Re: [RFC] microblaze: Support FRAME_POINTER for better backtrace

From: Steven J. Magnani
Date: Mon Mar 01 2010 - 16:26:15 EST

Paul -

On Mon, 2010-03-01 at 10:43 +0900, Paul Mundt wrote:
> This doesn't look that bad compared to what some of the other
> architectures have to deal with. If the frame pointer is always setup
> using these addik/swi pairs then you can trivially scan an arbitrary
> number of instructions attempting to match before giving up. We do
> similar things for sh64 where we also have to figure out how stack frames
> were created in order to roll them back.
> In any event, take a look at arch/sh/kernel/cpu/sh5/unwind.c, you should
> be able to use a similar scheme without the need for undue complexity.

Thanks for the tip. This looks manageable. I had thought to search for
instructions that create frames but didn't think working backwards from
return addresses was a good idea. Using kallsyms to get the "top" of
each function is a nice way around that.

Steven J. Magnani "I claim this network for MARS! Earthling, return my space modulator!"

#include <standard.disclaimer>

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