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From:   =?UTF-8?Q?Christian_G=C3=B6ttsche?= <cgzones@googlemail.com>
Date:   Tue, 18 Jul 2023 17:10:14 +0200
Message-ID: <CAJ2a_Dd+CUggq0gtaeuPSP+iCrqUH08cCwU95AYGXxv5TBWSuA@mail.gmail.com>
Subject: Re: [PATCH 1/5] mm: introduce vma_is_stack() and vma_is_heap()
To:     Kefeng Wang <wangkefeng.wang@huawei.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org, linux-perf-users@vger.kernel.org,
        selinux@vger.kernel.org
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On Wed, 12 Jul 2023 at 16:25, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
>
> Introduce the two helpers for general use.
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
>  include/linux/mm.h | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 1462cf15badf..0bbeb31ac750 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -926,6 +926,18 @@ static inline bool vma_is_anonymous(struct vm_area_struct *vma)
>         return !vma->vm_ops;
>  }
>
> +static inline bool vma_is_heap(struct vm_area_struct *vma)

What about declaring the parameters const to document in code these
functions do not modify any state, and allow callers to pass pointers
to const?

> +{
> +       return vma->vm_start <= vma->vm_mm->brk &&
> +               vma->vm_end >= vma->vm_mm->start_brk;
> +}
> +
> +static inline bool vma_is_stack(struct vm_area_struct *vma)
> +{
> +       return vma->vm_start <= vma->vm_mm->start_stack &&
> +              vma->vm_end >= vma->vm_mm->start_stack;
> +}
> +
>  static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
>  {
>         int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
> --
> 2.41.0
>