On Fri, Feb 04, 2022 at 07:58:24PM +0000, Matthew Wilcox (Oracle) wrote:
> Add mlock_vma_page() back as a wrapper. Saves a few calls to
> compound_head() and an assertion that the page is not a tail page.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> ---
> mm/folio-compat.c | 5 +++++
> mm/internal.h | 3 ++-
> mm/mlock.c | 18 +++++++++---------
> 3 files changed, 16 insertions(+), 10 deletions(-)
>
> diff --git a/mm/folio-compat.c b/mm/folio-compat.c
> index bcb037d9cec3..9cb0867d5b38 100644
> --- a/mm/folio-compat.c
> +++ b/mm/folio-compat.c
> @@ -169,3 +169,8 @@ void clear_page_mlock(struct page *page)
> {
> folio_end_mlock(page_folio(page));
> }
> +
> +void mlock_vma_page(struct page *page)
> +{
> + mlock_vma_folio(page_folio(page));
> +}
This will make no-mmu unhappy, e.g. arm allnoconfig:
CC mm/folio-compat.o
mm/folio-compat.c:174:6: error: redefinition of 'mlock_vma_page'
174 | void mlock_vma_page(struct page *page)
| ^~~~~~~~~~~~~~
In file included from mm/folio-compat.c:11:
mm/internal.h:501:20: note: previous definition of 'mlock_vma_page' was here
501 | static inline void mlock_vma_page(struct page *page) { }
| ^~~~~~~~~~~~~~
mm/folio-compat.c: In function 'mlock_vma_page':
mm/folio-compat.c:176:2: error: implicit declaration of function 'mlock_vma_folio'; did you mean 'mlock_vma_page'? [-Werror=implicit-function-declaration]
176 | mlock_vma_folio(page_folio(page));
| ^~~~~~~~~~~~~~~
| mlock_vma_page
This also applies to munlock_vma_page() and page_mlock().
For some reason no build yelled about clear_page_mlock()...
> diff --git a/mm/internal.h b/mm/internal.h
> index 041c76a4c284..18b024aa7e59 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -411,7 +411,8 @@ static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
> /*
> * must be called with vma's mmap_lock held for read or write, and page locked.
> */
> -extern void mlock_vma_page(struct page *page);
> +void mlock_vma_page(struct page *page);
> +void mlock_vma_folio(struct folio *folio);
> extern unsigned int munlock_vma_page(struct page *page);
>
> extern int mlock_future_check(struct mm_struct *mm, unsigned long flags,
> diff --git a/mm/mlock.c b/mm/mlock.c
> index ff067d64acc5..d998fd5c84bf 100644
> --- a/mm/mlock.c
> +++ b/mm/mlock.c
> @@ -94,21 +94,21 @@ void folio_end_mlock(struct folio *folio)
> * Mark page as mlocked if not already.
> * If page on LRU, isolate and putback to move to unevictable list.
> */
> -void mlock_vma_page(struct page *page)
> +void mlock_vma_folio(struct folio *folio)
> {
> /* Serialize with page migration */
> - BUG_ON(!PageLocked(page));
> + BUG_ON(!folio_test_locked(folio));
>
> - VM_BUG_ON_PAGE(PageTail(page), page);
> - VM_BUG_ON_PAGE(PageCompound(page) && PageDoubleMap(page), page);
> + VM_BUG_ON_FOLIO(folio_test_large(folio) && folio_test_double_map(folio),
> + folio);
>
> - if (!TestSetPageMlocked(page)) {
> - int nr_pages = thp_nr_pages(page);
> + if (!folio_test_set_mlocked(folio)) {
> + long nr_pages = folio_nr_pages(folio);
>
> - mod_zone_page_state(page_zone(page), NR_MLOCK, nr_pages);
> + zone_stat_mod_folio(folio, NR_MLOCK, nr_pages);
> count_vm_events(UNEVICTABLE_PGMLOCKED, nr_pages);
> - if (!isolate_lru_page(page))
> - putback_lru_page(page);
> + if (!folio_isolate_lru(folio))
> + folio_putback_lru(folio);
> }
> }
>
> --
> 2.34.1
>
>
--
Sincerely yours,
Mike.
