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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 84A07C4CECE for ; Mon, 14 Oct 2019 12:48:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 59E7420673 for ; Mon, 14 Oct 2019 12:48:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731206AbfJNMsv (ORCPT ); Mon, 14 Oct 2019 08:48:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44916 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731092AbfJNMsv (ORCPT ); Mon, 14 Oct 2019 08:48:51 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 63DD610C0938; Mon, 14 Oct 2019 12:48:50 +0000 (UTC) Received: from carbon (ovpn-200-46.brq.redhat.com [10.40.200.46]) by smtp.corp.redhat.com (Postfix) with ESMTP id 131E260920; Mon, 14 Oct 2019 12:48:39 +0000 (UTC) Date: Mon, 14 Oct 2019 14:48:38 +0200 From: Jesper Dangaard Brouer To: Lorenzo Bianconi Cc: netdev@vger.kernel.org, lorenzo.bianconi@redhat.com, davem@davemloft.net, thomas.petazzoni@bootlin.com, ilias.apalodimas@linaro.org, matteo.croce@redhat.com, mw@semihalf.com, brouer@redhat.com Subject: Re: [PATCH v3 net-next 5/8] net: mvneta: add basic XDP support Message-ID: <20191014144838.7a6e931b@carbon> In-Reply-To: <7c53ff9e148b80613088c7c35444244cbe1358bf.1571049326.git.lorenzo@kernel.org> References: <7c53ff9e148b80613088c7c35444244cbe1358bf.1571049326.git.lorenzo@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.66]); Mon, 14 Oct 2019 12:48:50 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, 14 Oct 2019 12:49:52 +0200 Lorenzo Bianconi wrote: > Add basic XDP support to mvneta driver for devices that rely on software > buffer management. Currently supported verdicts are: > - XDP_DROP > - XDP_PASS > - XDP_REDIRECT > - XDP_ABORTED > > - iptables drop: > $iptables -t raw -I PREROUTING -p udp --dport 9 -j DROP > $nstat -n && sleep 1 && nstat > IpInReceives 151169 0.0 > IpExtInOctets 6953544 0.0 > IpExtInNoECTPkts 151165 0.0 > > - XDP_DROP via xdp1 > $./samples/bpf/xdp1 3 > proto 0: 421419 pkt/s > proto 0: 421444 pkt/s > proto 0: 421393 pkt/s > proto 0: 421440 pkt/s > proto 0: 421184 pkt/s > > Tested-by: Matteo Croce > Signed-off-by: Lorenzo Bianconi > --- > drivers/net/ethernet/marvell/mvneta.c | 147 ++++++++++++++++++++++++-- > 1 file changed, 138 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > index 1722dffe265d..b47a44cf9610 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -38,6 +38,7 @@ > #include > #include > #include > +#include > > /* Registers */ > #define MVNETA_RXQ_CONFIG_REG(q) (0x1400 + ((q) << 2)) > @@ -323,8 +324,10 @@ > ETH_HLEN + ETH_FCS_LEN, \ > cache_line_size()) > > +#define MVNETA_SKB_HEADROOM (max(XDP_PACKET_HEADROOM, NET_SKB_PAD) + \ > + NET_IP_ALIGN) > #define MVNETA_SKB_PAD (SKB_DATA_ALIGN(sizeof(struct skb_shared_info) + \ > - NET_SKB_PAD)) > + MVNETA_SKB_HEADROOM)) > #define MVNETA_SKB_SIZE(len) (SKB_DATA_ALIGN(len) + MVNETA_SKB_PAD) > #define MVNETA_MAX_RX_BUF_SIZE (PAGE_SIZE - MVNETA_SKB_PAD) > > @@ -352,6 +355,11 @@ struct mvneta_statistic { > #define T_REG_64 64 > #define T_SW 1 > > +#define MVNETA_XDP_PASS BIT(0) > +#define MVNETA_XDP_CONSUMED BIT(1) I find it confusing that you call it "consumed" (MVNETA_XDP_CONSUMED), because if I follow the code these are all drop-cases that are due to errors. Can we call it MVNETA_XDP_DROPPED? I also checked, your XDP_TX patch[8/8], that all the return paths for MVNETA_XDP_CONSUMED also leads to drop of the xdp_buff. > +#define MVNETA_XDP_TX BIT(2) > +#define MVNETA_XDP_REDIR BIT(3) > + > static const struct mvneta_statistic mvneta_statistics[] = { > { 0x3000, T_REG_64, "good_octets_received", }, > { 0x3010, T_REG_32, "good_frames_received", }, > @@ -431,6 +439,8 @@ struct mvneta_port { > u32 cause_rx_tx; > struct napi_struct napi; > > + struct bpf_prog *xdp_prog; > + > /* Core clock */ > struct clk *clk; > /* AXI clock */ > @@ -1950,11 +1960,51 @@ int mvneta_rx_refill_queue(struct mvneta_port *pp, struct mvneta_rx_queue *rxq) > return i; > } > > +static int > +mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, > + struct bpf_prog *prog, struct xdp_buff *xdp) > +{ > + u32 ret, act = bpf_prog_run_xdp(prog, xdp); > + > + switch (act) { > + case XDP_PASS: > + ret = MVNETA_XDP_PASS; > + break; > + case XDP_REDIRECT: { > + int err; > + > + err = xdp_do_redirect(pp->dev, xdp, prog); > + if (err) { > + ret = MVNETA_XDP_CONSUMED; > + xdp_return_buff(xdp); Dropped in case of errors. As this is an error case, I don't mind that you use the slower xdp_return_buff(). > + } else { > + ret = MVNETA_XDP_REDIR; > + } > + break; > + } > + default: > + bpf_warn_invalid_xdp_action(act); > + /* fall through */ > + case XDP_ABORTED: > + trace_xdp_exception(pp->dev, prog, act); > + /* fall through */ > + case XDP_DROP: > + page_pool_recycle_direct(rxq->page_pool, > + virt_to_head_page(xdp->data)); > + ret = MVNETA_XDP_CONSUMED; Also drop case. > + break; > + } > + > + return ret; > +} > + > static int > mvneta_swbm_rx_frame(struct mvneta_port *pp, > struct mvneta_rx_desc *rx_desc, > struct mvneta_rx_queue *rxq, > - struct page *page) > + struct xdp_buff *xdp, > + struct bpf_prog *xdp_prog, > + struct page *page, u32 *xdp_ret) > { > unsigned char *data = page_address(page); > int data_len = -MVNETA_MH_SIZE, len; > @@ -1974,7 +2024,26 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp, > rx_desc->buf_phys_addr, > len, dma_dir); > > - rxq->skb = build_skb(data, PAGE_SIZE); > + xdp->data_hard_start = data; > + xdp->data = data + MVNETA_SKB_HEADROOM + MVNETA_MH_SIZE; > + xdp->data_end = xdp->data + data_len; > + xdp_set_data_meta_invalid(xdp); > + > + if (xdp_prog) { > + u32 ret; > + > + ret = mvneta_run_xdp(pp, rxq, xdp_prog, xdp); > + if (ret != MVNETA_XDP_PASS) { > + mvneta_update_stats(pp, 1, > + xdp->data_end - xdp->data, Good, you took into account that data_len cannot be used, as BPF/XDP program could have changed data pointer, thus affecting the length. > + false); > + rx_desc->buf_phys_addr = 0; > + *xdp_ret |= ret; > + return ret; > + } > + } > + > + rxq->skb = build_skb(xdp->data_hard_start, PAGE_SIZE); > if (unlikely(!rxq->skb)) { > netdev_err(dev, > "Can't allocate skb on queue %d\n", > @@ -1985,8 +2054,9 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp, > } > page_pool_release_page(rxq->page_pool, page); > > - skb_reserve(rxq->skb, MVNETA_MH_SIZE + NET_SKB_PAD); > - skb_put(rxq->skb, data_len); > + skb_reserve(rxq->skb, > + xdp->data - xdp->data_hard_start); > + skb_put(rxq->skb, xdp->data_end - xdp->data); > mvneta_rx_csum(pp, rx_desc->status, rxq->skb); > > rxq->left_size = rx_desc->data_size - len; > @@ -2020,7 +2090,7 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp, > /* refill descriptor with new buffer later */ > skb_add_rx_frag(rxq->skb, > skb_shinfo(rxq->skb)->nr_frags, > - page, NET_SKB_PAD, data_len, > + page, MVNETA_SKB_HEADROOM, data_len, > PAGE_SIZE); > } > page_pool_release_page(rxq->page_pool, page); > @@ -2035,10 +2105,17 @@ static int mvneta_rx_swbm(struct napi_struct *napi, > { > int rcvd_pkts = 0, rcvd_bytes = 0; > int rx_pending, refill, done = 0; > + struct bpf_prog *xdp_prog; > + struct xdp_buff xdp_buf; > + u32 xdp_ret = 0; > > /* Get number of received packets */ > rx_pending = mvneta_rxq_busy_desc_num_get(pp, rxq); > > + rcu_read_lock(); > + xdp_prog = READ_ONCE(pp->xdp_prog); > + xdp_buf.rxq = &rxq->xdp_rxq; Ok, thanks for following my review comments from last. > /* Fairness NAPI loop */ > while (done < budget && done < rx_pending) { > struct mvneta_rx_desc *rx_desc = mvneta_rxq_next_desc_get(rxq); > @@ -2066,7 +2143,8 @@ static int mvneta_rx_swbm(struct napi_struct *napi, > continue; > } > > - err = mvneta_swbm_rx_frame(pp, rx_desc, rxq, page); > + err = mvneta_swbm_rx_frame(pp, rx_desc, rxq, &xdp_buf, > + xdp_prog, page, &xdp_ret); > if (err) > continue; > } else { > @@ -2101,6 +2179,10 @@ static int mvneta_rx_swbm(struct napi_struct *napi, > /* clean uncomplete skb pointer in queue */ > rxq->skb = NULL; > } > + rcu_read_unlock(); > + > + if (xdp_ret & MVNETA_XDP_REDIR) > + xdp_do_flush_map(); > > mvneta_update_stats(pp, rcvd_pkts, rcvd_bytes, false); > [...] -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer