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

Jason Gunthorpe
2023-11-30T00:03:27Z

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