[PATCH] doc: announce behavior change for device NUMA node field

[Bruce Richardson]

On Wed, Jul 13, 2022 at 05:50:43PM +0200, Olivier Matz wrote:
> The dev->device.numa_node field is set by the bus driver for each device
> it manages to indicate on which NUMA node this device lies.
> 
> When this information is unknown, the assigned value is not consistent
> across the bus drivers. In v22.11, the value will be set to -1 in
> this case.
> 
> Link: https://patches.dpdk.org/project/dpdk/patch/20211026090610.10823-1-houssem.bouhlel@6wind.com/
> 
> Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
> ---
>  doc/guides/rel_notes/deprecation.rst | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
> index 4e5b23c53d..5f269bf527 100644
> --- a/doc/guides/rel_notes/deprecation.rst
> +++ b/doc/guides/rel_notes/deprecation.rst
> @@ -125,3 +125,9 @@ Deprecation Notices
>    applications should be updated to use the ``dmadev`` library instead,
>    with the underlying HW-functionality being provided by the ``ioat`` or
>    ``idxd`` dma drivers
> +
> +* bus: The ``dev->device.numa_node`` field is set by the bus driver for
> +  each device it manages to indicate on which NUMA node this device
> +  lies. When this information is unknown, the assigned value is not
> +  consistent across the bus drivers. In v22.11, the value will be set
> +  to -1 in this case.

Acked-by: Bruce Richardson <bruce.richardson at intel.com>

Couple of minor rewording suggestions:
* "the bus driver" seems wrong in the first line as we haven't referred to
  one in particular. How about "...set by each bus driver for every device..."

* "the assigned value is not consistent across the bus drivers" - this
  reads a little strange to me and I find it unclear. Not sure how to
  reword it, maybe something like: "each bus driver selects its own value to
  set. To resolve this inconsistency, in v22.11, the device numa_node value
  will be set to -1 by all bus drivers when the actual NUMA information is
  unavailable."


> -- 
> 2.30.2
>