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>

diff --git a/lustre/llite/dcache.c b/lustre/llite/dcache.c
index 328a687..029e621 100644 (file)
--- a/lustre/llite/dcache.c
+++ b/lustre/llite/dcache.c
@@ -329,7 +329,7 @@ void ll_invalidate_aliases(struct inode *inode)
                         libcfs_debug_dumpstack(NULL);
                 }
 
-               d_lustre_invalidate(dentry);
+               d_lustre_invalidate(dentry, 0);
        }
        ll_unlock_dcache(inode);
 

diff --git a/lustre/llite/file.c b/lustre/llite/file.c
index 94f7784..a216652 100644 (file)
--- a/lustre/llite/file.c
+++ b/lustre/llite/file.c
@@ -2779,7 +2779,7 @@ int __ll_inode_revalidate_it(struct dentry *dentry, struct lookup_intent *it,
                    here to preserve get_cwd functionality on 2.6.
                    Bug 10503 */
                if (!dentry->d_inode->i_nlink)
-                       d_lustre_invalidate(dentry);
+                       d_lustre_invalidate(dentry, 0);
 
                 ll_lookup_finish_locks(&oit, dentry);
         } else if (!ll_have_md_lock(dentry->d_inode, &ibits, LCK_MINMODE)) {

diff --git a/lustre/llite/llite_internal.h b/lustre/llite/llite_internal.h
index d150bb6..daaa371 100644 (file)
--- a/lustre/llite/llite_internal.h
+++ b/lustre/llite/llite_internal.h
@@ -1585,13 +1585,14 @@ static inline void __d_lustre_invalidate(struct dentry *dentry)
  * ll_md_blocking_ast), unhash this dentry, and let dcache to reclaim it later;
  * else dput() of the last refcount will unhash this dentry and kill it.
  */
-static inline void d_lustre_invalidate(struct dentry *dentry)
+static inline void d_lustre_invalidate(struct dentry *dentry, int nested)
 {
        CDEBUG(D_DENTRY, "invalidate dentry %.*s (%p) parent %p inode %p "
               "refc %d\n", dentry->d_name.len, dentry->d_name.name, dentry,
               dentry->d_parent, dentry->d_inode, d_refcount(dentry));
 
-       spin_lock(&dentry->d_lock);
+       spin_lock_nested(&dentry->d_lock,
+                        nested ? DENTRY_D_LOCK_NESTED : DENTRY_D_LOCK_NORMAL);
        __d_lustre_invalidate(dentry);
        if (d_refcount(dentry) == 0)
                __d_drop(dentry);

diff --git a/lustre/llite/namei.c b/lustre/llite/namei.c
index a14c86c..7383c7c 100644 (file)
--- a/lustre/llite/namei.c
+++ b/lustre/llite/namei.c
@@ -187,7 +187,7 @@ static void ll_invalidate_negative_children(struct inode *dir)
                                                 &dentry->d_subdirs,
                                                 d_u.d_child) {
                                if (child->d_inode == NULL)
-                                       d_lustre_invalidate(child);
+                                       d_lustre_invalidate(child, 1);
                        }
                }
                spin_unlock(&dentry->d_lock);