[PATCH22.11 v1] net/mlx5: fix age checking crash

[rongwei liu]

Thanks Thomas.

Hi Luca: I just noticed the patch title was changed somehow when merging.
Sorry for the confusion.

On 2025/10/28 22:48, Luca Boccassi wrote:
> On Tue, 28 Oct 2025 at 13:10, Thomas Monjalon <thomas at monjalon.net> wrote:
>>
>> 28/10/2025 13:13, Luca Boccassi:
>>> On Tue, 28 Oct 2025 at 08:17, Rongwei Liu <rongweil at nvidia.com> wrote:
>>>>
>>>> When aging is configured, there is a background thread
>>>> which queries all the counters in the pool.
>>>>
>>>> Meantime, per queue flow insertion/deletion/update changes
>>>> the counter pool too. It introduces a race condition between
>>>> resetting counters's in_used and age_idx fields during flow deletion
>>>> and reading them in the background thread.
>>>>
>>>> To resolve it, all key members of counter's struct
>>>> are placed in a single uint32_t and they are accessed atomically.
>>>>
>>>> To avoid the occasional timestamp equalization with age_idx,
>>>> query_gen_when_free is moved out of the union. The total memory
>>>> size is kept the same.
>>>>
>>>> Fixes: 04a4de756e14 ("net/mlx5: support flow age action with HWS")
>>>> Cc: michaelba at nvidia.com
>>>> Cc: stable at dpdk.org
>>>> Signed-off-by: Rongwei Liu <rongweil at nvidia.com>
>>>
>>> Hi,
>>>
>>> I cannot seem to find a reference to this patch on the main branch?
>>> Was it merged with a different commit?
>>
>> It seems Rongwei didn't reuse the title updated while merging in main:
>>
>> https://git.dpdk.org/dpdk/commit/?id=820ca7361bb
>>
>> Note the new title is more precise, please use it:
>>         net/mlx5: fix flow aging race condition
> 
> Sounds good, thanks