Skip to content

Commit

Permalink
igb: drop support for single buffer mode
Browse files Browse the repository at this point in the history 
This change removes support for single buffer mode from igb and makes the
driver function in packet split always.  The advantage to doing this is
that we can reduce total memory allocation overhead significantly as we
will only need to allocate one 1K slab per packet and then make use of a
reusable half page instead of allocating a 2K slab per packet.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by:  Aaron Brown  <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
  • Loading branch information
Alexander Duyck authored and Jeff Kirsher committed Sep 20, 2011
1 parent 153285f commit 44390ca
Show file tree
Hide file tree
Showing 3 changed files with 28 additions and 86 deletions.
7 changes: 2 additions & 5 deletions drivers/net/ethernet/intel/igb/igb.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -111,11 +111,9 @@ struct vf_data_storage {
#define MAXIMUM_ETHERNET_VLAN_SIZE 1522

/* Supported Rx Buffer Sizes */
#define IGB_RXBUFFER_64 64 /* Used for packet split */
#define IGB_RXBUFFER_128 128 /* Used for packet split */
#define IGB_RXBUFFER_1024 1024
#define IGB_RXBUFFER_2048 2048
#define IGB_RXBUFFER_512 512
#define IGB_RXBUFFER_16384 16384
#define IGB_RX_HDR_LEN IGB_RXBUFFER_512

/* How many Tx Descriptors do we need to call netif_wake_queue ? */
#define IGB_TX_QUEUE_WAKE 16
Expand Down Expand Up @@ -221,7 +219,6 @@ struct igb_ring {
struct {
struct igb_rx_queue_stats rx_stats;
struct u64_stats_sync rx_syncp;
u32 rx_buffer_len;
};
};
};
Expand Down
5 changes: 2 additions & 3 deletions drivers/net/ethernet/intel/igb/igb_ethtool.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1368,7 +1368,6 @@ static int igb_setup_desc_rings(struct igb_adapter *adapter)
rx_ring->count = IGB_DEFAULT_RXD;
rx_ring->dev = &adapter->pdev->dev;
rx_ring->netdev = adapter->netdev;
rx_ring->rx_buffer_len = IGB_RXBUFFER_2048;
rx_ring->reg_idx = adapter->vfs_allocated_count;

if (igb_setup_rx_resources(rx_ring)) {
Expand Down Expand Up @@ -1597,7 +1596,7 @@ static int igb_clean_test_rings(struct igb_ring *rx_ring,
/* unmap rx buffer, will be remapped by alloc_rx_buffers */
dma_unmap_single(rx_ring->dev,
buffer_info->dma,
rx_ring->rx_buffer_len,
IGB_RX_HDR_LEN,
DMA_FROM_DEVICE);
buffer_info->dma = 0;

Expand Down Expand Up @@ -1635,7 +1634,7 @@ static int igb_run_loopback_test(struct igb_adapter *adapter)
struct igb_ring *tx_ring = &adapter->test_tx_ring;
struct igb_ring *rx_ring = &adapter->test_rx_ring;
int i, j, lc, good_cnt, ret_val = 0;
unsigned int size = 1024;
unsigned int size = IGB_RX_HDR_LEN;
netdev_tx_t tx_ret_val;
struct sk_buff *skb;

Expand Down
102 changes: 24 additions & 78 deletions drivers/net/ethernet/intel/igb/igb_main.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -517,16 +517,14 @@ static void igb_dump(struct igb_adapter *adapter)
DUMP_PREFIX_ADDRESS,
16, 1,
phys_to_virt(buffer_info->dma),
rx_ring->rx_buffer_len, true);
if (rx_ring->rx_buffer_len
< IGB_RXBUFFER_1024)
print_hex_dump(KERN_INFO, "",
DUMP_PREFIX_ADDRESS,
16, 1,
phys_to_virt(
buffer_info->page_dma +
buffer_info->page_offset),
PAGE_SIZE/2, true);
IGB_RX_HDR_LEN, true);
print_hex_dump(KERN_INFO, "",
DUMP_PREFIX_ADDRESS,
16, 1,
phys_to_virt(
buffer_info->page_dma +
buffer_info->page_offset),
PAGE_SIZE/2, true);
}
}

Expand Down Expand Up @@ -707,7 +705,6 @@ static int igb_alloc_queues(struct igb_adapter *adapter)
ring->queue_index = i;
ring->dev = &adapter->pdev->dev;
ring->netdev = adapter->netdev;
ring->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
ring->flags = IGB_RING_FLAG_RX_CSUM; /* enable rx checksum */
/* set flag indicating ring supports SCTP checksum offload */
if (adapter->hw.mac.type >= e1000_82576)
Expand Down Expand Up @@ -3049,22 +3046,13 @@ void igb_configure_rx_ring(struct igb_adapter *adapter,
writel(0, ring->tail);

/* set descriptor configuration */
if (ring->rx_buffer_len < IGB_RXBUFFER_1024) {
srrctl = ALIGN(ring->rx_buffer_len, 64) <<
E1000_SRRCTL_BSIZEHDRSIZE_SHIFT;
srrctl = IGB_RX_HDR_LEN << E1000_SRRCTL_BSIZEHDRSIZE_SHIFT;
#if (PAGE_SIZE / 2) > IGB_RXBUFFER_16384
srrctl |= IGB_RXBUFFER_16384 >>
E1000_SRRCTL_BSIZEPKT_SHIFT;
srrctl |= IGB_RXBUFFER_16384 >> E1000_SRRCTL_BSIZEPKT_SHIFT;
#else
srrctl |= (PAGE_SIZE / 2) >>
E1000_SRRCTL_BSIZEPKT_SHIFT;
srrctl |= (PAGE_SIZE / 2) >> E1000_SRRCTL_BSIZEPKT_SHIFT;
#endif
srrctl |= E1000_SRRCTL_DESCTYPE_HDR_SPLIT_ALWAYS;
} else {
srrctl = ALIGN(ring->rx_buffer_len, 1024) >>
E1000_SRRCTL_BSIZEPKT_SHIFT;
srrctl |= E1000_SRRCTL_DESCTYPE_ADV_ONEBUF;
}
srrctl |= E1000_SRRCTL_DESCTYPE_HDR_SPLIT_ALWAYS;
if (hw->mac.type == e1000_82580)
srrctl |= E1000_SRRCTL_TIMESTAMP;
/* Only set Drop Enable if we are supporting multiple queues */
Expand Down Expand Up @@ -3268,7 +3256,7 @@ static void igb_clean_rx_ring(struct igb_ring *rx_ring)
if (buffer_info->dma) {
dma_unmap_single(rx_ring->dev,
buffer_info->dma,
rx_ring->rx_buffer_len,
IGB_RX_HDR_LEN,
DMA_FROM_DEVICE);
buffer_info->dma = 0;
}
Expand Down Expand Up @@ -4466,7 +4454,6 @@ static int igb_change_mtu(struct net_device *netdev, int new_mtu)
struct igb_adapter *adapter = netdev_priv(netdev);
struct pci_dev *pdev = adapter->pdev;
int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
u32 rx_buffer_len, i;

if ((new_mtu < 68) || (max_frame > MAX_JUMBO_FRAME_SIZE)) {
dev_err(&pdev->dev, "Invalid MTU setting\n");
Expand All @@ -4485,40 +4472,13 @@ static int igb_change_mtu(struct net_device *netdev, int new_mtu)
/* igb_down has a dependency on max_frame_size */
adapter->max_frame_size = max_frame;

/* NOTE: netdev_alloc_skb reserves 16 bytes, and typically NET_IP_ALIGN
* means we reserve 2 more, this pushes us to allocate from the next
* larger slab size.
* i.e. RXBUFFER_2048 --> size-4096 slab
*/

if (adapter->hw.mac.type == e1000_82580)
max_frame += IGB_TS_HDR_LEN;

if (max_frame <= IGB_RXBUFFER_1024)
rx_buffer_len = IGB_RXBUFFER_1024;
else if (max_frame <= MAXIMUM_ETHERNET_VLAN_SIZE)
rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
else
rx_buffer_len = IGB_RXBUFFER_128;

if ((max_frame == ETH_FRAME_LEN + ETH_FCS_LEN + IGB_TS_HDR_LEN) ||
(max_frame == MAXIMUM_ETHERNET_VLAN_SIZE + IGB_TS_HDR_LEN))
rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE + IGB_TS_HDR_LEN;

if ((adapter->hw.mac.type == e1000_82580) &&
(rx_buffer_len == IGB_RXBUFFER_128))
rx_buffer_len += IGB_RXBUFFER_64;

if (netif_running(netdev))
igb_down(adapter);

dev_info(&pdev->dev, "changing MTU from %d to %d\n",
netdev->mtu, new_mtu);
netdev->mtu = new_mtu;

for (i = 0; i < adapter->num_rx_queues; i++)
adapter->rx_ring[i]->rx_buffer_len = rx_buffer_len;

if (netif_running(netdev))
igb_up(adapter);
else
Expand Down Expand Up @@ -5781,17 +5741,16 @@ static void igb_rx_hwtstamp(struct igb_q_vector *q_vector, u32 staterr,

igb_systim_to_hwtstamp(adapter, skb_hwtstamps(skb), regval);
}
static inline u16 igb_get_hlen(struct igb_ring *rx_ring,
union e1000_adv_rx_desc *rx_desc)
static inline u16 igb_get_hlen(union e1000_adv_rx_desc *rx_desc)
{
/* HW will not DMA in data larger than the given buffer, even if it
* parses the (NFS, of course) header to be larger. In that case, it
* fills the header buffer and spills the rest into the page.
*/
u16 hlen = (le16_to_cpu(rx_desc->wb.lower.lo_dword.hdr_info) &
E1000_RXDADV_HDRBUFLEN_MASK) >> E1000_RXDADV_HDRBUFLEN_SHIFT;
if (hlen > rx_ring->rx_buffer_len)
hlen = rx_ring->rx_buffer_len;
if (hlen > IGB_RX_HDR_LEN)
hlen = IGB_RX_HDR_LEN;
return hlen;
}

Expand Down Expand Up @@ -5841,14 +5800,10 @@ static bool igb_clean_rx_irq_adv(struct igb_q_vector *q_vector,

if (buffer_info->dma) {
dma_unmap_single(dev, buffer_info->dma,
rx_ring->rx_buffer_len,
IGB_RX_HDR_LEN,
DMA_FROM_DEVICE);
buffer_info->dma = 0;
if (rx_ring->rx_buffer_len >= IGB_RXBUFFER_1024) {
skb_put(skb, length);
goto send_up;
}
skb_put(skb, igb_get_hlen(rx_ring, rx_desc));
skb_put(skb, igb_get_hlen(rx_desc));
}

if (length) {
Expand Down Expand Up @@ -5879,7 +5834,7 @@ static bool igb_clean_rx_irq_adv(struct igb_q_vector *q_vector,
next_buffer->dma = 0;
goto next_desc;
}
send_up:

if (staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) {
dev_kfree_skb_irq(skb);
goto next_desc;
Expand Down Expand Up @@ -5943,17 +5898,14 @@ void igb_alloc_rx_buffers_adv(struct igb_ring *rx_ring, int cleaned_count)
struct igb_buffer *buffer_info;
struct sk_buff *skb;
unsigned int i;
int bufsz;

i = rx_ring->next_to_use;
buffer_info = &rx_ring->buffer_info[i];

bufsz = rx_ring->rx_buffer_len;

while (cleaned_count--) {
rx_desc = E1000_RX_DESC_ADV(*rx_ring, i);

if ((bufsz < IGB_RXBUFFER_1024) && !buffer_info->page_dma) {
if (!buffer_info->page_dma) {
if (!buffer_info->page) {
buffer_info->page = netdev_alloc_page(netdev);
if (unlikely(!buffer_info->page)) {
Expand Down Expand Up @@ -5983,7 +5935,7 @@ void igb_alloc_rx_buffers_adv(struct igb_ring *rx_ring, int cleaned_count)

skb = buffer_info->skb;
if (!skb) {
skb = netdev_alloc_skb_ip_align(netdev, bufsz);
skb = netdev_alloc_skb_ip_align(netdev, IGB_RX_HDR_LEN);
if (unlikely(!skb)) {
u64_stats_update_begin(&rx_ring->rx_syncp);
rx_ring->rx_stats.alloc_failed++;
Expand All @@ -5996,7 +5948,7 @@ void igb_alloc_rx_buffers_adv(struct igb_ring *rx_ring, int cleaned_count)
if (!buffer_info->dma) {
buffer_info->dma = dma_map_single(rx_ring->dev,
skb->data,
bufsz,
IGB_RX_HDR_LEN,
DMA_FROM_DEVICE);
if (dma_mapping_error(rx_ring->dev,
buffer_info->dma)) {
Expand All @@ -6009,14 +5961,8 @@ void igb_alloc_rx_buffers_adv(struct igb_ring *rx_ring, int cleaned_count)
}
/* Refresh the desc even if buffer_addrs didn't change because
* each write-back erases this info. */
if (bufsz < IGB_RXBUFFER_1024) {
rx_desc->read.pkt_addr =
cpu_to_le64(buffer_info->page_dma);
rx_desc->read.hdr_addr = cpu_to_le64(buffer_info->dma);
} else {
rx_desc->read.pkt_addr = cpu_to_le64(buffer_info->dma);
rx_desc->read.hdr_addr = 0;
}
rx_desc->read.pkt_addr = cpu_to_le64(buffer_info->page_dma);
rx_desc->read.hdr_addr = cpu_to_le64(buffer_info->dma);

i++;
if (i == rx_ring->count)
Expand Down

0 comments on commit 44390ca

Please sign in to comment.