tree a1a1355da23b7448afdc851f7a211f2b3492d6e5
parent d5a7df0649fa6a1e7800785d760e2c7d7a3204de
author Wengang Wang <wen.gang.wang@oracle.com> 1274098844 +0800
committer Joel Becker <joel.becker@oracle.com> 1274226094 -0700

ocfs2:dlm: avoid dlm->ast_lock lockres->spinlock dependency break

Currently we process a dirty lockres with the lockres->spinlock taken. While
during the process, we may need to lock on dlm->ast_lock. This breaks the
dependency of dlm->ast_lock(lock first) and lockres->spinlock(lock second).

This patch fixes the problem.
Since we can't release lockres->spinlock, we have to take dlm->ast_lock
just before taking the lockres->spinlock and release it after lockres->spinlock
is released. And use __dlm_queue_bast()/__dlm_queue_ast(), the nolock version,
in dlm_shuffle_lists(). There are no too many locks on a lockres, so there is no
performance harm.

Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>