Re: [RFC 07/11] eth: ixgbe: use dma_alloc_coherent_node()

["Björn Töpel" <bjorn@kernel.org>]

Jakub Kicinski <kuba@kernel.org> writes:

> Use dma_alloc_coherent_node() to place the descriptor rings on the
> node of the ring's q_vector, instead of temporarily changing the node
> of the device. NUMA_NO_NODE (ring without a q_vector) means no
> preference, same as what set_dev_node(dev, NUMA_NO_NODE) resulted in.
>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
>  drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 20 ++++++-------------
>  1 file changed, 6 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index f91856498eb2..770648f8ab89 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -7083,7 +7083,6 @@ static int ixgbe_sw_init(struct ixgbe_adapter *adapter,
>  int ixgbe_setup_tx_resources(struct ixgbe_ring *tx_ring)
>  {
>  	struct device *dev = tx_ring->dev;
> -	int orig_node = dev_to_node(dev);
>  	int ring_node = NUMA_NO_NODE;
>  	int size;
>  
> @@ -7102,12 +7101,9 @@ int ixgbe_setup_tx_resources(struct ixgbe_ring *tx_ring)
>  	tx_ring->size = tx_ring->count * sizeof(union ixgbe_adv_tx_desc);
>  	tx_ring->size = ALIGN(tx_ring->size, 4096);
>  
> -	set_dev_node(dev, ring_node);
> -	tx_ring->desc = dma_alloc_coherent(dev,
> -					   tx_ring->size,
> -					   &tx_ring->dma,
> -					   GFP_KERNEL);
> -	set_dev_node(dev, orig_node);
> +	tx_ring->desc = dma_alloc_coherent_node(dev, tx_ring->size,
> +						&tx_ring->dma, GFP_KERNEL,
> +						ring_node);
>  	if (!tx_ring->desc)
>  		tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
>  						   &tx_ring->dma, GFP_KERNEL);

Not really this series, but the fallback here is odd, no? I thought the
allocator already did cross-zone fallback?


Björn