Re: [BUG] perf: No samples found when using kcore + coresight

Yang Shi
2023-03-28T16:17:35Z

On 3/28/23 1:59 AM, James Clark wrote:
>
> On 28/03/2023 01:53, Yang Shi wrote:
>> Hi Leo,
>>
>> Just follow up on this one. Any update?
>>
> Hi Yang,
>
> Sorry no update on this yet from me. I was just finishing off
> "coresight: Fix CTI module refcount leak by making it a helper device"
> which I hope to post in the next day or two and then I will start on this.

Hi James,

Thank you for the update.

>
> James
>
>> Thanks,
>> Yang
>>
>> On Mon, Mar 13, 2023 at 5:36 PM Leo Yan <leo.yan@linaro.org> wrote:
>>> On Mon, Mar 13, 2023 at 11:15:44AM -0700, Yang Shi wrote:
>>>
>>> [...]
>>>
>>>>> Just a quick summary, here we have two issues:
>>>>>
>>>>> - With command:
>>>>> perf record -e cs_etm/@tmc_etf63/k --kcore --per-thread \
>>>>> -- taskset --cpu-list 1 uname",
>>>>>
>>>>> perf doesn't enable "text poke" attribution.
>>>> No, it enables "text poke" and perf fails to decode coresight trace
>>>> data too. It doesn't matter whether "--kcore" is after or before "-e
>>>> cs/etm/@tmc_etf63/k".
>>> Understand now. Thanks for correction, if so we can ignore this one.
>>>
>>> Leo