[078/129] pnfsblock: dont spinlock when freeing block_dev

[Greg KH]

3.2-stable review patch.  If anyone has any objections, please let me know.

------------------
Content-Length: 1276
Lines: 40

From: Peng Tao <bergwolf@xxxxxxxxx>

commit 93a3844ee0f843b05a1df4b52e1a19ff26b98d24 upstream.

bl_free_block_dev() may sleep. We can not call it with spinlock held.
Besides, there is no need to take bm_lock as we are last user freeing bm_devlist.

Signed-off-by: Peng Tao <peng_tao@xxxxxxx>
Signed-off-by: Benny Halevy <bhalevy@xxxxxxxxxx>
Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 fs/nfs/blocklayout/blocklayout.c |   11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -779,16 +779,13 @@ bl_cleanup_layoutcommit(struct nfs4_layo
 static void free_blk_mountid(struct block_mount_id *mid)
 {
 	if (mid) {
-		struct pnfs_block_dev *dev;
-		spin_lock(&mid->bm_lock);
-		while (!list_empty(&mid->bm_devlist)) {
-			dev = list_first_entry(&mid->bm_devlist,
-					       struct pnfs_block_dev,
-					       bm_node);
+		struct pnfs_block_dev *dev, *tmp;
+
+		/* No need to take bm_lock as we are last user freeing bm_devlist */
+		list_for_each_entry_safe(dev, tmp, &mid->bm_devlist, bm_node) {
 			list_del(&dev->bm_node);
 			bl_free_block_dev(dev);
 		}
-		spin_unlock(&mid->bm_lock);
 		kfree(mid);
 	}
 }


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/