Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20221021163703.3218176-1-jthoughton@google.com> <20221021163703.3218176-3-jthoughton@google.com>
In-Reply-To: <20221021163703.3218176-3-jthoughton@google.com>
From:   Mina Almasry <almasrymina@google.com>
Date:   Wed, 7 Dec 2022 15:13:50 -0800
Message-ID: <CAHS8izMyO=AJcZAKRNVfWS2-AQvzxk6mNsTgK_6u7V=P09Ykcg@mail.gmail.com>
Subject: Re: [RFC PATCH v2 02/47] hugetlb: remove mk_huge_pte; it is unused
To:     James Houghton <jthoughton@google.com>
Cc:     Mike Kravetz <mike.kravetz@oracle.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Peter Xu <peterx@redhat.com>,
        David Hildenbrand <david@redhat.com>,
        David Rientjes <rientjes@google.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        "Zach O'Keefe" <zokeefe@google.com>,
        Manish Mishra <manish.mishra@nutanix.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        "Dr . David Alan Gilbert" <dgilbert@redhat.com>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Baolin Wang <baolin.wang@linux.alibaba.com>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Yang Shi <shy828301@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Fri, Oct 21, 2022 at 9:37 AM James Houghton <jthoughton@google.com> wrote:
>
> mk_huge_pte is unused and not necessary. pte_mkhuge is the appropriate
> function to call to create a HugeTLB PTE (see
> Documentation/mm/arch_pgtable_helpers.rst).
>
> It is being removed now to avoid complicating the implementation of
> HugeTLB high-granularity mapping.
>
> Signed-off-by: James Houghton <jthoughton@google.com>

Acked-by: Mina Almasry <almasrymina@google.com>

> ---
>  arch/s390/include/asm/hugetlb.h | 5 -----
>  include/asm-generic/hugetlb.h   | 5 -----
>  mm/debug_vm_pgtable.c           | 2 +-
>  mm/hugetlb.c                    | 7 +++----
>  4 files changed, 4 insertions(+), 15 deletions(-)
>
> diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
> index ccdbccfde148..c34893719715 100644
> --- a/arch/s390/include/asm/hugetlb.h
> +++ b/arch/s390/include/asm/hugetlb.h
> @@ -77,11 +77,6 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
>         set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte));
>  }
>
> -static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
> -{
> -       return mk_pte(page, pgprot);
> -}
> -
>  static inline int huge_pte_none(pte_t pte)
>  {
>         return pte_none(pte);
> diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
> index a57d667addd2..aab9e46fa628 100644
> --- a/include/asm-generic/hugetlb.h
> +++ b/include/asm-generic/hugetlb.h
> @@ -5,11 +5,6 @@
>  #include <linux/swap.h>
>  #include <linux/swapops.h>
>
> -static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
> -{
> -       return mk_pte(page, pgprot);
> -}
> -
>  static inline unsigned long huge_pte_write(pte_t pte)
>  {
>         return pte_write(pte);
> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
> index 2b61fde8c38c..10573a283a12 100644
> --- a/mm/debug_vm_pgtable.c
> +++ b/mm/debug_vm_pgtable.c
> @@ -929,7 +929,7 @@ static void __init hugetlb_basic_tests(struct pgtable_debug_args *args)
>          * as it was previously derived from a real kernel symbol.
>          */
>         page = pfn_to_page(args->fixed_pmd_pfn);
> -       pte = mk_huge_pte(page, args->page_prot);
> +       pte = mk_pte(page, args->page_prot);
>
>         WARN_ON(!huge_pte_dirty(huge_pte_mkdirty(pte)));
>         WARN_ON(!huge_pte_write(huge_pte_mkwrite(huge_pte_wrprotect(pte))));
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 650761cdd2f6..20a111b532aa 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -4728,11 +4728,10 @@ static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
>         unsigned int shift = huge_page_shift(hstate_vma(vma));
>
>         if (writable) {
> -               entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page,
> -                                        vma->vm_page_prot)));
> +               entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_pte(page,
> +                                               vma->vm_page_prot)));
>         } else {
> -               entry = huge_pte_wrprotect(mk_huge_pte(page,
> -                                          vma->vm_page_prot));
> +               entry = huge_pte_wrprotect(mk_pte(page, vma->vm_page_prot));
>         }
>         entry = pte_mkyoung(entry);
>         entry = arch_make_huge_pte(entry, shift, vma->vm_flags);
> --
> 2.38.0.135.g90850a2211-goog
>