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Date: Mon, 16 Apr 2012 17:57:37 +0530
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@elte.hu>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
        Jim Keniston <jkenisto@linux.vnet.ibm.com>,
        LKML <linux-kernel@vger.kernel.org>, Linux-mm <linux-mm@kvack.org>,
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        Christoph Hellwig <hch@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>, Anton Arapov <anton@redhat.com>
Subject: Re: [PATCH] perf/probe: Provide perf interface for uprobes
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Reply-To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
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> 
> > > Another case 
> > > perf probe do_fork clone_flags now looks for variable clone_flags in
> > > kernel function do_fork.
> 
> > > But if we allow to trace perf probe zsh zfree; then 
> > > 'perf probe do_fork clone_flags' should it check for do_fork executable
> > > or not? If it does check and finds one, and searches for clone_flags
> > > function and doesnt find, then should it continue with searching the
> > > kernel?
> 
> > Agree. I'd like to suggest you to start with only full path support,
> > and see, how we can handle abbreviations :)
> 
> Agreed, I was just making usability suggestions.
> 
> Those can be implemented later, if we agree they ease the tool use.
> 

I have just made a prototype for guessing the target when -m and -x
options arent passed. That still uses the absolute path for now.

I was trying to see if we can identify the module by the short name by
using kernel_get_module_path(). However kernel_get_module_path() needs
init_vmlinux() to be called before. Since init_vmlinux() cant be called
more than once and init_vmlinux gets called later, I thought calling it
here wasnt good option. Wanted to see if we could open /proc/modules
and then match the module name.  But again, I wasnt sure how to handle
offline modules.  

-- 
Thanks and Regards
Srikar