[PATCH 44/48] libertas: Move actual transmission to main thread
David Woodhouse
dwmw2 at infradead.org
Mon Dec 10 10:46:20 EST 2007
Date: Sun, 9 Dec 2007 23:54:27 -0500
The locking issues with TX, especially TX from multiple netdevs, get
_so_ much easier if you do it like this.
Signed-off-by: David Woodhouse <dwmw2 at infradead.org>
---
drivers/net/wireless/libertas/dev.h | 5 +-
drivers/net/wireless/libertas/main.c | 24 ++++++++
drivers/net/wireless/libertas/tx.c | 103 ++++++++++++++--------------------
3 files changed, 71 insertions(+), 61 deletions(-)
diff --git a/drivers/net/wireless/libertas/dev.h b/drivers/net/wireless/libertas/dev.h
index 04cf33d..4681405 100644
--- a/drivers/net/wireless/libertas/dev.h
+++ b/drivers/net/wireless/libertas/dev.h
@@ -164,7 +164,10 @@ struct lbs_private {
struct mutex lock;
- u8 tmptxbuf[LBS_UPLD_SIZE];
+ /* TX packet ready to be sent... */
+ int tx_pending_len; /* -1 while building packet */
+
+ u8 tx_pending_buf[LBS_UPLD_SIZE];
/* protected by hard_start_xmit serialization */
/** command-related variables */
diff --git a/drivers/net/wireless/libertas/main.c b/drivers/net/wireless/libertas/main.c
index 42b64b5..f16c93b 100644
--- a/drivers/net/wireless/libertas/main.c
+++ b/drivers/net/wireless/libertas/main.c
@@ -739,6 +739,8 @@ static int lbs_thread(void *data)
shouldsleep = 0; /* Interrupt pending. Deal with it now */
else if (priv->dnld_sent)
shouldsleep = 1; /* Something is en route to the device already */
+ else if (priv->tx_pending_len > 0)
+ shouldsleep = 0; /* We've a packet to send */
else if (priv->cur_cmd)
shouldsleep = 1; /* Can't send a command; one already running */
else if (!list_empty(&priv->cmdpendingq))
@@ -852,6 +854,28 @@ static int lbs_thread(void *data)
*/
if (!list_empty(&priv->cmdpendingq))
wake_up_all(&priv->cmd_pending);
+
+ spin_lock_irq(&priv->driver_lock);
+ if (!priv->dnld_sent && priv->tx_pending_len > 0) {
+ int ret = priv->hw_host_to_card(priv, MVMS_DAT,
+ priv->tx_pending_buf,
+ priv->tx_pending_len);
+ if (ret) {
+ lbs_deb_tx("host_to_card failed %d\n", ret);
+ priv->dnld_sent = DNLD_RES_RECEIVED;
+ }
+ priv->tx_pending_len = 0;
+ if (!priv->currenttxskb) {
+ /* We can wake the queues immediately if we aren't
+ waiting for TX feedback */
+ if (priv->connect_status == LBS_CONNECTED)
+ netif_wake_queue(priv->dev);
+ if (priv->mesh_dev &&
+ priv->mesh_connect_status == LBS_CONNECTED)
+ netif_wake_queue(priv->mesh_dev);
+ }
+ }
+ spin_unlock_irq(&priv->driver_lock);
}
del_timer(&priv->command_timer);
diff --git a/drivers/net/wireless/libertas/tx.c b/drivers/net/wireless/libertas/tx.c
index 300aa05..e2141f0 100644
--- a/drivers/net/wireless/libertas/tx.c
+++ b/drivers/net/wireless/libertas/tx.c
@@ -67,39 +67,45 @@ int lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
lbs_deb_enter(LBS_DEB_TX);
- ret = NETDEV_TX_BUSY;
-
- if (priv->dnld_sent) {
- lbs_pr_alert( "TX error: dnld_sent = %d, not sending\n",
- priv->dnld_sent);
- goto done;
- }
-
- if (priv->currenttxskb) {
- lbs_pr_err("%s while TX skb pending\n", __func__);
- goto done;
- }
+ ret = NETDEV_TX_OK;
- if ((priv->psstate == PS_STATE_SLEEP) ||
- (priv->psstate == PS_STATE_PRE_SLEEP)) {
- lbs_pr_alert("TX error: packet xmit in %ssleep mode\n",
- priv->psstate == PS_STATE_SLEEP?"":"pre-");
- goto done;
- }
+ /* We need to protect against the queues being restarted before
+ we get round to stopping them */
+ spin_lock_irqsave(&priv->driver_lock, flags);
if (priv->surpriseremoved)
- goto drop;
+ goto free;
if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
skb->len, MRVDRV_ETH_TX_PACKET_BUFFER_SIZE);
/* We'll never manage to send this one; drop it and return 'OK' */
- goto drop;
+
+ priv->stats.tx_dropped++;
+ priv->stats.tx_errors++;
+ goto free;
+ }
+
+
+ netif_stop_queue(priv->dev);
+ if (priv->mesh_dev)
+ netif_stop_queue(priv->mesh_dev);
+
+ if (priv->tx_pending_len) {
+ /* This can happen if packets come in on the mesh and eth
+ device simultaneously -- there's no mutual exclusion on
+ hard_start_xmit() calls between devices. */
+ lbs_deb_tx("Packet on %s while busy\n", dev->name);
+ ret = NETDEV_TX_BUSY;
+ goto unlock;
}
+ priv->tx_pending_len = -1;
+ spin_unlock_irqrestore(&priv->driver_lock, flags);
+
lbs_deb_hex(LBS_DEB_TX, "TX Data", skb->data, min_t(unsigned int, skb->len, 100));
- txpd = (void *)priv->tmptxbuf;
+ txpd = (void *)priv->tx_pending_buf;
memset(txpd, 0, sizeof(struct txpd));
p802x_hdr = skb->data;
@@ -134,54 +140,31 @@ int lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
- /* We need to protect against the queues being restarted before
- we get round to stopping them */
spin_lock_irqsave(&priv->driver_lock, flags);
+ priv->tx_pending_len = pkt_len + sizeof(struct txpd);
- ret = priv->hw_host_to_card(priv, MVMS_DAT, priv->tmptxbuf,
- pkt_len + sizeof(struct txpd));
-
- if (!ret) {
- lbs_deb_tx("%s succeeds\n", __func__);
-
- /* Stop processing outgoing pkts before submitting */
- netif_stop_queue(priv->dev);
- if (priv->mesh_dev)
- netif_stop_queue(priv->mesh_dev);
-
- priv->stats.tx_packets++;
- priv->stats.tx_bytes += skb->len;
-
- dev->trans_start = jiffies;
+ lbs_deb_tx("%s lined up packet\n", __func__);
- if (priv->monitormode != LBS_MONITOR_OFF) {
- /* Keep the skb to echo it back once Tx feedback is
- received from FW */
- skb_orphan(skb);
+ priv->stats.tx_packets++;
+ priv->stats.tx_bytes += skb->len;
- /* Keep the skb around for when we get feedback */
- priv->currenttxskb = skb;
- } else
- dev_kfree_skb_any(skb);
-
- }
-
- spin_unlock_irqrestore(&priv->driver_lock, flags);
+ dev->trans_start = jiffies;
- if (ret) {
- lbs_deb_tx("tx err: hw_host_to_card returned 0x%X\n", ret);
-drop:
- priv->stats.tx_dropped++;
- priv->stats.tx_errors++;
+ if (priv->monitormode != LBS_MONITOR_OFF) {
+ /* Keep the skb to echo it back once Tx feedback is
+ received from FW */
+ skb_orphan(skb);
+ /* Keep the skb around for when we get feedback */
+ priv->currenttxskb = skb;
+ } else {
+ free:
dev_kfree_skb_any(skb);
}
+ unlock:
+ spin_unlock_irqrestore(&priv->driver_lock, flags);
+ wake_up(&priv->waitq);
- /* Even if we dropped the packet, return OK. Otherwise the
- packet gets requeued. */
- ret = NETDEV_TX_OK;
-
-done:
lbs_deb_leave_args(LBS_DEB_TX, "ret %d", ret);
return ret;
}
--
1.5.3.4
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