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Date: Wed, 12 Jul 2017 17:40:45 -0500
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Andres Freund <andres@anarazel.de>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
        live-patching@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@kernel.org>, Jiri Slaby <jslaby@suse.cz>,
        Ingo Molnar <mingo@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>, Mike Galbraith <efault@gmx.de>
Subject: Re: [PATCH v3 00/10] x86: ORC unwinder (previously undwarf)
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On Wed, Jul 12, 2017 at 03:36:05PM -0700, Andres Freund wrote:
> Hi,
> 
> On 2017-07-12 17:32:25 -0500, Josh Poimboeuf wrote:
> > If you want perf to be able to use ORC instead of DWARF for user space
> > binaries, that's not currently possible, though I don't see any
> > technical blockers for doing so.  Perf would need to be taught to read
> > ORC data.
> 
> Right, that's what I was hoping for.
> 
> 
> > And I think it should be possible to convert DWARF to ORC, assuming the
> > DWARF data is trusted.  We could probably add an objtool subcommand for
> > that.
> 
> That'd be pretty helpful.

Can I ask why?  Is DWARF too slow, or is it something else?

-- 
Josh