9d21493b4b
struct net_device trans_start field is a hot spot on SMP and high performance devices, particularly multi queues ones, because every transmitter dirties it. Is main use is tx watchdog and bonding alive checks. But as most devices dont use NETIF_F_LLTX, we have to lock a netdev_queue before calling their ndo_start_xmit(). So it makes sense to move trans_start from net_device to netdev_queue. Its update will occur on a already present (and in exclusive state) cache line, for free. We can do this transition smoothly. An old driver continue to update dev->trans_start, while an updated one updates txq->trans_start. Further patches could also put tx_bytes/tx_packets counters in netdev_queue to avoid dirtying dev->stats (vlan device comes to mind) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| acpi | ||
| asm-arm | ||
| asm-generic | ||
| asm-h8300 | ||
| asm-m32r | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| trace | ||
| video | ||
| xen | ||
| Kbuild | ||