1 files changed, 124 insertions, 0 deletions
diff --git a/package/kernel/mac80211/patches/subsys/354-mac80211-calculate-hash-for-fq-without-holding-fq-lo.patch b/package/kernel/mac80211/patches/subsys/354-mac80211-calculate-hash-for-fq-without-holding-fq-lo.patch
new file mode 100644
index 0000000000..2b6d8ab525
--- /dev/null
+++ b/package/kernel/mac80211/patches/subsys/354-mac80211-calculate-hash-for-fq-without-holding-fq-lo.patch
@@ -0,0 +1,124 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sat, 16 Mar 2019 17:57:38 +0100
+Subject: [PATCH] mac80211: calculate hash for fq without holding fq->lock
+ in itxq enqueue
+
+Reduces lock contention on enqueue/dequeue of iTXQ packets
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/include/net/fq_impl.h
++++ b/include/net/fq_impl.h
+@@ -107,21 +107,23 @@ begin:
+ 	return skb;
+ }
+ 
++static u32 fq_flow_idx(struct fq *fq, struct sk_buff *skb)
++{
++	u32 hash = skb_get_hash_perturb(skb, fq->perturbation);
++
++	return reciprocal_scale(hash, fq->flows_cnt);
++}
++
+ static struct fq_flow *fq_flow_classify(struct fq *fq,
+-					struct fq_tin *tin,
++					struct fq_tin *tin, u32 idx,
+ 					struct sk_buff *skb,
+ 					fq_flow_get_default_t get_default_func)
+ {
+ 	struct fq_flow *flow;
+-	u32 hash;
+-	u32 idx;
+ 
+ 	lockdep_assert_held(&fq->lock);
+ 
+-	hash = skb_get_hash_perturb(skb, fq->perturbation);
+-	idx = reciprocal_scale(hash, fq->flows_cnt);
+ 	flow = &fq->flows[idx];
+-
+ 	if (flow->tin && flow->tin != tin) {
+ 		flow = get_default_func(fq, tin, idx, skb);
+ 		tin->collisions++;
+@@ -153,7 +155,7 @@ static void fq_recalc_backlog(struct fq
+ }
+ 
+ static void fq_tin_enqueue(struct fq *fq,
+-			   struct fq_tin *tin,
++			   struct fq_tin *tin, u32 idx,
+ 			   struct sk_buff *skb,
+ 			   fq_skb_free_t free_func,
+ 			   fq_flow_get_default_t get_default_func)
+@@ -163,7 +165,7 @@ static void fq_tin_enqueue(struct fq *fq
+ 
+ 	lockdep_assert_held(&fq->lock);
+ 
+-	flow = fq_flow_classify(fq, tin, skb, get_default_func);
++	flow = fq_flow_classify(fq, tin, idx, skb, get_default_func);
+ 
+ 	flow->tin = tin;
+ 	flow->backlog += skb->len;
+--- a/net/mac80211/tx.c
++++ b/net/mac80211/tx.c
+@@ -1390,11 +1390,15 @@ static void ieee80211_txq_enqueue(struct
+ {
+ 	struct fq *fq = &local->fq;
+ 	struct fq_tin *tin = &txqi->tin;
++	u32 flow_idx = fq_flow_idx(fq, skb);
+ 
+ 	ieee80211_set_skb_enqueue_time(skb);
+-	fq_tin_enqueue(fq, tin, skb,
++
++	spin_lock_bh(&fq->lock);
++	fq_tin_enqueue(fq, tin, flow_idx, skb,
+ 		       fq_skb_free_func,
+ 		       fq_flow_get_default_func);
++	spin_unlock_bh(&fq->lock);
+ }
+ 
+ static bool fq_vlan_filter_func(struct fq *fq, struct fq_tin *tin,
+@@ -1564,7 +1568,6 @@ static bool ieee80211_queue_skb(struct i
+ 				struct sta_info *sta,
+ 				struct sk_buff *skb)
+ {
+-	struct fq *fq = &local->fq;
+ 	struct ieee80211_vif *vif;
+ 	struct txq_info *txqi;
+ 
+@@ -1582,9 +1585,7 @@ static bool ieee80211_queue_skb(struct i
+ 	if (!txqi)
+ 		return false;
+ 
+-	spin_lock_bh(&fq->lock);
+ 	ieee80211_txq_enqueue(local, txqi, skb);
+-	spin_unlock_bh(&fq->lock);
+ 
+ 	schedule_and_wake_txq(local, txqi);
+ 
+@@ -3198,6 +3199,7 @@ static bool ieee80211_amsdu_aggregate(st
+ 	u8 max_subframes = sta->sta.max_amsdu_subframes;
+ 	int max_frags = local->hw.max_tx_fragments;
+ 	int max_amsdu_len = sta->sta.max_amsdu_len;
++	u32 flow_idx;
+ 	int orig_truesize;
+ 	__be16 len;
+ 	void *data;
+@@ -3220,6 +3222,8 @@ static bool ieee80211_amsdu_aggregate(st
+ 		max_amsdu_len = min_t(int, max_amsdu_len,
+ 				      sta->sta.max_rc_amsdu_len);
+ 
++	flow_idx = fq_flow_idx(fq, skb);
++
+ 	spin_lock_bh(&fq->lock);
+ 
+ 	/* TODO: Ideally aggregation should be done on dequeue to remain
+@@ -3227,7 +3231,8 @@ static bool ieee80211_amsdu_aggregate(st
+ 	 */
+ 
+ 	tin = &txqi->tin;
+-	flow = fq_flow_classify(fq, tin, skb, fq_flow_get_default_func);
++	flow = fq_flow_classify(fq, tin, flow_idx, skb,
++				fq_flow_get_default_func);
+ 	head = skb_peek_tail(&flow->queue);
+ 	if (!head)
+ 		goto unlock;