1 files changed, 73 insertions, 75 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
index 489b07a9e471..4be3c35afd19 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
@@ -231,6 +231,9 @@ static void iwl_pcie_rxq_check_wrptr(struct iwl_trans *trans)
 	}
 }
 
+/*
+ * iwl_pcie_rxq_mq_restock - restock implementation for multi-queue rx
+ */
 static void iwl_pcie_rxq_mq_restock(struct iwl_trans *trans,
 				    struct iwl_rxq *rxq)
 {
@@ -277,17 +280,10 @@ static void iwl_pcie_rxq_mq_restock(struct iwl_trans *trans,
 }
 
 /*
- * iwl_pcie_rxq_restock - refill RX queue from pre-allocated pool
- *
- * If there are slots in the RX queue that need to be restocked,
- * and we have free pre-allocated buffers, fill the ranks as much
- * as we can, pulling from rx_free.
- *
- * This moves the 'write' index forward to catch up with 'processed', and
- * also updates the memory address in the firmware to reference the new
- * target buffer.
+ * iwl_pcie_rxq_sq_restock - restock implementation for single queue rx
  */
-static void iwl_pcie_rxq_restock(struct iwl_trans *trans, struct iwl_rxq *rxq)
+static void iwl_pcie_rxq_sq_restock(struct iwl_trans *trans,
+				    struct iwl_rxq *rxq)
 {
 	struct iwl_rx_mem_buffer *rxb;
 
@@ -332,6 +328,26 @@ static void iwl_pcie_rxq_restock(struct iwl_trans *trans, struct iwl_rxq *rxq)
 }
 
 /*
+ * iwl_pcie_rxq_restock - refill RX queue from pre-allocated pool
+ *
+ * If there are slots in the RX queue that need to be restocked,
+ * and we have free pre-allocated buffers, fill the ranks as much
+ * as we can, pulling from rx_free.
+ *
+ * This moves the 'write' index forward to catch up with 'processed', and
+ * also updates the memory address in the firmware to reference the new
+ * target buffer.
+ */
+static
+void iwl_pcie_rxq_restock(struct iwl_trans *trans, struct iwl_rxq *rxq)
+{
+	if (trans->cfg->mq_rx_supported)
+		iwl_pcie_rxq_mq_restock(trans, rxq);
+	else
+		iwl_pcie_rxq_sq_restock(trans, rxq);
+}
+
+/*
  * iwl_pcie_rx_alloc_page - allocates and returns a page.
  *
  */
@@ -434,7 +450,7 @@ static void iwl_pcie_free_rbs_pool(struct iwl_trans *trans)
 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 	int i;
 
-	for (i = 0; i < MQ_RX_POOL_SIZE; i++) {
+	for (i = 0; i < RX_POOL_SIZE; i++) {
 		if (!trans_pcie->rx_pool[i].page)
 			continue;
 		dma_unmap_page(trans->dev, trans_pcie->rx_pool[i].page_dma,
@@ -539,40 +555,46 @@ static void iwl_pcie_rx_allocator(struct iwl_trans *trans)
 }
 
 /*
- * iwl_pcie_rx_allocator_get - Returns the pre-allocated pages
+ * iwl_pcie_rx_allocator_get - returns the pre-allocated pages
 .*
 .* Called by queue when the queue posted allocation request and
  * has freed 8 RBDs in order to restock itself.
+ * This function directly moves the allocated RBs to the queue's ownership
+ * and updates the relevant counters.
  */
-static int iwl_pcie_rx_allocator_get(struct iwl_trans *trans,
-				     struct iwl_rx_mem_buffer
-				     *out[RX_CLAIM_REQ_ALLOC])
+static void iwl_pcie_rx_allocator_get(struct iwl_trans *trans,
+				      struct iwl_rxq *rxq)
 {
 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
 	int i;
 
+	lockdep_assert_held(&rxq->lock);
+
 	/*
 	 * atomic_dec_if_positive returns req_ready - 1 for any scenario.
 	 * If req_ready is 0 atomic_dec_if_positive will return -1 and this
-	 * function will return -ENOMEM, as there are no ready requests.
+	 * function will return early, as there are no ready requests.
 	 * atomic_dec_if_positive will perofrm the *actual* decrement only if
 	 * req_ready > 0, i.e. - there are ready requests and the function
 	 * hands one request to the caller.
 	 */
 	if (atomic_dec_if_positive(&rba->req_ready) < 0)
-		return -ENOMEM;
+		return;
 
 	spin_lock(&rba->lock);
 	for (i = 0; i < RX_CLAIM_REQ_ALLOC; i++) {
 		/* Get next free Rx buffer, remove it from free list */
-		out[i] = list_first_entry(&rba->rbd_allocated,
-			       struct iwl_rx_mem_buffer, list);
-		list_del(&out[i]->list);
+		struct iwl_rx_mem_buffer *rxb =
+			list_first_entry(&rba->rbd_allocated,
+					 struct iwl_rx_mem_buffer, list);
+
+		list_move(&rxb->list, &rxq->rx_free);
 	}
 	spin_unlock(&rba->lock);
 
-	return 0;
+	rxq->used_count -= RX_CLAIM_REQ_ALLOC;
+	rxq->free_count += RX_CLAIM_REQ_ALLOC;
 }
 
 static void iwl_pcie_rx_allocator_work(struct work_struct *data)
@@ -795,11 +817,10 @@ static void iwl_pcie_rx_mq_hw_init(struct iwl_trans *trans)
 
 	/*
 	 * Activate DMA snooping.
-	 * Set RX DMA chunk size to 128 bit
+	 * Set RX DMA chunk size to 64B
 	 * Default queue is 0
 	 */
 	iwl_write_prph(trans, RFH_GEN_CFG, RFH_GEN_CFG_RFH_DMA_SNOOP |
-		       RFH_GEN_CFG_RB_CHUNK_SIZE |
 		       (DEFAULT_RXQ_NUM << RFH_GEN_CFG_DEFAULT_RXQ_NUM_POS) |
 		       RFH_GEN_CFG_SERVICE_DMA_SNOOP);
 	/* Enable the relevant rx queues */
@@ -830,7 +851,7 @@ int iwl_pcie_rx_init(struct iwl_trans *trans)
 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 	struct iwl_rxq *def_rxq;
 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
-	int i, err, num_rbds, allocator_pool_size;
+	int i, err, queue_size, allocator_pool_size, num_alloc;
 
 	if (!trans_pcie->rxq) {
 		err = iwl_pcie_rx_alloc(trans);
@@ -882,11 +903,12 @@ int iwl_pcie_rx_init(struct iwl_trans *trans)
 	}
 
 	/* move the pool to the default queue and allocator ownerships */
-	num_rbds = trans->cfg->mq_rx_supported ?
-		     MQ_RX_POOL_SIZE : RX_QUEUE_SIZE;
+	queue_size = trans->cfg->mq_rx_supported ?
+		     MQ_RX_NUM_RBDS : RX_QUEUE_SIZE;
 	allocator_pool_size = trans->num_rx_queues *
 		(RX_CLAIM_REQ_ALLOC - RX_POST_REQ_ALLOC);
-	for (i = 0; i < num_rbds; i++) {
+	num_alloc = queue_size + allocator_pool_size;
+	for (i = 0; i < num_alloc; i++) {
 		struct iwl_rx_mem_buffer *rxb = &trans_pcie->rx_pool[i];
 
 		if (i < allocator_pool_size)
@@ -901,7 +923,7 @@ int iwl_pcie_rx_init(struct iwl_trans *trans)
 	if (trans->cfg->mq_rx_supported) {
 		iwl_pcie_rx_mq_hw_init(trans);
 	} else {
-		iwl_pcie_rxq_restock(trans, def_rxq);
+		iwl_pcie_rxq_sq_restock(trans, def_rxq);
 		iwl_pcie_rx_hw_init(trans, def_rxq);
 	}
 
@@ -1149,7 +1171,7 @@ static void iwl_pcie_rx_handle(struct iwl_trans *trans, int queue)
 {
 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 	struct iwl_rxq *rxq = &trans_pcie->rxq[queue];
-	u32 r, i, j, count = 0;
+	u32 r, i, count = 0;
 	bool emergency = false;
 
 restart:
@@ -1193,62 +1215,36 @@ restart:
 
 		i = (i + 1) & (rxq->queue_size - 1);
 
-		/* If we have RX_CLAIM_REQ_ALLOC released rx buffers -
-		 * try to claim the pre-allocated buffers from the allocator */
-		if (rxq->used_count >= RX_CLAIM_REQ_ALLOC) {
+		/*
+		 * If we have RX_CLAIM_REQ_ALLOC released rx buffers -
+		 * try to claim the pre-allocated buffers from the allocator.
+		 * If not ready - will try to reclaim next time.
+		 * There is no need to reschedule work - allocator exits only
+		 * on success
+		 */
+		if (rxq->used_count >= RX_CLAIM_REQ_ALLOC)
+			iwl_pcie_rx_allocator_get(trans, rxq);
+
+		if (rxq->used_count % RX_CLAIM_REQ_ALLOC == 0 && !emergency) {
 			struct iwl_rb_allocator *rba = &trans_pcie->rba;
-			struct iwl_rx_mem_buffer *out[RX_CLAIM_REQ_ALLOC];
-
-			if (rxq->used_count % RX_CLAIM_REQ_ALLOC == 0 &&
-			    !emergency) {
-				/* Add the remaining 6 empty RBDs
-				* for allocator use
-				 */
-				spin_lock(&rba->lock);
-				list_splice_tail_init(&rxq->rx_used,
-						      &rba->rbd_empty);
-				spin_unlock(&rba->lock);
-			}
 
-			/* If not ready - continue, will try to reclaim later.
-			* No need to reschedule work - allocator exits only on
-			* success */
-			if (!iwl_pcie_rx_allocator_get(trans, out)) {
-				/* If success - then RX_CLAIM_REQ_ALLOC
-				 * buffers were retrieved and should be added
-				 * to free list */
-				rxq->used_count -= RX_CLAIM_REQ_ALLOC;
-				for (j = 0; j < RX_CLAIM_REQ_ALLOC; j++) {
-					list_add_tail(&out[j]->list,
-						      &rxq->rx_free);
-					rxq->free_count++;
-				}
-			}
-		}
-		if (emergency) {
+			/* Add the remaining empty RBDs for allocator use */
+			spin_lock(&rba->lock);
+			list_splice_tail_init(&rxq->rx_used, &rba->rbd_empty);
+			spin_unlock(&rba->lock);
+		} else if (emergency) {
 			count++;
 			if (count == 8) {
 				count = 0;
 				if (rxq->used_count < rxq->queue_size / 3)
 					emergency = false;
+
+				rxq->read = i;
 				spin_unlock(&rxq->lock);
 				iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq);
-				spin_lock(&rxq->lock);
-			}
-		}
-		/* handle restock for three cases, can be all of them at once:
-		* - we just pulled buffers from the allocator
-		* - we have 8+ unstolen pages accumulated
-		* - we are in emergency and allocated buffers
-		 */
-		if (rxq->free_count >=  RX_CLAIM_REQ_ALLOC) {
-			rxq->read = i;
-			spin_unlock(&rxq->lock);
-			if (trans->cfg->mq_rx_supported)
-				iwl_pcie_rxq_mq_restock(trans, rxq);
-			else
 				iwl_pcie_rxq_restock(trans, rxq);
-			goto restart;
+				goto restart;
+			}
 		}
 	}
 out:
@@ -1273,6 +1269,8 @@ out:
 
 	if (rxq->napi.poll)
 		napi_gro_flush(&rxq->napi, false);
+
+	iwl_pcie_rxq_restock(trans, rxq);
 }
 
 static struct iwl_trans_pcie *iwl_pcie_get_trans_pcie(struct msix_entry *entry)