diff options
authorZach Brown <zach.brown@oracle.com>2006-07-04 02:57:52 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-07-04 10:24:57 -0700
commita46f9484f8926aacb2e79a0e1676de3a6a6fbae8 (patch)
parent[PATCH] Fix copying of pgdat array on each node for ia64 memory hotplug (diff)
[PATCH] mthca: initialize send and receive queue locks separately
mthca: initialize send and receive queue locks separately lockdep identifies a lock by the call site of its initialization. By initializing the send and receive queue locks in mthca_wq_init() we confuse lockdep. It warns that that the ordered acquiry of both locks in mthca_modify_qp() is recursive acquiry of one lock: ============================================= [ INFO: possible recursive locking detected ] --------------------------------------------- modprobe/1192 is trying to acquire lock: (&wq->lock){....}, at: [<f892b4db>] mthca_modify_qp+0x60/0xa7b [ib_mthca] but task is already holding lock: (&wq->lock){....}, at: [<f892b4ce>] mthca_modify_qp+0x53/0xa7b [ib_mthca] Initializing the locks separately in mthca_alloc_qp_common() stops the warning and will let lockdep enforce proper ordering on paths that acquire both locks. Signed-off-by: Zach Brown <zach.brown@oracle.com> Cc: Roland Dreier <rolandd@cisco.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/infiniband/hw/mthca/mthca_qp.c b/drivers/infiniband/hw/mthca/mthca_qp.c
index 16c387d8170c..490fc783bb0c 100644
--- a/drivers/infiniband/hw/mthca/mthca_qp.c
+++ b/drivers/infiniband/hw/mthca/mthca_qp.c
@@ -224,7 +224,7 @@ static void *get_send_wqe(struct mthca_qp *qp, int n)
static void mthca_wq_init(struct mthca_wq *wq)
- spin_lock_init(&wq->lock);
+ /* mthca_alloc_qp_common() initializes the locks */
wq->next_ind = 0;
wq->last_comp = wq->max - 1;
wq->head = 0;
@@ -1114,6 +1114,9 @@ static int mthca_alloc_qp_common(struct mthca_dev *dev,
qp->sq_policy = send_policy;
+ /* these are initialized separately so lockdep can tell them apart */
+ spin_lock_init(&qp->sq.lock);
+ spin_lock_init(&qp->rq.lock);
ret = mthca_map_memfree(dev, qp);
if (ret)