LU-3409 llite: silence lockdep warning in ll_md_blocking_ast
Got bellow lockdep warning during tests. It is false alarm though.
[ 1184.479097] =============================================
[ 1184.479187] [ INFO: possible recursive locking detected ]
[ 1184.479277] 3.10.0-rc3+ #13 Tainted: G C
[ 1184.479355] ---------------------------------------------
[ 1184.479444] mkdir/2215 is trying to acquire lock:
[ 1184.479521] (&(&dentry->d_lock)->rlock){+.+...}, at:
[<
ffffffffa06cc27c>] ll_md_blocking_ast+0x55c/0x655 [lustre]
[ 1184.479801]
but task is already holding lock:
[ 1184.479895] (&(&dentry->d_lock)->rlock){+.+...}, at:
[<
ffffffffa06cc1b1>] ll_md_blocking_ast+0x491/0x655 [lustre]
[ 1184.480101]
other info that might help us debug this:
[ 1184.480206] Possible unsafe locking scenario:
[ 1184.480300] CPU0
[ 1184.480340] ----
[ 1184.480380] lock(&(&dentry->d_lock)->rlock);
[ 1184.480458] lock(&(&dentry->d_lock)->rlock);
[ 1184.480536]
*** DEADLOCK ***
[ 1184.480761] May be due to missing lock nesting notation
Signed-off-by: Peng Tao <tao.peng@emc.com>
Change-Id: I34c54ddc7a36dbef77564b1e4f14a16d848b2eaa
Reviewed-on: http://review.whamcloud.com/6469
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Keith Mannthey <keith.mannthey@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>