1 files changed, 8 insertions, 2 deletions

diff --git a/include/linux/mount.h b/include/linux/mount.h
index 1b7e178b0d84..dab69afee2fa 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -43,9 +43,8 @@ struct vfsmount {
         struct super_block *mnt_sb;     /* pointer to superblock */
         struct list_head mnt_mounts;    /* list of children, anchored here */
         struct list_head mnt_child;     /* and going through their mnt_child */
-        atomic_t mnt_count;
         int mnt_flags;
-        int mnt_expiry_mark;            /* true if marked for expiry */
+        /* 4 bytes hole on 64bits arches */
         char *mnt_devname;              /* Name of device e.g. /dev/dsk/hda1 */
         struct list_head mnt_list;
         struct list_head mnt_expire;    /* link in fs-specific expiry list */
@@ -54,6 +53,13 @@ struct vfsmount {
         struct list_head mnt_slave;     /* slave list entry */
         struct vfsmount *mnt_master;    /* slave is on master->mnt_slave_list */
         struct mnt_namespace *mnt_ns;   /* containing namespace */
+        /*
+         * We put mnt_count & mnt_expiry_mark at the end of struct vfsmount
+         * to let these frequently modified fields in a separate cache line
+         * (so that reads of mnt_flags wont ping-pong on SMP machines)
+         */
+        atomic_t mnt_count;
+        int mnt_expiry_mark;            /* true if marked for expiry */
         int mnt_pinned;
 };