On Tue, Jul 30, 2019 at 08:52:01AM +0300, Christoph Hellwig wrote:
> Stub out the whole function when CONFIG_TRANSPARENT_HUGEPAGE is not set
> to make the function easier to read.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> mm/hmm.c | 18 +++++++++---------
> 1 file changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/mm/hmm.c b/mm/hmm.c
> index 4d3bd41b6522..f4e90ea5779f 100644
> +++ b/mm/hmm.c
> @@ -455,13 +455,10 @@ static inline uint64_t pmd_to_hmm_pfn_flags(struct hmm_range *range, pmd_t pmd)
> range->flags[HMM_PFN_VALID];
> }
>
> -static int hmm_vma_handle_pmd(struct mm_walk *walk,
> - unsigned long addr,
> - unsigned long end,
> - uint64_t *pfns,
> - pmd_t pmd)
> -{
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> +static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr,
> + unsigned long end, uint64_t *pfns, pmd_t pmd)
> +{
> struct hmm_vma_walk *hmm_vma_walk = walk->private;
> struct hmm_range *range = hmm_vma_walk->range;
> struct dev_pagemap *pgmap = NULL;
> @@ -490,11 +487,14 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk,
> put_dev_pagemap(pgmap);
> hmm_vma_walk->last = end;
> return 0;
> -#else
> - /* If THP is not enabled then we should never reach this
This old comment says we should never get here
> +}
> +#else /* CONFIG_TRANSPARENT_HUGEPAGE */
> +static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr,
> + unsigned long end, uint64_t *pfns, pmd_t pmd)
> +{
> return -EINVAL;
So could we just do
#define hmm_vma_handle_pmd NULL
?
At the very least this seems like a WARN_ON too?
Jason
