4.14-stable review patch. If anyone has any objections, please let me know.
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From: Sagi Grimberg sagi@grimberg.me
[ Upstream commit 246d8b184c100e8eb6b4e8c88f232c2ed2a4e672 ]
polling the completion queue directly does not interfere with the existing polling logic, hence drop the requirement. Be aware that running ib_process_cq_direct with non IB_POLL_DIRECT CQ may trigger concurrent CQ processing.
This can be used for polling mode ULPs.
Cc: Bart Van Assche bart.vanassche@wdc.com Reported-by: Steve Wise swise@opengridcomputing.com Signed-off-by: Sagi Grimberg sagi@grimberg.me [maxg: added wcs array argument to __ib_process_cq] Signed-off-by: Max Gurtovoy maxg@mellanox.com Signed-off-by: Doug Ledford dledford@redhat.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/infiniband/core/cq.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-)
--- a/drivers/infiniband/core/cq.c +++ b/drivers/infiniband/core/cq.c @@ -25,9 +25,10 @@ #define IB_POLL_FLAGS \ (IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS)
-static int __ib_process_cq(struct ib_cq *cq, int budget) +static int __ib_process_cq(struct ib_cq *cq, int budget, struct ib_wc *poll_wc) { int i, n, completed = 0; + struct ib_wc *wcs = poll_wc ? : cq->wc;
/* * budget might be (-1) if the caller does not @@ -35,9 +36,9 @@ static int __ib_process_cq(struct ib_cq * minimum here. */ while ((n = ib_poll_cq(cq, min_t(u32, IB_POLL_BATCH, - budget - completed), cq->wc)) > 0) { + budget - completed), wcs)) > 0) { for (i = 0; i < n; i++) { - struct ib_wc *wc = &cq->wc[i]; + struct ib_wc *wc = &wcs[i];
if (wc->wr_cqe) wc->wr_cqe->done(cq, wc); @@ -60,18 +61,20 @@ static int __ib_process_cq(struct ib_cq * @cq: CQ to process * @budget: number of CQEs to poll for * - * This function is used to process all outstanding CQ entries on a - * %IB_POLL_DIRECT CQ. It does not offload CQ processing to a different - * context and does not ask for completion interrupts from the HCA. + * This function is used to process all outstanding CQ entries. + * It does not offload CQ processing to a different context and does + * not ask for completion interrupts from the HCA. + * Using direct processing on CQ with non IB_POLL_DIRECT type may trigger + * concurrent processing. * * Note: do not pass -1 as %budget unless it is guaranteed that the number * of completions that will be processed is small. */ int ib_process_cq_direct(struct ib_cq *cq, int budget) { - WARN_ON_ONCE(cq->poll_ctx != IB_POLL_DIRECT); + struct ib_wc wcs[IB_POLL_BATCH];
- return __ib_process_cq(cq, budget); + return __ib_process_cq(cq, budget, wcs); } EXPORT_SYMBOL(ib_process_cq_direct);
@@ -85,7 +88,7 @@ static int ib_poll_handler(struct irq_po struct ib_cq *cq = container_of(iop, struct ib_cq, iop); int completed;
- completed = __ib_process_cq(cq, budget); + completed = __ib_process_cq(cq, budget, NULL); if (completed < budget) { irq_poll_complete(&cq->iop); if (ib_req_notify_cq(cq, IB_POLL_FLAGS) > 0) @@ -105,7 +108,7 @@ static void ib_cq_poll_work(struct work_ struct ib_cq *cq = container_of(work, struct ib_cq, work); int completed;
- completed = __ib_process_cq(cq, IB_POLL_BUDGET_WORKQUEUE); + completed = __ib_process_cq(cq, IB_POLL_BUDGET_WORKQUEUE, NULL); if (completed >= IB_POLL_BUDGET_WORKQUEUE || ib_req_notify_cq(cq, IB_POLL_FLAGS) > 0) queue_work(ib_comp_wq, &cq->work);