mac80211: Re-structure aqm debugfs output and keep CoDel stats per txq

Currently the 'aqm' stats in mac80211 only keeps overlimit drop stats,
not CoDel stats. This moves the CoDel stats into the txqi structure to
keep them per txq in order to show them in debugfs.

In addition, the aqm debugfs output is restructured by splitting it up
into three files: One global per phy, one per netdev and one per
station, in the appropriate directories. The files are all called aqm,
and are only created if the driver supports the wake_tx_queue op (rather
than emitting an error on open as previously).

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 52 insertions, 0 deletions

diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c
index fd334133ff45..fb2693582e40 100644
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -133,6 +133,55 @@ static ssize_t sta_last_seq_ctrl_read(struct file *file, char __user *userbuf,
 }
 STA_OPS(last_seq_ctrl);
 
+#define AQM_TXQ_ENTRY_LEN 130
+
+static ssize_t sta_aqm_read(struct file *file, char __user *userbuf,
+			size_t count, loff_t *ppos)
+{
+	struct sta_info *sta = file->private_data;
+	struct ieee80211_local *local = sta->local;
+	size_t bufsz = AQM_TXQ_ENTRY_LEN*(IEEE80211_NUM_TIDS+1);
+	char *buf = kzalloc(bufsz, GFP_KERNEL), *p = buf;
+	struct txq_info *txqi;
+	ssize_t rv;
+	int i;
+
+	if (!buf)
+		return -ENOMEM;
+
+	spin_lock_bh(&local->fq.lock);
+	rcu_read_lock();
+
+	p += scnprintf(p,
+		       bufsz+buf-p,
+		       "tid ac backlog-bytes backlog-packets new-flows drops marks overlimit collisions tx-bytes tx-packets\n");
+
+	for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
+		txqi = to_txq_info(sta->sta.txq[i]);
+		p += scnprintf(p, bufsz+buf-p,
+			       "%d %d %u %u %u %u %u %u %u %u %u\n",
+			       txqi->txq.tid,
+			       txqi->txq.ac,
+			       txqi->tin.backlog_bytes,
+			       txqi->tin.backlog_packets,
+			       txqi->tin.flows,
+			       txqi->cstats.drop_count,
+			       txqi->cstats.ecn_mark,
+			       txqi->tin.overlimit,
+			       txqi->tin.collisions,
+			       txqi->tin.tx_bytes,
+			       txqi->tin.tx_packets);
+	}
+
+	rcu_read_unlock();
+	spin_unlock_bh(&local->fq.lock);
+
+	rv = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+	kfree(buf);
+	return rv;
+}
+STA_OPS(aqm);
+
 static ssize_t sta_agg_status_read(struct file *file, char __user *userbuf,
 					size_t count, loff_t *ppos)
 {
@@ -478,6 +527,9 @@ void ieee80211_sta_debugfs_add(struct sta_info *sta)
 	DEBUGFS_ADD_COUNTER(rx_fragments, rx_stats.fragments);
 	DEBUGFS_ADD_COUNTER(tx_filtered, status_stats.filtered);
 
+	if (local->ops->wake_tx_queue)
+		DEBUGFS_ADD(aqm);
+
 	if (sizeof(sta->driver_buffered_tids) == sizeof(u32))
 		debugfs_create_x32("driver_buffered_tids", 0400,
 				   sta->debugfs_dir,