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SubjectRe: [RFC] perf probe: Fix module probe issue if no dwarf support
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On Tuesday 26 April 2016 02:59 AM, Masami Hiramatsu wrote:
> On Mon, 25 Apr 2016 16:08:28 +0530
> Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> 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@kernel.org>

Thanks Masami,

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

Regards,
Ravi

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