Commit e72e5659 authored by Scott Peterson's avatar Scott Peterson Committed by Jeff Kirsher
Browse files

i40e/i40evf: Moves skb from i40e_rx_buffer to i40e_ring 



This patch reduces the size of struct i40e_rx_buffer by one pointer,
and makes the i40e driver a little more consistent with the igb driver
in terms of packets that span buffers.

We do this by moving the skb field from struct i40e_rx_buffer to
struct i40e_ring. We pass the skb we already have (or NULL if we
don't) to i40e_fetch_rx_buffer(), which skips the skb allocation if we
already have one for this packet.

Change-ID: I4ad48a531844494ba0c5d8e1a62209a057f661b0
Signed-off-by: default avatarScott Peterson <scott.d.peterson@intel.com>
Tested-by: default avatarAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
parent 7987dcd7

drivers/net/ethernet/intel/i40e/i40e_txrx.c

+15 −16
Original line number Diff line number Diff line
@@ -1013,14 +1013,15 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring) 
	if (!rx_ring->rx_bi)

		return;



	if (rx_ring->skb) {

		dev_kfree_skb(rx_ring->skb);

		rx_ring->skb = NULL;

	}



	/* Free all the Rx ring sk_buffs */

	for (i = 0; i < rx_ring->count; i++) {

		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];



		if (rx_bi->skb) {

			dev_kfree_skb(rx_bi->skb);

			rx_bi->skb = NULL;

		}

		if (!rx_bi->page)

			continue;
@@ -1608,7 +1609,8 @@ static bool i40e_add_rx_frag(struct i40e_ring *rx_ring, 
 */

static inline

struct sk_buff *i40e_fetch_rx_buffer(struct i40e_ring *rx_ring,

				     union i40e_rx_desc *rx_desc)

				     union i40e_rx_desc *rx_desc,

				     struct sk_buff *skb)

{

	u64 local_status_error_len =

		le64_to_cpu(rx_desc->wb.qword1.status_error_len);
@@ -1616,15 +1618,12 @@ struct sk_buff *i40e_fetch_rx_buffer(struct i40e_ring *rx_ring, 
		(local_status_error_len & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>

		I40E_RXD_QW1_LENGTH_PBUF_SHIFT;

	struct i40e_rx_buffer *rx_buffer;

	struct sk_buff *skb;

	struct page *page;



	rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];

	page = rx_buffer->page;

	prefetchw(page);



	skb = rx_buffer->skb;



	if (likely(!skb)) {

		void *page_addr = page_address(page) + rx_buffer->page_offset;
@@ -1648,8 +1647,6 @@ struct sk_buff *i40e_fetch_rx_buffer(struct i40e_ring *rx_ring, 
		 * it now to avoid a possible cache miss

		 */

		prefetchw(skb->data);

	} else {

		rx_buffer->skb = NULL;

	}



	/* we are reusing so sync this buffer for CPU use */
@@ -1702,7 +1699,6 @@ static bool i40e_is_non_eop(struct i40e_ring *rx_ring, 
#define staterrlen rx_desc->wb.qword1.status_error_len

	if (unlikely(i40e_rx_is_programming_status(le64_to_cpu(staterrlen)))) {

		i40e_clean_programming_status(rx_ring, rx_desc);

		rx_ring->rx_bi[ntc].skb = skb;

		return true;

	}

	/* if we are the last buffer then there is nothing else to do */
@@ -1710,8 +1706,6 @@ static bool i40e_is_non_eop(struct i40e_ring *rx_ring, 
	if (likely(i40e_test_staterr(rx_desc, I40E_RXD_EOF)))

		return false;



	/* place skb in next buffer to be received */

	rx_ring->rx_bi[ntc].skb = skb;

	rx_ring->rx_stats.non_eop_descs++;



	return true;
@@ -1732,12 +1726,12 @@ static bool i40e_is_non_eop(struct i40e_ring *rx_ring, 
static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)

{

	unsigned int total_rx_bytes = 0, total_rx_packets = 0;

	struct sk_buff *skb = rx_ring->skb;

	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);

	bool failure = false;



	while (likely(total_rx_packets < budget)) {

		union i40e_rx_desc *rx_desc;

		struct sk_buff *skb;

		u16 vlan_tag;

		u8 rx_ptype;

		u64 qword;
@@ -1766,7 +1760,7 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) 
		 */

		dma_rmb();



		skb = i40e_fetch_rx_buffer(rx_ring, rx_desc);

		skb = i40e_fetch_rx_buffer(rx_ring, rx_desc, skb);

		if (!skb)

			break;
@@ -1785,8 +1779,10 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) 
			continue;

		}



		if (i40e_cleanup_headers(rx_ring, skb))

		if (i40e_cleanup_headers(rx_ring, skb)) {

			skb = NULL;

			continue;

		}



		/* probably a little skewed due to removing CRC */

		total_rx_bytes += skb->len;
@@ -1811,11 +1807,14 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) 
			   le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1) : 0;



		i40e_receive_skb(rx_ring, skb, vlan_tag);

		skb = NULL;



		/* update budget accounting */

		total_rx_packets++;

	}



	rx_ring->skb = skb;



	u64_stats_update_begin(&rx_ring->syncp);

	rx_ring->stats.packets += total_rx_packets;

	rx_ring->stats.bytes += total_rx_bytes;

drivers/net/ethernet/intel/i40e/i40e_txrx.h

+8 −1
Original line number Diff line number Diff line
@@ -253,7 +253,6 @@ struct i40e_tx_buffer { 
};



struct i40e_rx_buffer {

	struct sk_buff *skb;

	dma_addr_t dma;

	struct page *page;

	unsigned int page_offset;
@@ -354,6 +353,14 @@ struct i40e_ring { 


	struct rcu_head rcu;		/* to avoid race on free */

	u16 next_to_alloc;

	struct sk_buff *skb;		/* When i40e_clean_rx_ring_irq() must

					 * return before it sees the EOP for

					 * the current packet, we save that skb

					 * here and resume receiving this

					 * packet the next time

					 * i40e_clean_rx_ring_irq() is called

					 * for this ring.

					 */

} ____cacheline_internodealigned_in_smp;



enum i40e_latency_range {

drivers/net/ethernet/intel/i40evf/i40e_txrx.c

+15 −15
Original line number Diff line number Diff line
@@ -501,14 +501,15 @@ void i40evf_clean_rx_ring(struct i40e_ring *rx_ring) 
	if (!rx_ring->rx_bi)

		return;



	if (rx_ring->skb) {

		dev_kfree_skb(rx_ring->skb);

		rx_ring->skb = NULL;

	}



	/* Free all the Rx ring sk_buffs */

	for (i = 0; i < rx_ring->count; i++) {

		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];



		if (rx_bi->skb) {

			dev_kfree_skb(rx_bi->skb);

			rx_bi->skb = NULL;

		}

		if (!rx_bi->page)

			continue;
@@ -1086,7 +1087,8 @@ static bool i40e_add_rx_frag(struct i40e_ring *rx_ring, 
 */

static inline

struct sk_buff *i40evf_fetch_rx_buffer(struct i40e_ring *rx_ring,

				       union i40e_rx_desc *rx_desc)

				       union i40e_rx_desc *rx_desc,

				       struct sk_buff *skb)

{

	u64 local_status_error_len =

		le64_to_cpu(rx_desc->wb.qword1.status_error_len);
@@ -1094,15 +1096,12 @@ struct sk_buff *i40evf_fetch_rx_buffer(struct i40e_ring *rx_ring, 
		(local_status_error_len & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>

		I40E_RXD_QW1_LENGTH_PBUF_SHIFT;

	struct i40e_rx_buffer *rx_buffer;

	struct sk_buff *skb;

	struct page *page;



	rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];

	page = rx_buffer->page;

	prefetchw(page);



	skb = rx_buffer->skb;



	if (likely(!skb)) {

		void *page_addr = page_address(page) + rx_buffer->page_offset;
@@ -1126,8 +1125,6 @@ struct sk_buff *i40evf_fetch_rx_buffer(struct i40e_ring *rx_ring, 
		 * it now to avoid a possible cache miss

		 */

		prefetchw(skb->data);

	} else {

		rx_buffer->skb = NULL;

	}



	/* we are reusing so sync this buffer for CPU use */
@@ -1182,8 +1179,6 @@ static bool i40e_is_non_eop(struct i40e_ring *rx_ring, 
	if (likely(i40e_test_staterr(rx_desc, I40E_RXD_EOF)))

		return false;



	/* place skb in next buffer to be received */

	rx_ring->rx_bi[ntc].skb = skb;

	rx_ring->rx_stats.non_eop_descs++;



	return true;
@@ -1204,12 +1199,12 @@ static bool i40e_is_non_eop(struct i40e_ring *rx_ring, 
static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)

{

	unsigned int total_rx_bytes = 0, total_rx_packets = 0;

	struct sk_buff *skb = rx_ring->skb;

	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);

	bool failure = false;



	while (likely(total_rx_packets < budget)) {

		union i40e_rx_desc *rx_desc;

		struct sk_buff *skb;

		u16 vlan_tag;

		u8 rx_ptype;

		u64 qword;
@@ -1238,7 +1233,7 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) 
		 */

		dma_rmb();



		skb = i40evf_fetch_rx_buffer(rx_ring, rx_desc);

		skb = i40evf_fetch_rx_buffer(rx_ring, rx_desc, skb);

		if (!skb)

			break;
@@ -1257,8 +1252,10 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) 
			continue;

		}



		if (i40e_cleanup_headers(rx_ring, skb))

		if (i40e_cleanup_headers(rx_ring, skb)) {

			skb = NULL;

			continue;

		}



		/* probably a little skewed due to removing CRC */

		total_rx_bytes += skb->len;
@@ -1275,11 +1272,14 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) 
			   le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1) : 0;



		i40e_receive_skb(rx_ring, skb, vlan_tag);

		skb = NULL;



		/* update budget accounting */

		total_rx_packets++;

	}



	rx_ring->skb = skb;



	u64_stats_update_begin(&rx_ring->syncp);

	rx_ring->stats.packets += total_rx_packets;

	rx_ring->stats.bytes += total_rx_bytes;

drivers/net/ethernet/intel/i40evf/i40e_txrx.h

+8 −1
Original line number Diff line number Diff line
@@ -239,7 +239,6 @@ struct i40e_tx_buffer { 
};



struct i40e_rx_buffer {

	struct sk_buff *skb;

	dma_addr_t dma;

	struct page *page;

	unsigned int page_offset;
@@ -340,6 +339,14 @@ struct i40e_ring { 


	struct rcu_head rcu;		/* to avoid race on free */

	u16 next_to_alloc;

	struct sk_buff *skb;		/* When i40evf_clean_rx_ring_irq() must

					 * return before it sees the EOP for

					 * the current packet, we save that skb

					 * here and resume receiving this

					 * packet the next time

					 * i40evf_clean_rx_ring_irq() is called

					 * for this ring.

					 */

} ____cacheline_internodealigned_in_smp;



enum i40e_latency_range {