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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 D02D4C3F2D2 for ; Mon, 2 Mar 2020 14:13:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A528B21D56 for ; Mon, 2 Mar 2020 14:13:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583158399; bh=Cq3mXNnU6SEGy1QJQk3Nc9ESdUKuq8VZoXOzmjrlv9Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=dsSin/F6TfbJGvLx9qQPwOgN25hBwtomK0vnrb9Ia7N14/9//IO7swS69qpfMZyV8 KSmmBrmBk3Fm0zHJUs3xQ/uBHEByXCzM2DFOnItTMHyMQeCChrgyLapywXTQvBjygz ozwyPSP7vmCc4+lf292VMzBUkVt6SiCkfEkfCE3c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727101AbgCBONS (ORCPT ); Mon, 2 Mar 2020 09:13:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:38848 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726884AbgCBONS (ORCPT ); Mon, 2 Mar 2020 09:13:18 -0500 Received: from lore-desk-wlan (unknown [151.48.128.122]) (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 09F4B2080C; Mon, 2 Mar 2020 14:13:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583158397; bh=Cq3mXNnU6SEGy1QJQk3Nc9ESdUKuq8VZoXOzmjrlv9Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=UpvzpEnRCJ829cLNBLvziNlpjTzWI+LlB2hzq1xXpbV/CHajih58v3T2HpYuWH38Q ExaSR6K7dj/yq4bbwzsq2b3cWGvqRPpKbVO+lAbZ4Brlqt7VPhgcFDWoGdRlv9yeoG LIfSlAFC6u47RNzcQGnhoLTqCGzQWFX4bTe2hTkw= Date: Mon, 2 Mar 2020 15:13:05 +0100 From: Lorenzo Bianconi To: Jesper Dangaard Brouer Cc: netdev@vger.kernel.org, "David S. Miller" , Ilias Apalodimas , David Ahern , Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= , Saeed Mahameed , Tariq Toukan , kuba@kernel.org, andrew@lunn.ch, thomas.petazzoni@bootlin.com Subject: Re: [net-next PATCH] mvneta: add XDP ethtool errors stats for TX to driver Message-ID: <20200302141305.GD1391852@lore-desk-wlan> References: <158315678810.1983667.11239367181663328821.stgit@firesoul> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="zS7rBR6csb6tI2e1" Content-Disposition: inline In-Reply-To: <158315678810.1983667.11239367181663328821.stgit@firesoul> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --zS7rBR6csb6tI2e1 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > Adding ethtool stats for when XDP transmitted packets overrun the TX > queue. This is recorded separately for XDP_TX and ndo_xdp_xmit. This > is an important aid for troubleshooting XDP based setups. >=20 > It is currently a known weakness and property of XDP that there isn't > any push-back or congestion feedback when transmitting frames via XDP. > It's easy to realise when redirecting from a higher speed link into a > slower speed link, or simply two ingress links into a single egress. > The situation can also happen when Ethernet flow control is active. >=20 > For testing the patch and provoking the situation to occur on my > Espressobin board, I configured the TX-queue to be smaller (434) than > RX-queue (512) and overload network with large MTU size frames (as a > larger frame takes longer to transmit). >=20 > Hopefully the upcoming XDP TX hook can be extended to provide insight > into these TX queue overflows, to allow programmable adaptation > strategies. >=20 > Signed-off-by: Jesper Dangaard Brouer This was on my ToDo list, thx for working on this :) Acked-by: Lorenzo Bianconi > --- > drivers/net/ethernet/marvell/mvneta.c | 30 ++++++++++++++++++++++++++-= --- > 1 file changed, 26 insertions(+), 4 deletions(-) >=20 > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet= /marvell/mvneta.c > index b22eeb5f8700..bc488e8b8e45 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -344,8 +344,10 @@ enum { > ETHTOOL_XDP_REDIRECT, > ETHTOOL_XDP_PASS, > ETHTOOL_XDP_DROP, > - ETHTOOL_XDP_XMIT, > ETHTOOL_XDP_TX, > + ETHTOOL_XDP_TX_ERR, > + ETHTOOL_XDP_XMIT, > + ETHTOOL_XDP_XMIT_ERR, > ETHTOOL_MAX_STATS, > }; > =20 > @@ -404,7 +406,9 @@ static const struct mvneta_statistic mvneta_statistic= s[] =3D { > { ETHTOOL_XDP_PASS, T_SW, "rx_xdp_pass", }, > { ETHTOOL_XDP_DROP, T_SW, "rx_xdp_drop", }, > { ETHTOOL_XDP_TX, T_SW, "rx_xdp_tx", }, > + { ETHTOOL_XDP_TX_ERR, T_SW, "rx_xdp_tx_errors", }, > { ETHTOOL_XDP_XMIT, T_SW, "tx_xdp_xmit", }, > + { ETHTOOL_XDP_XMIT_ERR, T_SW, "tx_xdp_xmit_errors", }, > }; > =20 > struct mvneta_stats { > @@ -417,7 +421,9 @@ struct mvneta_stats { > u64 xdp_pass; > u64 xdp_drop; > u64 xdp_xmit; > + u64 xdp_xmit_err; > u64 xdp_tx; > + u64 xdp_tx_err; > }; > =20 > struct mvneta_ethtool_stats { > @@ -2059,6 +2065,7 @@ mvneta_xdp_submit_frame(struct mvneta_port *pp, str= uct mvneta_tx_queue *txq, > static int > mvneta_xdp_xmit_back(struct mvneta_port *pp, struct xdp_buff *xdp) > { > + struct mvneta_pcpu_stats *stats =3D this_cpu_ptr(pp->stats); > struct mvneta_tx_queue *txq; > struct netdev_queue *nq; > struct xdp_frame *xdpf; > @@ -2076,8 +2083,6 @@ mvneta_xdp_xmit_back(struct mvneta_port *pp, struct= xdp_buff *xdp) > __netif_tx_lock(nq, cpu); > ret =3D mvneta_xdp_submit_frame(pp, txq, xdpf, false); > if (ret =3D=3D MVNETA_XDP_TX) { > - struct mvneta_pcpu_stats *stats =3D this_cpu_ptr(pp->stats); > - > u64_stats_update_begin(&stats->syncp); > stats->es.ps.tx_bytes +=3D xdpf->len; > stats->es.ps.tx_packets++; > @@ -2085,6 +2090,10 @@ mvneta_xdp_xmit_back(struct mvneta_port *pp, struc= t xdp_buff *xdp) > u64_stats_update_end(&stats->syncp); > =20 > mvneta_txq_pend_desc_add(pp, txq, 0); > + } else { > + u64_stats_update_begin(&stats->syncp); > + stats->es.ps.xdp_tx_err++; > + u64_stats_update_end(&stats->syncp); > } > __netif_tx_unlock(nq); > =20 > @@ -2128,6 +2137,7 @@ mvneta_xdp_xmit(struct net_device *dev, int num_fra= me, > stats->es.ps.tx_bytes +=3D nxmit_byte; > stats->es.ps.tx_packets +=3D nxmit; > stats->es.ps.xdp_xmit +=3D nxmit; > + stats->es.ps.xdp_xmit_err +=3D num_frame - nxmit; > u64_stats_update_end(&stats->syncp); > =20 > return nxmit; > @@ -2152,7 +2162,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvnet= a_rx_queue *rxq, > int err; > =20 > err =3D xdp_do_redirect(pp->dev, xdp, prog); > - if (err) { > + if (unlikely(err)) { > ret =3D MVNETA_XDP_DROPPED; > page_pool_put_page(rxq->page_pool, > virt_to_head_page(xdp->data), len, > @@ -4518,6 +4528,8 @@ mvneta_ethtool_update_pcpu_stats(struct mvneta_port= *pp, > u64 skb_alloc_error; > u64 refill_error; > u64 xdp_redirect; > + u64 xdp_xmit_err; > + u64 xdp_tx_err; > u64 xdp_pass; > u64 xdp_drop; > u64 xdp_xmit; > @@ -4532,7 +4544,9 @@ mvneta_ethtool_update_pcpu_stats(struct mvneta_port= *pp, > xdp_pass =3D stats->es.ps.xdp_pass; > xdp_drop =3D stats->es.ps.xdp_drop; > xdp_xmit =3D stats->es.ps.xdp_xmit; > + xdp_xmit_err =3D stats->es.ps.xdp_xmit_err; > xdp_tx =3D stats->es.ps.xdp_tx; > + xdp_tx_err =3D stats->es.ps.xdp_tx_err; > } while (u64_stats_fetch_retry_irq(&stats->syncp, start)); > =20 > es->skb_alloc_error +=3D skb_alloc_error; > @@ -4541,7 +4555,9 @@ mvneta_ethtool_update_pcpu_stats(struct mvneta_port= *pp, > es->ps.xdp_pass +=3D xdp_pass; > es->ps.xdp_drop +=3D xdp_drop; > es->ps.xdp_xmit +=3D xdp_xmit; > + es->ps.xdp_xmit_err +=3D xdp_xmit_err; > es->ps.xdp_tx +=3D xdp_tx; > + es->ps.xdp_tx_err +=3D xdp_tx_err; > } > } > =20 > @@ -4594,9 +4610,15 @@ static void mvneta_ethtool_update_stats(struct mvn= eta_port *pp) > case ETHTOOL_XDP_TX: > pp->ethtool_stats[i] =3D stats.ps.xdp_tx; > break; > + case ETHTOOL_XDP_TX_ERR: > + pp->ethtool_stats[i] =3D stats.ps.xdp_tx_err; > + break; > case ETHTOOL_XDP_XMIT: > pp->ethtool_stats[i] =3D stats.ps.xdp_xmit; > break; > + case ETHTOOL_XDP_XMIT_ERR: > + pp->ethtool_stats[i] =3D stats.ps.xdp_xmit_err; > + break; > } > break; > } >=20 >=20 --zS7rBR6csb6tI2e1 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTquNwa3Txd3rGGn7Y6cBh0uS2trAUCXl0UbwAKCRA6cBh0uS2t rMqcAQCNMJegf9ZLWFR9rbkHEFXRcx0j+fXBPOVB2aasN420BAD9F3jcqF+VRs8M 0dnQ/LPkxJSsOR2w2lcN7/cngwR+NAc= =RQ+r -----END PGP SIGNATURE----- --zS7rBR6csb6tI2e1--