ceph: do not carry i_lock for readdir from dcache

We were taking dcache_lock inside of i_lock, which introduces a dependency
not found elsewhere in the kernel, complicationg the vfs locking
scalability work.  Since we don't actually need it here anyway, remove
it.

We only need i_lock to test for the I_COMPLETE flag, so be careful to do
so without dcache_lock held.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index e2e904442ce..1886294e12f 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -400,8 +400,9 @@ static inline bool ceph_i_test(struct inode *inode, unsigned mask)
         struct ceph_inode_info *ci = ceph_inode(inode);
         bool r;
 
-        smp_mb();
+        spin_lock(&inode->i_lock);
         r = (ci->i_ceph_flags & mask) == mask;
+        spin_unlock(&inode->i_lock);
         return r;
 }