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Date: Fri, 25 Oct 2013 18:29:21 +0530
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Pekka Enberg <penberg@kernel.org>
Cc: Hemant Kumar <hkshaw@linux.vnet.ibm.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Oleg Nesterov <oleg@redhat.com>,
        hegdevasant@linux.vnet.ibm.com, Ingo Molnar <mingo@redhat.com>,
        anton@redhat.com, systemtap@sourceware.org,
        Namhyung Kim <namhyung@kernel.org>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        aravinda@linux.vnet.ibm.com
Subject: Re: [PATCH v4 2/3] Support for perf to probe into SDT markers:
Message-ID: <20131025125921.GA29424@linux.vnet.ibm.com>
Reply-To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
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Hi Pekka,

> >
> > You can now use it in all perf tools, such as:
> >
> >     perf record -e libc:my_event -aR sleep 1
> 
> Is there a technical reason why 'perf list' could not show all the
> available SDT markers on a system and that the 'market to event'
> mapping cannot happen automatically?
> 

Technically feasible. But then we would have to parse each of the
libraries and executables to list them. Right? I am not sure if such a
delay is acceptable.

Also if a binary exists in a path thats is not covered in the default
search, an user might believe that his binary may not have markers.
I know the above reason is more of a user folly than a tooling issue.

> So instead of doing all the command line magic above I'd do:
> 
>   perf list
> 
>   libc:setjmp [SDT marker]
> 
> and I could just do
> 
>   perf record -e libc:setjmp -AR sleep 1
> 
> ?

-- 
Thanks and Regards
Srikar Dronamraju