From mboxrd@z Thu Jan 1 00:00:00 1970 From: Edward Cree Subject: [RFC PATCH v2 net-next 04/12] net: core: Another step of skb receive list processing Date: Tue, 26 Jun 2018 19:18:49 +0100 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: To: , Return-path: Received: from dispatch1-us1.ppe-hosted.com ([67.231.154.164]:44650 "EHLO dispatch1-us1.ppe-hosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751541AbeFZSS6 (ORCPT ); Tue, 26 Jun 2018 14:18:58 -0400 In-Reply-To: Content-Language: en-GB Sender: netdev-owner@vger.kernel.org List-ID: netif_receive_skb_list_internal() now processes a list and hands it on to the next function. Signed-off-by: Edward Cree --- net/core/dev.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 69 insertions(+), 4 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 0ab16941a651..27980c13ad5c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4729,6 +4729,14 @@ static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) return ret; } +static void __netif_receive_skb_list(struct sk_buff_head *list) +{ + struct sk_buff *skb; + + while ((skb = __skb_dequeue(list)) != NULL) + __netif_receive_skb(skb); +} + static int netif_receive_skb_internal(struct sk_buff *skb) { int ret; @@ -4769,6 +4777,64 @@ static int netif_receive_skb_internal(struct sk_buff *skb) return ret; } +static void netif_receive_skb_list_internal(struct sk_buff_head *list) +{ + /* Two sublists so we can go back and forth between them */ + struct sk_buff_head sublist, sublist2; + struct bpf_prog *xdp_prog = NULL; + struct sk_buff *skb; + + __skb_queue_head_init(&sublist); + + while ((skb = __skb_dequeue(list)) != NULL) { + net_timestamp_check(netdev_tstamp_prequeue, skb); + if (skb_defer_rx_timestamp(skb)) + /* Handled, don't add to sublist */ + continue; + __skb_queue_tail(&sublist, skb); + } + + __skb_queue_head_init(&sublist2); + if (static_branch_unlikely(&generic_xdp_needed_key)) { + preempt_disable(); + rcu_read_lock(); + while ((skb = __skb_dequeue(&sublist)) != NULL) { + xdp_prog = rcu_dereference(skb->dev->xdp_prog); + if (do_xdp_generic(xdp_prog, skb) != XDP_PASS) + /* Dropped, don't add to sublist */ + continue; + __skb_queue_tail(&sublist2, skb); + } + rcu_read_unlock(); + preempt_enable(); + /* Move all packets onto first sublist */ + skb_queue_splice_init(&sublist2, &sublist); + } + + rcu_read_lock(); +#ifdef CONFIG_RPS + if (static_key_false(&rps_needed)) { + while ((skb = __skb_dequeue(&sublist)) != NULL) { + struct rps_dev_flow voidflow, *rflow = &voidflow; + int cpu = get_rps_cpu(skb->dev, skb, &rflow); + + if (cpu >= 0) { + enqueue_to_backlog(skb, cpu, &rflow->last_qtail); + /* Handled, don't add to sublist */ + continue; + } + + __skb_queue_tail(&sublist2, skb); + } + + /* Move all packets onto first sublist */ + skb_queue_splice_init(&sublist2, &sublist); + } +#endif + __netif_receive_skb_list(&sublist); + rcu_read_unlock(); +} + /** * netif_receive_skb - process receive buffer from network * @skb: buffer to process @@ -4797,8 +4863,8 @@ EXPORT_SYMBOL(netif_receive_skb); * @list: list of skbs to process. Must not be shareable (e.g. it may * be on the stack) * - * For now, just calls netif_receive_skb() in a loop, ignoring the - * return value. + * Since return value of netif_receive_skb() is normally ignored, and + * wouldn't be meaningful for a list, this function returns void. * * This function may only be called from softirq context and interrupts * should be enabled. @@ -4809,8 +4875,7 @@ void netif_receive_skb_list(struct sk_buff_head *list) skb_queue_for_each(skb, list) trace_netif_receive_skb_list_entry(skb); - while ((skb = __skb_dequeue(list)) != NULL) - netif_receive_skb_internal(skb); + netif_receive_skb_list_internal(list); } EXPORT_SYMBOL(netif_receive_skb_list);