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: Mohamed Abbas <mohamed.abbas@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index fa24b01..be1058b 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -831,6 +831,7 @@
unsigned long flags;
u8 fill_rx = 0;
u32 count = 8;
+ int total_empty;
/* uCode's read index (stored in shared DRAM) indicates the last Rx
* buffer that the driver may process (last buffer filled by ucode). */
@@ -841,7 +842,12 @@
if (i == r)
IWL_DEBUG_RX(priv, "r = %d, i = %d\n", r, i);
- 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;
while (i != r) {
@@ -918,7 +924,7 @@
count++;
if (count >= 8) {
priv->rxq.read = i;
- iwl_rx_queue_restock(priv);
+ iwl_rx_replenish_now(priv);
count = 0;
}
}
@@ -926,7 +932,10 @@
/* Backtrack one entry */
priv->rxq.read = i;
- iwl_rx_queue_restock(priv);
+ if (fill_rx)
+ iwl_rx_replenish_now(priv);
+ else
+ iwl_rx_queue_restock(priv);
}
/* call this function to flush any scheduled tasklet */
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index cbd87af..87df1b76 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -318,10 +318,11 @@
struct iwl_rx_queue *q);
void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq);
void iwl_rx_replenish(struct iwl_priv *priv);
+void iwl_rx_replenish_now(struct iwl_priv *priv);
int iwl_rx_init(struct iwl_priv *priv, struct iwl_rx_queue *rxq);
int iwl_rx_queue_restock(struct iwl_priv *priv);
int iwl_rx_queue_space(const struct iwl_rx_queue *q);
-void iwl_rx_allocate(struct iwl_priv *priv);
+void iwl_rx_allocate(struct iwl_priv *priv, gfp_t priority);
void iwl_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb);
int iwl_tx_queue_reclaim(struct iwl_priv *priv, int txq_id, int index);
/* Handlers */
diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index 2076742..770cd1b 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -382,6 +382,7 @@
u32 read;
u32 write;
u32 free_count;
+ u32 write_actual;
struct list_head rx_free;
struct list_head rx_used;
int need_update;
diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c
index 7a43282..c845089 100644
--- a/drivers/net/wireless/iwlwifi/iwl-rx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-rx.c
@@ -145,12 +145,14 @@
goto exit_unlock;
}
- iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write & ~0x7);
+ q->write_actual = (q->write & ~0x7);
+ iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual);
/* Else device is assumed to be awake */
} else {
/* Device expects a multiple of 8 */
- iwl_write32(priv, rx_wrt_ptr_reg, q->write & ~0x7);
+ q->write_actual = (q->write & ~0x7);
+ iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual);
}
q->need_update = 0;
@@ -212,7 +214,7 @@
/* 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)) {
spin_lock_irqsave(&rxq->lock, flags);
rxq->need_update = 1;
spin_unlock_irqrestore(&rxq->lock, flags);
@@ -232,7 +234,7 @@
* Also restock the Rx queue via iwl_rx_queue_restock.
* This is called as a scheduled work item (except for during initialization)
*/
-void iwl_rx_allocate(struct iwl_priv *priv)
+void iwl_rx_allocate(struct iwl_priv *priv, gfp_t priority)
{
struct iwl_rx_queue *rxq = &priv->rxq;
struct list_head *element;
@@ -254,7 +256,8 @@
/* Alloc a new receive buffer */
rxb->skb = alloc_skb(priv->hw_params.rx_buf_size + 256,
- GFP_KERNEL);
+ priority);
+
if (!rxb->skb) {
IWL_CRIT(priv, "Can not allocate SKB buffers\n");
/* We don't reschedule replenish work here -- we will
@@ -289,7 +292,7 @@
{
unsigned long flags;
- iwl_rx_allocate(priv);
+ iwl_rx_allocate(priv, GFP_KERNEL);
spin_lock_irqsave(&priv->lock, flags);
iwl_rx_queue_restock(priv);
@@ -297,6 +300,14 @@
}
EXPORT_SYMBOL(iwl_rx_replenish);
+void iwl_rx_replenish_now(struct iwl_priv *priv)
+{
+ iwl_rx_allocate(priv, GFP_ATOMIC);
+
+ iwl_rx_queue_restock(priv);
+}
+EXPORT_SYMBOL(iwl_rx_replenish_now);
+
/* 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
@@ -352,6 +363,7 @@
/* Set us so that we have processed and used all buffers, but have
* not restocked the Rx queue with fresh buffers */
rxq->read = rxq->write = 0;
+ rxq->write_actual = 0;
rxq->free_count = 0;
rxq->need_update = 0;
return 0;
@@ -390,6 +402,7 @@
/* Set us so that we have processed and used all buffers, but have
* not restocked the Rx queue with fresh buffers */
rxq->read = rxq->write = 0;
+ rxq->write_actual = 0;
rxq->free_count = 0;
spin_unlock_irqrestore(&rxq->lock, flags);
}