Re: [PATCH net-next 5/9] page_pool: don't use driver-set flags field directly

From: Yunsheng Lin
Date: Wed Aug 02 2023 - 07:36:28 EST


On 2023/8/1 21:36, Alexander Lobakin wrote:

>>
>> It just seems odd to me that dma_map and page_frag is duplicated as we
>> seems to have the same info in the page_pool->p.flags.
>
> It's just because we copy the whole &page_pool_params passed by the
> driver. It doesn't look good to me to define a new structure and copy
> the values field-by-field just to avoid duplicating 3 bits :s
>
>>
>> What about:
>> In [PATCH net-next 4/9] page_pool: shrink &page_pool_params a tiny bit,
>> 'flags' is bit-field'ed with 'dma_dir', what about changing 'dma_dir'
>> to be bit-field'ed with 'dma_sync_act', so that page_pool->p.flags stays
>> the same as before, and 'dma_map' & 'page_frag' do not seems be really
>> needed as we have the same info in page_pool->p.flags?
>
> Not sure I follow :z ::dma_dir is also passed by the driver, so we can't
> drop it from the params struct.

My bad, I missed that dma_dir is in the params struct.