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Message-ID: <1666611221.6163745-2-xuanzhuo@linux.alibaba.com>
Subject: Re: [PATCH 2/2] virtio_ring: use helper function is_power_of_2()
Date:   Mon, 24 Oct 2022 19:33:41 +0800
From:   Xuan Zhuo <xuanzhuo@linux.alibaba.com>
To:     shaoqin.huang@intel.com
Cc:     linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, mst@redhat.com,
        jasowang@redhat.com
References: <20221021062734.228881-1-shaoqin.huang@intel.com>
 <20221021062734.228881-3-shaoqin.huang@intel.com>
In-Reply-To: <20221021062734.228881-3-shaoqin.huang@intel.com>
Precedence: bulk

On Thu, 20 Oct 2022 23:27:34 -0700, shaoqin.huang@intel.com wrote:
> From: Shaoqin Huang <shaoqin.huang@intel.com>
>
> Use helper function is_power_of_2() to check if num is power of two.
> Minor readability improvement.
>
> Signed-off-by: Shaoqin Huang <shaoqin.huang@intel.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> ---
>  drivers/virtio/virtio_ring.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 2e7689bb933b..723c4e29e1d3 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -1052,7 +1052,7 @@ static int vring_alloc_queue_split(struct vring_virtqueue_split *vring_split,
>  	dma_addr_t dma_addr;
>
>  	/* We assume num is a power of 2. */
> -	if (num & (num - 1)) {
> +	if (!is_power_of_2(num)) {
>  		dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num);
>  		return -EINVAL;
>  	}
> --
> 2.34.1
>
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