diff options
| author | Ralph Campbell <ralph.campbell@qlogic.com> | 2007-07-06 12:48:23 -0700 |
|---|---|---|
| committer | Roland Dreier <rolandd@cisco.com> | 2007-07-09 20:12:26 -0700 |
| commit | 4fc570bcbe77f823aae183dd824869f79e74cc97 (patch) | |
| tree | 3955946608a973b06db8b7e5b3ec319354a6fa73 /drivers/infiniband/hw/ipath/ipath_srq.c | |
| parent | 06cc85086e6896939f8c68f8518224748f6b0b2f (diff) | |
IB/ipath: Add barrier before updating WC head in shared memory
Add a barrier to make sure the CPU doesn't reorder writes to memory,
since user programs can be polling on the head index update and the
entry should be written before that.
Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Diffstat (limited to 'drivers/infiniband/hw/ipath/ipath_srq.c')
| -rw-r--r-- | drivers/infiniband/hw/ipath/ipath_srq.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/ipath/ipath_srq.c b/drivers/infiniband/hw/ipath/ipath_srq.c index 14cbbd633d3..40c36ec1901 100644 --- a/drivers/infiniband/hw/ipath/ipath_srq.c +++ b/drivers/infiniband/hw/ipath/ipath_srq.c @@ -80,6 +80,8 @@ int ipath_post_srq_receive(struct ib_srq *ibsrq, struct ib_recv_wr *wr, wqe->num_sge = wr->num_sge; for (i = 0; i < wr->num_sge; i++) wqe->sg_list[i] = wr->sg_list[i]; + /* Make sure queue entry is written before the head index. */ + smp_wmb(); wq->head = next; spin_unlock_irqrestore(&srq->rq.lock, flags); } |