From: Abhijeet Kolekar <abhijeet.kolekar@xxxxxxxxx>
Port "iwlcore: Allow skb allocation from tasklet" to 3945
commit c8881170b7ce9897a7b9087d37ca3f281b347707
Author: Mohamed Abbas <mohamed.abbas@xxxxxxxxx>
Date: Fri May 22 11:01:51 2009 -0700
iwlcore: Allow skb allocation from tasklet.
If RX queue becomes empty then we need to restock the queue from tasklet to prevent
ucode from starving. A caller to iwl_rx_allocate will decide if allocated buffer should
come from GFP_ATOMIC or GFP_KERNEL.
Signed-off-by: Abhijeet Kolekar <abhijeet.kolekar@xxxxxxxxx>
Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
drivers/net/wireless/iwlwifi/iwl3945-base.c | 32 +++++++++++++++++++++------
1 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
index 745eaae..92fa1a3 100644
--- a/drivers/net/wireless/iwlwifi/iwl3945-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c
@@ -1176,7 +1176,7 @@ static int iwl3945_rx_queue_restock(struct iwl_priv *priv)
/* If we've added more space for the firmware to place data, tell it.
* Increment device's write pointer in multiples of 8. */
- if ((write != (rxq->write & ~0x7))
+ if ((rxq->write_actual != (rxq->write & ~0x7))
|| (abs(rxq->write - rxq->read) > 7)) {
spin_lock_irqsave(&rxq->lock, flags);
rxq->need_update = 1;
@@ -1197,7 +1197,7 @@ static int iwl3945_rx_queue_restock(struct iwl_priv *priv)
* Also restock the Rx queue via iwl3945_rx_queue_restock.
* This is called as a scheduled work item (except for during initialization)
*/
-static void iwl3945_rx_allocate(struct iwl_priv *priv)
+static void iwl3945_rx_allocate(struct iwl_priv *priv, gfp_t priority)
{
struct iwl_rx_queue *rxq = &priv->rxq;
struct list_head *element;
@@ -1220,7 +1220,7 @@ static void iwl3945_rx_allocate(struct iwl_priv *priv)
/* Alloc a new receive buffer */
rxb->skb =
alloc_skb(priv->hw_params.rx_buf_size,
- GFP_KERNEL);
+ priority);
if (!rxb->skb) {
if (net_ratelimit())
IWL_CRIT(priv, ": Can not allocate SKB buffers\n");
@@ -1279,6 +1279,7 @@ void iwl3945_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
* not restocked the Rx queue with fresh buffers */
rxq->read = rxq->write = 0;
rxq->free_count = 0;
+ rxq->write_actual = 0;
spin_unlock_irqrestore(&rxq->lock, flags);
}
@@ -1287,13 +1288,21 @@ void iwl3945_rx_replenish(void *data)
struct iwl_priv *priv = data;
unsigned long flags;
- iwl3945_rx_allocate(priv);
+ iwl3945_rx_allocate(priv, GFP_KERNEL);
spin_lock_irqsave(&priv->lock, flags);
iwl3945_rx_queue_restock(priv);
spin_unlock_irqrestore(&priv->lock, flags);
}
+static void iwl3945_rx_replenish_now(struct iwl_priv *priv)
+{
+ iwl3945_rx_allocate(priv, GFP_ATOMIC);
+
+ iwl3945_rx_queue_restock(priv);
+}
+
+
/* Assumes that the skb field of the buffers in 'pool' is kept accurate.
* If an SKB has been detached, the POOL needs to have its SKB set to NULL
* This free routine walks the list of POOL entries and if SKB is set to
@@ -1416,13 +1425,19 @@ static void iwl3945_rx_handle(struct iwl_priv *priv)
unsigned long flags;
u8 fill_rx = 0;
u32 count = 8;
+ int total_empty = 0;
/* uCode's read index (stored in shared DRAM) indicates the last Rx
* buffer that the driver may process (last buffer filled by ucode). */
r = le16_to_cpu(rxq->rb_stts->closed_rb_num) & 0x0FFF;
i = rxq->read;
- if (iwl_rx_queue_space(rxq) > (RX_QUEUE_SIZE / 2))
+ /* calculate total frames need to be restock after handling RX */
+ total_empty = r - priv->rxq.write_actual;
+ if (total_empty < 0)
+ total_empty += RX_QUEUE_SIZE;
+
+ if (total_empty > (RX_QUEUE_SIZE / 2))
fill_rx = 1;
/* Rx interrupt, but nothing sent from uCode */
if (i == r)
@@ -1499,7 +1514,7 @@ static void iwl3945_rx_handle(struct iwl_priv *priv)
count++;
if (count >= 8) {
priv->rxq.read = i;
- iwl3945_rx_queue_restock(priv);
+ iwl3945_rx_replenish_now(priv);
count = 0;
}
}
@@ -1507,7 +1522,10 @@ static void iwl3945_rx_handle(struct iwl_priv *priv)
/* Backtrack one entry */
priv->rxq.read = i;
- iwl3945_rx_queue_restock(priv);
+ if (fill_rx)
+ iwl3945_rx_replenish_now(priv);
+ else
+ iwl3945_rx_queue_restock(priv);
}
/* call this function to flush any scheduled tasklet */
--
1.5.6.3
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