From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by dpdk.org (Postfix) with ESMTP id 089A71B1F7; Thu, 1 Nov 2018 14:13:25 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 01 Nov 2018 06:13:24 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,452,1534834800"; d="scan'208";a="85916701" Received: from fmsmsx106.amr.corp.intel.com ([10.18.124.204]) by orsmga007.jf.intel.com with ESMTP; 01 Nov 2018 06:13:24 -0700 Received: from shsmsx101.ccr.corp.intel.com (10.239.4.153) by FMSMSX106.amr.corp.intel.com (10.18.124.204) with Microsoft SMTP Server (TLS) id 14.3.408.0; Thu, 1 Nov 2018 06:13:23 -0700 Received: from shsmsx103.ccr.corp.intel.com ([169.254.4.161]) by SHSMSX101.ccr.corp.intel.com ([169.254.1.102]) with mapi id 14.03.0415.000; Thu, 1 Nov 2018 21:13:22 +0800 From: "Zhang, Qi Z" To: "Ananyev, Konstantin" , "Xing, Beilei" CC: "dev@dpdk.org" , "stable@dpdk.org" Thread-Topic: [dpdk-dev] [PATCH v3] net/i40e: fix Rx instability with vector mode Thread-Index: AQHUcacDIig8fVyAVkSLCSLJUcXTIaU6SBqAgACcoRA= Date: Thu, 1 Nov 2018 13:13:21 +0000 Message-ID: <039ED4275CED7440929022BC67E70611532DE52F@SHSMSX103.ccr.corp.intel.com> References: <1540535607-115720-1-git-send-email-beilei.xing@intel.com> <1541051597-28949-1-git-send-email-beilei.xing@intel.com> <2601191342CEEE43887BDE71AB9772580103067496@irsmsx105.ger.corp.intel.com> In-Reply-To: <2601191342CEEE43887BDE71AB9772580103067496@irsmsx105.ger.corp.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiODdhZTQxMjItN2JiMi00ODlkLThmNjQtYThiY2UyMGM0NzBlIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoidVc1XC9sZVZmUUNnNHArbTh0TjJ3dUpxanBKNUNPZ3dTTytQUlg2NDZSRzlPZ3hsZXZnU2hlNXVpK3VCd0J5dkEifQ== x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.0.400.15 dlp-reaction: no-action x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v3] 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: Thu, 01 Nov 2018 13:13:26 -0000 > -----Original Message----- > From: Ananyev, Konstantin > Sent: Thursday, November 1, 2018 6:48 AM > To: Xing, Beilei ; Zhang, Qi Z > Cc: dev@dpdk.org; stable@dpdk.org > Subject: RE: [dpdk-dev] [PATCH v3] net/i40e: fix Rx instability with vect= or > mode >=20 >=20 > Hi >=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. > > > > Fixes: 8e109464c022 ("i40e: allow vector Rx and Tx usage") > > Fixes: a3c83a2527e1 ("net/i40e: enable runtime queue setup") > > Cc: stable@dpdk.org > > > > Signed-off-by: Beilei Xing > > --- > > 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. > > > > doc/guides/nics/i40e.rst | 7 +++++++ > > drivers/net/i40e/i40e_rxtx.c | 30 +++++++++++++++++++++++++++--- > > 2 files changed, 34 insertions(+), 3 deletions(-) > > > > 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 > > > > -w 84:00.0,use-latest-supported-vec=3D1 > > > > +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 to the head after hitting the tail without a conditional > > +check. In addition Vector RX can use this assumption to do a bit mask > using ``ring_size - 1``. > > + > > Driver compilation and testing > > ------------------------------ > > > > diff --git a/drivers/net/i40e/i40e_rxtx.c > > b/drivers/net/i40e/i40e_rxtx.c index a827456..771193a 100644 > > --- a/drivers/net/i40e/i40e_rxtx.c > > +++ b/drivers/net/i40e/i40e_rxtx.c > > @@ -1735,12 +1735,21 @@ i40e_dev_rx_queue_setup_runtime(struct > rte_eth_dev *dev, > > * i40e_set_rx_function. > > */ > > ad->rx_bulk_alloc_allowed =3D true; > > - ad->rx_vec_allowed =3D true; > > dev->data->scattered_rx =3D use_scattered_rx; > > if (use_def_burst_func) > > ad->rx_bulk_alloc_allowed =3D false; > > + /** > > + * Vector mode is allowed only when number of Rx queue > > + * descriptor is a power of 2. > > + */ > > + ad->rx_vec_allowed =3D rte_is_power_of_2(rxq->nb_rx_desc); >=20 > Actually do we need to do it here? > We call set_rx_function() anyway, it would do that check for us, wouldn't= it? >=20 > > 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; > > } > > > > /* check bulk alloc conflict */ > > @@ -2948,11 +2957,26 @@ i40e_set_rx_function(struct rte_eth_dev *dev) > > { > > struct i40e_adapter *ad =3D > > I40E_DEV_PRIVATE_TO_ADAPTER(dev->data->dev_private); > > + struct i40e_rx_queue *rxq; > > uint16_t rx_using_sse, i; > > + uint16_t desc; >=20 > Please add empty line between var definitions and start of code. > Helps readability. >=20 > > /* In order to allow Vector Rx there are a few configuration > > * conditions to be met and Rx Bulk Allocation should be allowed. > > */ > > if (rte_eal_process_type() =3D=3D RTE_PROC_PRIMARY) { > > + if (!dev->data->dev_started) { > > + for (i =3D 0; i < dev->data->nb_rx_queues; i++) { > > + rxq =3D dev->data->rx_queues[i]; > > + desc =3D rxq->nb_rx_desc; > > + if (!i) queue_setup is not necessary start from queue 0, we can setup queue at any = order, so we can't assume i=3D0 is the first queue to setup. And also we need to check if (dev->data->rx_queues[i] =3D=3D NULL) to avoid= segment fault, since some queue may never be setup yet. > > + ad->rx_vec_allowed =3D > > + rte_is_power_of_2(desc); > > + else if (ad->rx_vec_allowed && > > + !rte_is_power_of_2(desc)) > > + ad->rx_vec_allowed =3D false; >=20 > Wouldn't be a bit cleaner: > ad->rx_vec_allowed =3D (ad->rx_vec_allowed =3D=3D true) ? > ad->rte_is_power_of_2(desc)) : ad->rx_vec_allowed; >=20 > > + } > > + } > > + >=20 > Probably better to move that code into > i40e_rx_vec_dev_conf_condition_check() > that will be called on next line? >=20 > > if (i40e_rx_vec_dev_conf_condition_check(dev) || > > !ad->rx_bulk_alloc_allowed) { > > PMD_INIT_LOG(DEBUG, "Port[%d] doesn't meet" > > @@ -2961,10 +2985,10 @@ i40e_set_rx_function(struct rte_eth_dev *dev) > > > > ad->rx_vec_allowed =3D false; > > } > > + > > if (ad->rx_vec_allowed) { > > for (i =3D 0; i < dev->data->nb_rx_queues; i++) { > > - struct i40e_rx_queue *rxq =3D > > - dev->data->rx_queues[i]; > > + rxq =3D dev->data->rx_queues[i]; > > > > if (rxq && i40e_rxq_vec_setup(rxq)) { > > ad->rx_vec_allowed =3D false; > > -- > > 2.5.5