Re: [RFC] perf probe: Fix module probe issue if no dwarf support

[Ravi Bangoria]

On Tuesday 26 April 2016 02:59 AM, Masami Hiramatsu wrote:
> On Mon, 25 Apr 2016 16:08:28 +0530
> Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxxxxxxx> wrote:
>
> > Perf is not able to register probe in kernel module when dwarf supprt
> > is not there(and so it goes for symtab). Perf passes full path of
> > module where only module name is required which is causing the problem.
> > This patch fixes this issue.
> >
> > Before applying patch:
> >
> >    $ dpkg -s libdw-dev
> >      dpkg-query: package 'libdw-dev' is not installed ...
> >
> >    $ ./perf probe -m /linux/samples/kobject/kobject-example.ko foo_show
> >      Added new event:
> >        probe:foo_show (on foo_show in /linux/samples/kobject/kobject-example.ko)
> >
> >      You can now use it in all perf tools, such as:
> >
> >    perf record -e probe:foo_show -aR sleep 1
> >
> >    $ cat /sys/kernel/debug/tracing/kprobe_events
> >      p:probe/foo_show /linux/samples/kobject/kobject-example.ko:foo_show
> >
> > After applying patch:
> >
> >    $ ./perf probe -m /linux/samples/kobject/kobject-example.ko foo_show
> >      Added new event:
> >        probe:foo_show (on foo_show in kobject_example)
> >
> >      You can now use it in all perf tools, such as:
> >
> >    perf record -e probe:foo_show -aR sleep 1
> >
> >    $ cat /sys/kernel/debug/tracing/kprobe_events
> >      p:probe/foo_show kobject_example:foo_show
> Looks good to me :)
> However, it seems that this patch depends on your previous patch
> ("perf probe: Fix offline module name missmatch issue")
> In that case, could you make these a series of patches?
>
> Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

Thanks Masami,

I've sent v2 with changes you suggested. Please review it.

Regards,
Ravi