linux-kernel - [PATCH v4 42/73] shmem: Convert shmem_confirm

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Message-Id: <20171206004159.3755-43-willy@infradead.org>
Date:   Tue,  5 Dec 2017 16:41:28 -0800
From:   Matthew Wilcox <willy@...radead.org>
To:     unlisted-recipients:; (no To-header on input)
Cc:     Matthew Wilcox <mawilcox@...rosoft.com>,
        Ross Zwisler <ross.zwisler@...ux.intel.com>,
        Jens Axboe <axboe@...nel.dk>,
        Rehas Sachdeva <aquannie@...il.com>, linux-mm@...ck.org,
        linux-fsdevel@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net,
        linux-nilfs@...r.kernel.org, linux-btrfs@...r.kernel.org,
        linux-xfs@...r.kernel.org, linux-usb@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH v4 42/73] shmem: Convert shmem_confirm_swap to XArray

From: Matthew Wilcox <mawilcox@...rosoft.com>

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

Signed-off-by: Matthew Wilcox <mawilcox@...rosoft.com>
---
 mm/shmem.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index fad6c9e7402e..654f367aca90 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -348,12 +348,7 @@ static int shmem_xa_replace(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->pages, index);
-	rcu_read_unlock();
-	return item == swp_to_radix_entry(swap);
+	return xa_load(&mapping->pages, index) == swp_to_radix_entry(swap);
 }
 
 /*
-- 
2.15.0