block: fix non-atomic access to genhd inflight structures

After the stack plugging introduction, these are called lockless.
Ensure that the counters are updated atomically.

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index 9c21119512b9..ac546975031f 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -290,7 +290,8 @@ ssize_t part_inflight_show(struct device *dev,
 {
         struct hd_struct *p = dev_to_part(dev);
 
-        return sprintf(buf, "%8u %8u\n", p->in_flight[0], p->in_flight[1]);
+        return sprintf(buf, "%8u %8u\n", atomic_read(&p->in_flight[0]),
+                atomic_read(&p->in_flight[1]));
 }
 
 #ifdef CONFIG_FAIL_MAKE_REQUEST