Re: [PATCH v2 16/28] mm: Remove page_cache_add_speculative() and page_cache_get_speculative()

From: John Hubbard
Date: Tue Jan 11 2022 - 00:14:15 EST


On 1/9/22 20:23, Matthew Wilcox (Oracle) wrote:
These wrappers have no more callers, so delete them.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
include/linux/mm.h | 7 +++----
include/linux/pagemap.h | 11 -----------
2 files changed, 3 insertions(+), 15 deletions(-)

Confirmed that at this point in the series there are no more callers.

Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>


thanks,
--
John Hubbard
NVIDIA


diff --git a/include/linux/mm.h b/include/linux/mm.h
index d3769897c8ac..b249156f7cf1 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1291,10 +1291,9 @@ static inline void put_page(struct page *page)
* applications that don't have huge page reference counts, this won't be an
* issue.
*
- * Locking: the lockless algorithm described in page_cache_get_speculative()
- * and page_cache_gup_pin_speculative() provides safe operation for
- * get_user_pages and page_mkclean and other calls that race to set up page
- * table entries.
+ * Locking: the lockless algorithm described in folio_try_get_rcu()
+ * provides safe operation for get_user_pages(), page_mkclean() and
+ * other calls that race to set up page table entries.
*/
#define GUP_PIN_COUNTING_BIAS (1U << 10)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 704cb1b4b15d..4a63176b6417 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -283,17 +283,6 @@ static inline struct inode *folio_inode(struct folio *folio)
return folio->mapping->host;
}
-static inline bool page_cache_add_speculative(struct page *page, int count)
-{
- VM_BUG_ON_PAGE(PageTail(page), page);
- return folio_ref_try_add_rcu((struct folio *)page, count);
-}
-
-static inline bool page_cache_get_speculative(struct page *page)
-{
- return page_cache_add_speculative(page, 1);
-}
-
/**
* folio_attach_private - Attach private data to a folio.
* @folio: Folio to attach data to.