From: Matthew Wilcox <willy@infradead.org>
Date: Wed, 22 Nov 2017 13:34:58 +0000 (-0500)
Subject: shmem: Convert shmem_confirm_swap to XArray
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=a12831bf4293d38518e41b80dd897af0122bb268;p=openwrt%2Fstaging%2Fblogic.git

shmem: Convert shmem_confirm_swap to XArray

xa_load has its own RCU locking, so we can eliminate it here.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
---

diff --git a/mm/shmem.c b/mm/shmem.c
index 5697c8fecdfc..ce91569426f3 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -349,12 +349,7 @@ static int shmem_replace_entry(struct address_space *mapping,
 static bool shmem_confirm_swap(struct address_space *mapping,
 			       pgoff_t index, swp_entry_t swap)
 {
-	void *item;
-
-	rcu_read_lock();
-	item = radix_tree_lookup(&mapping->i_pages, index);
-	rcu_read_unlock();
-	return item == swp_to_radix_entry(swap);
+	return xa_load(&mapping->i_pages, index) == swp_to_radix_entry(swap);
 }
 
 /*