From 71ce391dfb7843f4d31abcd7287967a00cb1b8a1 Mon Sep 17 00:00:00 2001 From: Marcin Wojtas Date: Thu, 6 Aug 2015 19:00:29 +0200 Subject: [PATCH] net: mvpp2: enable proper per-CPU TX buffers unmapping mvpp2 driver allows usage of per-CPU TX processing. Once the packets are prepared independetly on each CPU, the hardware enqueues the descriptors in common TX queue. After they are sent, the buffers and associated sk_buffs should be released on the corresponding CPU. This is why a special index is maintained in order to point to the right data to be released after transmission takes place. Each per-CPU TX queue comprise an array of sent sk_buffs, freed in mvpp2_txq_bufs_free function. However, the index was used there also for obtaining a descriptor (and therefore a buffer to be DMA-unmapped) from common TX queue, which was wrong, because it was not referring to the current CPU. This commit enables proper unmapping of sent data buffers by indexing them in per-CPU queues using a dedicated array for keeping their physical addresses. Signed-off-by: Marcin Wojtas Signed-off-by: David S. Miller --- drivers/net/ethernet/marvell/mvpp2.c | 52 +++++++++++++++++++++++++----------- 1 file changed, 37 insertions(+), 15 deletions(-) diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c index f94bd12..3e25d314 100644 --- a/drivers/net/ethernet/marvell/mvpp2.c +++ b/drivers/net/ethernet/marvell/mvpp2.c @@ -776,6 +776,9 @@ struct mvpp2_txq_pcpu { /* Array of transmitted skb */ struct sk_buff **tx_skb; + /* Array of transmitted buffers' physical addresses */ + dma_addr_t *tx_buffs; + /* Index of last TX DMA descriptor that was inserted */ int txq_put_index; @@ -961,9 +964,13 @@ static void mvpp2_txq_inc_get(struct mvpp2_txq_pcpu *txq_pcpu) } static void mvpp2_txq_inc_put(struct mvpp2_txq_pcpu *txq_pcpu, - struct sk_buff *skb) + struct sk_buff *skb, + struct mvpp2_tx_desc *tx_desc) { txq_pcpu->tx_skb[txq_pcpu->txq_put_index] = skb; + if (skb) + txq_pcpu->tx_buffs[txq_pcpu->txq_put_index] = + tx_desc->buf_phys_addr; txq_pcpu->txq_put_index++; if (txq_pcpu->txq_put_index == txq_pcpu->size) txq_pcpu->txq_put_index = 0; @@ -4392,8 +4399,8 @@ static void mvpp2_txq_bufs_free(struct mvpp2_port *port, int i; for (i = 0; i < num; i++) { - struct mvpp2_tx_desc *tx_desc = txq->descs + - txq_pcpu->txq_get_index; + dma_addr_t buf_phys_addr = + txq_pcpu->tx_buffs[txq_pcpu->txq_get_index]; struct sk_buff *skb = txq_pcpu->tx_skb[txq_pcpu->txq_get_index]; mvpp2_txq_inc_get(txq_pcpu); @@ -4401,8 +4408,8 @@ static void mvpp2_txq_bufs_free(struct mvpp2_port *port, if (!skb) continue; - dma_unmap_single(port->dev->dev.parent, tx_desc->buf_phys_addr, - tx_desc->data_size, DMA_TO_DEVICE); + dma_unmap_single(port->dev->dev.parent, buf_phys_addr, + skb_headlen(skb), DMA_TO_DEVICE); dev_kfree_skb_any(skb); } } @@ -4634,12 +4641,13 @@ static int mvpp2_txq_init(struct mvpp2_port *port, txq_pcpu->tx_skb = kmalloc(txq_pcpu->size * sizeof(*txq_pcpu->tx_skb), GFP_KERNEL); - if (!txq_pcpu->tx_skb) { - dma_free_coherent(port->dev->dev.parent, - txq->size * MVPP2_DESC_ALIGNED_SIZE, - txq->descs, txq->descs_phys); - return -ENOMEM; - } + if (!txq_pcpu->tx_skb) + goto error; + + txq_pcpu->tx_buffs = kmalloc(txq_pcpu->size * + sizeof(dma_addr_t), GFP_KERNEL); + if (!txq_pcpu->tx_buffs) + goto error; txq_pcpu->count = 0; txq_pcpu->reserved_num = 0; @@ -4648,6 +4656,19 @@ static int mvpp2_txq_init(struct mvpp2_port *port, } return 0; + +error: + for_each_present_cpu(cpu) { + txq_pcpu = per_cpu_ptr(txq->pcpu, cpu); + kfree(txq_pcpu->tx_skb); + kfree(txq_pcpu->tx_buffs); + } + + dma_free_coherent(port->dev->dev.parent, + txq->size * MVPP2_DESC_ALIGNED_SIZE, + txq->descs, txq->descs_phys); + + return -ENOMEM; } /* Free allocated TXQ resources */ @@ -4660,6 +4681,7 @@ static void mvpp2_txq_deinit(struct mvpp2_port *port, for_each_present_cpu(cpu) { txq_pcpu = per_cpu_ptr(txq->pcpu, cpu); kfree(txq_pcpu->tx_skb); + kfree(txq_pcpu->tx_buffs); } if (txq->descs) @@ -5129,11 +5151,11 @@ static int mvpp2_tx_frag_process(struct mvpp2_port *port, struct sk_buff *skb, if (i == (skb_shinfo(skb)->nr_frags - 1)) { /* Last descriptor */ tx_desc->command = MVPP2_TXD_L_DESC; - mvpp2_txq_inc_put(txq_pcpu, skb); + mvpp2_txq_inc_put(txq_pcpu, skb, tx_desc); } else { /* Descriptor in the middle: Not First, Not Last */ tx_desc->command = 0; - mvpp2_txq_inc_put(txq_pcpu, NULL); + mvpp2_txq_inc_put(txq_pcpu, NULL, tx_desc); } } @@ -5199,12 +5221,12 @@ static int mvpp2_tx(struct sk_buff *skb, struct net_device *dev) /* First and Last descriptor */ tx_cmd |= MVPP2_TXD_F_DESC | MVPP2_TXD_L_DESC; tx_desc->command = tx_cmd; - mvpp2_txq_inc_put(txq_pcpu, skb); + mvpp2_txq_inc_put(txq_pcpu, skb, tx_desc); } else { /* First but not Last */ tx_cmd |= MVPP2_TXD_F_DESC | MVPP2_TXD_PADDING_DISABLE; tx_desc->command = tx_cmd; - mvpp2_txq_inc_put(txq_pcpu, NULL); + mvpp2_txq_inc_put(txq_pcpu, NULL, tx_desc); /* Continue with other skb fragments */ if (mvpp2_tx_frag_process(port, skb, aggr_txq, txq)) { -- 2.7.4