[dpdk-dev] [PATCH 21.02 v2] mem: don't warn about base addr if not requested

[Burakov, Anatoly]

On 09-Nov-20 3:47 PM, Anatoly Burakov wrote:
> Any EAL memory allocation often goes through eal_get_virtual_area()
> function, which will print a warning whenever the resulting allocation
> didn't match the specified address requirements. This is useful for
> when we have requested a specific base virtual address, to let the user
> know that the mapping has deviated from that address.
> 
> However, on Linux, we also have a default base address that's there to
> ensure better chances of successful secondary process initialization,
> as well as higher likelihood of the virtual areas to fit inside the
> IOMMU address width. Because of this default base address, there are
> warnings printed even when no base address was explicitly requested,
> which can be confusing to the user.
> 
> Emit this warning with debug level unless base address was explicitly
> requested by the user.
> 
> Cc: Damjan Marion <damarion at cisco.com>
> 
> Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
> ---
> 
> Notes:
>      v2:
>      - Fix the condition to not update the address incorrectly
>      - Instead of removing the warning, let it have debug level unless base address
>        was explicitly specified by the user
>      
>      I'm not entirely sure the trade off between user confusion and helpful debug
>      information is worth it, but in my experience, i've stopped getting any emails
>      about secondary processes a long time ago and this isn't a widely used feature,
>      so i believe this is worth it.

For some reason i didn't get David's comment in my inbox, so i'll copy 
it here:

 > EAL options like --in-memory or --no-shconf makes MP unusable.
 > If we add a rte_mp_disable() for them, we could check here for MP
 > status here and display nothing at all.
 > WDYT?

That sounds like a nice idea, but this patch addresses a different issue.

-- 
Thanks,
Anatoly