1. 25 Mar, 2017 2 commits
    • Saeed Mahameed's avatar
      net/mlx5e: Xmit, no write combining · 6982ab60
      Saeed Mahameed authored
      mlx5e netdev Blue Flame (write combining) support demands a lot of
      overhead for a little latency gain for some special cases, this overhead
      is hurting the common case.
      
      Here we remove xmit Blue Flame support by creating all bfregs with no
      write combining for all SQs, and we remove a lot of BF logic and
      conditions from xmit data path.
      
      Simplify mlx5e_tx_notify_hw (doorbell function) by removing BF related
      code and by removing one memory barrier needed for WC mapped SQ doorbell
      buffers, which no longer exist.
      
      Performance improvement:
      System: Intel(R) Xeon(R) CPU E5-2620 v3 @ 2.40GHz
      
      Test case                   Before      Now      improvement
      ---------------------------------------------------------------
      TX packets (24 threads)     50Mpps      54Mpps    8%
      Signed-off-by: default avatarSaeed Mahameed <saeedm@mellanox.com>
      Reviewed-by: default avatarTariq Toukan <tariqt@mellanox.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6982ab60
    • Saeed Mahameed's avatar
      net/mlx5e: Use dma_rmb rather than rmb in CQE fetch routine · 80fe326a
      Saeed Mahameed authored
      Use dma_rmb in mlx5e_get_cqe rather than aggressive rmb (at least on
      some architectures), this should help improve the performance on such
      CPU archs where dma_rmb is optimized.
      
      Performance improvement:
      System: Intel(R) Xeon(R) CPU E5-2620 v3 @ 2.40GHz
      
      Test case                   Baseline      Now      improvement
      ---------------------------------------------------------------
      TX packets (24 threads)     45Mpps        50Mpps      11%
      TC stack Drop (1 core)      3.45Mpps      3.6Mpps     5%
      XDP Drop      (1 core)      14Mpps        16.9Mpps    20%
      XDP TX        (1 core)      10.4Mpps      12Mpps      15%
      Signed-off-by: default avatarSaeed Mahameed <saeedm@mellanox.com>
      Reviewed-by: default avatarTariq Toukan <tariqt@mellanox.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      80fe326a
  2. 24 Mar, 2017 38 commits