Commit 015c15e1 authored by Johannes Berg's avatar Johannes Berg Committed by John W. Linville
Browse files

iwlwifi: introduce per-queue locks 



Instead of (ab)using the sta_lock, make the
transport layer lock its own TX queue data
structures with a lock per queue. This also
unifies with the cmd queue lock.

Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarWey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 9451ca1a

drivers/net/wireless/iwlwifi/iwl-trans-pcie-int.h

+2 −0
Original line number Diff line number Diff line
@@ -169,6 +169,7 @@ struct iwl_queue { 
 * @meta: array of meta data for each command/tx buffer

 * @dma_addr_cmd: physical address of cmd/tx buffer array

 * @txb: array of per-TFD driver data

 * lock: queue lock

 * @time_stamp: time (in jiffies) of last read_ptr change

 * @need_update: indicates need to update read/write index

 * @sched_retry: indicates queue is high-throughput aggregation (HT AGG) enabled
@@ -187,6 +188,7 @@ struct iwl_tx_queue { 
	struct iwl_device_cmd **cmd;

	struct iwl_cmd_meta *meta;

	struct sk_buff **skbs;

	spinlock_t lock;

	unsigned long time_stamp;

	u8 need_update;

	u8 sched_retry;

drivers/net/wireless/iwlwifi/iwl-trans-pcie-tx.c

+12 −8
Original line number Diff line number Diff line
@@ -217,6 +217,8 @@ void iwlagn_txq_free_tfd(struct iwl_trans *trans, struct iwl_tx_queue *txq, 
{

	struct iwl_tfd *tfd_tmp = txq->tfds;



	lockdep_assert_held(&txq->lock);



	iwlagn_unmap_tfd(trans, &txq->meta[index], &tfd_tmp[index], dma_dir);



	/* free SKB */
@@ -621,7 +623,6 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) 
	struct iwl_device_cmd *out_cmd;

	struct iwl_cmd_meta *out_meta;

	dma_addr_t phys_addr;

	unsigned long flags;

	u32 idx;

	u16 copy_size, cmd_size;

	bool is_ct_kill = false;
@@ -680,10 +681,10 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) 
		return -EIO;

	}



	spin_lock_irqsave(&trans->hcmd_lock, flags);

	spin_lock_bh(&txq->lock);



	if (iwl_queue_space(q) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {

		spin_unlock_irqrestore(&trans->hcmd_lock, flags);

		spin_unlock_bh(&txq->lock);



		IWL_ERR(trans, "No space in command queue\n");

		is_ct_kill = iwl_check_for_ct_kill(priv(trans));
@@ -790,7 +791,7 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) 
	iwl_txq_update_write_ptr(trans, txq);



 out:

	spin_unlock_irqrestore(&trans->hcmd_lock, flags);

	spin_unlock_bh(&txq->lock);

	return idx;

}
@@ -809,6 +810,8 @@ static void iwl_hcmd_queue_reclaim(struct iwl_trans *trans, int txq_id, 
	struct iwl_queue *q = &txq->q;

	int nfreed = 0;



	lockdep_assert_held(&txq->lock);



	if ((idx >= q->n_bd) || (iwl_queue_used(q, idx) == 0)) {

		IWL_ERR(trans, "%s: Read index for DMA queue txq id (%d), "

			  "index %d is out of range [0-%d] %d %d.\n", __func__,
@@ -850,7 +853,6 @@ void iwl_tx_cmd_complete(struct iwl_trans *trans, struct iwl_rx_mem_buffer *rxb, 
	struct iwl_cmd_meta *meta;

	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	struct iwl_tx_queue *txq = &trans_pcie->txq[trans->shrd->cmd_queue];

	unsigned long flags;



	/* If a Tx command is being handled and it isn't in the actual

	 * command queue then there a command routing bug has been introduced
@@ -864,6 +866,8 @@ void iwl_tx_cmd_complete(struct iwl_trans *trans, struct iwl_rx_mem_buffer *rxb, 
		return;

	}



	spin_lock(&txq->lock);



	cmd_index = get_cmd_index(&txq->q, index);

	cmd = txq->cmd[cmd_index];

	meta = &txq->meta[cmd_index];
@@ -880,8 +884,6 @@ void iwl_tx_cmd_complete(struct iwl_trans *trans, struct iwl_rx_mem_buffer *rxb, 
		rxb->page = NULL;

	}



	spin_lock_irqsave(&trans->hcmd_lock, flags);



	iwl_hcmd_queue_reclaim(trans, txq_id, index);



	if (!(meta->flags & CMD_ASYNC)) {
@@ -898,7 +900,7 @@ void iwl_tx_cmd_complete(struct iwl_trans *trans, struct iwl_rx_mem_buffer *rxb, 


	meta->flags = 0;



	spin_unlock_irqrestore(&trans->hcmd_lock, flags);

	spin_unlock(&txq->lock);

}



#define HOST_COMPLETE_TIMEOUT (2 * HZ)
@@ -1041,6 +1043,8 @@ int iwl_tx_queue_reclaim(struct iwl_trans *trans, int txq_id, int index, 
	if (WARN_ON(txq_id == trans->shrd->cmd_queue))

		return 0;



	lockdep_assert_held(&txq->lock);



	/*Since we free until index _not_ inclusive, the one before index is

	 * the last we will free. This one must be used */

	last_to_free = iwl_queue_dec_wrap(index, q->n_bd);

drivers/net/wireless/iwlwifi/iwl-trans-pcie.c

+19 −12
Original line number Diff line number Diff line
@@ -390,6 +390,8 @@ static int iwl_trans_txq_init(struct iwl_trans *trans, struct iwl_tx_queue *txq, 
	if (ret)

		return ret;



	spin_lock_init(&txq->lock);



	/*

	 * Tell nic where to find circular buffer of Tx Frame Descriptors for

	 * given Tx queue, and enable the DMA channel used for that queue.
@@ -409,8 +411,6 @@ static void iwl_tx_queue_unmap(struct iwl_trans *trans, int txq_id) 
	struct iwl_tx_queue *txq = &trans_pcie->txq[txq_id];

	struct iwl_queue *q = &txq->q;

	enum dma_data_direction dma_dir;

	unsigned long flags;

	spinlock_t *lock;



	if (!q->n_bd)

		return;
@@ -418,22 +418,19 @@ static void iwl_tx_queue_unmap(struct iwl_trans *trans, int txq_id) 
	/* In the command queue, all the TBs are mapped as BIDI

	 * so unmap them as such.

	 */

	if (txq_id == trans->shrd->cmd_queue) {

	if (txq_id == trans->shrd->cmd_queue)

		dma_dir = DMA_BIDIRECTIONAL;

		lock = &trans->hcmd_lock;

	} else {

	else

		dma_dir = DMA_TO_DEVICE;

		lock = &trans->shrd->sta_lock;

	}



	spin_lock_irqsave(lock, flags);

	spin_lock_bh(&txq->lock);

	while (q->write_ptr != q->read_ptr) {

		/* The read_ptr needs to bound by q->n_window */

		iwlagn_txq_free_tfd(trans, txq, get_cmd_index(q, q->read_ptr),

				    dma_dir);

		q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd);

	}

	spin_unlock_irqrestore(lock, flags);

	spin_unlock_bh(&txq->lock);

}



/**
@@ -1358,6 +1355,8 @@ static int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb, 
	txq = &trans_pcie->txq[txq_id];

	q = &txq->q;



	spin_lock(&txq->lock);



	/* In AGG mode, the index in the ring must correspond to the WiFi

	 * sequence number. This is a HW requirements to help the SCD to parse

	 * the BA.
@@ -1404,7 +1403,7 @@ static int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb, 
				    &dev_cmd->hdr, firstlen,

				    DMA_BIDIRECTIONAL);

	if (unlikely(dma_mapping_error(trans->dev, txcmd_phys)))

		return -1;

		goto out_err;

	dma_unmap_addr_set(out_meta, mapping, txcmd_phys);

	dma_unmap_len_set(out_meta, len, firstlen);
@@ -1426,7 +1425,7 @@ static int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb, 
					 dma_unmap_addr(out_meta, mapping),

					 dma_unmap_len(out_meta, len),

					 DMA_BIDIRECTIONAL);

			return -1;

			goto out_err;

		}

	}
@@ -1481,7 +1480,11 @@ static int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb, 
			iwl_stop_queue(trans, txq, "Queue is full");

		}

	}

	spin_unlock(&txq->lock);

	return 0;

 out_err:

	spin_unlock(&txq->lock);

	return -1;

}



static int iwl_trans_pcie_start_hw(struct iwl_trans *trans)
@@ -1560,6 +1563,8 @@ static int iwl_trans_pcie_reclaim(struct iwl_trans *trans, int sta_id, int tid, 
	int tfd_num = ssn & (txq->q.n_bd - 1);

	int freed = 0;



	spin_lock(&txq->lock);



	txq->time_stamp = jiffies;



	if (unlikely(txq_id >= IWLAGN_FIRST_AMPDU_QUEUE &&
@@ -1574,6 +1579,7 @@ static int iwl_trans_pcie_reclaim(struct iwl_trans *trans, int sta_id, int tid, 
		IWL_DEBUG_TX_QUEUES(trans, "Bad queue mapping txq_id %d, "

			"agg_txq[sta_id[tid] %d", txq_id,

			trans_pcie->agg_txq[sta_id][tid]);

		spin_unlock(&txq->lock);

		return 1;

	}
@@ -1587,6 +1593,8 @@ static int iwl_trans_pcie_reclaim(struct iwl_trans *trans, int sta_id, int tid, 
		   status != TX_STATUS_FAIL_PASSIVE_NO_RX))

			iwl_wake_queue(trans, txq, "Packets reclaimed");

	}



	spin_unlock(&txq->lock);

	return 0;

}
@@ -2267,7 +2275,6 @@ struct iwl_trans *iwl_trans_pcie_alloc(struct iwl_shared *shrd, 
	trans->ops = &trans_ops_pcie;

	trans->shrd = shrd;

	trans_pcie->trans = trans;

	spin_lock_init(&trans->hcmd_lock);

	spin_lock_init(&trans_pcie->irq_lock);



	/* W/A - seems to solve weird behavior. We need to remove this if we

drivers/net/wireless/iwlwifi/iwl-trans.h

+0 −2
Original line number Diff line number Diff line
@@ -309,7 +309,6 @@ enum iwl_trans_state { 
 * @ops - pointer to iwl_trans_ops

 * @op_mode - pointer to the op_mode

 * @shrd - pointer to iwl_shared which holds shared data from the upper layer

 * @hcmd_lock: protects HCMD

 * @reg_lock - protect hw register access

 * @dev - pointer to struct device * that represents the device

 * @irq - the irq number for the device
@@ -326,7 +325,6 @@ struct iwl_trans { 
	struct iwl_op_mode *op_mode;

	struct iwl_shared *shrd;

	enum iwl_trans_state state;

	spinlock_t hcmd_lock;

	spinlock_t reg_lock;



	struct device *dev;