xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

RDMA/cxgb3: Serialize calls to CQ's comp_handler

Browse Source 
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>
This commit is contained in:
Kumar Sanghvi
2011-10-24 21:20:22 +05:30
committed by Roland Dreier
parent 976d167615
commit f7cc25d018
4 changed files with 20 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/infiniband/hw/cxgb3/iwch_qp.c
View File

@@ -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;
}