Re: [PATCH v2 2/2] iova: Remove magazine BUG_ON() checks

Jerry Snitselaar
2022-09-05T15:06:59Z

On Mon, Sep 05, 2022 at 05:11:23PM +0800, John Garry wrote:
> Two of the magazine helpers have BUG_ON() checks, as follows:
> - iova_magazine_pop() - here we ensure that the mag is not empty. However we
> already ensure that in the only caller, __iova_rcache_get().
> - iova_magazine_push() - here we ensure that the mag is not full. However
> we already ensure that in the only caller, __iova_rcache_insert().
>
> As described, the two bug checks are pointless so drop them.
>
> Signed-off-by: John Garry <john.garry@huawei.com>
> Acked-by: Robin Murphy <robin.murphy@arm.com>

Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com

> ---
> drivers/iommu/iova.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
> index 580fdf669922..8aece052ce72 100644
> --- a/drivers/iommu/iova.c
> +++ b/drivers/iommu/iova.c
> @@ -694,8 +694,6 @@ static unsigned long iova_magazine_pop(struct iova_magazine *mag,
> int i;
> unsigned long pfn;
>
> - BUG_ON(iova_magazine_empty(mag));
> -
> /* Only fall back to the rbtree if we have no suitable pfns at all */
> for (i = mag->size - 1; mag->pfns[i] > limit_pfn; i--)
> if (i == 0)
> @@ -710,8 +708,6 @@ static unsigned long iova_magazine_pop(struct iova_magazine *mag,
>
> static void iova_magazine_push(struct iova_magazine *mag, unsigned long pfn)
> {
> - BUG_ON(iova_magazine_full(mag));
> -
> mag->pfns[mag->size++] = pfn;
> }
>
> --
> 2.35.3
>