Re: [PATCH net-next v3 08/23] eth: bnxt: set page pool page order based on rx_page_size

[Pavel Begunkov <asml.silence@gmail.com>]

On 8/19/25 20:43, Mina Almasry wrote:
> On Mon, Aug 18, 2025 at 6:56 AM Pavel Begunkov <asml.silence@gmail.com> wrote:
>>
>> From: Jakub Kicinski <kuba@kernel.org>
>>
>> If user decides to increase the buffer size for agg ring
>> we need to ask the page pool for higher order pages.
>> There is no need to use larger pages for header frags,
>> if user increase the size of agg ring buffers switch
>> to separate header page automatically.
>>
>> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
>> [pavel: calculate adjust max_len]
>> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
>> ---
>>   drivers/net/ethernet/broadcom/bnxt/bnxt.c | 7 ++++++-
>>   1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
>> index 5307b33ea1c7..d3d9b72ef313 100644
>> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
>> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
>> @@ -3824,11 +3824,13 @@ static int bnxt_alloc_rx_page_pool(struct bnxt *bp,
>>          pp.pool_size = bp->rx_agg_ring_size / agg_size_fac;
>>          if (BNXT_RX_PAGE_MODE(bp))
>>                  pp.pool_size += bp->rx_ring_size / rx_size_fac;
>> +
>> +       pp.order = get_order(bp->rx_page_size);
>>          pp.nid = numa_node;
>>          pp.netdev = bp->dev;
>>          pp.dev = &bp->pdev->dev;
>>          pp.dma_dir = bp->rx_dir;
>> -       pp.max_len = PAGE_SIZE;
>> +       pp.max_len = PAGE_SIZE << pp.order;
> 
> nit: I assume this could be `pp.max_len = bp->rx_ring_size;` if you
> wanted, since bnxt is not actually using the full compound page in the
> case that bp->rx_ring_size is not a power of 2. Though doesn't matter
> much, either way:

Yeah, thought it's cleaner to derive it from order in case
sth about rx_page_size changes again and it was already
overlooked once, and it's pow2 anyway

-- 
Pavel Begunkov