From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7B01C4724C for ; Fri, 1 May 2020 13:48:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 889B720836 for ; Fri, 1 May 2020 13:48:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588340905; bh=XmzUmZp9VZrvlkLwm87tHwtyJ72voaQpZBjIlRck0IA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=k58Dz+pz1ezJnc0uJeTmUDeyKYrUj30qRjYTwRJeLtjYQAYwU0mwUC09HXmIoYpUw ZNJKpf3GQhbfm4EC9mpra2AIqTnWqXWyeNzDMg83HPEqP5PtTyQ0tHpUIm0pwUS2G+ E6WDAspbbXt2oiDEdAo566gWM/6aJdUSs6aOfj9o= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731392AbgEANsK (ORCPT ); Fri, 1 May 2020 09:48:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:43224 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731012AbgEANme (ORCPT ); Fri, 1 May 2020 09:42:34 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 443BF2173E; Fri, 1 May 2020 13:42:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588340553; bh=XmzUmZp9VZrvlkLwm87tHwtyJ72voaQpZBjIlRck0IA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1eQ8OTMExwVIo8P8qEdyvCSXvIHWSOZ7AOyZufP19TjICnlOwdbMbYqMxUVic87JL 699J8rL1z4X2qUm2dy5EMGfUXwDQX5SYfyQc2OybzbPjVRWnf9K3T6LVsdBRoiVgk4 wjYqryofxvTk1q/dO9FUHmGXrzpwXr6XlSCmzxFE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Maxim Mikityanskiy , Tariq Toukan , Saeed Mahameed Subject: [PATCH 5.6 041/106] net/mlx5e: Dont trigger IRQ multiple times on XSK wakeup to avoid WQ overruns Date: Fri, 1 May 2020 15:23:14 +0200 Message-Id: <20200501131548.693025914@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200501131543.421333643@linuxfoundation.org> References: <20200501131543.421333643@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Maxim Mikityanskiy commit e7e0004abdd6f83ae4be5613b29ed396beff576c upstream. XSK wakeup function triggers NAPI by posting a NOP WQE to a special XSK ICOSQ. When the application floods the driver with wakeup requests by calling sendto() in a certain pattern that ends up in mlx5e_trigger_irq, the XSK ICOSQ may overflow. Multiple NOPs are not required and won't accelerate the process, so avoid posting a second NOP if there is one already on the way. This way we also avoid increasing the queue size (which might not help anyway). Fixes: db05815b36cb ("net/mlx5e: Add XSK zero-copy support") Signed-off-by: Maxim Mikityanskiy Reviewed-by: Tariq Toukan Signed-off-by: Saeed Mahameed Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlx5/core/en.h | 3 ++- drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c | 3 +++ drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 8 +++++--- drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c | 6 +++++- 4 files changed, 15 insertions(+), 5 deletions(-) --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h @@ -367,6 +367,7 @@ enum { MLX5E_SQ_STATE_AM, MLX5E_SQ_STATE_TLS, MLX5E_SQ_STATE_VLAN_NEED_L2_INLINE, + MLX5E_SQ_STATE_PENDING_XSK_TX, }; struct mlx5e_sq_wqe_info { @@ -950,7 +951,7 @@ void mlx5e_page_release_dynamic(struct m void mlx5e_handle_rx_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe); void mlx5e_handle_rx_cqe_mpwrq(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe); bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq); -void mlx5e_poll_ico_cq(struct mlx5e_cq *cq); +int mlx5e_poll_ico_cq(struct mlx5e_cq *cq); bool mlx5e_post_rx_mpwqes(struct mlx5e_rq *rq); void mlx5e_dealloc_rx_wqe(struct mlx5e_rq *rq, u16 ix); void mlx5e_dealloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix); --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c @@ -33,6 +33,9 @@ int mlx5e_xsk_wakeup(struct net_device * if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &c->xskicosq.state))) return 0; + if (test_and_set_bit(MLX5E_SQ_STATE_PENDING_XSK_TX, &c->xskicosq.state)) + return 0; + spin_lock(&c->xskicosq_lock); mlx5e_trigger_irq(&c->xskicosq); spin_unlock(&c->xskicosq_lock); --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c @@ -587,7 +587,7 @@ bool mlx5e_post_rx_wqes(struct mlx5e_rq return !!err; } -void mlx5e_poll_ico_cq(struct mlx5e_cq *cq) +int mlx5e_poll_ico_cq(struct mlx5e_cq *cq) { struct mlx5e_icosq *sq = container_of(cq, struct mlx5e_icosq, cq); struct mlx5_cqe64 *cqe; @@ -595,11 +595,11 @@ void mlx5e_poll_ico_cq(struct mlx5e_cq * int i; if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state))) - return; + return 0; cqe = mlx5_cqwq_get_cqe(&cq->wq); if (likely(!cqe)) - return; + return 0; /* sq->cc must be updated only after mlx5_cqwq_update_db_record(), * otherwise a cq overrun may occur @@ -648,6 +648,8 @@ void mlx5e_poll_ico_cq(struct mlx5e_cq * sq->cc = sqcc; mlx5_cqwq_update_db_record(&cq->wq); + + return i; } bool mlx5e_post_rx_mpwqes(struct mlx5e_rq *rq) --- a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c @@ -145,7 +145,11 @@ int mlx5e_napi_poll(struct napi_struct * busy |= rq->post_wqes(rq); if (xsk_open) { - mlx5e_poll_ico_cq(&c->xskicosq.cq); + if (mlx5e_poll_ico_cq(&c->xskicosq.cq)) + /* Don't clear the flag if nothing was polled to prevent + * queueing more WQEs and overflowing XSKICOSQ. + */ + clear_bit(MLX5E_SQ_STATE_PENDING_XSK_TX, &c->xskicosq.state); busy |= mlx5e_poll_xdpsq_cq(&xsksq->cq); busy_xsk |= mlx5e_napi_xsk_post(xsksq, xskrq); }