diff options
| author | Kumar Sanghvi <kumaras@chelsio.com> | 2011-10-24 19:50:22 +0400 |
|---|---|---|
| committer | Roland Dreier <roland@purestorage.com> | 2011-10-31 22:33:17 +0400 |
| commit | f7cc25d018f1e9af6767ee7774bbe83452e9fdf4 (patch) | |
| tree | 43d10d7038f8295b4ad92e938b0c705db5ce58b3 /drivers/infiniband/hw/cxgb3/iwch_qp.c | |
| parent | 976d167615b64e14bc1491ca51d424e2ba9a5e84 (diff) | |
| download | linux-f7cc25d018f1e9af6767ee7774bbe83452e9fdf4.tar.xz | |
RDMA/cxgb3: Serialize calls to CQ's comp_handler
iw_cxgb3 has a potential problem where a CQ's comp_handler can get
called simultaneously from different places in iw_cxgb3 driver. This
does not comply with Documentation/infiniband/core_locking.txt, which
states that at a given point of time, there should be only one
callback per CQ should be active.
Such problem was reported by Parav Pandit <Parav.Pandit@Emulex.Com>
for iw_cxgb4 driver. Based on discussion between Parav Pandit and
Steve Wise, this patch fixes the above problem by serializing the
calls to a CQ's comp_handler using a spin_lock.
Signed-off-by: Kumar Sanghvi <kumaras@chelsio.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Diffstat (limited to 'drivers/infiniband/hw/cxgb3/iwch_qp.c')
| -rw-r--r-- | drivers/infiniband/hw/cxgb3/iwch_qp.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/infiniband/hw/cxgb3/iwch_qp.c b/drivers/infiniband/hw/cxgb3/iwch_qp.c index ecd313f359a4..bea5839d89ee 100644 --- a/drivers/infiniband/hw/cxgb3/iwch_qp.c +++ b/drivers/infiniband/hw/cxgb3/iwch_qp.c @@ -822,8 +822,11 @@ static void __flush_qp(struct iwch_qp *qhp, struct iwch_cq *rchp, flushed = cxio_flush_rq(&qhp->wq, &rchp->cq, count); spin_unlock(&qhp->lock); spin_unlock_irqrestore(&rchp->lock, *flag); - if (flushed) + if (flushed) { + spin_lock_irqsave(&rchp->comp_handler_lock, *flag); (*rchp->ibcq.comp_handler)(&rchp->ibcq, rchp->ibcq.cq_context); + spin_unlock_irqrestore(&rchp->comp_handler_lock, *flag); + } /* locking hierarchy: cq lock first, then qp lock. */ spin_lock_irqsave(&schp->lock, *flag); @@ -833,8 +836,11 @@ static void __flush_qp(struct iwch_qp *qhp, struct iwch_cq *rchp, flushed = cxio_flush_sq(&qhp->wq, &schp->cq, count); spin_unlock(&qhp->lock); spin_unlock_irqrestore(&schp->lock, *flag); - if (flushed) + if (flushed) { + spin_lock_irqsave(&schp->comp_handler_lock, *flag); (*schp->ibcq.comp_handler)(&schp->ibcq, schp->ibcq.cq_context); + spin_unlock_irqrestore(&schp->comp_handler_lock, *flag); + } /* deref */ if (atomic_dec_and_test(&qhp->refcnt)) @@ -853,11 +859,15 @@ static void flush_qp(struct iwch_qp *qhp, unsigned long *flag) if (qhp->ibqp.uobject) { cxio_set_wq_in_error(&qhp->wq); cxio_set_cq_in_error(&rchp->cq); + spin_lock_irqsave(&rchp->comp_handler_lock, *flag); (*rchp->ibcq.comp_handler)(&rchp->ibcq, rchp->ibcq.cq_context); + spin_unlock_irqrestore(&rchp->comp_handler_lock, *flag); if (schp != rchp) { cxio_set_cq_in_error(&schp->cq); + spin_lock_irqsave(&schp->comp_handler_lock, *flag); (*schp->ibcq.comp_handler)(&schp->ibcq, schp->ibcq.cq_context); + spin_unlock_irqrestore(&schp->comp_handler_lock, *flag); } return; } |