Re: [PATCH 2/2] perf annotate: add powerpc support

[Naveen N. Rao]

On 2016/06/10 10:36AM, Arnaldo Carvalho de Melo wrote:
> Em Fri, Jun 10, 2016 at 06:32:51PM +0530, Naveen N. Rao escreveu:
> > Convert ins__find() to a __weak function for generic functionality,
> > while adding a powerpc-specific variant. We look at the function name
> > for branch instructions and classify the instructions to one among a
> > branch, a function call (branch with LR update) or a function return
> > (branch to LR).
> 
> How would this allow one to get a perf.data collected on a powerpc
> system, transfer it to a x86-64 (or aarch64, to mention another
> workstation wannabe chip) system and then try annotating it?
> 
> There was a previous discussion about this, and it involved having all
> yout ppc tables available as well as other arches tables, and then
> choosing which one to use based on:
> 
> 	normalize_arch(thread->mg->machine->env->arch)
> 
> just like was done for support cross unwinding, see recent patch kit by
> He Kuang, CCed.

Nice. This would be good to have. I will look at adding powerpc support 
for cross-architecture unwind.

However, for cross-architecture annotation, I think there will be a lot 
more dependencies since perf currently uses objdump to obtain the 
disassembly. In addition, the actual binaries will also be needed.


- Naveen