Re: [PATCH for-next 3/3] RDMA/erdma: Remove unnecessary __GFP_ZERO flag

Leon Romanovsky
2024-03-12T10:53:09Z

On Mon, Mar 11, 2024 at 07:38:21PM +0800, Boshi Yu wrote:
> From: Boshi Yu <boshiyu@linux.alibaba.com>
>
> The dma_alloc_coherent() interface automatically zero the memory returned.

Can you please point to the DMA code which does that?

> Thus, we do not need to specify the __GFP_ZERO flag explicitly when we call
> dma_alloc_coherent().
>
> Reviewed-by: Cheng Xu <chengyou@linux.alibaba.com>
> Signed-off-by: Boshi Yu <boshiyu@linux.alibaba.com>
> ---
> drivers/infiniband/hw/erdma/erdma_cmdq.c | 6 ++----
> drivers/infiniband/hw/erdma/erdma_eq.c | 6 ++----
> 2 files changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/infiniband/hw/erdma/erdma_cmdq.c b/drivers/infiniband/hw/erdma/erdma_cmdq.c
> index 0ac2683cfccf..43ff40b5a09d 100644
> --- a/drivers/infiniband/hw/erdma/erdma_cmdq.c
> +++ b/drivers/infiniband/hw/erdma/erdma_cmdq.c
> @@ -127,8 +127,7 @@ static int erdma_cmdq_cq_init(struct erdma_dev *dev)
>
> cq->depth = cmdq->sq.depth;
> cq->qbuf = dma_alloc_coherent(&dev->pdev->dev, cq->depth << CQE_SHIFT,
> - &cq->qbuf_dma_addr,
> - GFP_KERNEL | __GFP_ZERO);
> + &cq->qbuf_dma_addr, GFP_KERNEL);
> if (!cq->qbuf)
> return -ENOMEM;
>
> @@ -162,8 +161,7 @@ static int erdma_cmdq_eq_init(struct erdma_dev *dev)
>
> eq->depth = cmdq->max_outstandings;
> eq->qbuf = dma_alloc_coherent(&dev->pdev->dev, eq->depth << EQE_SHIFT,
> - &eq->qbuf_dma_addr,
> - GFP_KERNEL | __GFP_ZERO);
> + &eq->qbuf_dma_addr, GFP_KERNEL);
> if (!eq->qbuf)
> return -ENOMEM;
>
> diff --git a/drivers/infiniband/hw/erdma/erdma_eq.c b/drivers/infiniband/hw/erdma/erdma_eq.c
> index 0a4746e6d05c..84ccdd8144c9 100644
> --- a/drivers/infiniband/hw/erdma/erdma_eq.c
> +++ b/drivers/infiniband/hw/erdma/erdma_eq.c
> @@ -87,8 +87,7 @@ int erdma_aeq_init(struct erdma_dev *dev)
> eq->depth = ERDMA_DEFAULT_EQ_DEPTH;
>
> eq->qbuf = dma_alloc_coherent(&dev->pdev->dev, eq->depth << EQE_SHIFT,
> - &eq->qbuf_dma_addr,
> - GFP_KERNEL | __GFP_ZERO);
> + &eq->qbuf_dma_addr, GFP_KERNEL);
> if (!eq->qbuf)
> return -ENOMEM;
>
> @@ -237,8 +236,7 @@ static int erdma_ceq_init_one(struct erdma_dev *dev, u16 ceqn)
>
> eq->depth = ERDMA_DEFAULT_EQ_DEPTH;
> eq->qbuf = dma_alloc_coherent(&dev->pdev->dev, eq->depth << EQE_SHIFT,
> - &eq->qbuf_dma_addr,
> - GFP_KERNEL | __GFP_ZERO);
> + &eq->qbuf_dma_addr, GFP_KERNEL);
> if (!eq->qbuf)
> return -ENOMEM;
>
> --
> 2.39.3
>
>