Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757439AbcLALoR (ORCPT ); Thu, 1 Dec 2016 06:44:17 -0500 Received: from mx0b-0016f401.pphosted.com ([67.231.156.173]:40815 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751140AbcLALn6 (ORCPT ); Thu, 1 Dec 2016 06:43:58 -0500 Date: Thu, 1 Dec 2016 19:38:10 +0800 From: Jisheng Zhang To: Gregory CLEMENT CC: "David S. Miller" , , , Arnd Bergmann , Jason Cooper , Andrew Lunn , "Sebastian Hesselbarth" , Thomas Petazzoni , , Nadav Haklai , Marcin Wojtas , Dmitri Epshtein , Yelena Krivosheev Subject: Re: [PATCH v5 net-next 3/7] net: mvneta: Use cacheable memory to store the rx buffer virtual address Message-ID: <20161201193810.3192310f@xhacker> In-Reply-To: <2e54b7711de0b971a7a9ee3662dad02d12bec385.1480542157.git-series.gregory.clement@free-electrons.com> References: <2e54b7711de0b971a7a9ee3662dad02d12bec385.1480542157.git-series.gregory.clement@free-electrons.com> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-12-01_07:,, signatures=0 X-Proofpoint-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1609300000 definitions=main-1612010205 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5116 Lines: 138 On Wed, 30 Nov 2016 22:42:48 +0100 Gregory CLEMENT wrote: > Until now the virtual address of the received buffer were stored in the > cookie field of the rx descriptor. However, this field is 32-bits only > which prevents to use the driver on a 64-bits architecture. > > With this patch the virtual address is stored in an array not shared with > the hardware (no more need to use the DMA API). Thanks to this, it is > possible to use cache contrary to the access of the rx descriptor member. > > The change is done in the swbm path only because the hwbm uses the cookie > field, this also means that currently the hwbm is not usable in 64-bits. > > Signed-off-by: Gregory CLEMENT Reviewed-by: Jisheng Zhang Thanks, Jisheng > --- > drivers/net/ethernet/marvell/mvneta.c | 34 +++++++++++++++++++--------- > 1 file changed, 24 insertions(+), 10 deletions(-) > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > index f5319c50f8d9..92b9af14c352 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -561,6 +561,9 @@ struct mvneta_rx_queue { > u32 pkts_coal; > u32 time_coal; > > + /* Virtual address of the RX buffer */ > + void **buf_virt_addr; > + > /* Virtual address of the RX DMA descriptors array */ > struct mvneta_rx_desc *descs; > > @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, > > /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ > static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, > - u32 phys_addr, u32 cookie) > + u32 phys_addr, void *virt_addr, > + struct mvneta_rx_queue *rxq) > { > - rx_desc->buf_cookie = cookie; > + int i; > + > rx_desc->buf_phys_addr = phys_addr; > + i = rx_desc - rxq->descs; > + rxq->buf_virt_addr[i] = virt_addr; > } > > /* Decrement sent descriptors counter */ > @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); > > /* Refill processing for SW buffer management */ > static int mvneta_rx_refill(struct mvneta_port *pp, > - struct mvneta_rx_desc *rx_desc) > + struct mvneta_rx_desc *rx_desc, > + struct mvneta_rx_queue *rxq) > > { > dma_addr_t phys_addr; > @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, > return -ENOMEM; > } > > - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); > + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); > return 0; > } > > @@ -1861,7 +1869,7 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, > > for (i = 0; i < rxq->size; i++) { > struct mvneta_rx_desc *rx_desc = rxq->descs + i; > - void *data = (void *)rx_desc->buf_cookie; > + void *data = rxq->buf_virt_addr[i]; > > dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr, > MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE); > @@ -1894,12 +1902,13 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, > unsigned char *data; > dma_addr_t phys_addr; > u32 rx_status, frag_size; > - int rx_bytes, err; > + int rx_bytes, err, index; > > rx_done++; > rx_status = rx_desc->status; > rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); > - data = (unsigned char *)rx_desc->buf_cookie; > + index = rx_desc - rxq->descs; > + data = rxq->buf_virt_addr[index]; > phys_addr = rx_desc->buf_phys_addr; > > if (!mvneta_rxq_desc_is_first_last(rx_status) || > @@ -1938,7 +1947,7 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, > } > > /* Refill processing */ > - err = mvneta_rx_refill(pp, rx_desc); > + err = mvneta_rx_refill(pp, rx_desc, rxq); > if (err) { > netdev_err(dev, "Linux processing - Can't refill\n"); > rxq->missed++; > @@ -2020,7 +2029,7 @@ static int mvneta_rx_hwbm(struct mvneta_port *pp, int rx_todo, > rx_done++; > rx_status = rx_desc->status; > rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); > - data = (unsigned char *)rx_desc->buf_cookie; > + data = (u8 *)(uintptr_t)rx_desc->buf_cookie; > phys_addr = rx_desc->buf_phys_addr; > pool_id = MVNETA_RX_GET_BM_POOL_ID(rx_desc); > bm_pool = &pp->bm_priv->bm_pools[pool_id]; > @@ -2716,7 +2725,7 @@ static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, > > for (i = 0; i < num; i++) { > memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc)); > - if (mvneta_rx_refill(pp, rxq->descs + i) != 0) { > + if (mvneta_rx_refill(pp, rxq->descs + i, rxq) != 0) { > netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs filled\n", > __func__, rxq->id, i, num); > break; > @@ -3865,6 +3874,11 @@ static int mvneta_init(struct device *dev, struct mvneta_port *pp) > rxq->size = pp->rx_ring_size; > rxq->pkts_coal = MVNETA_RX_COAL_PKTS; > rxq->time_coal = MVNETA_RX_COAL_USEC; > + rxq->buf_virt_addr = devm_kmalloc(pp->dev->dev.parent, > + rxq->size * sizeof(void *), > + GFP_KERNEL); > + if (!rxq->buf_virt_addr) > + return -ENOMEM; > } > > return 0;