On 4/4/22 22:02, Yang Shi wrote:
> Since commit a4aeaa06d45e ("mm: khugepaged: skip huge page collapse for
> special files"), khugepaged just collapses THP for regular file which is
> the intended usecase for readonly fs THP. Only show regular file as THP
> eligible accordingly.
>
> And make file_thp_enabled() available for khugepaged too in order to remove
> duplicate code.
>
> Acked-by: Song Liu <song@xxxxxxxxxx>
> Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
> ---
> include/linux/huge_mm.h | 14 ++++++++++++++
> mm/huge_memory.c | 11 ++---------
> mm/khugepaged.c | 9 ++-------
> 3 files changed, 18 insertions(+), 16 deletions(-)
>
> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> index 2999190adc22..62a6f667850d 100644
> --- a/include/linux/huge_mm.h
> +++ b/include/linux/huge_mm.h
> @@ -172,6 +172,20 @@ static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
> return false;
> }
>
> +static inline bool file_thp_enabled(struct vm_area_struct *vma)
> +{
> + struct inode *inode;
> +
> + if (!vma->vm_file)
> + return false;
> +
> + inode = vma->vm_file->f_inode;
> +
> + return (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS)) &&
> + (vma->vm_flags & VM_EXEC) &&
> + !inode_is_open_for_write(inode) && S_ISREG(inode->i_mode);
> +}
> +
> bool transparent_hugepage_active(struct vm_area_struct *vma);
>
> #define transparent_hugepage_use_zero_page() \
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 2fe38212e07c..183b793fd28e 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -68,13 +68,6 @@ static atomic_t huge_zero_refcount;
> struct page *huge_zero_page __read_mostly;
> unsigned long huge_zero_pfn __read_mostly = ~0UL;
>
> -static inline bool file_thp_enabled(struct vm_area_struct *vma)
> -{
> - return transhuge_vma_enabled(vma, vma->vm_flags) && vma->vm_file &&
> - !inode_is_open_for_write(vma->vm_file->f_inode) &&
> - (vma->vm_flags & VM_EXEC);
> -}
> -
> bool transparent_hugepage_active(struct vm_area_struct *vma)
> {
> /* The addr is used to check if the vma size fits */
> @@ -86,8 +79,8 @@ bool transparent_hugepage_active(struct vm_area_struct *vma)
> return __transparent_hugepage_enabled(vma);
> if (vma_is_shmem(vma))
> return shmem_huge_enabled(vma);
> - if (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS))
> - return file_thp_enabled(vma);
> + if (transhuge_vma_enabled(vma, vma->vm_flags) && file_thp_enabled(vma))
> + return true;
>
> return false;
> }
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 964a4d2c942a..609c1bc0a027 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -464,13 +464,8 @@ static bool hugepage_vma_check(struct vm_area_struct *vma,
> return false;
>
> /* Only regular file is valid */
> - if (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && vma->vm_file &&
> - (vm_flags & VM_EXEC)) {
> - struct inode *inode = vma->vm_file->f_inode;
> -
> - return !inode_is_open_for_write(inode) &&
> - S_ISREG(inode->i_mode);
> - }
> + if (file_thp_enabled(vma))
> + return true;
>
> if (!vma->anon_vma || vma->vm_ops)
> return false;
