[PATCH net 1/3] net: mvpp2: fix TSO headers allocation and management

From: Yan Markman <redacted>

TSO headers are managed with txq index and therefore should be aligned
with the txq size, not with the aggregated txq size.

Fixes: 186cd4d4e414 ("net: mvpp2: software tso support")
Reported-by: Marc Zyngier <redacted>
Signed-off-by: Yan Markman <redacted>
Signed-off-by: Antoine Tenart <redacted>
---
 drivers/net/ethernet/marvell/mvpp2.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c
index 1a540c88c974..2898ac70b826 100644
--- a/drivers/net/ethernet/marvell/mvpp2.c
+++ b/drivers/net/ethernet/marvell/mvpp2.c

@@ -5609,7 +5609,7 @@ static int mvpp2_txq_init(struct mvpp2_port *port,
 
 		txq_pcpu->tso_headers =
 			dma_alloc_coherent(port->dev->dev.parent,
-					   MVPP2_AGGR_TXQ_SIZE * TSO_HEADER_SIZE,
+					   txq_pcpu->size * TSO_HEADER_SIZE,
 					   &txq_pcpu->tso_headers_dma,
 					   GFP_KERNEL);
 		if (!txq_pcpu->tso_headers)

@@ -5623,7 +5623,7 @@ static int mvpp2_txq_init(struct mvpp2_port *port,
 		kfree(txq_pcpu->buffs);
 
 		dma_free_coherent(port->dev->dev.parent,
-				  MVPP2_AGGR_TXQ_SIZE * MVPP2_DESC_ALIGNED_SIZE,
+				  txq_pcpu->size * TSO_HEADER_SIZE,
 				  txq_pcpu->tso_headers,
 				  txq_pcpu->tso_headers_dma);
 	}

@@ -5647,7 +5647,7 @@ static void mvpp2_txq_deinit(struct mvpp2_port *port,
 		kfree(txq_pcpu->buffs);
 
 		dma_free_coherent(port->dev->dev.parent,
-				  MVPP2_AGGR_TXQ_SIZE * MVPP2_DESC_ALIGNED_SIZE,
+				  txq_pcpu->size * TSO_HEADER_SIZE,
 				  txq_pcpu->tso_headers,
 				  txq_pcpu->tso_headers_dma);
 	}

-- 
2.14.2

When Tx IRQs are used, txq_bufs_free() can be called from both the Tx
path and from NAPI poll(). This led to CPU stalls as if these two tasks
(Tx and Poll) are scheduled on two CPUs at the same time, DMA unmapping
operations are done on the same txq buffers.

This patch adds a check not to call txq_done() from the Tx path if Tx
interrupts are used as it does not make sense to do so.

Fixes: edc660fa09e2 ("net: mvpp2: replace TX coalescing interrupts with hrtimer")
Signed-off-by: Antoine Tenart <redacted>
---
 drivers/net/ethernet/marvell/mvpp2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c
index 037f26dfe31c..60b4f3d995af 100644
--- a/drivers/net/ethernet/marvell/mvpp2.c
+++ b/drivers/net/ethernet/marvell/mvpp2.c

@@ -6499,7 +6499,7 @@ static int mvpp2_tx(struct sk_buff *skb, struct net_device *dev)
 	}
 
 	/* Finalize TX processing */
-	if (txq_pcpu->count >= txq->done_pkts_coal)
+	if (!port->has_tx_irqs && txq_pcpu->count >= txq->done_pkts_coal)
 		mvpp2_txq_done(port, txq, txq_pcpu);
 
 	/* Set the timer in case not all frags were processed */

-- 
2.14.2

The TSO header buffers are coming from a per cpu pool and should not
be unmapped as they are reused. The PPv2 driver was unmapping all
descriptors buffers unconditionally. This patch fixes this by checking
the buffers dma addresses before unmapping them, and by not unmapping
those who are located in the TSO header pool.

Fixes: 186cd4d4e414 ("net: mvpp2: software tso support")
Signed-off-by: Antoine Tenart <redacted>
---
 drivers/net/ethernet/marvell/mvpp2.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c
index 2898ac70b826..037f26dfe31c 100644
--- a/drivers/net/ethernet/marvell/mvpp2.c
+++ b/drivers/net/ethernet/marvell/mvpp2.c

@@ -1167,6 +1167,11 @@ struct mvpp2_bm_pool {
 	u32 port_map;
 };
 
+#define IS_TSO_HEADER(txq_pcpu, addr) \
+	((addr) >= (txq_pcpu)->tso_headers_dma && \
+	 (addr) < (txq_pcpu)->tso_headers_dma + \
+	 (txq_pcpu)->size * TSO_HEADER_SIZE)
+
 /* Queue modes */
 #define MVPP2_QDIST_SINGLE_MODE	0
 #define MVPP2_QDIST_MULTI_MODE	1

@@ -5321,8 +5326,9 @@ static void mvpp2_txq_bufs_free(struct mvpp2_port *port,
 		struct mvpp2_txq_pcpu_buf *tx_buf =
 			txq_pcpu->buffs + txq_pcpu->txq_get_index;
 
-		dma_unmap_single(port->dev->dev.parent, tx_buf->dma,
-				 tx_buf->size, DMA_TO_DEVICE);
+		if (!IS_TSO_HEADER(txq_pcpu, tx_buf->dma))
+			dma_unmap_single(port->dev->dev.parent, tx_buf->dma,
+					 tx_buf->size, DMA_TO_DEVICE);
 		if (tx_buf->skb)
 			dev_kfree_skb_any(tx_buf->skb);
 

@@ -6212,12 +6218,15 @@ static inline void
 tx_desc_unmap_put(struct mvpp2_port *port, struct mvpp2_tx_queue *txq,
 		  struct mvpp2_tx_desc *desc)
 {
+	struct mvpp2_txq_pcpu *txq_pcpu = this_cpu_ptr(txq->pcpu);
+
 	dma_addr_t buf_dma_addr =
 		mvpp2_txdesc_dma_addr_get(port, desc);
 	size_t buf_sz =
 		mvpp2_txdesc_size_get(port, desc);
-	dma_unmap_single(port->dev->dev.parent, buf_dma_addr,
-			 buf_sz, DMA_TO_DEVICE);
+	if (!IS_TSO_HEADER(txq_pcpu, buf_dma_addr))
+		dma_unmap_single(port->dev->dev.parent, buf_dma_addr,
+				 buf_sz, DMA_TO_DEVICE);
 	mvpp2_txq_desc_put(txq);
 }
 

-- 
2.14.2

From: Antoine Tenart <redacted>
Date: Mon, 23 Oct 2017 15:24:29 +0200

From: Yan Markman <redacted>

TSO headers are managed with txq index and therefore should be aligned
with the txq size, not with the aggregated txq size.

Fixes: 186cd4d4e414 ("net: mvpp2: software tso support")
Reported-by: Marc Zyngier <redacted>
Signed-off-by: Yan Markman <redacted>
Signed-off-by: Antoine Tenart <redacted>

Applied.

From: Antoine Tenart <redacted>
Date: Mon, 23 Oct 2017 15:24:30 +0200

The TSO header buffers are coming from a per cpu pool and should not
be unmapped as they are reused. The PPv2 driver was unmapping all
descriptors buffers unconditionally. This patch fixes this by checking
the buffers dma addresses before unmapping them, and by not unmapping
those who are located in the TSO header pool.

Fixes: 186cd4d4e414 ("net: mvpp2: software tso support")
Signed-off-by: Antoine Tenart <redacted>

Applied.

From: Antoine Tenart <redacted>
Date: Mon, 23 Oct 2017 15:24:31 +0200

When Tx IRQs are used, txq_bufs_free() can be called from both the Tx
path and from NAPI poll(). This led to CPU stalls as if these two tasks
(Tx and Poll) are scheduled on two CPUs at the same time, DMA unmapping
operations are done on the same txq buffers.

This patch adds a check not to call txq_done() from the Tx path if Tx
interrupts are used as it does not make sense to do so.

Fixes: edc660fa09e2 ("net: mvpp2: replace TX coalescing interrupts with hrtimer")
Signed-off-by: Antoine Tenart <redacted>

Applied.