From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3ACAD1850; Mon, 23 Oct 2023 06:57:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from out30-97.freemail.mail.aliyun.com (out30-97.freemail.mail.aliyun.com [115.124.30.97]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 81C63F7; Sun, 22 Oct 2023 23:57:52 -0700 (PDT) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R111e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045192;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0VufF4U5_1698044269; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VufF4U5_1698044269) by smtp.aliyun-inc.com; Mon, 23 Oct 2023 14:57:50 +0800 Message-ID: <1698044212.9541101-5-xuanzhuo@linux.alibaba.com> Subject: Re: [PATCH net-next v1 15/19] virtio_net: xsk: rx: introduce add_recvbuf_xsk() Date: Mon, 23 Oct 2023 14:56:52 +0800 From: Xuan Zhuo To: Jason Wang Cc: netdev@vger.kernel.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , virtualization@lists.linux-foundation.org, bpf@vger.kernel.org References: <20231016120033.26933-1-xuanzhuo@linux.alibaba.com> <20231016120033.26933-16-xuanzhuo@linux.alibaba.com> In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: On Fri, 20 Oct 2023 14:56:51 +0800, Jason Wang wrote: > On Mon, Oct 16, 2023 at 8:01=E2=80=AFPM Xuan Zhuo wrote: > > > > Implement the logic of filling vq with XSK buffer. > > > > Signed-off-by: Xuan Zhuo > > --- > > drivers/net/virtio/main.c | 13 +++++++ > > drivers/net/virtio/virtio_net.h | 5 +++ > > drivers/net/virtio/xsk.c | 66 ++++++++++++++++++++++++++++++++- > > drivers/net/virtio/xsk.h | 2 + > > 4 files changed, 85 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c > > index 58bb38f9b453..0e740447b142 100644 > > --- a/drivers/net/virtio/main.c > > +++ b/drivers/net/virtio/main.c > > @@ -1787,9 +1787,20 @@ static int add_recvbuf_mergeable(struct virtnet_= info *vi, > > static bool try_fill_recv(struct virtnet_info *vi, struct virtnet_rq *= rq, > > gfp_t gfp) > > { > > + struct xsk_buff_pool *pool; > > int err; > > bool oom; > > > > + rcu_read_lock(); > > A question here: should we sync with refill work during rx_pause? > > > + pool =3D rcu_dereference(rq->xsk.pool); > > + if (pool) { > > + err =3D virtnet_add_recvbuf_xsk(vi, rq, pool, gfp); > > + oom =3D err =3D=3D -ENOMEM; > > + rcu_read_unlock(); > > + goto kick; > > + } > > + rcu_read_unlock(); > > And if we synchronize with that there's probably no need for the rcu > and we can merge the logic with the following ones? YES. we synchronize the rx_pause and this. But for the rcu object, I think we should use rcu_xxx() API. Thanks. > > Thanks > > > > + > > do { > > if (vi->mergeable_rx_bufs) > > err =3D add_recvbuf_mergeable(vi, rq, gfp); > > @@ -1802,6 +1813,8 @@ static bool try_fill_recv(struct virtnet_info *vi= , struct virtnet_rq *rq, > > if (err) > > break; > > } while (rq->vq->num_free); > > + > > +kick: > > if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq))= { > > unsigned long flags; > > > > diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virti= o_net.h > > index d4e620a084f4..6e71622fca45 100644 > > --- a/drivers/net/virtio/virtio_net.h > > +++ b/drivers/net/virtio/virtio_net.h > > @@ -156,6 +156,11 @@ struct virtnet_rq { > > > > /* xdp rxq used by xsk */ > > struct xdp_rxq_info xdp_rxq; > > + > > + struct xdp_buff **xsk_buffs; > > + u32 nxt_idx; > > + u32 num; > > + u32 size; > > } xsk; > > }; > > > > diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c > > index 973e783260c3..841fb078882a 100644 > > --- a/drivers/net/virtio/xsk.c > > +++ b/drivers/net/virtio/xsk.c > > @@ -37,6 +37,58 @@ static void virtnet_xsk_check_queue(struct virtnet_s= q *sq) > > netif_stop_subqueue(dev, qnum); > > } > > > > +static int virtnet_add_recvbuf_batch(struct virtnet_info *vi, struct v= irtnet_rq *rq, > > + struct xsk_buff_pool *pool, gfp_t = gfp) > > +{ > > + struct xdp_buff **xsk_buffs; > > + dma_addr_t addr; > > + u32 len, i; > > + int err =3D 0; > > + > > + xsk_buffs =3D rq->xsk.xsk_buffs; > > + > > + if (rq->xsk.nxt_idx >=3D rq->xsk.num) { > > + rq->xsk.num =3D xsk_buff_alloc_batch(pool, xsk_buffs, r= q->xsk.size); > > + if (!rq->xsk.num) > > + return -ENOMEM; > > + rq->xsk.nxt_idx =3D 0; > > + } > > + > > + while (rq->xsk.nxt_idx < rq->xsk.num) { > > + i =3D rq->xsk.nxt_idx; > > + > > + /* use the part of XDP_PACKET_HEADROOM as the virtnet h= dr space */ > > + addr =3D xsk_buff_xdp_get_dma(xsk_buffs[i]) - vi->hdr_l= en; > > + len =3D xsk_pool_get_rx_frame_size(pool) + vi->hdr_len; > > + > > + sg_init_table(rq->sg, 1); > > + sg_fill_dma(rq->sg, addr, len); > > + > > + err =3D virtqueue_add_inbuf(rq->vq, rq->sg, 1, xsk_buff= s[i], gfp); > > + if (err) > > + return err; > > + > > + rq->xsk.nxt_idx++; > > + } > > + > > + return 0; > > +} > > + > > +int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct virtnet_rq= *rq, > > + struct xsk_buff_pool *pool, gfp_t gfp) > > +{ > > + int err; > > + > > + do { > > + err =3D virtnet_add_recvbuf_batch(vi, rq, pool, gfp); > > + if (err) > > + return err; > > + > > + } while (rq->vq->num_free); > > + > > + return 0; > > +} > > + > > static int virtnet_xsk_xmit_one(struct virtnet_sq *sq, > > struct xsk_buff_pool *pool, > > struct xdp_desc *desc) > > @@ -244,7 +296,7 @@ static int virtnet_xsk_pool_enable(struct net_devic= e *dev, > > struct virtnet_sq *sq; > > struct device *dma_dev; > > dma_addr_t hdr_dma; > > - int err; > > + int err, size; > > > > /* In big_packets mode, xdp cannot work, so there is no need to > > * initialize xsk of rq. > > @@ -276,6 +328,16 @@ static int virtnet_xsk_pool_enable(struct net_devi= ce *dev, > > if (!dma_dev) > > return -EPERM; > > > > + size =3D virtqueue_get_vring_size(rq->vq); > > + > > + rq->xsk.xsk_buffs =3D kcalloc(size, sizeof(*rq->xsk.xsk_buffs),= GFP_KERNEL); > > + if (!rq->xsk.xsk_buffs) > > + return -ENOMEM; > > + > > + rq->xsk.size =3D size; > > + rq->xsk.nxt_idx =3D 0; > > + rq->xsk.num =3D 0; > > + > > hdr_dma =3D dma_map_single(dma_dev, &xsk_hdr, vi->hdr_len, DMA_= TO_DEVICE); > > if (dma_mapping_error(dma_dev, hdr_dma)) > > return -ENOMEM; > > @@ -338,6 +400,8 @@ static int virtnet_xsk_pool_disable(struct net_devi= ce *dev, u16 qid) > > err1 =3D virtnet_sq_bind_xsk_pool(vi, sq, NULL); > > err2 =3D virtnet_rq_bind_xsk_pool(vi, rq, NULL); > > > > + kfree(rq->xsk.xsk_buffs); > > + > > return err1 | err2; > > } > > > > diff --git a/drivers/net/virtio/xsk.h b/drivers/net/virtio/xsk.h > > index 7ebc9bda7aee..bef41a3f954e 100644 > > --- a/drivers/net/virtio/xsk.h > > +++ b/drivers/net/virtio/xsk.h > > @@ -23,4 +23,6 @@ int virtnet_xsk_pool_setup(struct net_device *dev, st= ruct netdev_bpf *xdp); > > bool virtnet_xsk_xmit(struct virtnet_sq *sq, struct xsk_buff_pool *poo= l, > > int budget); > > int virtnet_xsk_wakeup(struct net_device *dev, u32 qid, u32 flag); > > +int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct virtnet_rq= *rq, > > + struct xsk_buff_pool *pool, gfp_t gfp); > > #endif > > -- > > 2.32.0.3.g01195cf9f > > >