diff mbox series

[v11,01/33] mm: Convert get_page_unless_zero() to return bool

Message ID 20210614201435.1379188-2-willy@infradead.org (mailing list archive)
State New
Headers show
Series Memory folios | expand

Commit Message

Matthew Wilcox June 14, 2021, 8:14 p.m. UTC
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>
---
 include/linux/mm.h       | 2 +-
 include/linux/page_ref.h | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

Comments

Christoph Hellwig June 15, 2021, 6:24 a.m. UTC | #1
On Mon, Jun 14, 2021 at 09:14:03PM +0100, Matthew Wilcox (Oracle) wrote:
> 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.

Strange.  Anyway, this looks like the right type, so:

Reviewed-by: Christoph Hellwig <hch@lst.de>
David Howells June 16, 2021, 9:19 a.m. UTC | #2
Matthew Wilcox (Oracle) <willy@infradead.org> wrote:

> 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: David Howells <dhowells@redhat.com>
diff mbox series

Patch

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 9c9430f063a7..877eb8730eea 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -757,7 +757,7 @@  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);