[PATCH v4 3/3] mempool: use cache for frequently updated stats

[Andrew Rybchenko]

On 11/6/22 14:50, Morten Brørup wrote:
>> From: Andrew Rybchenko [mailto:andrew.rybchenko at oktetlabs.ru]
>> Sent: Sunday, 6 November 2022 12.41
>>
>> On 11/4/22 15:03, Morten Brørup wrote:
> 
> [...]
> 
>>> +/**
>>> + * @internal When stats is enabled, store some statistics.
>>> + *
>>> + * @param cache
>>> + *   Pointer to the memory pool cache.
>>> + * @param name
>>> + *   Name of the statistics field to increment in the memory pool
>> cache.
>>> + * @param n
>>> + *   Number to add to the statistics.
>>> + */
>>> +#ifdef RTE_LIBRTE_MEMPOOL_STATS
>>> +#define RTE_MEMPOOL_CACHE_STAT_ADD(cache, name, n) (cache)-
>>> stats.name += n
>>
>> I'd enclose it in parenthesis.
> 
> Me too! I had it surrounded by "do {...} while (0)" in v3, but checkpatch complained about it [1], so I changed it to the above. Which checkpatch also complains about. :-(

I mean
#define RTE_MEMPOOL_CACHE_STAT_ADD(cache, name, n) \
  ((cache)->stats.name += (n))

> 
> [1]: http://mails.dpdk.org/archives/test-report/2022-November/321316.html

Yes, I've seen it.

> 
> Feel free to modify this macro at your preference when merging!
> 
>>
>>> +#else
>>> +#define RTE_MEMPOOL_CACHE_STAT_ADD(cache, name, n) do {} while (0)
>>> +#endif
>>> +
>