2022-08-17 10:20:36

by John Garry

Subject: [PATCH 1/3] iova: Remove some magazine pointer NULL checks

Since commit 32e92d9f6f87 ("iommu/iova: Separate out rcache init") it
has not been possible to have NULL CPU rcache "loaded" or "prev" magazine
pointers. As such, the checks in iova_magazine_full(),
iova_magazine_empty(), and iova_magazine_free_pfns() may be dropped.

Signed-off-by: John Garry <[email protected]>
---
drivers/iommu/iova.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 47d1983dfa2a..580fdf669922 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -661,9 +661,6 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
unsigned long flags;
int i;

- if (!mag)
- return;
-
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);

for (i = 0 ; i < mag->size; ++i) {
@@ -683,12 +680,12 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)

static bool iova_magazine_full(struct iova_magazine *mag)
{
- return (mag && mag->size == IOVA_MAG_SIZE);
+ return mag->size == IOVA_MAG_SIZE;
}

static bool iova_magazine_empty(struct iova_magazine *mag)
{
- return (!mag || mag->size == 0);
+ return mag->size == 0;
}

static unsigned long iova_magazine_pop(struct iova_magazine *mag,
--
2.35.3

2022-08-17 11:22:38

by Robin Murphy

Subject: Re: [PATCH 1/3] iova: Remove some magazine pointer NULL checks

On 2022-08-17 11:09, John Garry wrote:
> Since commit 32e92d9f6f87 ("iommu/iova: Separate out rcache init") it
> has not been possible to have NULL CPU rcache "loaded" or "prev" magazine
> pointers. As such, the checks in iova_magazine_full(),
> iova_magazine_empty(), and iova_magazine_free_pfns() may be dropped.

Reviewed-by: Robin Murphy <[email protected]>

> Signed-off-by: John Garry <[email protected]>
> ---
> drivers/iommu/iova.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
> index 47d1983dfa2a..580fdf669922 100644
> --- a/drivers/iommu/iova.c
> +++ b/drivers/iommu/iova.c
> @@ -661,9 +661,6 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
> unsigned long flags;
> int i;
>
> - if (!mag)
> - return;
> -
> spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
>
> for (i = 0 ; i < mag->size; ++i) {
> @@ -683,12 +680,12 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
>
> static bool iova_magazine_full(struct iova_magazine *mag)
> {
> - return (mag && mag->size == IOVA_MAG_SIZE);
> + return mag->size == IOVA_MAG_SIZE;
> }
>
> static bool iova_magazine_empty(struct iova_magazine *mag)
> {
> - return (!mag || mag->size == 0);
> + return mag->size == 0;
> }
>
> static unsigned long iova_magazine_pop(struct iova_magazine *mag,