[PATCH v13 001/137] mm: Convert get_page_unless_zero() to return bool

Matthew Wilcox (Oracle)
2021-07-12T03:09:08Z

atomic_add_unless() returns bool, so remove the widening casts to int
in page_ref_add_unless() and get_page_unless_zero(). This causes gcc
to produce slightly larger code in isolate_migratepages_block(), but
it's not clear that it's worse code. Net +19 bytes of text.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
include/linux/mm.h | 2 +-
include/linux/page_ref.h | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 57453dba41b9..02851931e958 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -755,7 +755,7 @@ static inline int put_page_testzero(struct page *page)
* This can be called when MMU is off so it must not access
* any of the virtual mappings.
*/
-static inline int get_page_unless_zero(struct page *page)
+static inline bool get_page_unless_zero(struct page *page)
{
return page_ref_add_unless(page, 1, 0);
}
diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h
index 7ad46f45df39..3a799de8ad52 100644
--- a/include/linux/page_ref.h
+++ b/include/linux/page_ref.h
@@ -161,9 +161,9 @@ static inline int page_ref_dec_return(struct page *page)
return ret;
}

-static inline int page_ref_add_unless(struct page *page, int nr, int u)
+static inline bool page_ref_add_unless(struct page *page, int nr, int u)
{
- int ret = atomic_add_unless(&page->_refcount, nr, u);
+ bool ret = atomic_add_unless(&page->_refcount, nr, u);

if (page_ref_tracepoint_active(page_ref_mod_unless))
__page_ref_mod_unless(page, nr, ret);
--
2.30.2