On 1/2/22 13:57, Matthew Wilcox (Oracle) wrote:
Replaces three calls to compound_head() with one. This removes the last
user of compound_pincount(), so remove that helper too.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
include/linux/mm.h | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 269b5484d66e..00dcea53bb96 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -947,13 +947,6 @@ static inline int head_compound_pincount(struct page *head)
return atomic_read(compound_pincount_ptr(head));
}
-static inline int compound_pincount(struct page *page)
-{
- VM_BUG_ON_PAGE(!hpage_pincount_available(page), page);
- page = compound_head(page);
- return head_compound_pincount(page);
-}
-
Yes, the only search hit remaining now is in a printk() string in mm/debug.c,
and that is still reasonable wording, even in the new world order, so I
think we're good:
mm/debug.c:96: pr_warn("head:%p order:%u compound_mapcount:%d compound_pincount:%d\n",
static inline void set_compound_order(struct page *page, unsigned int order)
{
page[1].compound_order = order;
@@ -1347,18 +1340,20 @@ void unpin_user_pages(struct page **pages, unsigned long npages);
*/
static inline bool page_maybe_dma_pinned(struct page *page)
{
- if (hpage_pincount_available(page))
- return compound_pincount(page) > 0;
+ struct folio *folio = page_folio(page);
+
+ if (folio_pincount_available(folio))
+ return atomic_read(folio_pincount_ptr(folio)) > 0;
/*
* page_ref_count() is signed. If that refcount overflows, then
* page_ref_count() returns a negative value, and callers will avoid
* further incrementing the refcount.
*
- * Here, for that overflow case, use the signed bit to count a little
+ * Here, for that overflow case, use the sign bit to count a little
* bit higher via unsigned math, and thus still get an accurate result.
*/
- return ((unsigned int)page_ref_count(compound_head(page))) >=
+ return ((unsigned int)folio_ref_count(folio)) >=
GUP_PIN_COUNTING_BIAS;
}
Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>
thanks,
--
John Hubbard
NVIDIA
