From patchwork Fri Mar 4 09:17:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dust Li X-Patchwork-Id: 12768784 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF0C9C433FE for ; Fri, 4 Mar 2022 09:17:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231334AbiCDJSN (ORCPT ); Fri, 4 Mar 2022 04:18:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237169AbiCDJSL (ORCPT ); Fri, 4 Mar 2022 04:18:11 -0500 Received: from out30-54.freemail.mail.aliyun.com (out30-54.freemail.mail.aliyun.com [115.124.30.54]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97A951A6141; Fri, 4 Mar 2022 01:17:23 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R141e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=dust.li@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0V6BiGIw_1646385440; Received: from localhost(mailfrom:dust.li@linux.alibaba.com fp:SMTPD_---0V6BiGIw_1646385440) by smtp.aliyun-inc.com(127.0.0.1); Fri, 04 Mar 2022 17:17:21 +0800 From: Dust Li To: Karsten Graul , davem@davemloft.net, kuba@kernel.org Cc: Guangguan Wang , Leon Romanovsky , netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org Subject: [PATCH net-next] Revert "net/smc: don't req_notify until all CQEs drained" Date: Fri, 4 Mar 2022 17:17:19 +0800 Message-Id: <20220304091719.48340-1-dust.li@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.3.ge56e4f7 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org This reverts commit a505cce6f7cfaf2aa2385aab7286063c96444526. Leon says: We already discussed that. SMC should be changed to use RDMA CQ pool API drivers/infiniband/core/cq.c. ib_poll_handler() has much better implementation (tracing, IRQ rescheduling, proper error handling) than this SMC variant. Since we will switch to ib_poll_handler() in the future, revert this patch. Link: https://lore.kernel.org/netdev/20220301105332.GA9417@linux.alibaba.com/ Suggested-by: Leon Romanovsky Suggested-by: Karsten Graul Signed-off-by: Dust Li Reviewed-by: Leon Romanovsky --- net/smc/smc_wr.c | 49 +++++++++++++++++++++--------------------------- 1 file changed, 21 insertions(+), 28 deletions(-) diff --git a/net/smc/smc_wr.c b/net/smc/smc_wr.c index 34d616406d51..24be1d03fef9 100644 --- a/net/smc/smc_wr.c +++ b/net/smc/smc_wr.c @@ -137,28 +137,25 @@ static void smc_wr_tx_tasklet_fn(struct tasklet_struct *t) { struct smc_ib_device *dev = from_tasklet(dev, t, send_tasklet); struct ib_wc wc[SMC_WR_MAX_POLL_CQE]; - int i, rc; + int i = 0, rc; + int polled = 0; again: + polled++; do { memset(&wc, 0, sizeof(wc)); rc = ib_poll_cq(dev->roce_cq_send, SMC_WR_MAX_POLL_CQE, wc); + if (polled == 1) { + ib_req_notify_cq(dev->roce_cq_send, + IB_CQ_NEXT_COMP | + IB_CQ_REPORT_MISSED_EVENTS); + } + if (!rc) + break; for (i = 0; i < rc; i++) smc_wr_tx_process_cqe(&wc[i]); - if (rc < SMC_WR_MAX_POLL_CQE) - /* If < SMC_WR_MAX_POLL_CQE, the CQ should have been - * drained, no need to poll again. --Guangguan Wang - */ - break; } while (rc > 0); - - /* IB_CQ_REPORT_MISSED_EVENTS make sure if ib_req_notify_cq() returns - * 0, it is safe to wait for the next event. - * Else we must poll the CQ again to make sure we won't miss any event - */ - if (ib_req_notify_cq(dev->roce_cq_send, - IB_CQ_NEXT_COMP | - IB_CQ_REPORT_MISSED_EVENTS)) + if (polled == 1) goto again; } @@ -481,28 +478,24 @@ static void smc_wr_rx_tasklet_fn(struct tasklet_struct *t) { struct smc_ib_device *dev = from_tasklet(dev, t, recv_tasklet); struct ib_wc wc[SMC_WR_MAX_POLL_CQE]; + int polled = 0; int rc; again: + polled++; do { memset(&wc, 0, sizeof(wc)); rc = ib_poll_cq(dev->roce_cq_recv, SMC_WR_MAX_POLL_CQE, wc); - if (rc > 0) - smc_wr_rx_process_cqes(&wc[0], rc); - if (rc < SMC_WR_MAX_POLL_CQE) - /* If < SMC_WR_MAX_POLL_CQE, the CQ should have been - * drained, no need to poll again. --Guangguan Wang - */ + if (polled == 1) { + ib_req_notify_cq(dev->roce_cq_recv, + IB_CQ_SOLICITED_MASK + | IB_CQ_REPORT_MISSED_EVENTS); + } + if (!rc) break; + smc_wr_rx_process_cqes(&wc[0], rc); } while (rc > 0); - - /* IB_CQ_REPORT_MISSED_EVENTS make sure if ib_req_notify_cq() returns - * 0, it is safe to wait for the next event. - * Else we must poll the CQ again to make sure we won't miss any event - */ - if (ib_req_notify_cq(dev->roce_cq_recv, - IB_CQ_SOLICITED_MASK | - IB_CQ_REPORT_MISSED_EVENTS)) + if (polled == 1) goto again; }