From: John Fastabend <john.fastabend@gmail.com>
Date: Thu, 7 Dec 2017 09:55:26 -0800
Subject: net: sched: a dflt qdisc may be used with per cpu stats
Patch-mainline: v4.16-rc1
Git-commit: d59f5ffa59d80ff3a2f3b56a9acea4310974c6d1
References: bsc#1109837

Enable dflt qdisc support for per cpu stats before this patch a dflt
qdisc was required to use the global statistics qstats and bstats.

This adds a static flags field to qdisc_ops that is propagated
into qdisc->flags in qdisc allocate call. This allows the allocation
block to completely allocate the qdisc object so we don't have
dangling allocations after qdisc init.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/sched/sch_generic.c |   13 +++++++++++++
 1 file changed, 13 insertions(+)

--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -644,6 +644,19 @@ struct Qdisc *qdisc_alloc(struct netdev_
 		}
 	}
 
+	if (ops->static_flags & TCQ_F_CPUSTATS) {
+		sch->cpu_bstats =
+			netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
+		if (!sch->cpu_bstats)
+			goto errout1;
+
+		sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
+		if (!sch->cpu_qstats) {
+			free_percpu(sch->cpu_bstats);
+			goto errout1;
+		}
+	}
+
 	spin_lock_init(&sch->busylock);
 	lockdep_set_class(&sch->busylock,
 			  dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);