Re: [PATCH v2 24/28] gup: Convert gup_huge_pgd() to use a folio

From: John Hubbard
Date: Tue Jan 11 2022 - 02:38:50 EST


On 1/9/22 20:24, Matthew Wilcox (Oracle) wrote:
Use the new folio-based APIs. This was the last user of
try_grab_compound_head(), so remove it.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
mm/gup.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)

Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>


thanks,
--
John Hubbard
NVIDIA


diff --git a/mm/gup.c b/mm/gup.c
index 7b7bf8361558..b5786e83c418 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -146,12 +146,6 @@ struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags)
return NULL;
}
-static inline struct page *try_grab_compound_head(struct page *page,
- int refs, unsigned int flags)
-{
- return &try_grab_folio(page, refs, flags)->page;
-}
-
static void gup_put_folio(struct folio *folio, int refs, unsigned int flags)
{
if (flags & FOLL_PIN) {
@@ -2563,7 +2557,8 @@ static int gup_huge_pgd(pgd_t orig, pgd_t *pgdp, unsigned long addr,
struct page **pages, int *nr)
{
int refs;
- struct page *head, *page;
+ struct page *page;
+ struct folio *folio;
if (!pgd_access_permitted(orig, flags & FOLL_WRITE))
return 0;
@@ -2573,17 +2568,17 @@ static int gup_huge_pgd(pgd_t orig, pgd_t *pgdp, unsigned long addr,
page = nth_page(pgd_page(orig), (addr & ~PGDIR_MASK) >> PAGE_SHIFT);
refs = record_subpages(page, addr, end, pages + *nr);
- head = try_grab_compound_head(pgd_page(orig), refs, flags);
- if (!head)
+ folio = try_grab_folio(page, refs, flags);
+ if (!folio)
return 0;
if (unlikely(pgd_val(orig) != pgd_val(*pgdp))) {
- put_compound_head(head, refs, flags);
+ gup_put_folio(folio, refs, flags);
return 0;
}
*nr += refs;
- SetPageReferenced(head);
+ folio_set_referenced(folio);
return 1;
}