zfsonlinux/zfs — pull request #1557 by casualfish (2013-06-29 07:21:57+00:00)
Title: Improve code in arc_buf_remove_ref

When we remove references of arc bufs in the arc_anon state we
needn't take its header's hash_lock, so postpone it to where we
really need it to avoid unnecessary invocations of function buf_hash.

Signed-off-by: Ying Zhu