Re: [BUG] perf tools: Demangle kernel and kernel module symbols too

[Avi Kivity <avi@cloudius-systems.com>]

On 09/06/2014 09:46 PM, Jiri Olsa wrote:
> hi,
> Jan Stancek found test 1 breakage, probably caused by following patch:
>    950b8354716e perf tools: Demangle kernel and kernel module symbols too
>
> it seems to break test 1:
> ---
> [jolsa@krava perf]$ ./perf test -v 1
>   1: vmlinux symtab matches kallsyms                        :
> --- start ---
> test child forked, pid 6288
> Looking at the vmlinux_path (6 entries long)
>
> SNIP
>
> 0xffffffff8142dba0: diff name v: event_queue virtual table k: __vt_event_queue
> 0xffffffff8142dc00: diff name v: event_dequeue virtual table k: __vt_event_dequeue
> 0xffffffff8142dd90: diff name v: event_wait::isra::::part:: virtual table k: __vt_event_wait.isra.0.part.1
> ---
>
> Avi,
> could you please update the tests/vmlinux-kallsyms.c to reflect
> the demangle change?
>
>

It's not a simple matter of updating the test: the demangler interprets 
name beginning with __vt as C++ mangles names, which of course they aren't.

The only way I see to proceed is to make the demangling optional, 
default off.