Subject: [PATCH] md:change resync_mismatches to atomic64_t to avoid races

Now that multiple threads can handle stripes, it is safer to
use an atomic64_t for resync_mismatches, to avoid update races.

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index fb5bd607e15c..146749b277c6 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2011,7 +2011,7 @@ static void sync_request_write(struct mddev *mddev, struct r10bio *r10_bio)
                                         break;
                         if (j == vcnt)
                                 continue;
-                        mddev->resync_mismatches += r10_bio->sectors;
+                        atomic64_add(r10_bio->sectors, &mddev->resync_mismatches);
                         if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
                                 /* Don't fix anything. */
                                 continue;