diff options
| author | Mike Marciniszyn <mike.marciniszyn@intel.com> | 2019-06-07 08:25:31 -0400 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@mellanox.com> | 2019-06-11 17:06:45 -0300 |
| commit | da9de5f8527f4b9efc82f967d29a583318c034c7 (patch) | |
| tree | 336cbfb929371d36fb606e8d769a2dea105bdc4f /drivers/infiniband | |
| parent | 5f90677ed31963abb184ee08ebee4a4a68225dd8 (diff) | |
IB/hfi1: Close PSM sdma_progress sleep window
The call to sdma_progress() is called outside the wait lock.
In this case, there is a race condition where sdma_progress() can return
false and the sdma_engine can idle. If that happens, there will be no
more sdma interrupts to cause the wakeup and the user_sdma xmit will hang.
Fix by moving the lock to enclose the sdma_progress() call.
Also, delete busycount. The need for this was removed by:
commit bcad29137a97 ("IB/hfi1: Serve the most starved iowait entry first")
Cc: <stable@vger.kernel.org>
Fixes: 7724105686e7 ("IB/hfi1: add driver files")
Reviewed-by: Gary Leshner <Gary.S.Leshner@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'drivers/infiniband')
| -rw-r--r-- | drivers/infiniband/hw/hfi1/user_sdma.c | 12 | ||||
| -rw-r--r-- | drivers/infiniband/hw/hfi1/user_sdma.h | 1 |
2 files changed, 4 insertions, 9 deletions
diff --git a/drivers/infiniband/hw/hfi1/user_sdma.c b/drivers/infiniband/hw/hfi1/user_sdma.c index 8bfbc6d7ea34..fd754a16475a 100644 --- a/drivers/infiniband/hw/hfi1/user_sdma.c +++ b/drivers/infiniband/hw/hfi1/user_sdma.c @@ -130,20 +130,16 @@ static int defer_packet_queue( { struct hfi1_user_sdma_pkt_q *pq = container_of(wait->iow, struct hfi1_user_sdma_pkt_q, busy); - struct user_sdma_txreq *tx = - container_of(txreq, struct user_sdma_txreq, txreq); - if (sdma_progress(sde, seq, txreq)) { - if (tx->busycount++ < MAX_DEFER_RETRY_COUNT) - goto eagain; - } + write_seqlock(&sde->waitlock); + if (sdma_progress(sde, seq, txreq)) + goto eagain; /* * We are assuming that if the list is enqueued somewhere, it * is to the dmawait list since that is the only place where * it is supposed to be enqueued. */ xchg(&pq->state, SDMA_PKT_Q_DEFERRED); - write_seqlock(&sde->waitlock); if (list_empty(&pq->busy.list)) { iowait_get_priority(&pq->busy); iowait_queue(pkts_sent, &pq->busy, &sde->dmawait); @@ -151,6 +147,7 @@ static int defer_packet_queue( write_sequnlock(&sde->waitlock); return -EBUSY; eagain: + write_sequnlock(&sde->waitlock); return -EAGAIN; } @@ -804,7 +801,6 @@ static int user_sdma_send_pkts(struct user_sdma_request *req, u16 maxpkts) tx->flags = 0; tx->req = req; - tx->busycount = 0; INIT_LIST_HEAD(&tx->list); /* diff --git a/drivers/infiniband/hw/hfi1/user_sdma.h b/drivers/infiniband/hw/hfi1/user_sdma.h index 14dfd757dafd..4d8510b0fc38 100644 --- a/drivers/infiniband/hw/hfi1/user_sdma.h +++ b/drivers/infiniband/hw/hfi1/user_sdma.h @@ -245,7 +245,6 @@ struct user_sdma_txreq { struct list_head list; struct user_sdma_request *req; u16 flags; - unsigned int busycount; u16 seqnum; }; |