diff mbox series

[09/16] iommu/iommufd: use page allocation function provided by iommu-pages.h

Message ID 20231128204938.1453583-10-pasha.tatashin@soleen.com
State New
Headers
Series IOMMU memory observability |

Commit Message

Pasha Tatashin Nov. 28, 2023, 8:49 p.m. UTC 
  Convert iommu/iommufd/* files to use the new page allocation functions
provided in iommu-pages.h.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
---
 drivers/iommu/iommufd/iova_bitmap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Jason Gunthorpe Nov. 28, 2023, 11:52 p.m. UTC | #1 
On Tue, Nov 28, 2023 at 08:49:31PM +0000, Pasha Tatashin wrote:
> Convert iommu/iommufd/* files to use the new page allocation functions
> provided in iommu-pages.h.
> 
> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
> ---
>  drivers/iommu/iommufd/iova_bitmap.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

This is a short term allocation, it should not be counted, that is why
it is already not using GFP_KERNEL_ACCOUNT.

Jason
Pasha Tatashin Nov. 29, 2023, 9:59 p.m. UTC | #2 
On Tue, Nov 28, 2023 at 6:52 PM Jason Gunthorpe <jgg@ziepe.ca> wrote:
>
> On Tue, Nov 28, 2023 at 08:49:31PM +0000, Pasha Tatashin wrote:
> > Convert iommu/iommufd/* files to use the new page allocation functions
> > provided in iommu-pages.h.
> >
> > Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
> > ---
> >  drivers/iommu/iommufd/iova_bitmap.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
>
> This is a short term allocation, it should not be counted, that is why
> it is already not using GFP_KERNEL_ACCOUNT.

I made this change for completeness. I changed all calls to
get_free_page/alloc_page etc under driver/iommu to use the
iommu_alloc_* variants, this also helps future developers in this area
to use the right allocation functions.
The accounting is implemented using cheap per-cpu counters, so should
not affect the performance, I think it is OK to keep them here.
Jason Gunthorpe Nov. 30, 2023, 12:02 a.m. UTC | #3 
On Wed, Nov 29, 2023 at 04:59:43PM -0500, Pasha Tatashin wrote:
> On Tue, Nov 28, 2023 at 6:52 PM Jason Gunthorpe <jgg@ziepe.ca> wrote:
> >
> > On Tue, Nov 28, 2023 at 08:49:31PM +0000, Pasha Tatashin wrote:
> > > Convert iommu/iommufd/* files to use the new page allocation functions
> > > provided in iommu-pages.h.
> > >
> > > Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
> > > ---
> > >  drivers/iommu/iommufd/iova_bitmap.c | 4 ++--
> > >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > This is a short term allocation, it should not be counted, that is why
> > it is already not using GFP_KERNEL_ACCOUNT.
> 
> I made this change for completeness. I changed all calls to
> get_free_page/alloc_page etc under driver/iommu to use the
> iommu_alloc_* variants, this also helps future developers in this area
> to use the right allocation functions.
> The accounting is implemented using cheap per-cpu counters, so should
> not affect the performance, I think it is OK to keep them here.

Except it is a mis use of an API that should only be used for page
table memory :(

Jason
diff mbox series

Patch

diff --git a/drivers/iommu/iommufd/iova_bitmap.c b/drivers/iommu/iommufd/iova_bitmap.c
index 0a92c9eeaf7f..6b8575b93f17 100644
--- a/drivers/iommu/iommufd/iova_bitmap.c
+++ b/drivers/iommu/iommufd/iova_bitmap.c
@@ -253,7 +253,7 @@  struct iova_bitmap *iova_bitmap_alloc(unsigned long iova, size_t length,
 	bitmap->iova = iova;
 	bitmap->length = length;
 	mapped->iova = iova;
-	mapped->pages = (struct page **)__get_free_page(GFP_KERNEL);
+	mapped->pages = iommu_alloc_page(GFP_KERNEL);
 	if (!mapped->pages) {
 		rc = -ENOMEM;
 		goto err;
@@ -284,7 +284,7 @@  void iova_bitmap_free(struct iova_bitmap *bitmap)
 	iova_bitmap_put(bitmap);
 
 	if (mapped->pages) {
-		free_page((unsigned long)mapped->pages);
+		iommu_free_page(mapped->pages);
 		mapped->pages = NULL;
 	}