From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Sagi Grimberg , Bart Van Assche , Max Gurtovoy , Doug Ledford , Sasha Levin Subject: [PATCH AUTOSEL for 4.15 045/189] IB/cq: Don't force IB_POLL_DIRECT poll context for ib_process_cq_direct Date: Mon, 9 Apr 2018 00:17:21 +0000 Message-ID: <20180409001637.162453-45-alexander.levin@microsoft.com> References: <20180409001637.162453-1-alexander.levin@microsoft.com> In-Reply-To: <20180409001637.162453-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Sagi Grimberg [ 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 Reported-by: Steve Wise Signed-off-by: Sagi Grimberg [maxg: added wcs array argument to __ib_process_cq] Signed-off-by: Max Gurtovoy Signed-off-by: Doug Ledford Signed-off-by: Sasha Levin --- drivers/infiniband/core/cq.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/infiniband/core/cq.c b/drivers/infiniband/core/cq.c index f2ae75fa3128..c8c5a5a7f433 100644 --- 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) =20 -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 *pol= l_wc) { int i, n, completed =3D 0; + struct ib_wc *wcs =3D poll_wc ? : cq->wc; =20 /* * budget might be (-1) if the caller does not @@ -35,9 +36,9 @@ static int __ib_process_cq(struct ib_cq *cq, int budget) * minimum here. */ while ((n =3D ib_poll_cq(cq, min_t(u32, IB_POLL_BATCH, - budget - completed), cq->wc)) > 0) { + budget - completed), wcs)) > 0) { for (i =3D 0; i < n; i++) { - struct ib_wc *wc =3D &cq->wc[i]; + struct ib_wc *wc =3D &wcs[i]; =20 if (wc->wr_cqe) wc->wr_cqe->done(cq, wc); @@ -60,18 +61,20 @@ static int __ib_process_cq(struct ib_cq *cq, int budget= ) * @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 !=3D IB_POLL_DIRECT); + struct ib_wc wcs[IB_POLL_BATCH]; =20 - return __ib_process_cq(cq, budget); + return __ib_process_cq(cq, budget, wcs); } EXPORT_SYMBOL(ib_process_cq_direct); =20 @@ -85,7 +88,7 @@ static int ib_poll_handler(struct irq_poll *iop, int budg= et) struct ib_cq *cq =3D container_of(iop, struct ib_cq, iop); int completed; =20 - completed =3D __ib_process_cq(cq, budget); + completed =3D __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 *work) struct ib_cq *cq =3D container_of(work, struct ib_cq, work); int completed; =20 - completed =3D __ib_process_cq(cq, IB_POLL_BUDGET_WORKQUEUE); + completed =3D __ib_process_cq(cq, IB_POLL_BUDGET_WORKQUEUE, NULL); if (completed >=3D IB_POLL_BUDGET_WORKQUEUE || ib_req_notify_cq(cq, IB_POLL_FLAGS) > 0) queue_work(ib_comp_wq, &cq->work); --=20 2.15.1