offsetof(struct net_device, features)=0x44 offsetof(struct net_device, stats.tx_packets)=0x54 offsetof(struct net_device, stats.tx_bytes)=0x5c offsetof(struct net_device, stats.tx_dropped)=0x6c Network drivers that touch dev->stats.tx_packets/stats.tx_bytes in their tx path can slow down SMP operations, since they dirty a cache line that should stay shared (dev->features is needed in rx and tx paths) We could move away stats field in net_device but it wont help that much. (Two cache lines dirtied in tx path, we can do one only) Better solution is to add tx_packets/tx_bytes/tx_dropped in struct netdev_queue because this structure is already touched in tx path and counters updates will then be free (no increase in size) 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 | ||