mm: Turn can_split_huge_page() into can_split_folio()

This function already required a head page to be passed, so this
just adds type-safety and removes a few implicit calls to
compound_head().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2022-02-04 14:13:31 -05:00
parent e0cd5e7ffa
commit d4b4084ac3
3 changed files with 13 additions and 12 deletions

View File

@ -185,7 +185,7 @@ void prep_transhuge_page(struct page *page);
void free_transhuge_page(struct page *page); void free_transhuge_page(struct page *page);
bool is_transparent_hugepage(struct page *page); bool is_transparent_hugepage(struct page *page);
bool can_split_huge_page(struct page *page, int *pextra_pins); bool can_split_folio(struct folio *folio, int *pextra_pins);
int split_huge_page_to_list(struct page *page, struct list_head *list); int split_huge_page_to_list(struct page *page, struct list_head *list);
static inline int split_huge_page(struct page *page) static inline int split_huge_page(struct page *page)
{ {
@ -387,7 +387,7 @@ static inline bool is_transparent_hugepage(struct page *page)
#define thp_get_unmapped_area NULL #define thp_get_unmapped_area NULL
static inline bool static inline bool
can_split_huge_page(struct page *page, int *pextra_pins) can_split_folio(struct folio *folio, int *pextra_pins)
{ {
BUILD_BUG(); BUILD_BUG();
return false; return false;

View File

@ -2516,18 +2516,19 @@ int page_trans_huge_mapcount(struct page *page)
} }
/* Racy check whether the huge page can be split */ /* Racy check whether the huge page can be split */
bool can_split_huge_page(struct page *page, int *pextra_pins) bool can_split_folio(struct folio *folio, int *pextra_pins)
{ {
int extra_pins; int extra_pins;
/* Additional pins from page cache */ /* Additional pins from page cache */
if (PageAnon(page)) if (folio_test_anon(folio))
extra_pins = PageSwapCache(page) ? thp_nr_pages(page) : 0; extra_pins = folio_test_swapcache(folio) ?
folio_nr_pages(folio) : 0;
else else
extra_pins = thp_nr_pages(page); extra_pins = folio_nr_pages(folio);
if (pextra_pins) if (pextra_pins)
*pextra_pins = extra_pins; *pextra_pins = extra_pins;
return total_mapcount(page) == page_count(page) - extra_pins - 1; return folio_mapcount(folio) == folio_ref_count(folio) - extra_pins - 1;
} }
/* /*
@ -2619,7 +2620,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
* Racy check if we can split the page, before unmap_page() will * Racy check if we can split the page, before unmap_page() will
* split PMDs * split PMDs
*/ */
if (!can_split_huge_page(head, &extra_pins)) { if (!can_split_folio(folio, &extra_pins)) {
ret = -EBUSY; ret = -EBUSY;
goto out_unlock; goto out_unlock;
} }
@ -2928,7 +2929,7 @@ static int split_huge_pages_pid(int pid, unsigned long vaddr_start,
goto next; goto next;
total++; total++;
if (!can_split_huge_page(compound_head(page), NULL)) if (!can_split_folio(page_folio(page), NULL))
goto next; goto next;
if (!trylock_page(page)) if (!trylock_page(page))

View File

@ -1703,18 +1703,18 @@ static unsigned int shrink_page_list(struct list_head *page_list,
if (!PageSwapCache(page)) { if (!PageSwapCache(page)) {
if (!(sc->gfp_mask & __GFP_IO)) if (!(sc->gfp_mask & __GFP_IO))
goto keep_locked; goto keep_locked;
if (page_maybe_dma_pinned(page)) if (folio_maybe_dma_pinned(folio))
goto keep_locked; goto keep_locked;
if (PageTransHuge(page)) { if (PageTransHuge(page)) {
/* cannot split THP, skip it */ /* cannot split THP, skip it */
if (!can_split_huge_page(page, NULL)) if (!can_split_folio(folio, NULL))
goto activate_locked; goto activate_locked;
/* /*
* Split pages without a PMD map right * Split pages without a PMD map right
* away. Chances are some or all of the * away. Chances are some or all of the
* tail pages can be freed without IO. * tail pages can be freed without IO.
*/ */
if (!compound_mapcount(page) && if (!folio_entire_mapcount(folio) &&
split_folio_to_list(folio, split_folio_to_list(folio,
page_list)) page_list))
goto activate_locked; goto activate_locked;