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SubjectRe: [PATCH 01/17] perf util: Save pid-cmdline mapping into tracing header
Hi Arnaldo,

2013-07-30 오후 10:28, Arnaldo Carvalho de Melo 쓴 글:
> Em Tue, Jul 30, 2013 at 06:18:58PM +0900, Namhyung Kim escreveu:
>> From: Namhyung Kim <namhyung.kim@lge.com>
>>
>> Current trace info data lacks the saved cmdline mapping which is
>> needed for pevent to find out the comm of a task. Add this and bump
>> up the version number so that perf can determine its presence when
>> reading.
>
> Can't we get this from the PERF_RECORD_COMM synthesized at the beginning
> of the session + the kernel generated ones for new threads?
>
> We would just call machine__find_thread() and use thread->comm, etc, no?

Yes, I think it's doable. However it needs an additional perf event
only to generate the COMM events. So I decided not to do it and reused
saved cmdline info from ftrace. But IIUC it also has a problem of
possible information loss due to the size of table.

Thanks,
Namhyung

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