From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 417D147049; Mon, 15 Dec 2025 19:43:53 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 11BB44029A; Mon, 15 Dec 2025 19:43:53 +0100 (CET) Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) by mails.dpdk.org (Postfix) with ESMTP id 08EBB40151 for ; Mon, 15 Dec 2025 19:43:50 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1765824231; x=1797360231; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Qyo11zMzqAOnyh5QwWDByPQgpLYCv5QBCMc9RE1PHcE=; b=DJZs+tK+Fw9+mBf341WdJBEVPDZYNjRcJSor2NdscrESNGLnzyUd04Ia Qe+UgHJAu4tPMhLASPlVjRh3sKsmB8pHEg5QQEMlg+9IfuaHKToa4cs7C SMWR0IxafGGBeKgnQ0HKzyH1m7/PbO+skbeINUpVrRbKIkOLAgvd8dzzI ckMG7/AXh+sK04x4nYUOe5HU+kv68bX330cxMxuXIPO2OEgpW3Sr5/SIb xwdRRhLEL8tB2u2PX+sSiw8ozDlVr3xgohyvPhZclxvEj89qle6TlIVYF hlBshugRmyFKF/QNZ2wknZOVj0TG6aeiZDU4NMrC7NjmFInxkl1eFieg6 Q==; X-CSE-ConnectionGUID: GPsamReWRCidC7RZ3IaZAA== X-CSE-MsgGUID: 3S1uykmDR+yt8824gaVUJA== X-IronPort-AV: E=McAfee;i="6800,10657,11643"; a="70312983" X-IronPort-AV: E=Sophos;i="6.21,151,1763452800"; d="scan'208";a="70312983" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Dec 2025 10:43:50 -0800 X-CSE-ConnectionGUID: oOmrHQ8IS1mgzieya36ypg== X-CSE-MsgGUID: 647ygaynRvODTGv/nZRlBA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,151,1763452800"; d="scan'208";a="197426904" Received: from silpixa00401385.ir.intel.com ([10.20.224.226]) by fmviesa007.fm.intel.com with ESMTP; 15 Dec 2025 10:43:46 -0800 From: Bruce Richardson To: dev@dpdk.org Cc: Bruce Richardson Subject: [PATCH v2] net/intel: improve Rx descriptor ring size checks Date: Mon, 15 Dec 2025 18:43:42 +0000 Message-ID: <20251215184342.1722960-1-bruce.richardson@intel.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251215173543.1707960-1-bruce.richardson@intel.com> References: <20251215173543.1707960-1-bruce.richardson@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org The default Rx ring size checks did not account for the fact that the port would not work correctly if the Rx ring size was only twice the free threshold size or less, so add in a new check for this. This would generally only apply in cases where very small rings sizes are being used, for example, with default Rx free thresh of 32, only ring size of 64 would cause issues. Signed-off-by: Bruce Richardson --- v2: add in extra error message for the small queue size case, to help make users aware of what setting they need to use to fix things. --- drivers/net/intel/cpfl/cpfl_rxtx.c | 10 ++++++++++ drivers/net/intel/i40e/i40e_rxtx.c | 10 ++++++++++ drivers/net/intel/iavf/iavf_rxtx.c | 23 ++++++++--------------- drivers/net/intel/ice/ice_rxtx.c | 10 ++++++++++ drivers/net/intel/idpf/idpf_rxtx.c | 10 ++++++++++ drivers/net/intel/ixgbe/ixgbe_rxtx.c | 10 ++++++++++ 6 files changed, 58 insertions(+), 15 deletions(-) diff --git a/drivers/net/intel/cpfl/cpfl_rxtx.c b/drivers/net/intel/cpfl/cpfl_rxtx.c index 453ec975d5..d42b1142c2 100644 --- a/drivers/net/intel/cpfl/cpfl_rxtx.c +++ b/drivers/net/intel/cpfl/cpfl_rxtx.c @@ -362,6 +362,16 @@ cpfl_rx_queue_setup(struct rte_eth_dev *dev, uint16_t queue_idx, if (idpf_qc_rx_thresh_check(nb_desc, rx_free_thresh) != 0) return -EINVAL; + /* Check that ring size is > 2 * rx_free_thresh */ + if (nb_desc <= 2 * rx_free_thresh) { + PMD_INIT_LOG(ERR, "rx ring size (%u) must be > 2 * rx_free_thresh (%u)", + nb_desc, rx_free_thresh); + if (rx_free_thresh == CPFL_DEFAULT_RX_FREE_THRESH) + PMD_INIT_LOG(ERR, "To use ring sizes of %u or smaller, reduce rx_free_thresh", + CPFL_DEFAULT_RX_FREE_THRESH * 2); + return -EINVAL; + } + /* Free memory if needed */ if (dev->data->rx_queues[queue_idx] != NULL) { cpfl_rx_queue_release(dev->data->rx_queues[queue_idx]); diff --git a/drivers/net/intel/i40e/i40e_rxtx.c b/drivers/net/intel/i40e/i40e_rxtx.c index 255414dd03..430f367eab 100644 --- a/drivers/net/intel/i40e/i40e_rxtx.c +++ b/drivers/net/intel/i40e/i40e_rxtx.c @@ -2113,6 +2113,16 @@ i40e_dev_rx_queue_setup(struct rte_eth_dev *dev, return -EINVAL; } + /* Check that ring size is > 2 * rx_free_thresh */ + if (nb_desc <= 2 * rx_conf->rx_free_thresh) { + PMD_DRV_LOG(ERR, "rx ring size (%u) must be > 2 * rx_free_thresh (%u)", + nb_desc, rx_conf->rx_free_thresh); + if (nb_desc == I40E_MIN_RING_DESC) + PMD_DRV_LOG(ERR, "To use the minimum ring size (%u), reduce rx_free_thresh to a lower value (recommended %u)", + I40E_MIN_RING_DESC, I40E_MIN_RING_DESC / 4); + return -EINVAL; + } + /* Free memory if needed */ if (dev->data->rx_queues[queue_idx]) { i40e_rx_queue_release(dev->data->rx_queues[queue_idx]); diff --git a/drivers/net/intel/iavf/iavf_rxtx.c b/drivers/net/intel/iavf/iavf_rxtx.c index d8662fd815..a8d7c2fc1d 100644 --- a/drivers/net/intel/iavf/iavf_rxtx.c +++ b/drivers/net/intel/iavf/iavf_rxtx.c @@ -146,20 +146,6 @@ iavf_get_monitor_addr(void *rx_queue, struct rte_power_monitor_cond *pmc) return 0; } -static inline int -check_rx_thresh(uint16_t nb_desc, uint16_t thresh) -{ - /* The following constraints must be satisfied: - * thresh < rxq->nb_rx_desc - */ - if (thresh >= nb_desc) { - PMD_INIT_LOG(ERR, "rx_free_thresh (%u) must be less than %u", - thresh, nb_desc); - return -EINVAL; - } - return 0; -} - static inline int check_tx_thresh(uint16_t nb_desc, uint16_t tx_rs_thresh, uint16_t tx_free_thresh) @@ -589,8 +575,15 @@ iavf_dev_rx_queue_setup(struct rte_eth_dev *dev, uint16_t queue_idx, rx_free_thresh = (rx_conf->rx_free_thresh == 0) ? IAVF_DEFAULT_RX_FREE_THRESH : rx_conf->rx_free_thresh; - if (check_rx_thresh(nb_desc, rx_free_thresh) != 0) + /* Check that ring size is > 2 * rx_free_thresh */ + if (nb_desc <= 2 * rx_free_thresh) { + PMD_INIT_LOG(ERR, "rx ring size (%u) must be > 2 * rx_free_thresh (%u)", + nb_desc, rx_free_thresh); + if (nb_desc == IAVF_MIN_RING_DESC) + PMD_INIT_LOG(ERR, "To use the minimum ring size (%u), reduce rx_free_thresh to a lower value (recommended %u)", + IAVF_MIN_RING_DESC, IAVF_MIN_RING_DESC / 4); return -EINVAL; + } /* Free memory if needed */ if (dev->data->rx_queues[queue_idx]) { diff --git a/drivers/net/intel/ice/ice_rxtx.c b/drivers/net/intel/ice/ice_rxtx.c index 74db0fbec9..510eb1d316 100644 --- a/drivers/net/intel/ice/ice_rxtx.c +++ b/drivers/net/intel/ice/ice_rxtx.c @@ -1295,6 +1295,16 @@ ice_rx_queue_setup(struct rte_eth_dev *dev, return -EINVAL; } + /* Check that ring size is > 2 * rx_free_thresh */ + if (nb_desc <= 2 * rx_conf->rx_free_thresh) { + PMD_INIT_LOG(ERR, "rx ring size (%u) must be > 2 * rx_free_thresh (%u)", + nb_desc, rx_conf->rx_free_thresh); + if (nb_desc == ICE_MIN_RING_DESC) + PMD_INIT_LOG(ERR, "To use the minimum ring size (%u), reduce rx_free_thresh to a lower value (recommended %u)", + ICE_MIN_RING_DESC, ICE_MIN_RING_DESC / 4); + return -EINVAL; + } + offloads = rx_conf->offloads | dev->data->dev_conf.rxmode.offloads; if (mp) diff --git a/drivers/net/intel/idpf/idpf_rxtx.c b/drivers/net/intel/idpf/idpf_rxtx.c index 4796d8b862..fefe7d89ce 100644 --- a/drivers/net/intel/idpf/idpf_rxtx.c +++ b/drivers/net/intel/idpf/idpf_rxtx.c @@ -244,6 +244,16 @@ idpf_rx_queue_setup(struct rte_eth_dev *dev, uint16_t queue_idx, if (idpf_qc_rx_thresh_check(nb_desc, rx_free_thresh) != 0) return -EINVAL; + /* Check that ring size is > 2 * rx_free_thresh */ + if (nb_desc <= 2 * rx_free_thresh) { + PMD_INIT_LOG(ERR, "rx ring size (%u) must be > 2 * rx_free_thresh (%u)", + nb_desc, rx_free_thresh); + if (rx_free_thresh == IDPF_DEFAULT_RX_FREE_THRESH) + PMD_INIT_LOG(ERR, "To use ring sizes of %u or smaller, reduce rx_free_thresh", + IDPF_DEFAULT_RX_FREE_THRESH * 2); + return -EINVAL; + } + /* Free memory if needed */ if (dev->data->rx_queues[queue_idx] != NULL) { idpf_qc_rx_queue_release(dev->data->rx_queues[queue_idx]); diff --git a/drivers/net/intel/ixgbe/ixgbe_rxtx.c b/drivers/net/intel/ixgbe/ixgbe_rxtx.c index a7583c178a..9f36179c21 100644 --- a/drivers/net/intel/ixgbe/ixgbe_rxtx.c +++ b/drivers/net/intel/ixgbe/ixgbe_rxtx.c @@ -3206,6 +3206,16 @@ ixgbe_dev_rx_queue_setup(struct rte_eth_dev *dev, return -EINVAL; } + /* Check that ring size is > 2 * rx_free_thresh */ + if (nb_desc <= 2 * rx_conf->rx_free_thresh) { + PMD_INIT_LOG(ERR, "rx ring size (%u) must be > 2 * rx_free_thresh (%u)", + nb_desc, rx_conf->rx_free_thresh); + if (nb_desc == IXGBE_MIN_RING_DESC) + PMD_INIT_LOG(ERR, "To use the minimum ring size (%u), reduce rx_free_thresh to a lower value (recommended %u)", + IXGBE_MIN_RING_DESC, IXGBE_MIN_RING_DESC / 4); + return -EINVAL; + } + /* Free memory prior to re-allocation if needed... */ if (dev->data->rx_queues[queue_idx] != NULL) { ixgbe_rx_queue_release(dev->data->rx_queues[queue_idx]); -- 2.51.0