From patchwork Thu Jun 22 16:22:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Long Li X-Patchwork-Id: 13289412 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 965918494 for ; Thu, 22 Jun 2023 16:22:43 +0000 (UTC) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 0F2141FE8; Thu, 22 Jun 2023 09:22:42 -0700 (PDT) Received: by linux.microsoft.com (Postfix, from userid 1004) id 2637D21C20A2; Thu, 22 Jun 2023 09:22:41 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 2637D21C20A2 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxonhyperv.com; s=default; t=1687450961; bh=bpRMX3RMcGhusT5aTzmC87ILJ8BKTaQbhSuw8yFpVNw=; h=From:To:Cc:Subject:Date:From; b=Gg655xF/W9QuTA6iSWGzMfa5Y88+NWxxT7CxBWMTLltOohhrLituO8sn8cLto9Dk6 30D4NeQsfwrBTpt87SSf2MbgvhMp2ohNQKMf7pl/qFiz5KazqQ1UwR77ZMXVIxhYtz PHtjkgh1X3mUVQ9UYhvIlrIOuV40neEgq7+iMQhI= From: longli@linuxonhyperv.com To: Jason Gunthorpe , Leon Romanovsky , Ajay Sharma , Dexuan Cui , "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: linux-rdma@vger.kernel.org, linux-hyperv@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Long Li , stable@vger.kernel.org Subject: [PATCH v2] net: mana: Batch ringing RX queue doorbell on receiving packets Date: Thu, 22 Jun 2023 09:22:36 -0700 Message-Id: <1687450956-6407-1-git-send-email-longli@linuxonhyperv.com> X-Mailer: git-send-email 1.8.3.1 X-Spam-Status: No, score=-11.6 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS,T_SCC_BODY_TEXT_LINE, USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: X-Patchwork-Delegate: kuba@kernel.org From: Long Li It's inefficient to ring the doorbell page every time a WQE is posted to the received queue. Move the code for ringing doorbell page to where after we have posted all WQEs to the receive queue during a callback from napi_poll(). Tests showed no regression in network latency benchmarks. Cc: stable@vger.kernel.org Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)") Signed-off-by: Long Li Reviewed-by: Haiyang Zhang Reviewed-by: Dexuan Cui --- Change log: v2: Check for comp_read > 0 as it might be negative on completion error. Set rq.wqe_cnt to 0 according to BNIC spec. drivers/net/ethernet/microsoft/mana/gdma_main.c | 5 ++++- drivers/net/ethernet/microsoft/mana/mana_en.c | 10 ++++++++-- 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c index 8f3f78b68592..ef11d09a3655 100644 --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c @@ -300,8 +300,11 @@ static void mana_gd_ring_doorbell(struct gdma_context *gc, u32 db_index, void mana_gd_wq_ring_doorbell(struct gdma_context *gc, struct gdma_queue *queue) { + /* BNIC Spec specifies that client should set 0 for rq.wqe_cnt + * This value is not used in sq + */ mana_gd_ring_doorbell(gc, queue->gdma_dev->doorbell, queue->type, - queue->id, queue->head * GDMA_WQE_BU_SIZE, 1); + queue->id, queue->head * GDMA_WQE_BU_SIZE, 0); } void mana_gd_ring_cq(struct gdma_queue *cq, u8 arm_bit) diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index cd4d5ceb9f2d..1d8abe63fcb8 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -1383,8 +1383,8 @@ static void mana_post_pkt_rxq(struct mana_rxq *rxq) recv_buf_oob = &rxq->rx_oobs[curr_index]; - err = mana_gd_post_and_ring(rxq->gdma_rq, &recv_buf_oob->wqe_req, - &recv_buf_oob->wqe_inf); + err = mana_gd_post_work_request(rxq->gdma_rq, &recv_buf_oob->wqe_req, + &recv_buf_oob->wqe_inf); if (WARN_ON_ONCE(err)) return; @@ -1654,6 +1654,12 @@ static void mana_poll_rx_cq(struct mana_cq *cq) mana_process_rx_cqe(rxq, cq, &comp[i]); } + if (comp_read > 0) { + struct gdma_context *gc = rxq->gdma_rq->gdma_dev->gdma_context; + + mana_gd_wq_ring_doorbell(gc, rxq->gdma_rq); + } + if (rxq->xdp_flush) xdp_do_flush(); }