Btrfs: use RCU instead of a spinlock to protect the root node
authorChris Mason <chris.mason@oracle.com>
Wed, 23 Mar 2011 18:54:42 +0000 (14:54 -0400)
committerroot <Chris Mason chris.mason@oracle.com>
Mon, 28 Mar 2011 09:37:22 +0000 (05:37 -0400)
commit240f62c8756df285da11469259b3900f32883168
treeeb973ef95389a9511c137c7c26248dfd04a2495f
parentc0da7aa1a2d8fcafe271a7077599253c8ed94bb2
Btrfs: use RCU instead of a spinlock to protect the root node

The pointer to the extent buffer for the root of each tree
is protected by a spinlock so that we can safely read the pointer
and take a reference on the extent buffer.

But now that the extent buffers are freed via RCU, we can safely
use rcu_read_lock instead.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
fs/btrfs/ctree.c