1 files changed, 40 insertions, 28 deletions

diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index 79f9d6de6c85..2a0f3a513bfa 100644
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -168,6 +168,7 @@ static unsigned int fq_codel_drop(struct Qdisc *sch, unsigned int max_packets,
 		skb = dequeue_head(flow);
 		len += qdisc_pkt_len(skb);
 		mem += get_codel_cb(skb)->mem_usage;
+		tcf_set_drop_reason(skb, SKB_DROP_REASON_QDISC_OVERLIMIT);
 		__qdisc_drop(skb, to_free);
 	} while (++i < max_packets && len < threshold);
 
@@ -274,7 +275,7 @@ static void drop_func(struct sk_buff *skb, void *ctx)
 {
 	struct Qdisc *sch = ctx;
 
-	kfree_skb(skb);
+	kfree_skb_reason(skb, SKB_DROP_REASON_QDISC_CONGESTED);
 	qdisc_qstats_drop(sch);
 }
 
@@ -314,10 +315,8 @@ begin:
 	}
 	qdisc_bstats_update(sch, skb);
 	flow->deficit -= qdisc_pkt_len(skb);
-	/* We cant call qdisc_tree_reduce_backlog() if our qlen is 0,
-	 * or HTB crashes. Defer it for next round.
-	 */
-	if (q->cstats.drop_count && sch->q.qlen) {
+
+	if (q->cstats.drop_count) {
 		qdisc_tree_reduce_backlog(sch, q->cstats.drop_count,
 					  q->cstats.drop_len);
 		q->cstats.drop_count = 0;
@@ -396,44 +395,53 @@ static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt,
 	if (tb[TCA_FQ_CODEL_TARGET]) {
 		u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]);
 
-		q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT;
+		WRITE_ONCE(q->cparams.target,
+			   (target * NSEC_PER_USEC) >> CODEL_SHIFT);
 	}
 
 	if (tb[TCA_FQ_CODEL_CE_THRESHOLD]) {
 		u64 val = nla_get_u32(tb[TCA_FQ_CODEL_CE_THRESHOLD]);
 
-		q->cparams.ce_threshold = (val * NSEC_PER_USEC) >> CODEL_SHIFT;
+		WRITE_ONCE(q->cparams.ce_threshold,
+			   (val * NSEC_PER_USEC) >> CODEL_SHIFT);
 	}
 
 	if (tb[TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR])
-		q->cparams.ce_threshold_selector = nla_get_u8(tb[TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR]);
+		WRITE_ONCE(q->cparams.ce_threshold_selector,
+			   nla_get_u8(tb[TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR]));
 	if (tb[TCA_FQ_CODEL_CE_THRESHOLD_MASK])
-		q->cparams.ce_threshold_mask = nla_get_u8(tb[TCA_FQ_CODEL_CE_THRESHOLD_MASK]);
+		WRITE_ONCE(q->cparams.ce_threshold_mask,
+			   nla_get_u8(tb[TCA_FQ_CODEL_CE_THRESHOLD_MASK]));
 
 	if (tb[TCA_FQ_CODEL_INTERVAL]) {
 		u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]);
 
-		q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT;
+		WRITE_ONCE(q->cparams.interval,
+			   (interval * NSEC_PER_USEC) >> CODEL_SHIFT);
 	}
 
 	if (tb[TCA_FQ_CODEL_LIMIT])
-		sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]);
+		WRITE_ONCE(sch->limit,
+			   nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]));
 
 	if (tb[TCA_FQ_CODEL_ECN])
-		q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]);
+		WRITE_ONCE(q->cparams.ecn,
+			   !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]));
 
 	if (quantum)
-		q->quantum = quantum;
+		WRITE_ONCE(q->quantum, quantum);
 
 	if (tb[TCA_FQ_CODEL_DROP_BATCH_SIZE])
-		q->drop_batch_size = max(1U, nla_get_u32(tb[TCA_FQ_CODEL_DROP_BATCH_SIZE]));
+		WRITE_ONCE(q->drop_batch_size,
+			   max(1U, nla_get_u32(tb[TCA_FQ_CODEL_DROP_BATCH_SIZE])));
 
 	if (tb[TCA_FQ_CODEL_MEMORY_LIMIT])
-		q->memory_limit = min(1U << 31, nla_get_u32(tb[TCA_FQ_CODEL_MEMORY_LIMIT]));
+		WRITE_ONCE(q->memory_limit,
+			   min(1U << 31, nla_get_u32(tb[TCA_FQ_CODEL_MEMORY_LIMIT])));
 
 	while (sch->q.qlen > sch->limit ||
 	       q->memory_usage > q->memory_limit) {
-		struct sk_buff *skb = fq_codel_dequeue(sch);
+		struct sk_buff *skb = qdisc_dequeue_internal(sch, false);
 
 		q->cstats.drop_len += qdisc_pkt_len(skb);
 		rtnl_kfree_skbs(skb, skb);
@@ -522,6 +530,7 @@ init_failure:
 static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct fq_codel_sched_data *q = qdisc_priv(sch);
+	codel_time_t ce_threshold;
 	struct nlattr *opts;
 
 	opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
@@ -529,30 +538,33 @@ static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
 		goto nla_put_failure;
 
 	if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET,
-			codel_time_to_us(q->cparams.target)) ||
+			codel_time_to_us(READ_ONCE(q->cparams.target))) ||
 	    nla_put_u32(skb, TCA_FQ_CODEL_LIMIT,
-			sch->limit) ||
+			READ_ONCE(sch->limit)) ||
 	    nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL,
-			codel_time_to_us(q->cparams.interval)) ||
+			codel_time_to_us(READ_ONCE(q->cparams.interval))) ||
 	    nla_put_u32(skb, TCA_FQ_CODEL_ECN,
-			q->cparams.ecn) ||
+			READ_ONCE(q->cparams.ecn)) ||
 	    nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM,
-			q->quantum) ||
+			READ_ONCE(q->quantum)) ||
 	    nla_put_u32(skb, TCA_FQ_CODEL_DROP_BATCH_SIZE,
-			q->drop_batch_size) ||
+			READ_ONCE(q->drop_batch_size)) ||
 	    nla_put_u32(skb, TCA_FQ_CODEL_MEMORY_LIMIT,
-			q->memory_limit) ||
+			READ_ONCE(q->memory_limit)) ||
 	    nla_put_u32(skb, TCA_FQ_CODEL_FLOWS,
-			q->flows_cnt))
+			READ_ONCE(q->flows_cnt)))
 		goto nla_put_failure;
 
-	if (q->cparams.ce_threshold != CODEL_DISABLED_THRESHOLD) {
+	ce_threshold = READ_ONCE(q->cparams.ce_threshold);
+	if (ce_threshold != CODEL_DISABLED_THRESHOLD) {
 		if (nla_put_u32(skb, TCA_FQ_CODEL_CE_THRESHOLD,
-				codel_time_to_us(q->cparams.ce_threshold)))
+				codel_time_to_us(ce_threshold)))
 			goto nla_put_failure;
-		if (nla_put_u8(skb, TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR, q->cparams.ce_threshold_selector))
+		if (nla_put_u8(skb, TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR,
+			       READ_ONCE(q->cparams.ce_threshold_selector)))
 			goto nla_put_failure;
-		if (nla_put_u8(skb, TCA_FQ_CODEL_CE_THRESHOLD_MASK, q->cparams.ce_threshold_mask))
+		if (nla_put_u8(skb, TCA_FQ_CODEL_CE_THRESHOLD_MASK,
+			       READ_ONCE(q->cparams.ce_threshold_mask)))
 			goto nla_put_failure;
 	}