Re: [PATCH v7 10/14] perf tools: Check the target platform before assigning unwind methods

[Hekuang]

å 2016/6/1 16:40, Jiri Olsa åé:
> On Tue, May 31, 2016 at 11:19:08AM +0000, He Kuang wrote:
>
> SNIP
>
> > -int unwind__prepare_access(struct thread *thread)
> > +int unwind__prepare_access(struct thread *thread, struct map *map)
> >   {
> > -	unwind__register_ops(thread, local_unwind_libunwind_ops);
> > +	const char *arch;
> > +	enum dso_type dso_type;
> > +	struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
> >   
> > -	return thread->unwind_libunwind_ops->prepare_access(thread);
> > +	if (!thread->mg->machine->env)
> > +		return 0;
> > +
> > +	dso_type = dso__type(map->dso, thread->mg->machine);
> > +	if (dso_type == DSO__TYPE_UNKNOWN)
> > +		return 0;
> > +
> > +	if (thread->addr_space)
> > +		pr_debug("unwind: thread map already set, 64bit is %d, dso=%s\n",
> > +			 dso_type == DSO__TYPE_64BIT, map->dso->name);
> should we leave once the address space is set? resseting it over
> again seems like memory leak unless I'm missing something...
>
> also this check should be probably the first thing we do in here

Sure, I must miss the return statement here.
> thanks,
> jirka
>
> > +
> > +	arch = normalize_arch(thread->mg->machine->env->arch);
> > +	pr_debug("unwind: target platform=%s\n", arch);
> > +
> > +	unwind__register_ops(thread, ops);
> > +
> > +	if (thread->unwind_libunwind_ops)
> > +		return thread->unwind_libunwind_ops->prepare_access(thread);
> > +	else
> > +		return 0;
> >   }
> SNIP