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Tsirkin" , Jason Wang CC: Xuan Zhuo , =?UTF-8?q?Eugenio=20P=C3=A9rez?= , Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , David Wei , , , Subject: [PATCH 1/2] virtio_net: add page pool support for buffer allocation Date: Tue, 6 Jan 2026 14:19:23 -0800 Message-ID: <20260106221924.123856-2-vishs@meta.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260106221924.123856-1-vishs@meta.com> References: <20260106221924.123856-1-vishs@meta.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Authority-Analysis: v=2.4 cv=dtPWylg4 c=1 sm=1 tr=0 ts=695d8a71 cx=c_pps a=CB4LiSf2rd0gKozIdrpkBw==:117 a=CB4LiSf2rd0gKozIdrpkBw==:17 a=vUbySO9Y5rIA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VabnemYjAAAA:8 a=gD-bKePctUg2aiC0oG0A:9 a=gKebqoRLp9LExxC7YDUY:22 X-Proofpoint-GUID: R2qSMBeIWkGuvulpD_EIXvPECPtMz6_p X-Proofpoint-ORIG-GUID: R2qSMBeIWkGuvulpD_EIXvPECPtMz6_p X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTA2MDE5MyBTYWx0ZWRfXy2/UboZZMjwt A4ckb74kW478WUgLbdRpPWLGEi7En0qfPhw8hE3P2MhMjl7q0a/xyzHg61E8/E4uy3RJdnZkyLS NaoX+b1IcvZ44+TIdyj0/1sU/g+0W2Lzr7aQmy0xAMkcxPRC/sIKW9OG+F++E3al+G6/NX2E307 yWbnj9HSiDU4aBrLeFiaa6WeoH/4Rgrl6R+r/Ul9xcZ70pj2/49AvYFGCmlIat0AFhhW3poB2Og kZZn0a8tEKryFxVx8NcdTjA+oJnn3V0NRejhXV5+5hMaiXbOFw6+1ZMrij3DefiRIyrIBIdC6Ag BgV9kztEW9vqW2A91y1wG4xouUGs+0qZIJ0UOLIB+zTBBlEg7ttERliRB3yt0Nt/3SyoqdSfRKB sIqDlq+aBbv2VOZ19EWcr7awJDtVk+qQiSALD5Ahf+IT4jMGnXeN2LbhxXTByYTlkMysLCTM2IV h6sKmGsvYgzkD1sqNCA== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2026-01-06_02,2026-01-06_01,2025-10-01_01 Content-Type: text/plain; charset="utf-8" Use page_pool for RX buffer allocation in mergeable and small buffer modes. skb_mark_for_recycle() enables page reuse. Big packets mode is unchanged because it uses page->private for linked list chaining of multiple pages per buffer, which conflicts with page_pool's internal use of page->private. Page pools are created in ndo_open and destroyed in remove (not ndo_close). This follows existing driver behavior where RX buffers remain in the virtqueue across open/close cycles and are only freed on device removal. The rx_mode_work_enabled flag prevents virtnet_rx_mode_work() from sending control virtqueue commands while ndo_close is tearing down device state. With MEM_TYPE_PAGE_POOL, xdp_rxq_info_unreg() calls page_pool_destroy() during close, and concurrent rx_mode_work can cause virtqueue corruption. The check is after rtnl_lock() to synchronize with ndo_close(), which sets the flag under the same lock. Signed-off-by: Vishwanath Seshagiri --- drivers/net/virtio_net.c | 246 ++++++++++++++++++++++++++++++++------- 1 file changed, 205 insertions(+), 41 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 22d894101c01..c36663525c17 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -26,6 +26,7 @@ #include #include #include +#include =20 static int napi_weight =3D NAPI_POLL_WEIGHT; module_param(napi_weight, int, 0444); @@ -359,6 +360,8 @@ struct receive_queue { /* Page frag for packet buffer allocation. */ struct page_frag alloc_frag; =20 + struct page_pool *page_pool; + /* RX: fragments + linear part + virtio header */ struct scatterlist sg[MAX_SKB_FRAGS + 2]; =20 @@ -524,11 +527,13 @@ static int virtnet_xdp_handler(struct bpf_prog *xdp_p= rog, struct xdp_buff *xdp, struct virtnet_rq_stats *stats); static void virtnet_receive_done(struct virtnet_info *vi, struct receive_q= ueue *rq, struct sk_buff *skb, u8 flags); -static struct sk_buff *virtnet_skb_append_frag(struct sk_buff *head_skb, +static struct sk_buff *virtnet_skb_append_frag(struct receive_queue *rq, + struct sk_buff *head_skb, struct sk_buff *curr_skb, struct page *page, void *buf, int len, int truesize); static void virtnet_xsk_completed(struct send_queue *sq, int num); +static void free_unused_bufs(struct virtnet_info *vi); =20 enum virtnet_xmit_type { VIRTNET_XMIT_TYPE_SKB, @@ -709,15 +714,24 @@ static struct page *get_a_page(struct receive_queue *= rq, gfp_t gfp_mask) return p; } =20 +static void virtnet_put_page(struct receive_queue *rq, struct page *page, + bool allow_direct) +{ + if (rq->page_pool) + page_pool_put_page(rq->page_pool, page, -1, allow_direct); + else + put_page(page); +} + static void virtnet_rq_free_buf(struct virtnet_info *vi, struct receive_queue *rq, void *buf) { if (vi->mergeable_rx_bufs) - put_page(virt_to_head_page(buf)); + virtnet_put_page(rq, virt_to_head_page(buf), false); else if (vi->big_packets) give_pages(rq, buf); else - put_page(virt_to_head_page(buf)); + virtnet_put_page(rq, virt_to_head_page(buf), false); } =20 static void enable_delayed_refill(struct virtnet_info *vi) @@ -894,9 +908,11 @@ static struct sk_buff *page_to_skb(struct virtnet_info= *vi, if (unlikely(!skb)) return NULL; =20 - page =3D (struct page *)page->private; - if (page) - give_pages(rq, page); + if (!rq->page_pool) { + page =3D (struct page *)page->private; + if (page) + give_pages(rq, page); + } goto ok; } =20 @@ -931,7 +947,10 @@ static struct sk_buff *page_to_skb(struct virtnet_info= *vi, skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset, frag_size, truesize); len -=3D frag_size; - page =3D (struct page *)page->private; + if (!rq->page_pool) + page =3D (struct page *)page->private; + else + page =3D NULL; offset =3D 0; } =20 @@ -942,7 +961,7 @@ static struct sk_buff *page_to_skb(struct virtnet_info = *vi, hdr =3D skb_vnet_common_hdr(skb); memcpy(hdr, hdr_p, hdr_len); if (page_to_free) - put_page(page_to_free); + virtnet_put_page(rq, page_to_free, true); =20 return skb; } @@ -982,15 +1001,10 @@ static void virtnet_rq_unmap(struct receive_queue *r= q, void *buf, u32 len) static void *virtnet_rq_get_buf(struct receive_queue *rq, u32 *len, void *= *ctx) { struct virtnet_info *vi =3D rq->vq->vdev->priv; - void *buf; =20 BUG_ON(vi->big_packets && !vi->mergeable_rx_bufs); =20 - buf =3D virtqueue_get_buf_ctx(rq->vq, len, ctx); - if (buf) - virtnet_rq_unmap(rq, buf, *len); - - return buf; + return virtqueue_get_buf_ctx(rq->vq, len, ctx); } =20 static void virtnet_rq_init_one_sg(struct receive_queue *rq, void *buf, u3= 2 len) @@ -1084,9 +1098,6 @@ static void virtnet_rq_unmap_free_buf(struct virtqueu= e *vq, void *buf) return; } =20 - if (!vi->big_packets || vi->mergeable_rx_bufs) - virtnet_rq_unmap(rq, buf, 0); - virtnet_rq_free_buf(vi, rq, buf); } =20 @@ -1352,7 +1363,7 @@ static int xsk_append_merge_buffer(struct virtnet_inf= o *vi, =20 truesize =3D len; =20 - curr_skb =3D virtnet_skb_append_frag(head_skb, curr_skb, page, + curr_skb =3D virtnet_skb_append_frag(rq, head_skb, curr_skb, page, buf, len, truesize); if (!curr_skb) { put_page(page); @@ -1788,7 +1799,7 @@ static int virtnet_xdp_xmit(struct net_device *dev, return ret; } =20 -static void put_xdp_frags(struct xdp_buff *xdp) +static void put_xdp_frags(struct xdp_buff *xdp, struct receive_queue *rq) { struct skb_shared_info *shinfo; struct page *xdp_page; @@ -1798,7 +1809,7 @@ static void put_xdp_frags(struct xdp_buff *xdp) shinfo =3D xdp_get_shared_info_from_buff(xdp); for (i =3D 0; i < shinfo->nr_frags; i++) { xdp_page =3D skb_frag_page(&shinfo->frags[i]); - put_page(xdp_page); + virtnet_put_page(rq, xdp_page, true); } } } @@ -1914,7 +1925,7 @@ static struct page *xdp_linearize_page(struct net_dev= ice *dev, off =3D buf - page_address(p); =20 if (check_mergeable_len(dev, ctx, buflen)) { - put_page(p); + virtnet_put_page(rq, p, true); goto err_buf; } =20 @@ -1922,14 +1933,14 @@ static struct page *xdp_linearize_page(struct net_d= evice *dev, * is sending packet larger than the MTU. */ if ((page_off + buflen + tailroom) > PAGE_SIZE) { - put_page(p); + virtnet_put_page(rq, p, true); goto err_buf; } =20 memcpy(page_address(page) + page_off, page_address(p) + off, buflen); page_off +=3D buflen; - put_page(p); + virtnet_put_page(rq, p, true); } =20 /* Headroom does not contribute to packet length */ @@ -1979,7 +1990,7 @@ static struct sk_buff *receive_small_xdp(struct net_d= evice *dev, unsigned int headroom =3D vi->hdr_len + header_offset; struct virtio_net_hdr_mrg_rxbuf *hdr =3D buf + header_offset; struct page *page =3D virt_to_head_page(buf); - struct page *xdp_page; + struct page *xdp_page =3D NULL; unsigned int buflen; struct xdp_buff xdp; struct sk_buff *skb; @@ -2013,7 +2024,7 @@ static struct sk_buff *receive_small_xdp(struct net_d= evice *dev, goto err_xdp; =20 buf =3D page_address(xdp_page); - put_page(page); + virtnet_put_page(rq, page, true); page =3D xdp_page; } =20 @@ -2045,13 +2056,19 @@ static struct sk_buff *receive_small_xdp(struct net= _device *dev, if (metasize) skb_metadata_set(skb, metasize); =20 + if (rq->page_pool && !xdp_page) + skb_mark_for_recycle(skb); + return skb; =20 err_xdp: u64_stats_inc(&stats->xdp_drops); err: u64_stats_inc(&stats->drops); - put_page(page); + if (xdp_page) + put_page(page); + else + virtnet_put_page(rq, page, true); xdp_xmit: return NULL; } @@ -2099,12 +2116,15 @@ static struct sk_buff *receive_small(struct net_dev= ice *dev, } =20 skb =3D receive_small_build_skb(vi, xdp_headroom, buf, len); - if (likely(skb)) + if (likely(skb)) { + if (rq->page_pool) + skb_mark_for_recycle(skb); return skb; + } =20 err: u64_stats_inc(&stats->drops); - put_page(page); + virtnet_put_page(rq, page, true); return NULL; } =20 @@ -2159,7 +2179,7 @@ static void mergeable_buf_free(struct receive_queue *= rq, int num_buf, } u64_stats_add(&stats->bytes, len); page =3D virt_to_head_page(buf); - put_page(page); + virtnet_put_page(rq, page, true); } } =20 @@ -2270,7 +2290,7 @@ static int virtnet_build_xdp_buff_mrg(struct net_devi= ce *dev, offset =3D buf - page_address(page); =20 if (check_mergeable_len(dev, ctx, len)) { - put_page(page); + virtnet_put_page(rq, page, true); goto err; } =20 @@ -2289,7 +2309,7 @@ static int virtnet_build_xdp_buff_mrg(struct net_devi= ce *dev, return 0; =20 err: - put_xdp_frags(xdp); + put_xdp_frags(xdp, rq); return -EINVAL; } =20 @@ -2364,7 +2384,7 @@ static void *mergeable_xdp_get_buf(struct virtnet_inf= o *vi, =20 *frame_sz =3D PAGE_SIZE; =20 - put_page(*page); + virtnet_put_page(rq, *page, true); =20 *page =3D xdp_page; =20 @@ -2386,6 +2406,7 @@ static struct sk_buff *receive_mergeable_xdp(struct n= et_device *dev, struct page *page =3D virt_to_head_page(buf); int offset =3D buf - page_address(page); unsigned int xdp_frags_truesz =3D 0; + struct page *org_page =3D page; struct sk_buff *head_skb; unsigned int frame_sz; struct xdp_buff xdp; @@ -2410,6 +2431,8 @@ static struct sk_buff *receive_mergeable_xdp(struct n= et_device *dev, head_skb =3D build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz); if (unlikely(!head_skb)) break; + if (rq->page_pool && page =3D=3D org_page) + skb_mark_for_recycle(head_skb); return head_skb; =20 case XDP_TX: @@ -2420,10 +2443,13 @@ static struct sk_buff *receive_mergeable_xdp(struct= net_device *dev, break; } =20 - put_xdp_frags(&xdp); + put_xdp_frags(&xdp, rq); =20 err_xdp: - put_page(page); + if (page !=3D org_page) + put_page(page); + else + virtnet_put_page(rq, page, true); mergeable_buf_free(rq, num_buf, dev, stats); =20 u64_stats_inc(&stats->xdp_drops); @@ -2431,7 +2457,8 @@ static struct sk_buff *receive_mergeable_xdp(struct n= et_device *dev, return NULL; } =20 -static struct sk_buff *virtnet_skb_append_frag(struct sk_buff *head_skb, +static struct sk_buff *virtnet_skb_append_frag(struct receive_queue *rq, + struct sk_buff *head_skb, struct sk_buff *curr_skb, struct page *page, void *buf, int len, int truesize) @@ -2463,7 +2490,7 @@ static struct sk_buff *virtnet_skb_append_frag(struct= sk_buff *head_skb, =20 offset =3D buf - page_address(page); if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) { - put_page(page); + virtnet_put_page(rq, page, true); skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1, len, truesize); } else { @@ -2512,10 +2539,13 @@ static struct sk_buff *receive_mergeable(struct net= _device *dev, } =20 head_skb =3D page_to_skb(vi, rq, page, offset, len, truesize, headroom); + if (unlikely(!head_skb)) + goto err_skb; + curr_skb =3D head_skb; =20 - if (unlikely(!curr_skb)) - goto err_skb; + if (rq->page_pool) + skb_mark_for_recycle(head_skb); while (--num_buf) { buf =3D virtnet_rq_get_buf(rq, &len, &ctx); if (unlikely(!buf)) { @@ -2534,7 +2564,7 @@ static struct sk_buff *receive_mergeable(struct net_d= evice *dev, goto err_skb; =20 truesize =3D mergeable_ctx_to_truesize(ctx); - curr_skb =3D virtnet_skb_append_frag(head_skb, curr_skb, page, + curr_skb =3D virtnet_skb_append_frag(rq, head_skb, curr_skb, page, buf, len, truesize); if (!curr_skb) goto err_skb; @@ -2544,7 +2574,7 @@ static struct sk_buff *receive_mergeable(struct net_d= evice *dev, return head_skb; =20 err_skb: - put_page(page); + virtnet_put_page(rq, page, true); mergeable_buf_free(rq, num_buf, dev, stats); =20 err_buf: @@ -2683,6 +2713,8 @@ static void receive_buf(struct virtnet_info *vi, stru= ct receive_queue *rq, static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue= *rq, gfp_t gfp) { + unsigned int offset; + struct page *page; char *buf; unsigned int xdp_headroom =3D virtnet_get_headroom(vi); void *ctx =3D (void *)(unsigned long)xdp_headroom; @@ -2692,6 +2724,24 @@ static int add_recvbuf_small(struct virtnet_info *vi= , struct receive_queue *rq, len =3D SKB_DATA_ALIGN(len) + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); =20 + if (rq->page_pool) { + page =3D page_pool_alloc_frag(rq->page_pool, &offset, len, gfp); + if (unlikely(!page)) + return -ENOMEM; + + buf =3D page_address(page) + offset; + buf +=3D VIRTNET_RX_PAD + xdp_headroom; + + sg_init_table(rq->sg, 1); + sg_set_buf(&rq->sg[0], buf, vi->hdr_len + GOOD_PACKET_LEN); + + err =3D virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp); + if (err < 0) + page_pool_put_page(rq->page_pool, + virt_to_head_page(buf), -1, false); + return err; + } + if (unlikely(!skb_page_frag_refill(len, &rq->alloc_frag, gfp))) return -ENOMEM; =20 @@ -2786,6 +2836,8 @@ static int add_recvbuf_mergeable(struct virtnet_info = *vi, unsigned int tailroom =3D headroom ? sizeof(struct skb_shared_info) : 0; unsigned int room =3D SKB_DATA_ALIGN(headroom + tailroom); unsigned int len, hole; + unsigned int offset; + struct page *page; void *ctx; char *buf; int err; @@ -2796,6 +2848,39 @@ static int add_recvbuf_mergeable(struct virtnet_info= *vi, */ len =3D get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room); =20 + if (rq->page_pool) { + page =3D page_pool_alloc_frag(rq->page_pool, &offset, + len + room, gfp); + if (unlikely(!page)) + return -ENOMEM; + + buf =3D page_address(page) + offset; + buf +=3D headroom; /* advance address leaving hole at front of pkt */ + + hole =3D PAGE_SIZE - (offset + len + room); + if (hole < len + room) { + /* To avoid internal fragmentation, if there is very likely not + * enough space for another buffer, add the remaining space to + * the current buffer. + * XDP core assumes that frame_size of xdp_buff and the length + * of the frag are PAGE_SIZE, so we disable the hole mechanism. + */ + if (!headroom) + len +=3D hole; + } + + ctx =3D mergeable_len_to_ctx(len + room, headroom); + + sg_init_table(rq->sg, 1); + sg_set_buf(&rq->sg[0], buf, len); + + err =3D virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp); + if (err < 0) + page_pool_put_page(rq->page_pool, + virt_to_head_page(buf), -1, false); + return err; + } + if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp))) return -ENOMEM; =20 @@ -3181,7 +3266,10 @@ static int virtnet_enable_queue_pair(struct virtnet_= info *vi, int qp_index) return err; =20 err =3D xdp_rxq_info_reg_mem_model(&vi->rq[qp_index].xdp_rxq, - MEM_TYPE_PAGE_SHARED, NULL); + vi->rq[qp_index].page_pool ? + MEM_TYPE_PAGE_POOL : + MEM_TYPE_PAGE_SHARED, + vi->rq[qp_index].page_pool); if (err < 0) goto err_xdp_reg_mem_model; =20 @@ -3221,11 +3309,77 @@ static void virtnet_update_settings(struct virtnet_= info *vi) vi->duplex =3D duplex; } =20 +static int virtnet_create_page_pools(struct virtnet_info *vi) +{ + int i, err; + + for (i =3D 0; i < vi->curr_queue_pairs; i++) { + struct receive_queue *rq =3D &vi->rq[i]; + struct page_pool_params pp_params =3D { 0 }; + + if (rq->page_pool) + continue; + + if (rq->xsk_pool) + continue; + + if (!vi->mergeable_rx_bufs && vi->big_packets) + continue; + + pp_params.order =3D 0; + pp_params.pool_size =3D virtqueue_get_vring_size(rq->vq); + pp_params.nid =3D dev_to_node(vi->vdev->dev.parent); + pp_params.dev =3D vi->vdev->dev.parent; + pp_params.netdev =3D vi->dev; + pp_params.napi =3D &rq->napi; + pp_params.flags =3D 0; + + rq->page_pool =3D page_pool_create(&pp_params); + if (IS_ERR(rq->page_pool)) { + err =3D PTR_ERR(rq->page_pool); + rq->page_pool =3D NULL; + goto err_cleanup; + } + } + return 0; + +err_cleanup: + while (--i >=3D 0) { + struct receive_queue *rq =3D &vi->rq[i]; + + if (rq->page_pool) { + page_pool_destroy(rq->page_pool); + rq->page_pool =3D NULL; + } + } + return err; +} + +static void virtnet_destroy_page_pools(struct virtnet_info *vi) +{ + int i; + + for (i =3D 0; i < vi->max_queue_pairs; i++) { + struct receive_queue *rq =3D &vi->rq[i]; + + if (rq->page_pool) { + page_pool_destroy(rq->page_pool); + rq->page_pool =3D NULL; + } + } +} + static int virtnet_open(struct net_device *dev) { struct virtnet_info *vi =3D netdev_priv(dev); int i, err; =20 + err =3D virtnet_create_page_pools(vi); + if (err) + return err; + + vi->rx_mode_work_enabled =3D true; + enable_delayed_refill(vi); =20 for (i =3D 0; i < vi->max_queue_pairs; i++) { @@ -3251,6 +3405,7 @@ static int virtnet_open(struct net_device *dev) return 0; =20 err_enable_qp: + vi->rx_mode_work_enabled =3D false; disable_delayed_refill(vi); cancel_delayed_work_sync(&vi->refill); =20 @@ -3856,6 +4011,8 @@ static int virtnet_close(struct net_device *dev) */ cancel_work_sync(&vi->config_work); =20 + vi->rx_mode_work_enabled =3D false; + for (i =3D 0; i < vi->max_queue_pairs; i++) { virtnet_disable_queue_pair(vi, i); virtnet_cancel_dim(vi, &vi->rq[i].dim); @@ -3892,6 +4049,11 @@ static void virtnet_rx_mode_work(struct work_struct = *work) =20 rtnl_lock(); =20 + if (!vi->rx_mode_work_enabled) { + rtnl_unlock(); + return; + } + *promisc_allmulti =3D !!(dev->flags & IFF_PROMISC); sg_init_one(sg, promisc_allmulti, sizeof(*promisc_allmulti)); =20 @@ -7193,6 +7355,8 @@ static void remove_vq_common(struct virtnet_info *vi) =20 free_receive_page_frags(vi); 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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , David Wei , , , Subject: [PATCH 2/2] selftests: virtio_net: add buffer circulation test Date: Tue, 6 Jan 2026 14:19:24 -0800 Message-ID: <20260106221924.123856-3-vishs@meta.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260106221924.123856-1-vishs@meta.com> References: <20260106221924.123856-1-vishs@meta.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTA2MDE5MyBTYWx0ZWRfX14rD0B4MHVra tYh1jJ3mpr/5HGiJETI9QJWH3H+of6tfvh9TIxvNVcxy8cj0/W0JnyY71zrBTKKOyJteo1ch8Qo 0hktQd3OZzhIJyrWGZo/3Q8Ttgl8Jj0atv3IqCNmsaKZoxP6GwXMlu0DEh/igi64VwNiBKjwtAi /zrzZ5Gu7PWXBjzdO0C/UzY5cbyxjfESxs889DOx23xY/dnBPyG16KqgchsY7Jqt0eX8lQND6JS xWJn7vOigCyoN+u9FrYqSjrE9Pu8FJMVWaDIdcnrKZwR+mCKFIZi/zlrV3M7upCDtPT682ttgKh AFUl5T79B61K6cR9vBZ0UyaIkk/XkZqo5m9cA56JT3Yx27zLXql9E4wYuMkk331n4Csb6MhkzuA B8NgNtv+s3FD4GbRT3i5Sg+FQYplMVYkKpFJlxFRQFCP1CNTFH7aocOPgpFuJp54RRPcBzpR3wj gv6d9V6cIHxDXi7QgqQ== X-Proofpoint-ORIG-GUID: t7wsrFEpDt0vdqOb7LS2endCp8XptD92 X-Authority-Analysis: v=2.4 cv=Zs/g6t7G c=1 sm=1 tr=0 ts=695d8a79 cx=c_pps a=MfjaFnPeirRr97d5FC5oHw==:117 a=MfjaFnPeirRr97d5FC5oHw==:17 a=vUbySO9Y5rIA:10 a=VkNPw1HP01LnGYTKEx00:22 a=-RNOp1hDGyVVwNzvGBsA:9 X-Proofpoint-GUID: t7wsrFEpDt0vdqOb7LS2endCp8XptD92 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2026-01-06_02,2026-01-06_01,2025-10-01_01 Content-Type: text/plain; charset="utf-8" Add iperf3-based test to verify RX buffer handling under load. Optionally logs page_pool tracepoints when available. --- .../drivers/net/virtio_net/basic_features.sh | 70 +++++++++++++++++++ 1 file changed, 70 insertions(+) diff --git a/tools/testing/selftests/drivers/net/virtio_net/basic_features.= sh b/tools/testing/selftests/drivers/net/virtio_net/basic_features.sh index cf8cf816ed48..c2c8023d2b92 100755 --- a/tools/testing/selftests/drivers/net/virtio_net/basic_features.sh +++ b/tools/testing/selftests/drivers/net/virtio_net/basic_features.sh @@ -6,6 +6,7 @@ ALL_TESTS=3D" initial_ping_test f_mac_test + buffer_circulation_test " =20 source virtio_net_common.sh @@ -16,6 +17,8 @@ source "$lib_dir"/../../../net/forwarding/lib.sh h1=3D${NETIFS[p1]} h2=3D${NETIFS[p2]} =20 +require_command iperf3 + h1_create() { simple_if_init $h1 $H1_IPV4/24 $H1_IPV6/64 @@ -83,6 +86,73 @@ f_mac_test() log_test "$test_name" } =20 +buffer_circulation_test() +{ + RET=3D0 + local test_name=3D"buffer circulation" + local tracefs=3D"/sys/kernel/tracing" + + setup_cleanup + setup_prepare + + ping -c 1 -I $h1 $H2_IPV4 >/dev/null + if [ $? -ne 0 ]; then + check_err 1 "Ping failed" + log_test "$test_name" + return + fi + + local rx_start=3D$(cat /sys/class/net/$h2/statistics/rx_packets) + local tx_start=3D$(cat /sys/class/net/$h1/statistics/tx_packets) + + if [ -d "$tracefs/events/page_pool" ]; then + echo > "$tracefs/trace" + echo 1 > "$tracefs/events/page_pool/enable" + fi + + iperf3 -s --bind-dev $h2 -p 5201 &>/dev/null & + local server_pid=3D$! + sleep 1 + + if ! kill -0 $server_pid 2>/dev/null; then + if [ -d "$tracefs/events/page_pool" ]; then + echo 0 > "$tracefs/events/page_pool/enable" + fi + check_err 1 "iperf3 server died" + log_test "$test_name" + return + fi + + iperf3 -c $H2_IPV4 --bind-dev $h1 -p 5201 -t 5 >/dev/null 2>&1 + local iperf_ret=3D$? + + kill $server_pid 2>/dev/null || true + wait $server_pid 2>/dev/null || true + + if [ -d "$tracefs/events/page_pool" ]; then + echo 0 > "$tracefs/events/page_pool/enable" + local trace=3D"$tracefs/trace" + local hold=3D$(grep -c "page_pool_state_hold" "$trace" 2>/dev/null) + local release=3D$(grep -c "page_pool_state_release" "$trace" 2>/dev/null) + log_info "page_pool events: hold=3D${hold:-0}, release=3D${release:-0}" + fi + + local rx_end=3D$(cat /sys/class/net/$h2/statistics/rx_packets) + local tx_end=3D$(cat /sys/class/net/$h1/statistics/tx_packets) + local rx_delta=3D$((rx_end - rx_start)) + local tx_delta=3D$((tx_end - tx_start)) + + log_info "Circulated TX:$tx_delta RX:$rx_delta" + + if [ $iperf_ret -ne 0 ]; then + check_err 1 "iperf3 failed" + elif [ "$rx_delta" -lt 10000 ]; then + check_err 1 "Too few packets: $rx_delta" + fi + + log_test "$test_name" +} + setup_prepare() { virtio_device_rebind $h1 --=20 2.47.3