From 4752c93c30441f98f7ed723001b1a5e3e5619829 Mon Sep 17 00:00:00 2001 From: Mohamed Abbas Date: Fri, 22 May 2009 11:01:51 -0700 Subject: [PATCH] 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 Signed-off-by: Reinette Chatre Signed-off-by: John W. Linville --- drivers/net/wireless/iwlwifi/iwl-agn.c | 15 ++++++++++++--- drivers/net/wireless/iwlwifi/iwl-core.h | 3 ++- drivers/net/wireless/iwlwifi/iwl-dev.h | 1 + drivers/net/wireless/iwlwifi/iwl-rx.c | 25 +++++++++++++++++++------ 4 files changed, 34 insertions(+), 10 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c index fa24b019c62c..be1058bdc4c5 100644 --- a/drivers/net/wireless/iwlwifi/iwl-agn.c +++ b/drivers/net/wireless/iwlwifi/iwl-agn.c @@ -831,6 +831,7 @@ void iwl_rx_handle(struct iwl_priv *priv) 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 @@ void iwl_rx_handle(struct iwl_priv *priv) 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 @@ void iwl_rx_handle(struct iwl_priv *priv) count++; if (count >= 8) { priv->rxq.read = i; - iwl_rx_queue_restock(priv); + iwl_rx_replenish_now(priv); count = 0; } } @@ -926,7 +932,10 @@ void iwl_rx_handle(struct iwl_priv *priv) /* 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 cbd87afbf9ae..87df1b767941 100644 --- a/drivers/net/wireless/iwlwifi/iwl-core.h +++ b/drivers/net/wireless/iwlwifi/iwl-core.h @@ -318,10 +318,11 @@ int iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, 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 2076742effdd..770cd1b062ff 100644 --- a/drivers/net/wireless/iwlwifi/iwl-dev.h +++ b/drivers/net/wireless/iwlwifi/iwl-dev.h @@ -382,6 +382,7 @@ struct iwl_rx_queue { 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 7a432829e79f..c845089701eb 100644 --- a/drivers/net/wireless/iwlwifi/iwl-rx.c +++ b/drivers/net/wireless/iwlwifi/iwl-rx.c @@ -145,12 +145,14 @@ int iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q) 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 @@ int iwl_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)) { spin_lock_irqsave(&rxq->lock, flags); rxq->need_update = 1; spin_unlock_irqrestore(&rxq->lock, flags); @@ -232,7 +234,7 @@ EXPORT_SYMBOL(iwl_rx_queue_restock); * 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 @@ void iwl_rx_allocate(struct iwl_priv *priv) /* 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 @@ void iwl_rx_replenish(struct iwl_priv *priv) { 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 @@ void iwl_rx_replenish(struct iwl_priv *priv) } 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 @@ int iwl_rx_queue_alloc(struct iwl_priv *priv) /* 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 @@ void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq) /* 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); } -- 2.39.5