1. 07 5月, 2010 4 次提交
  2. 06 5月, 2010 35 次提交
  3. 05 5月, 2010 1 次提交
    • E
      net: __alloc_skb() speedup · ec7d2f2c
      Eric Dumazet 提交于
      With following patch I can reach maximum rate of my pktgen+udpsink
      simulator :
      - 'old' machine : dual quad core E5450  @3.00GHz
      - 64 UDP rx flows (only differ by destination port)
      - RPS enabled, NIC interrupts serviced on cpu0
      - rps dispatched on 7 other cores. (~130.000 IPI per second)
      - SLAB allocator (faster than SLUB in this workload)
      - tg3 NIC
      - 1.080.000 pps without a single drop at NIC level.
      
      Idea is to add two prefetchw() calls in __alloc_skb(), one to prefetch
      first sk_buff cache line, the second to prefetch the shinfo part.
      
      Also using one memset() to initialize all skb_shared_info fields instead
      of one by one to reduce number of instructions, using long word moves.
      
      All skb_shared_info fields before 'dataref' are cleared in 
      __alloc_skb().
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ec7d2f2c