Skip to content

Commit

Permalink
i40e/i40evf: Moves skb from i40e_rx_buffer to i40e_ring
Browse files Browse the repository at this point in the history 
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: Scott Peterson <scott.d.peterson@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
  • Loading branch information
Scott Peterson authored and Jeff Kirsher committed Feb 12, 2017
1 parent 7987dcd commit e72e565
Show file tree
Hide file tree
Showing 4 changed files with 46 additions and 33 deletions.
31 changes: 15 additions & 16 deletions drivers/net/ethernet/intel/i40e/i40e_txrx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;

Expand Down Expand Up @@ -1608,23 +1609,21 @@ 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);
unsigned int size =
(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;

Expand All @@ -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 */
Expand Down Expand Up @@ -1702,16 +1699,13 @@ 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 */
#define I40E_RXD_EOF BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)
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;
Expand All @@ -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;
Expand Down Expand Up @@ -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;

Expand All @@ -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;
Expand All @@ -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;
Expand Down
9 changes: 8 additions & 1 deletion drivers/net/ethernet/intel/i40e/i40e_txrx.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand Down Expand Up @@ -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 {
Expand Down
30 changes: 15 additions & 15 deletions drivers/net/ethernet/intel/i40evf/i40e_txrx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;

Expand Down Expand Up @@ -1086,23 +1087,21 @@ 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);
unsigned int size =
(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;

Expand All @@ -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 */
Expand Down Expand Up @@ -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;
Expand All @@ -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;
Expand Down Expand Up @@ -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;

Expand All @@ -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;
Expand All @@ -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;
Expand Down
9 changes: 8 additions & 1 deletion drivers/net/ethernet/intel/i40evf/i40e_txrx.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand Down Expand Up @@ -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 {
Expand Down

0 comments on commit e72e565

Please sign in to comment.