1. 25 5月, 2018 2 次提交
    • H
      net/dcb: Add dcbnl buffer attribute · e549f6f9
      Huy Nguyen 提交于
      In this patch, we add dcbnl buffer attribute to allow user
      change the NIC's buffer configuration such as priority
      to buffer mapping and buffer size of individual buffer.
      
      This attribute combined with pfc attribute allows advanced user to
      fine tune the qos setting for specific priority queue. For example,
      user can give dedicated buffer for one or more priorities or user
      can give large buffer to certain priorities.
      
      The dcb buffer configuration will be controlled by lldptool.
      lldptool -T -i eth2 -V BUFFER prio 0,2,5,7,1,2,3,6
        maps priorities 0,1,2,3,4,5,6,7 to receive buffer 0,2,5,7,1,2,3,6
      lldptool -T -i eth2 -V BUFFER size 87296,87296,0,87296,0,0,0,0
        sets receive buffer size for buffer 0,1,2,3,4,5,6,7 respectively
      
      After discussion on mailing list with Jakub, Jiri, Ido and John, we agreed to
      choose dcbnl over devlink interface since this feature is intended to set
      port attributes which are governed by the netdev instance of that port, where
      devlink API is more suitable for global ASIC configurations.
      
      We present an use case scenario where dcbnl buffer attribute configured
      by advance user helps reduce the latency of messages of different sizes.
      
      Scenarios description:
      On ConnectX-5, we run latency sensitive traffic with
      small/medium message sizes ranging from 64B to 256KB and bandwidth sensitive
      traffic with large messages sizes 512KB and 1MB. We group small, medium,
      and large message sizes to their own pfc enables priorities as follow.
        Priorities 1 & 2 (64B, 256B and 1KB)
        Priorities 3 & 4 (4KB, 8KB, 16KB, 64KB, 128KB and 256KB)
        Priorities 5 & 6 (512KB and 1MB)
      
      By default, ConnectX-5 maps all pfc enabled priorities to a single
      lossless fixed buffer size of 50% of total available buffer space. The
      other 50% is assigned to lossy buffer. Using dcbnl buffer attribute,
      we create three equal size lossless buffers. Each buffer has 25% of total
      available buffer space. Thus, the lossy buffer size reduces to 25%. Priority
      to lossless  buffer mappings are set as follow.
        Priorities 1 & 2 on lossless buffer #1
        Priorities 3 & 4 on lossless buffer #2
        Priorities 5 & 6 on lossless buffer #3
      
      We observe improvements in latency for small and medium message sizes
      as follows. Please note that the large message sizes bandwidth performance is
      reduced but the total bandwidth remains the same.
        256B message size (42 % latency reduction)
        4K message size (21% latency reduction)
        64K message size (16% latency reduction)
      
      CC: Ido Schimmel <idosch@idosch.org>
      CC: Jakub Kicinski <jakub.kicinski@netronome.com>
      CC: Jiri Pirko <jiri@resnulli.us>
      CC: Or Gerlitz <gerlitz.or@gmail.com>
      CC: Parav Pandit <parav@mellanox.com>
      CC: Aron Silverton <aron.silverton@oracle.com>
      Signed-off-by: NHuy Nguyen <huyn@mellanox.com>
      Reviewed-by: NParav Pandit <parav@mellanox.com>
      Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>
      e549f6f9
    • H
      net: phy: replace bool members in struct phy_device with bit-fields · 87e5808d
      Heiner Kallweit 提交于
      In struct phy_device we have a number of flags being defined as type
      bool. Similar to e.g. struct pci_dev we can save some space by using
      bit-fields.
      Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
      Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      87e5808d
  2. 24 5月, 2018 38 次提交