From d2788d34885d4ce5ba17a8996fd95d28942e574e Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Sat, 9 May 2015 22:51:32 +0200 Subject: net: sched: further simplify handle_ing Ingress qdisc has no other purpose than calling into tc_classify() that executes attached classifier(s) and action(s). It has a 1:1 relationship to dev->ingress_queue. After having commit 087c1a601ad7 ("net: sched: run ingress qdisc without locks") removed the central ingress lock, one major contention point is gone. The extra indirection layers however, are not necessary for calling into ingress qdisc. pktgen calling locally into netif_receive_skb() with a dummy u32, single CPU result on a Supermicro X10SLM-F, Xeon E3-1240: before ~21,1 Mpps, after patch ~22,9 Mpps. We can redirect the private classifier list to the netdev directly, without changing any classifier API bits (!) and execute on that from handle_ing() side. The __QDISC_STATE_DEACTIVATE test can be removed, ingress qdisc doesn't have a queue and thus dev_deactivate_queue() is also not applicable, ingress_cl_list provides similar behaviour. In other words, ingress qdisc acts like TCQ_F_BUILTIN qdisc. One next possible step is the removal of the dev's ingress (dummy) netdev_queue, and to only have the list member in the netdevice itself. Note, the filter chain is RCU protected and individual filter elements are being kfree'd by sched subsystem after RCU grace period. RCU read lock is being held by __netif_receive_skb_core(). Joint work with Alexei Starovoitov. Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- include/linux/netdevice.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 1899c74a7127..c4e1caf6056f 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1655,7 +1655,11 @@ struct net_device { rx_handler_func_t __rcu *rx_handler; void __rcu *rx_handler_data; +#if CONFIG_NET_CLS_ACT + struct tcf_proto __rcu *ingress_cl_list; +#endif struct netdev_queue __rcu *ingress_queue; + unsigned char broadcast[MAX_ADDR_LEN]; #ifdef CONFIG_RFS_ACCEL struct cpu_rmap *rx_cpu_rmap; -- cgit v1.2.3