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Date: Tue, 2 Aug 2016 22:30:00 -0500
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
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        Byungchul Park <byungchul.park@lge.com>
Subject: Re: [PATCH 05/19] x86/dumpstack: fix function graph tracing stack
 dump reliability issues
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On Tue, Aug 02, 2016 at 11:18:57PM -0400, Steven Rostedt wrote:
> On Tue, 2 Aug 2016 22:12:33 -0500
> Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> 
> 
> > Sounds good.  I was thinking I could also add a similar define to
> > indicate whether an arch passes the return address stack pointer to
> > ftrace_push_return_trace().  HAVE_FUNCTION_GRAPH_RET_ADDR_PTR?
> > 
> 
> If you are making this function global, might as well make all pass
> that pointer when you do the conversion. I don't think we need a define
> to differentiate it.

In theory, I like the idea.  But from what I can tell, it looks like a
few arches would require some assembly changes: s390, powerpc, and
sparc.  I can probably handle s390 and power, but sparc is a whole
different story...

-- 
Josh