From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesper Dangaard Brouer Subject: [bpf-next V1 PATCH 8/8] bpf/xdp: devmap can avoid calling ndo_xdp_flush Date: Wed, 30 May 2018 20:01:13 +0200 Message-ID: <152770327343.20510.17045843025201198801.stgit@firesoul> References: <152770312703.20510.5854417568847239931.stgit@firesoul> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: John Fastabend , makita.toshiaki@lab.ntt.co.jp To: netdev@vger.kernel.org, Daniel Borkmann , Alexei Starovoitov , Jesper Dangaard Brouer Return-path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:50320 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932113AbeE3SBP (ORCPT ); Wed, 30 May 2018 14:01:15 -0400 In-Reply-To: <152770312703.20510.5854417568847239931.stgit@firesoul> Sender: netdev-owner@vger.kernel.org List-ID: The XDP_REDIRECT map devmap can avoid using ndo_xdp_flush, by instead instructing ndo_xdp_xmit to flush via XDP_XMIT_FLUSH flag in appropriate places. Notice after this patch it is possible to remove ndo_xdp_flush completely, as this is the last user of ndo_xdp_flush. This is left for later patches, to keep driver changes separate. Signed-off-by: Jesper Dangaard Brouer --- kernel/bpf/devmap.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-) diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 04fbd75a5274..9c846a7a8cff 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -217,7 +217,7 @@ void __dev_map_insert_ctx(struct bpf_map *map, u32 bit) } static int bq_xmit_all(struct bpf_dtab_netdev *obj, - struct xdp_bulk_queue *bq) + struct xdp_bulk_queue *bq, bool flush) { struct net_device *dev = obj->dev; int sent = 0, drops = 0, err = 0; @@ -232,7 +232,8 @@ static int bq_xmit_all(struct bpf_dtab_netdev *obj, prefetch(xdpf); } - sent = dev->netdev_ops->ndo_xdp_xmit(dev, bq->count, bq->q, 0); + sent = dev->netdev_ops->ndo_xdp_xmit(dev, bq->count, bq->q, + flush ? XDP_XMIT_FLUSH : 0); if (sent < 0) { err = sent; sent = 0; @@ -276,7 +277,6 @@ void __dev_map_flush(struct bpf_map *map) for_each_set_bit(bit, bitmap, map->max_entries) { struct bpf_dtab_netdev *dev = READ_ONCE(dtab->netdev_map[bit]); struct xdp_bulk_queue *bq; - struct net_device *netdev; /* This is possible if the dev entry is removed by user space * between xdp redirect and flush op. @@ -287,10 +287,7 @@ void __dev_map_flush(struct bpf_map *map) __clear_bit(bit, bitmap); bq = this_cpu_ptr(dev->bulkq); - bq_xmit_all(dev, bq); - netdev = dev->dev; - if (likely(netdev->netdev_ops->ndo_xdp_flush)) - netdev->netdev_ops->ndo_xdp_flush(netdev); + bq_xmit_all(dev, bq, true); } } @@ -320,7 +317,7 @@ static int bq_enqueue(struct bpf_dtab_netdev *obj, struct xdp_frame *xdpf, struct xdp_bulk_queue *bq = this_cpu_ptr(obj->bulkq); if (unlikely(bq->count == DEV_MAP_BULK_SIZE)) - bq_xmit_all(obj, bq); + bq_xmit_all(obj, bq, false); /* Ingress dev_rx will be the same for all xdp_frame's in * bulk_queue, because bq stored per-CPU and must be flushed @@ -359,8 +356,7 @@ static void *dev_map_lookup_elem(struct bpf_map *map, void *key) static void dev_map_flush_old(struct bpf_dtab_netdev *dev) { - if (dev->dev->netdev_ops->ndo_xdp_flush) { - struct net_device *fl = dev->dev; + if (dev->dev->netdev_ops->ndo_xdp_xmit) { struct xdp_bulk_queue *bq; unsigned long *bitmap; @@ -371,9 +367,7 @@ static void dev_map_flush_old(struct bpf_dtab_netdev *dev) __clear_bit(dev->bit, bitmap); bq = per_cpu_ptr(dev->bulkq, cpu); - bq_xmit_all(dev, bq); - - fl->netdev_ops->ndo_xdp_flush(dev->dev); + bq_xmit_all(dev, bq, true); } } }