Re: [PATCH 05/16] huge tmpfs: move shmem_huge_enabled() upwards

From: Yang Shi <shy828301@gmail.com>
To: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Shakeel Butt <shakeelb@google.com>,
	"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
	Miaohe Lin <linmiaohe@huawei.com>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	Michal Hocko <mhocko@suse.com>, Rik van Riel <riel@surriel.com>,
	Christoph Hellwig <hch@infradead.org>,
	Matthew Wilcox <willy@infradead.org>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	Alexey Gladkov <legion@kernel.org>,
	Chris Wilson <chris@chris-wilson.co.uk>,
	Matthew Auld <matthew.auld@intel.com>,
	Linux FS-devel Mailing List <linux-fsdevel@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-api@vger.kernel.org, Linux MM <linux-mm@kvack.org>
Subject: Re: [PATCH 05/16] huge tmpfs: move shmem_huge_enabled() upwards
Date: Fri, 30 Jul 2021 14:57:03 -0700	[thread overview]
Message-ID: <CAHbLzkqN0L9S3shxU-2PJBeqbKwt4knFN2_Nh-tAcfq=QfLJDw@mail.gmail.com> (raw)
In-Reply-To: <a859bb7f-7978-7e3a-eb32-88224cfa50dc@google.com>

On Fri, Jul 30, 2021 at 12:39 AM Hugh Dickins <hughd@google.com> wrote:
>
> shmem_huge_enabled() is about to be enhanced into shmem_is_huge(),
> so that it can be used more widely throughout: before making functional
> changes, shift it to its final position (to avoid forward declaration).
>
> Signed-off-by: Hugh Dickins <hughd@google.com>

Reviewed-by: Yang Shi <shy828301@gmail.com>

> ---
>  mm/shmem.c | 72 ++++++++++++++++++++++++++----------------------------
>  1 file changed, 35 insertions(+), 37 deletions(-)
>
> diff --git a/mm/shmem.c b/mm/shmem.c
> index c6fa6f4f2db8..740d48ef1eb5 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -476,6 +476,41 @@ static bool shmem_confirm_swap(struct address_space *mapping,
>
>  static int shmem_huge __read_mostly;
>
> +bool shmem_huge_enabled(struct vm_area_struct *vma)
> +{
> +       struct inode *inode = file_inode(vma->vm_file);
> +       struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
> +       loff_t i_size;
> +       pgoff_t off;
> +
> +       if ((vma->vm_flags & VM_NOHUGEPAGE) ||
> +           test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
> +               return false;
> +       if (shmem_huge == SHMEM_HUGE_FORCE)
> +               return true;
> +       if (shmem_huge == SHMEM_HUGE_DENY)
> +               return false;
> +       switch (sbinfo->huge) {
> +       case SHMEM_HUGE_NEVER:
> +               return false;
> +       case SHMEM_HUGE_ALWAYS:
> +               return true;
> +       case SHMEM_HUGE_WITHIN_SIZE:
> +               off = round_up(vma->vm_pgoff, HPAGE_PMD_NR);
> +               i_size = round_up(i_size_read(inode), PAGE_SIZE);
> +               if (i_size >= HPAGE_PMD_SIZE &&
> +                               i_size >> PAGE_SHIFT >= off)
> +                       return true;
> +               fallthrough;
> +       case SHMEM_HUGE_ADVISE:
> +               /* TODO: implement fadvise() hints */
> +               return (vma->vm_flags & VM_HUGEPAGE);
> +       default:
> +               VM_BUG_ON(1);
> +               return false;
> +       }
> +}
> +
>  #if defined(CONFIG_SYSFS)
>  static int shmem_parse_huge(const char *str)
>  {
> @@ -3995,43 +4030,6 @@ struct kobj_attribute shmem_enabled_attr =
>         __ATTR(shmem_enabled, 0644, shmem_enabled_show, shmem_enabled_store);
>  #endif /* CONFIG_TRANSPARENT_HUGEPAGE && CONFIG_SYSFS */
>
> -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> -bool shmem_huge_enabled(struct vm_area_struct *vma)
> -{
> -       struct inode *inode = file_inode(vma->vm_file);
> -       struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
> -       loff_t i_size;
> -       pgoff_t off;
> -
> -       if ((vma->vm_flags & VM_NOHUGEPAGE) ||
> -           test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
> -               return false;
> -       if (shmem_huge == SHMEM_HUGE_FORCE)
> -               return true;
> -       if (shmem_huge == SHMEM_HUGE_DENY)
> -               return false;
> -       switch (sbinfo->huge) {
> -               case SHMEM_HUGE_NEVER:
> -                       return false;
> -               case SHMEM_HUGE_ALWAYS:
> -                       return true;
> -               case SHMEM_HUGE_WITHIN_SIZE:
> -                       off = round_up(vma->vm_pgoff, HPAGE_PMD_NR);
> -                       i_size = round_up(i_size_read(inode), PAGE_SIZE);
> -                       if (i_size >= HPAGE_PMD_SIZE &&
> -                                       i_size >> PAGE_SHIFT >= off)
> -                               return true;
> -                       fallthrough;
> -               case SHMEM_HUGE_ADVISE:
> -                       /* TODO: implement fadvise() hints */
> -                       return (vma->vm_flags & VM_HUGEPAGE);
> -               default:
> -                       VM_BUG_ON(1);
> -                       return false;
> -       }
> -}
> -#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
> -
>  #else /* !CONFIG_SHMEM */
>
>  /*
> --
> 2.26.2
>