p54: move statistic timer update routine into a workqueue

This patch moves a good chunk of code from the former statistic update
timer routine into a workqueue, which is kindly provided by mac80211.

Also as a nice side-effect we can lay the foundation for other
essential housekeeping features we want to do in the future.
e.g:
 - drain the (clogged) tx_queue.
 - initiate bursts.

Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/p54/p54.h b/drivers/net/wireless/p54/p54.h
index d2dbb9e..23b80ef 100644 (file)
--- a/drivers/net/wireless/p54/p54.h
+++ b/drivers/net/wireless/p54/p54.h
@@ -71,6 +71,7 @@ struct p54_edcf_queue_param {
 #define FW_LM20 0x4c4d3230
 
 struct p54_common {
+       struct ieee80211_hw *hw;
        u32 rx_start;
        u32 rx_end;
        struct sk_buff_head tx_queue;
@@ -106,9 +107,7 @@ struct p54_common {
        struct ieee80211_tx_queue_stats tx_stats[8];
        struct p54_edcf_queue_param qos_params[8];
        struct ieee80211_low_level_stats stats;
-       struct timer_list stats_timer;
-       struct completion stats_comp;
-       struct sk_buff *cached_stats;
+       struct delayed_work work;
        struct sk_buff *cached_beacon;
        int noise;
        void *eeprom;

diff --git a/drivers/net/wireless/p54/p54common.c b/drivers/net/wireless/p54/p54common.c
index a4e99b0..36310f8 100644 (file)
--- a/drivers/net/wireless/p54/p54common.c
+++ b/drivers/net/wireless/p54/p54common.c
@@ -589,6 +589,9 @@ static int p54_rx_data(struct ieee80211_hw *dev, struct sk_buff *skb)
 
        ieee80211_rx_irqsafe(dev, skb, &rx_status);
 
+       queue_delayed_work(dev->workqueue, &priv->work,
+                          msecs_to_jiffies(P54_STATISTICS_UPDATE));
+
        return -1;
 }
 
@@ -652,6 +655,27 @@ void p54_free_skb(struct ieee80211_hw *dev, struct sk_buff *skb)
 }
 EXPORT_SYMBOL_GPL(p54_free_skb);
 
+static struct sk_buff *p54_find_tx_entry(struct ieee80211_hw *dev,
+                                          __le32 req_id)
+{
+       struct p54_common *priv = dev->priv;
+       struct sk_buff *entry = priv->tx_queue.next;
+       unsigned long flags;
+
+       spin_lock_irqsave(&priv->tx_queue.lock, flags);
+       while (entry != (struct sk_buff *)&priv->tx_queue) {
+               struct p54_hdr *hdr = (struct p54_hdr *) entry->data;
+
+               if (hdr->req_id == req_id) {
+                       spin_unlock_irqrestore(&priv->tx_queue.lock, flags);
+                       return entry;
+               }
+               entry = entry->next;
+       }
+       spin_unlock_irqrestore(&priv->tx_queue.lock, flags);
+       return NULL;
+}
+
 static void p54_rx_frame_sent(struct ieee80211_hw *dev, struct sk_buff *skb)
 {
        struct p54_common *priv = dev->priv;
@@ -775,8 +799,12 @@ static void p54_rx_stats(struct ieee80211_hw *dev, struct sk_buff *skb)
        struct p54_common *priv = dev->priv;
        struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
        struct p54_statistics *stats = (struct p54_statistics *) hdr->data;
-       u32 tsf32 = le32_to_cpu(stats->tsf32);
+       u32 tsf32;
+
+       if (unlikely(priv->mode == NL80211_IFTYPE_UNSPECIFIED))
+               return ;
 
+       tsf32 = le32_to_cpu(stats->tsf32);
        if (tsf32 < priv->tsf_low32)
                priv->tsf_high32++;
        priv->tsf_low32 = tsf32;
@@ -786,9 +814,8 @@ static void p54_rx_stats(struct ieee80211_hw *dev, struct sk_buff *skb)
        priv->stats.dot11FCSErrorCount = le32_to_cpu(stats->rx_bad_fcs);
 
        priv->noise = p54_rssi_to_dbm(dev, le32_to_cpu(stats->noise));
-       complete(&priv->stats_comp);
 
-       mod_timer(&priv->stats_timer, jiffies + 5 * HZ);
+       p54_free_skb(dev, p54_find_tx_entry(dev, hdr->req_id));
 }
 
 static void p54_rx_trap(struct ieee80211_hw *dev, struct sk_buff *skb)
@@ -897,6 +924,8 @@ static int p54_assign_address(struct ieee80211_hw *dev, struct sk_buff *skb,
                 * have a few spare slots for control frames left.
                 */
                ieee80211_stop_queues(dev);
+               queue_delayed_work(dev->workqueue, &priv->work,
+                                  msecs_to_jiffies(P54_TX_TIMEOUT));
 
                if (unlikely(left == 32)) {
                        /*
@@ -1354,6 +1383,10 @@ static int p54_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
        if (unlikely(p54_assign_address(dev, skb, hdr, skb->len + tim_len)))
                goto err;
        priv->tx(dev, skb, 0);
+
+       queue_delayed_work(dev->workqueue, &priv->work,
+                          msecs_to_jiffies(P54_TX_FRAME_LIFETIME));
+
        return 0;
 
  err:
@@ -1579,20 +1612,6 @@ static int p54_set_edcf(struct ieee80211_hw *dev)
        return 0;
 }
 
-static int p54_init_stats(struct ieee80211_hw *dev)
-{
-       struct p54_common *priv = dev->priv;
-
-       priv->cached_stats = p54_alloc_skb(dev, P54_HDR_FLAG_CONTROL,
-                       sizeof(struct p54_hdr) + sizeof(struct p54_statistics),
-                       P54_CONTROL_TYPE_STAT_READBACK, GFP_KERNEL);
-       if (!priv->cached_stats)
-                       return -ENOMEM;
-
-       mod_timer(&priv->stats_timer, jiffies + HZ);
-       return 0;
-}
-
 static int p54_beacon_tim(struct sk_buff *skb)
 {
        /*
@@ -1686,9 +1705,6 @@ static int p54_start(struct ieee80211_hw *dev)
        err = p54_set_edcf(dev);
        if (err)
                goto out;
-       err = p54_init_stats(dev);
-       if (err)
-               goto out;
 
        memset(priv->bssid, ~0, ETH_ALEN);
        priv->mode = NL80211_IFTYPE_MONITOR;
@@ -1698,6 +1714,8 @@ static int p54_start(struct ieee80211_hw *dev)
                goto out;
        }
 
+       queue_delayed_work(dev->workqueue, &priv->work, 0);
+
 out:
        mutex_unlock(&priv->conf_mutex);
        return err;
@@ -1710,9 +1728,7 @@ static void p54_stop(struct ieee80211_hw *dev)
 
        mutex_lock(&priv->conf_mutex);
        priv->mode = NL80211_IFTYPE_UNSPECIFIED;
-       del_timer(&priv->stats_timer);
-       p54_free_skb(dev, priv->cached_stats);
-       priv->cached_stats = NULL;
+       cancel_delayed_work_sync(&priv->work);
        if (priv->cached_beacon)
                p54_tx_cancel(dev, priv->cached_beacon);
 
@@ -1889,14 +1905,29 @@ static int p54_init_xbow_synth(struct ieee80211_hw *dev)
        return 0;
 }
 
-static void p54_statistics_timer(unsigned long data)
+static void p54_work(struct work_struct *work)
 {
-       struct ieee80211_hw *dev = (struct ieee80211_hw *) data;
-       struct p54_common *priv = dev->priv;
+       struct p54_common *priv = container_of(work, struct p54_common,
+                                              work.work);
+       struct ieee80211_hw *dev = priv->hw;
+       struct sk_buff *skb;
+
+       if (unlikely(priv->mode == NL80211_IFTYPE_UNSPECIFIED))
+               return ;
+
+       /*
+        * TODO: walk through tx_queue and do the following tasks
+        *      1. initiate bursts.
+        *      2. cancel stuck frames / reset the device if necessary.
+        */
 
-       BUG_ON(!priv->cached_stats);
+       skb = p54_alloc_skb(dev, P54_HDR_FLAG_CONTROL, sizeof(struct p54_hdr) +
+                           sizeof(struct p54_statistics),
+                           P54_CONTROL_TYPE_STAT_READBACK, GFP_KERNEL);
+       if (!skb)
+               return ;
 
-       priv->tx(dev, priv->cached_stats, 0);
+       priv->tx(dev, skb, 0);
 }
 
 static int p54_get_stats(struct ieee80211_hw *dev,
@@ -1904,17 +1935,7 @@ static int p54_get_stats(struct ieee80211_hw *dev,
 {
        struct p54_common *priv = dev->priv;
 
-       del_timer(&priv->stats_timer);
-       p54_statistics_timer((unsigned long)dev);
-
-       if (!wait_for_completion_interruptible_timeout(&priv->stats_comp, HZ)) {
-               printk(KERN_ERR "%s: device does not respond!\n",
-                       wiphy_name(dev->wiphy));
-               return -EBUSY;
-       }
-
        memcpy(stats, &priv->stats, sizeof(*stats));
-
        return 0;
 }
 
@@ -2072,6 +2093,7 @@ struct ieee80211_hw *p54_init_common(size_t priv_data_len)
                return NULL;
 
        priv = dev->priv;
+       priv->hw = dev;
        priv->mode = NL80211_IFTYPE_UNSPECIFIED;
        priv->basic_rate_mask = 0x15f;
        skb_queue_head_init(&priv->tx_queue);
@@ -2107,9 +2129,7 @@ struct ieee80211_hw *p54_init_common(size_t priv_data_len)
 
        mutex_init(&priv->conf_mutex);
        init_completion(&priv->eeprom_comp);
-       init_completion(&priv->stats_comp);
-       setup_timer(&priv->stats_timer, p54_statistics_timer,
-               (unsigned long)dev);
+       INIT_DELAYED_WORK(&priv->work, p54_work);
 
        return dev;
 }
@@ -2118,8 +2138,6 @@ EXPORT_SYMBOL_GPL(p54_init_common);
 void p54_free_common(struct ieee80211_hw *dev)
 {
        struct p54_common *priv = dev->priv;
-       del_timer(&priv->stats_timer);
-       kfree_skb(priv->cached_stats);
        kfree(priv->iq_autocal);
        kfree(priv->output_limit);
        kfree(priv->curve_data);

diff --git a/drivers/net/wireless/p54/p54common.h b/drivers/net/wireless/p54/p54common.h
index 5a68fda..06e1643 100644 (file)
--- a/drivers/net/wireless/p54/p54common.h
+++ b/drivers/net/wireless/p54/p54common.h
@@ -355,6 +355,11 @@ struct p54_tx_data {
        u8 align[0];
 } __attribute__ ((packed));
 
+/* unit is ms */
+#define P54_TX_FRAME_LIFETIME 2000
+#define P54_TX_TIMEOUT 4000
+#define P54_STATISTICS_UPDATE 5000
+
 #define P54_FILTER_TYPE_NONE           0
 #define P54_FILTER_TYPE_STATION                BIT(0)
 #define P54_FILTER_TYPE_IBSS           BIT(1)