summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJoseph Qi <joseph.qi@huawei.com>2014-09-25 16:05:16 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-10-05 14:54:14 -0700
commit64bee3b2dab89d8d9e8a81f9485c24c8314fa4c3 (patch)
treeb0406663a478e1c666798936e2ac6ca1692944a3
parenta0778f706909e867fde6304369a65c7ffad28e1e (diff)
downloadlinux-3.10-64bee3b2dab89d8d9e8a81f9485c24c8314fa4c3.tar.gz
linux-3.10-64bee3b2dab89d8d9e8a81f9485c24c8314fa4c3.tar.bz2
linux-3.10-64bee3b2dab89d8d9e8a81f9485c24c8314fa4c3.zip
ocfs2/dlm: do not get resource spinlock if lockres is new
commit 5760a97c7143c208fa3a8f8cad0ed7dd672ebd28 upstream. There is a deadlock case which reported by Guozhonghua: https://oss.oracle.com/pipermail/ocfs2-devel/2014-September/010079.html This case is caused by &res->spinlock and &dlm->master_lock misordering in different threads. It was introduced by commit 8d400b81cc83 ("ocfs2/dlm: Clean up refmap helpers"). Since lockres is new, it doesn't not require the &res->spinlock. So remove it. Fixes: 8d400b81cc83 ("ocfs2/dlm: Clean up refmap helpers") Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Reviewed-by: joyce.xue <xuejiufei@huawei.com> Reported-by: Guozhonghua <guozhonghua@h3c.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--fs/ocfs2/dlm/dlmmaster.c18
1 files changed, 10 insertions, 8 deletions
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index 33ecbe0e673..2b941113e42 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -653,12 +653,9 @@ void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
clear_bit(bit, res->refmap);
}
-
-void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
+static void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
struct dlm_lock_resource *res)
{
- assert_spin_locked(&res->spinlock);
-
res->inflight_locks++;
mlog(0, "%s: res %.*s, inflight++: now %u, %ps()\n", dlm->name,
@@ -666,6 +663,13 @@ void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
__builtin_return_address(0));
}
+void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res)
+{
+ assert_spin_locked(&res->spinlock);
+ __dlm_lockres_grab_inflight_ref(dlm, res);
+}
+
void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
struct dlm_lock_resource *res)
{
@@ -855,10 +859,8 @@ lookup:
/* finally add the lockres to its hash bucket */
__dlm_insert_lockres(dlm, res);
- /* Grab inflight ref to pin the resource */
- spin_lock(&res->spinlock);
- dlm_lockres_grab_inflight_ref(dlm, res);
- spin_unlock(&res->spinlock);
+ /* since this lockres is new it doesn't not require the spinlock */
+ __dlm_lockres_grab_inflight_ref(dlm, res);
/* get an extra ref on the mle in case this is a BLOCK
* if so, the creator of the BLOCK may try to put the last