[Questions] How to run 'perf top' on ARM to profile kernel functions with modules loaded

[Jamie Iles]

On Thu, Nov 11, 2010 at 03:52:07PM +0800, Ming Lei wrote:
> 2010/11/11 Ming Lei <tom.leiming at gmail.com>:
> > Hi,
> >
> > 'perf top' can't display any functions when modules are loaded on ARM.
> 
> Sorry, should be can't display any kernel functions when modules are loaded
> on ARM.
I've noticed this myself and I spent a bit of time looking into it last week 
but didn't get too far. I did wonder if it was something to do with the map 
fixups after loading the modules. If you look at the raw events after a perf 
record with 'perf report -D' then the last module has a size that takes it to 
0xFFFFFFFF which overlaps with the rest of the kernel symbols.

On x86 it looks like the modules are loaded after the kernel image in VM 
unlike ARM.

Jamie