie,
> 
> That sounds interesting and shouldn't be too difficult to do.  Here is 
> the way to go about it:
> 
> - additions to the data collected (your new syscall) belong in the 
> library libpshwpc, not libperfsuite.
> 
> - C structures that hold the data are #define'd in the file hwpc.h.  
> Assuming that the data you want to add is on a per-thread basis, it 
> should be added to the structure call ps_hwpc_values_t
> 
> - the code that actually does the collection is contained in the file 
> hwpc.c.  This is basically the top-level entry point to the collection 
> library.  I am guessing you will want to call your new system call once, 
> at the end of execution.  If that is the case, then the appropriate 
> function to do that in is ps_hwpc_stop(), where you would execute your 
> syscall and store the results in the existing structure "values" (the 
> type is as above)
> 
> - finally, you will want the new item written out to the XML output 
> document.  To do that, you will need to add additional code to the 
> output routine in hwpc-xml.c.  That file should be pretty 
> straightforward to understand.  You will probably want to define a new 
> XML element tag (a name of your choice) for your data. It's up to you 
> where you want it placed within the document.  This will now become an 
> invalid document (from the XML perspective), but that shouldn't matter 
> as validation is not done in post-processing.
> 
> Next, if you want the psprocess utility to be able to parse out and 
> display the new data you have added, you will need to modify its 
> implementation as well.  There are now two versions of psprocess (Tcl 
> and Java), and the default is Tcl.  The appropriate file to modify to 
> add the new data is called hwpcreport.tcl.  I do not know if you are 
> familiar with Tcl, but perhaps basing changes on the existing code in 
> there is the way to go.  If you intend to work with the Java version of 
> psprocess, let us know and we can try to assist you with that.
> 
> Hope that helps,
> 
> Rick
> 
>