From patchwork Mon Nov 27 21:16:32 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steve Wise X-Patchwork-Id: 10097075 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8DE7260210 for ; Wed, 6 Dec 2017 20:08:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7FED529B55 for ; Wed, 6 Dec 2017 20:08:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7370629F23; Wed, 6 Dec 2017 20:08:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.5 required=2.0 tests=BAYES_00, DATE_IN_PAST_96_XX, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D07D629B55 for ; Wed, 6 Dec 2017 20:08:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752488AbdLFUIK (ORCPT ); Wed, 6 Dec 2017 15:08:10 -0500 Received: from linode.aoot.com ([69.164.194.13]:47710 "EHLO linode.aoot.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751946AbdLFUIK (ORCPT ); Wed, 6 Dec 2017 15:08:10 -0500 Received: by linode.aoot.com (Postfix, from userid 0) id AF14C87CA; Wed, 6 Dec 2017 14:08:09 -0600 (CST) From: Steve Wise Date: Mon, 27 Nov 2017 13:16:32 -0800 Subject: [PATCH rdma-rc] iw_cxgb4: only insert drain cqes if wq is flushed To: dledford@redhat.com, jgg@ziepe.ca Cc: linux-rdma@vger.kernel.org Message-Id: <20171206200809.AF14C87CA@linode.aoot.com> Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Only insert our special drain CQEs to support ib_drain_sq/rq() after the wq is flushed. Otherwise, existing but not yet polled CQEs can be returned out of order to the user application. This can happen when the QP has exited RTS but not yet flushed the QP, which can happen during a normal close (vs abortive close). In addition never count the drain CQEs when determining how many CQEs need to be synthesized during the flush operation. This latter issue should never happen if the QP is properly flushed before inserting the drain CQE, but I wanted to avoid corrupting the CQ state. So we handle it and log a warning once. Fixes: 4fe7c2962e11 ("iw_cxgb4: refactor sq/rq drain logic") Signed-off-by: Steve Wise Cc: stable@vger.kernel.org --- drivers/infiniband/hw/cxgb4/cq.c | 5 +++++ drivers/infiniband/hw/cxgb4/qp.c | 14 ++++++++++++-- 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/cxgb4/cq.c b/drivers/infiniband/hw/cxgb4/cq.c index ea55e95cd2c5..b7bfc536e00f 100644 --- a/drivers/infiniband/hw/cxgb4/cq.c +++ b/drivers/infiniband/hw/cxgb4/cq.c @@ -395,6 +395,11 @@ void c4iw_flush_hw_cq(struct c4iw_cq *chp) static int cqe_completes_wr(struct t4_cqe *cqe, struct t4_wq *wq) { + if (CQE_OPCODE(cqe) == C4IW_DRAIN_OPCODE) { + WARN_ONCE(1, "Unexpected DRAIN CQE qp id %u!\n", wq->sq.qid); + return 0; + } + if (CQE_OPCODE(cqe) == FW_RI_TERMINATE) return 0; diff --git a/drivers/infiniband/hw/cxgb4/qp.c b/drivers/infiniband/hw/cxgb4/qp.c index 355e288ec969..38bddd02a943 100644 --- a/drivers/infiniband/hw/cxgb4/qp.c +++ b/drivers/infiniband/hw/cxgb4/qp.c @@ -868,7 +868,12 @@ int c4iw_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, qhp = to_c4iw_qp(ibqp); spin_lock_irqsave(&qhp->lock, flag); - if (t4_wq_in_error(&qhp->wq)) { + + /* + * If the qp has been flushed, then just insert a special + * drain cqe. + */ + if (qhp->wq.flushed) { spin_unlock_irqrestore(&qhp->lock, flag); complete_sq_drain_wr(qhp, wr); return err; @@ -1011,7 +1016,12 @@ int c4iw_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr, qhp = to_c4iw_qp(ibqp); spin_lock_irqsave(&qhp->lock, flag); - if (t4_wq_in_error(&qhp->wq)) { + + /* + * If the qp has been flushed, then just insert a special + * drain cqe. + */ + if (qhp->wq.flushed) { spin_unlock_irqrestore(&qhp->lock, flag); complete_rq_drain_wr(qhp, wr); return err;