[PATCH v13 51/72] shmem: Convert shmem_free_swap to XArray

[Matthew Wilcox]

From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>

Since we are conditionally storing NULL in the XArray, we do not need
to allocate memory and the GFP flags will be unused.

Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
 mm/shmem.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 09452ca79220..9dbbdd5dee30 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -653,7 +653,7 @@ static void shmem_delete_from_page_cache(struct page *page, void *radswap)
 }
 
 /*
- * Remove swap entry from radix tree, free the swap and its page cache.
+ * Remove swap entry from page cache, free the swap and its page cache.
  */
 static int shmem_free_swap(struct address_space *mapping,
 			   pgoff_t index, void *radswap)
@@ -661,7 +661,7 @@ static int shmem_free_swap(struct address_space *mapping,
 	void *old;
 
 	xa_lock_irq(&mapping->i_pages);
-	old = radix_tree_delete_item(&mapping->i_pages, index, radswap);
+	old = __xa_cmpxchg(&mapping->i_pages, index, radswap, NULL, 0);
 	xa_unlock_irq(&mapping->i_pages);
 	if (old != radswap)
 		return -ENOENT;
-- 
2.17.1