From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by dpdk.org (Postfix) with ESMTP id 4B0A43238; Mon, 5 Nov 2018 12:05:05 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Nov 2018 03:05:04 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,467,1534834800"; d="scan'208";a="105996370" Received: from irsmsx154.ger.corp.intel.com ([163.33.192.96]) by orsmga002.jf.intel.com with ESMTP; 05 Nov 2018 03:05:03 -0800 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.144]) by IRSMSX154.ger.corp.intel.com ([169.254.12.166]) with mapi id 14.03.0415.000; Mon, 5 Nov 2018 11:05:02 +0000 From: "Ananyev, Konstantin" To: "Xing, Beilei" , "Zhang, Qi Z" CC: "dev@dpdk.org" , "stable@dpdk.org" Thread-Topic: [PATCH v4] net/i40e: fix Rx instability with vector mode Thread-Index: AQHUdLYPgAAjfor56kWrwq2QA7W8UqVBBSJQ Date: Mon, 5 Nov 2018 11:05:01 +0000 Message-ID: <2601191342CEEE43887BDE71AB9772580103068AF1@irsmsx105.ger.corp.intel.com> References: <1541051597-28949-1-git-send-email-beilei.xing@intel.com> <1541387892-51117-1-git-send-email-beilei.xing@intel.com> In-Reply-To: <1541387892-51117-1-git-send-email-beilei.xing@intel.com> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNWM5ZWUyNDUtMzhhNy00MTk1LTk2ZDctODU1NjM3MzFkZmVkIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoielRMN2I2XC9DcWNVdnRsVVdVMm5KQmc3a3hlMFBISDZzVzhRSnJMdE1VVGhsSkpOU2RJR2xcL0NFMlVOSU1HYlF3In0= x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.0.400.15 dlp-reaction: no-action x-originating-ip: [163.33.239.180] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v4] net/i40e: fix Rx instability with vector mode X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 05 Nov 2018 11:05:06 -0000 >=20 > Previously, there is instability during vector Rx if descriptor > number is not power of 2, e.g. process hang and some Rx packets > are unexpectedly empty. That's because vector Rx mode assumes Rx > descriptor number is power of 2 when doing bit mask. > This patch allows vector mode only when the number of Rx descriptor > is power of 2. >=20 > Fixes: 8e109464c022 ("i40e: allow vector Rx and Tx usage") > Fixes: a3c83a2527e1 ("net/i40e: enable runtime queue setup") > Cc: stable@dpdk.org >=20 > Signed-off-by: Beilei Xing > --- > v4 changes: > - Configure rx_vec_allowed in i40e_rx_vec_dev_conf_condition_check funct= ion. > v3 changes: > - Add branch for non-first queue during runtime queue setup. > - Use function rte_is_power_of_2(). > - Configure rx_vec_allowed during setting Rx function. > v2 changes: > - rx_vec_allowed is global configuration, avoid overwrite. >=20 > doc/guides/nics/i40e.rst | 7 ++++++ > drivers/net/i40e/i40e_rxtx.c | 5 +++++ > drivers/net/i40e/i40e_rxtx_vec_common.h | 38 +++++++++++++++++++++++++++= ++++++ > 3 files changed, 50 insertions(+) >=20 > diff --git a/doc/guides/nics/i40e.rst b/doc/guides/nics/i40e.rst > index ab3928a..bfacbd1 100644 > --- a/doc/guides/nics/i40e.rst > +++ b/doc/guides/nics/i40e.rst > @@ -172,6 +172,13 @@ Runtime Config Options >=20 > -w 84:00.0,use-latest-supported-vec=3D1 >=20 > +Vector RX Pre-conditions > +~~~~~~~~~~~~~~~~~~~~~~~~ > +For Vector RX it is assumed that the number of descriptor rings will be = a power > +of 2. With this pre-condition, the ring pointer can easily scroll back t= o the > +head after hitting the tail without a conditional check. In addition Vec= tor RX > +can use this assumption to do a bit mask using ``ring_size - 1``. > + > Driver compilation and testing > ------------------------------ >=20 > diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c > index a827456..5bb1a3c 100644 > --- a/drivers/net/i40e/i40e_rxtx.c > +++ b/drivers/net/i40e/i40e_rxtx.c > @@ -1741,6 +1741,11 @@ i40e_dev_rx_queue_setup_runtime(struct rte_eth_dev= *dev, > ad->rx_bulk_alloc_allowed =3D false; > i40e_set_rx_function(dev); > return 0; > + } else if (ad->rx_vec_allowed && !rte_is_power_of_2(rxq->nb_rx_desc)) { > + PMD_DRV_LOG(ERR, "Vector mode is allowed, but descriptor" > + " number %d of queue %d isn't power of 2", > + rxq->nb_rx_desc, rxq->queue_id); > + return -EINVAL; > } >=20 > /* check bulk alloc conflict */ > diff --git a/drivers/net/i40e/i40e_rxtx_vec_common.h b/drivers/net/i40e/i= 40e_rxtx_vec_common.h > index f00f6d6..0e6ffa0 100644 > --- a/drivers/net/i40e/i40e_rxtx_vec_common.h > +++ b/drivers/net/i40e/i40e_rxtx_vec_common.h > @@ -192,8 +192,13 @@ static inline int > i40e_rx_vec_dev_conf_condition_check_default(struct rte_eth_dev *dev) > { > #ifndef RTE_LIBRTE_IEEE1588 > + struct i40e_adapter *ad =3D > + I40E_DEV_PRIVATE_TO_ADAPTER(dev->data->dev_private); > struct rte_eth_rxmode *rxmode =3D &dev->data->dev_conf.rxmode; > struct rte_fdir_conf *fconf =3D &dev->data->dev_conf.fdir_conf; > + struct i40e_rx_queue *rxq; > + uint16_t desc, i; > + bool first_queue; >=20 > /* no fdir support */ > if (fconf->mode !=3D RTE_FDIR_MODE_NONE) > @@ -207,6 +212,39 @@ i40e_rx_vec_dev_conf_condition_check_default(struct = rte_eth_dev *dev) > if (rxmode->offloads & DEV_RX_OFFLOAD_VLAN_EXTEND) > return -1; >=20 > + /** > + * Vector mode is allowed only when number of Rx queue > + * descriptor is power of 2. > + */ > + if (!dev->data->dev_started) { > + first_queue =3D true; > + for (i =3D 0; i < dev->data->nb_rx_queues; i++) { > + rxq =3D dev->data->rx_queues[i]; > + if (!rxq) > + continue; > + desc =3D rxq->nb_rx_desc; > + if (first_queue) > + ad->rx_vec_allowed =3D > + rte_is_power_of_2(desc); > + else > + ad->rx_vec_allowed =3D > + ad->rx_vec_allowed ? > + rte_is_power_of_2(desc) : > + ad->rx_vec_allowed; > + first_queue =3D false; > + } > + } else { > + /* Only check the first queue's descriptor number */ > + for (i =3D 0; i < dev->data->nb_rx_queues; i++) { > + rxq =3D dev->data->rx_queues[i]; > + if (!rxq) > + continue; > + desc =3D rxq->nb_rx_desc; > + ad->rx_vec_allowed =3D rte_is_power_of_2(desc); > + break; > + } > + } > + > return 0; > #else > RTE_SET_USED(dev); > -- Acked-by: Konstantin Ananyev > 2.5.5