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Subject: Re: [PATCH 3/5][RFC] ftrace: Return pt_regs to function trace
 callback (x86_64 only so
From: Steven Rostedt <rostedt@goodmis.org>
To: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Jason Baron <jbaron@redhat.com>, yrl.pp-manager.tt@hitachi.com
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On Fri, 2011-08-12 at 09:55 +0900, Masami Hiramatsu wrote:

> Please note, kprobes is the function which basically provides a
> breakpoint handler in the kernel. Users expect that. So all registers
> should be provided as breakpoint interrupt does. That's what I said
> "transparently".

Well, I think I'm on the right track then. Because I'm working to get
the function graph tracer to use this functionality as well.

I believe that I can make this work "transparently" too.

I'm now working on having ftrace use the breakpoint/update method as
well as the stop_machine() method. If an arch has an alternative to
stop_machine, then it can use that method instead.

-- Steve