1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
From: Alexander Wetzel <alexander@wetzel-home.de>
Date: Sun, 9 Oct 2022 18:30:38 +0200
Subject: [PATCH] wifi: mac80211: add internal handler for wake_tx_queue
Start to align the TX handling to only use internal TX queues (iTXQs):
Provide a handler for drivers not having a custom wake_tx_queue
callback and update the documentation.
Signed-off-by: Alexander Wetzel <alexander@wetzel-home.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -89,15 +89,13 @@
/**
* DOC: mac80211 software tx queueing
*
- * mac80211 provides an optional intermediate queueing implementation designed
- * to allow the driver to keep hardware queues short and provide some fairness
- * between different stations/interfaces.
- * In this model, the driver pulls data frames from the mac80211 queue instead
- * of letting mac80211 push them via drv_tx().
- * Other frames (e.g. control or management) are still pushed using drv_tx().
+ * mac80211 uses an intermediate queueing implementation, designed to allow the
+ * driver to keep hardware queues short and to provide some fairness between
+ * different stations/interfaces.
*
- * Drivers indicate that they use this model by implementing the .wake_tx_queue
- * driver operation.
+ * Drivers must provide the .wake_tx_queue driver operation by either
+ * linking it to ieee80211_handle_wake_tx_queue() or implementing a custom
+ * handler.
*
* Intermediate queues (struct ieee80211_txq) are kept per-sta per-tid, with
* another per-sta for non-data/non-mgmt and bufferable management frames, and
@@ -106,9 +104,12 @@
* The driver is expected to initialize its private per-queue data for stations
* and interfaces in the .add_interface and .sta_add ops.
*
- * The driver can't access the queue directly. To dequeue a frame from a
- * txq, it calls ieee80211_tx_dequeue(). Whenever mac80211 adds a new frame to a
- * queue, it calls the .wake_tx_queue driver op.
+ * The driver can't access the internal TX queues (iTXQs) directly.
+ * Whenever mac80211 adds a new frame to a queue, it calls the .wake_tx_queue
+ * driver op.
+ * Drivers implementing a custom .wake_tx_queue op can get them by calling
+ * ieee80211_tx_dequeue(). Drivers using ieee80211_handle_wake_tx_queue() will
+ * simply get the individual frames pushed via the .tx driver operation.
*
* Drivers can optionally delegate responsibility for scheduling queues to
* mac80211, to take advantage of airtime fairness accounting. In this case, to
@@ -1826,7 +1827,7 @@ struct ieee80211_vif_cfg {
* for this interface.
* @drv_priv: data area for driver use, will always be aligned to
* sizeof(void \*).
- * @txq: the multicast data TX queue (if driver uses the TXQ abstraction)
+ * @txq: the multicast data TX queue
* @txqs_stopped: per AC flag to indicate that intermediate TXQs are stopped,
* protected by fq->lock.
* @offload_flags: 802.3 -> 802.11 enapsulation offload flags, see
@@ -2252,8 +2253,8 @@ struct ieee80211_link_sta {
* For non MLO STA it will point to the deflink data. For MLO STA
* ieee80211_sta_recalc_aggregates() must be called to update it.
* @support_p2p_ps: indicates whether the STA supports P2P PS mechanism or not.
- * @txq: per-TID data TX queues (if driver uses the TXQ abstraction); note that
- * the last entry (%IEEE80211_NUM_TIDS) is used for non-data frames
+ * @txq: per-TID data TX queues; note that the last entry (%IEEE80211_NUM_TIDS)
+ * is used for non-data frames
* @deflink: This holds the default link STA information, for non MLO STA all link
* specific STA information is accessed through @deflink or through
* link[0] which points to address of @deflink. For MLO Link STA
@@ -5691,7 +5692,7 @@ void ieee80211_key_replay(struct ieee802
* @hw: pointer as obtained from ieee80211_alloc_hw().
* @queue: queue number (counted from zero).
*
- * Drivers should use this function instead of netif_wake_queue.
+ * Drivers must use this function instead of netif_wake_queue.
*/
void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue);
@@ -5700,7 +5701,7 @@ void ieee80211_wake_queue(struct ieee802
* @hw: pointer as obtained from ieee80211_alloc_hw().
* @queue: queue number (counted from zero).
*
- * Drivers should use this function instead of netif_stop_queue.
+ * Drivers must use this function instead of netif_stop_queue.
*/
void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue);
@@ -5709,7 +5710,7 @@ void ieee80211_stop_queue(struct ieee802
* @hw: pointer as obtained from ieee80211_alloc_hw().
* @queue: queue number (counted from zero).
*
- * Drivers should use this function instead of netif_stop_queue.
+ * Drivers must use this function instead of netif_queue_stopped.
*
* Return: %true if the queue is stopped. %false otherwise.
*/
@@ -5720,7 +5721,7 @@ int ieee80211_queue_stopped(struct ieee8
* ieee80211_stop_queues - stop all queues
* @hw: pointer as obtained from ieee80211_alloc_hw().
*
- * Drivers should use this function instead of netif_stop_queue.
+ * Drivers must use this function instead of netif_tx_stop_all_queues.
*/
void ieee80211_stop_queues(struct ieee80211_hw *hw);
@@ -5728,7 +5729,7 @@ void ieee80211_stop_queues(struct ieee80
* ieee80211_wake_queues - wake all queues
* @hw: pointer as obtained from ieee80211_alloc_hw().
*
- * Drivers should use this function instead of netif_wake_queue.
+ * Drivers must use this function instead of netif_tx_wake_all_queues.
*/
void ieee80211_wake_queues(struct ieee80211_hw *hw);
@@ -6950,6 +6951,18 @@ static inline struct sk_buff *ieee80211_
}
/**
+ * ieee80211_handle_wake_tx_queue - mac80211 handler for wake_tx_queue callback
+ *
+ * @hw: pointer as obtained from wake_tx_queue() callback().
+ * @txq: pointer as obtained from wake_tx_queue() callback().
+ *
+ * Drivers can use this function for the mandatory mac80211 wake_tx_queue
+ * callback in struct ieee80211_ops. They should not call this function.
+ */
+void ieee80211_handle_wake_tx_queue(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq);
+
+/**
* ieee80211_next_txq - get next tx queue to pull packets from
*
* @hw: pointer as obtained from ieee80211_alloc_hw()
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -288,6 +288,52 @@ __le16 ieee80211_ctstoself_duration(stru
}
EXPORT_SYMBOL(ieee80211_ctstoself_duration);
+static void wake_tx_push_queue(struct ieee80211_local *local,
+ struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_txq *queue)
+{
+ int q = sdata->vif.hw_queue[queue->ac];
+ struct ieee80211_tx_control control = {
+ .sta = queue->sta,
+ };
+ struct sk_buff *skb;
+ unsigned long flags;
+ bool q_stopped;
+
+ while (1) {
+ spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+ q_stopped = local->queue_stop_reasons[q];
+ spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+
+ if (q_stopped)
+ break;
+
+ skb = ieee80211_tx_dequeue(&local->hw, queue);
+ if (!skb)
+ break;
+
+ drv_tx(local, &control, skb);
+ }
+}
+
+/* wake_tx_queue handler for driver not implementing a custom one*/
+void ieee80211_handle_wake_tx_queue(struct ieee80211_hw *hw,
+ struct ieee80211_txq *txq)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->vif);
+ struct ieee80211_txq *queue;
+
+ /* Use ieee80211_next_txq() for airtime fairness accounting */
+ ieee80211_txq_schedule_start(hw, txq->ac);
+ while ((queue = ieee80211_next_txq(hw, txq->ac))) {
+ wake_tx_push_queue(local, sdata, queue);
+ ieee80211_return_txq(hw, queue, false);
+ }
+ ieee80211_txq_schedule_end(hw, txq->ac);
+}
+EXPORT_SYMBOL(ieee80211_handle_wake_tx_queue);
+
static void __ieee80211_wake_txqs(struct ieee80211_sub_if_data *sdata, int ac)
{
struct ieee80211_local *local = sdata->local;
|