From: Alexander Aring <aring@mojatatu.com>
Date: Mon, 4 Dec 2017 18:40:00 -0500
Subject: net: sched: sch_api: rearrange init handling
Patch-mainline: v4.16-rc1
Git-commit: 54160ef6ec64e5a27b8f4ab4105ae81a57064dca
References: bsc#1109837

This patch fixes the following checkpatch error:

ERROR: do not use assignment in if condition

by rearranging the if condition to execute init callback only if init
callback exists. The whole setup afterwards is called in any case,
doesn't matter if init callback is set or not. This patch has the same
behaviour as before, just without assign err variable in if condition.
It also makes the code easier to read.

Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/sched/sch_api.c |   83 +++++++++++++++++++++++++++++++---------------------
 1 file changed, 50 insertions(+), 33 deletions(-)

--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1062,43 +1062,60 @@ static struct Qdisc *qdisc_create(struct
 		netdev_info(dev, "Caught tx_queue_len zero misconfig\n");
 	}
 
-	if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
-		if (tca[TCA_STAB]) {
-			stab = qdisc_get_stab(tca[TCA_STAB]);
-			if (IS_ERR(stab)) {
-				err = PTR_ERR(stab);
-				goto err_out4;
-			}
-			rcu_assign_pointer(sch->stab, stab);
-		}
-		if (tca[TCA_RATE]) {
-			seqcount_t *running;
+	if (ops->init) {
+		err = ops->init(sch, tca[TCA_OPTIONS]);
+		if (err != 0)
+			goto err_out5;
+	}
 
-			err = -EOPNOTSUPP;
-			if (sch->flags & TCQ_F_MQROOT)
-				goto err_out4;
-
-			if (sch->parent != TC_H_ROOT &&
-			    !(sch->flags & TCQ_F_INGRESS) &&
-			    (!p || !(p->flags & TCQ_F_MQROOT)))
-				running = qdisc_root_sleeping_running(sch);
-			else
-				running = &sch->running;
-
-			err = gen_new_estimator(&sch->bstats,
-						sch->cpu_bstats,
-						&sch->rate_est,
-						NULL,
-						running,
-						tca[TCA_RATE]);
-			if (err)
-				goto err_out4;
-		}
+	if (qdisc_is_percpu_stats(sch)) {
+		sch->cpu_bstats =
+			netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
+		if (!sch->cpu_bstats)
+			goto err_out4;
+
+		sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
+		if (!sch->cpu_qstats)
+			goto err_out4;
+	}
 
-		qdisc_hash_add(sch, false);
+	if (tca[TCA_STAB]) {
+		stab = qdisc_get_stab(tca[TCA_STAB]);
+		if (IS_ERR(stab)) {
+			err = PTR_ERR(stab);
+			goto err_out4;
+		}
+		rcu_assign_pointer(sch->stab, stab);
+	}
+	if (tca[TCA_RATE]) {
+		seqcount_t *running;
 
-		return sch;
+		err = -EOPNOTSUPP;
+		if (sch->flags & TCQ_F_MQROOT)
+			goto err_out4;
+
+		if (sch->parent != TC_H_ROOT &&
+		    !(sch->flags & TCQ_F_INGRESS) &&
+		    (!p || !(p->flags & TCQ_F_MQROOT)))
+			running = qdisc_root_sleeping_running(sch);
+		else
+			running = &sch->running;
+
+		err = gen_new_estimator(&sch->bstats,
+					sch->cpu_bstats,
+					&sch->rate_est,
+					NULL,
+					running,
+					tca[TCA_RATE]);
+		if (err)
+			goto err_out4;
 	}
+
+	qdisc_hash_add(sch, false);
+
+	return sch;
+
+err_out5:
 	/* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */
 	if (ops->destroy)
 		ops->destroy(sch);