1. 19 7月, 2011 2 次提交
    • M
      vhost: vhost TX zero-copy support · bab632d6
      Michael S. Tsirkin 提交于
      >From: Shirley Ma <mashirle@us.ibm.com>
      
      This adds experimental zero copy support in vhost-net,
      disabled by default. To enable, set
      experimental_zcopytx module option to 1.
      
      This patch maintains the outstanding userspace buffers in the
      sequence it is delivered to vhost. The outstanding userspace buffers
      will be marked as done once the lower device buffers DMA has finished.
      This is monitored through last reference of kfree_skb callback. Two
      buffer indices are used for this purpose.
      
      The vhost-net device passes the userspace buffers info to lower device
      skb through message control. DMA done status check and guest
      notification are handled by handle_tx: in the worst case is all buffers
      in the vq are in pending/done status, so we need to notify guest to
      release DMA done buffers first before we get any new buffers from the
      vq.
      
      One known problem is that if the guest stops submitting
      buffers, buffers might never get used until some
      further action, e.g. device reset. This does not
      seem to affect linux guests.
      Signed-off-by: NShirley <xma@us.ibm.com>
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bab632d6
    • E
      ipv4: save cpu cycles from check_leaf() · 5c74501f
      Eric Dumazet 提交于
      Compiler is not smart enough to avoid double BSWAP instructions in
      ntohl(inet_make_mask(plen)).
      
      Lets cache this value in struct leaf_info, (fill a hole on 64bit arches)
      
      With route cache disabled, this saves ~2% of cpu in udpflood bench on
      x86_64 machine.
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5c74501f
  2. 18 7月, 2011 6 次提交
  3. 17 7月, 2011 10 次提交
  4. 15 7月, 2011 22 次提交