xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[SK_BUFF]: Convert skb->tail to sk_buff_data_t

Browse Source 
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)

Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arnaldo Carvalho de Melo
2007-04-19 20:29:13 -07:00
committed by David S. Miller
parent be8bd86321
commit 27a884dc3c
110 changed files with 396 additions and 329 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/net/tulip/uli526x.c
View File

@@ -829,7 +829,9 @@ static void uli526x_rx_packet(struct net_device *dev, struct uli526x_board_info
!= NULL) ) {
/* size less than COPY_SIZE, allocate a rxlen SKB */
skb_reserve(skb, 2); /* 16byte align */
memcpy(skb_put(skb, rxlen), rxptr->rx_skb_ptr->tail, rxlen);
memcpy(skb_put(skb, rxlen),
skb_tail_pointer(rxptr->rx_skb_ptr),
rxlen);
uli526x_reuse_skb(db, rxptr->rx_skb_ptr);
} else
skb_put(skb, rxlen);
@@ -1175,7 +1177,10 @@ static void uli526x_reuse_skb(struct uli526x_board_info *db, struct sk_buff * sk
if (!(rxptr->rdes0 & cpu_to_le32(0x80000000))) {
rxptr->rx_skb_ptr = skb;
rxptr->rdes2 = cpu_to_le32( pci_map_single(db->pdev, skb->tail, RX_ALLOC_SIZE, PCI_DMA_FROMDEVICE) );
rxptr->rdes2 = cpu_to_le32(pci_map_single(db->pdev,
skb_tail_pointer(skb),
RX_ALLOC_SIZE,
PCI_DMA_FROMDEVICE));
wmb();
rxptr->rdes0 = cpu_to_le32(0x80000000);
db->rx_avail_cnt++;
@@ -1339,7 +1344,10 @@ static void allocate_rx_buffer(struct uli526x_board_info *db)
if ( ( skb = dev_alloc_skb(RX_ALLOC_SIZE) ) == NULL )
break;
rxptr->rx_skb_ptr = skb; /* FIXME (?) */
rxptr->rdes2 = cpu_to_le32( pci_map_single(db->pdev, skb->tail, RX_ALLOC_SIZE, PCI_DMA_FROMDEVICE) );
rxptr->rdes2 = cpu_to_le32(pci_map_single(db->pdev,
skb_tail_pointer(skb),
RX_ALLOC_SIZE,
PCI_DMA_FROMDEVICE));
wmb();
rxptr->rdes0 = cpu_to_le32(0x80000000);
rxptr = rxptr->next_rx_desc;