From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lucas Stach Subject: Re: [PATCH] net: fec: only clear a queue's work bit if the queue was emptied Date: Tue, 03 May 2016 16:42:46 +0200 Message-ID: <1462286566.17746.1.camel@pengutronix.de> References: <1462286333-23402-1-git-send-email-u.kleine-koenig@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Fugang Duan , "David S . Miller" , netdev@vger.kernel.org, kernel@pengutronix.de To: Uwe =?ISO-8859-1?Q?Kleine-K=F6nig?= Return-path: Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:56483 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932545AbcECOmu (ORCPT ); Tue, 3 May 2016 10:42:50 -0400 In-Reply-To: <1462286333-23402-1-git-send-email-u.kleine-koenig@pengutronix.de> Sender: netdev-owner@vger.kernel.org List-ID: Am Dienstag, den 03.05.2016, 16:38 +0200 schrieb Uwe Kleine-K=C3=B6nig: > In the receive path a queue's work bit was cleared unconditionally ev= en > if fec_enet_rx_queue only read out a part of the available packets fr= om > the hardware. This resulted in not reading any packets in the next na= pi > turn and so packets were delayed or lost. >=20 > The obvious fix is to only clear a queue's bit when the queue was > emptied. >=20 > Fixes: 4d494cdc92b3 ("net: fec: change data structure to support mult= iqueue") > Signed-off-by: Uwe Kleine-K=C3=B6nig Reviewed-by: Lucas Stach > --- > Hello, >=20 > I created this patch against net/master. If you think it's to late to > get it into 4.6 and it doesn't fit on net-next/master, just tell me a= nd > I will rebase. >=20 > Best regards > Uwe >=20 >=20 > drivers/net/ethernet/freescale/fec_main.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) >=20 > diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/= ethernet/freescale/fec_main.c > index 08243c2ff4b4..2a03857cca18 100644 > --- a/drivers/net/ethernet/freescale/fec_main.c > +++ b/drivers/net/ethernet/freescale/fec_main.c > @@ -1521,9 +1521,15 @@ fec_enet_rx(struct net_device *ndev, int budge= t) > struct fec_enet_private *fep =3D netdev_priv(ndev); > =20 > for_each_set_bit(queue_id, &fep->work_rx, FEC_ENET_MAX_RX_QS) { > - clear_bit(queue_id, &fep->work_rx); > - pkt_received +=3D fec_enet_rx_queue(ndev, > + int ret; > + > + ret =3D fec_enet_rx_queue(ndev, > budget - pkt_received, queue_id); > + > + if (ret < budget - pkt_received) > + clear_bit(queue_id, &fep->work_rx); > + > + pkt_received +=3D ret; > } > return pkt_received; > }