From a6bf5703f17bdbd775c0e6837dd2d5b1c344e28c Mon Sep 17 00:00:00 2001 From: Haiyang Zhang Date: Fri, 28 Jan 2022 18:03:38 -0800 Subject: [PATCH] net: mana: Reuse XDP dropped page Reuse the dropped page in RX path to save page allocation overhead. Signed-off-by: Haiyang Zhang Signed-off-by: David S. Miller --- drivers/net/ethernet/microsoft/mana/mana.h | 1 + drivers/net/ethernet/microsoft/mana/mana_en.c | 15 +++++++++++++-- 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/microsoft/mana/mana.h b/drivers/net/ethernet/microsoft/mana/mana.h index 8ead960..d36405a 100644 --- a/drivers/net/ethernet/microsoft/mana/mana.h +++ b/drivers/net/ethernet/microsoft/mana/mana.h @@ -310,6 +310,7 @@ struct mana_rxq { struct bpf_prog __rcu *bpf_prog; struct xdp_rxq_info xdp_rxq; + struct page *xdp_save_page; /* MUST BE THE LAST MEMBER: * Each receive buffer has an associated mana_recv_buf_oob. diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index 12067bf..69e791e 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -1059,7 +1059,9 @@ drop_xdp: u64_stats_update_end(&rx_stats->syncp); drop: - free_page((unsigned long)buf_va); + WARN_ON_ONCE(rxq->xdp_save_page); + rxq->xdp_save_page = virt_to_page(buf_va); + ++ndev->stats.rx_dropped; return; @@ -1116,7 +1118,13 @@ static void mana_process_rx_cqe(struct mana_rxq *rxq, struct mana_cq *cq, rxbuf_oob = &rxq->rx_oobs[curr]; WARN_ON_ONCE(rxbuf_oob->wqe_inf.wqe_size_in_bu != 1); - new_page = alloc_page(GFP_ATOMIC); + /* Reuse XDP dropped page if available */ + if (rxq->xdp_save_page) { + new_page = rxq->xdp_save_page; + rxq->xdp_save_page = NULL; + } else { + new_page = alloc_page(GFP_ATOMIC); + } if (new_page) { da = dma_map_page(dev, new_page, XDP_PACKET_HEADROOM, rxq->datasize, @@ -1403,6 +1411,9 @@ static void mana_destroy_rxq(struct mana_port_context *apc, mana_deinit_cq(apc, &rxq->rx_cq); + if (rxq->xdp_save_page) + __free_page(rxq->xdp_save_page); + for (i = 0; i < rxq->num_rx_buf; i++) { rx_oob = &rxq->rx_oobs[i]; -- 2.7.4