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Subject: Re: Service core statistics MT safety
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To: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>,
 =?UTF-8?Q?Morten_Br=c3=b8rup?= <mb@smartsharesystems.com>,
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On 2022-06-27 19:39, Honnappa Nagarahalli wrote:
> <snip>
>>
>>> From: Mattias Rönnblom [mailto:mattias.ronnblom@ericsson.com]
>>> Sent: Monday, 27 June 2022 13.06
>>>
>>> Hi.
>>>
>>> Is it safe to enable stats on MT safe services?
>>>
>>> https://github.com/DPDK/dpdk/blob/main/lib/eal/common/rte_service.c#L3
>>> 6
>>> 6
>>>
>>> It seems to me this would have to be an __atomic_add for this code to
>>> produce deterministic results.
>>
>> I agree. The same goes for the 'calls' field.
> The calling function does the locking. https://github.com/DPDK/dpdk/blob/main/lib/eal/common/rte_service.c#L398
> 
> For more information you can look at: https://github.com/DPDK/dpdk/blob/main/lib/eal/include/rte_service.h#L120
> 

What about the
https://github.com/DPDK/dpdk/blob/main/lib/eal/common/rte_service.c#L404
call (for MT safe services)?

There's no lock held there.