1. 18 5月, 2018 1 次提交
  2. 17 5月, 2018 1 次提交
  3. 28 4月, 2018 1 次提交
  4. 25 4月, 2018 7 次提交
  5. 17 4月, 2018 4 次提交
    • J
      xdp: transition into using xdp_frame for ndo_xdp_xmit · 44fa2dbd
      Jesper Dangaard Brouer 提交于
      Changing API ndo_xdp_xmit to take a struct xdp_frame instead of struct
      xdp_buff.  This brings xdp_return_frame and ndp_xdp_xmit in sync.
      
      This builds towards changing the API further to become a bulk API,
      because xdp_buff is not a queue-able object while xdp_frame is.
      
      V4: Adjust for commit 59655a5b ("tuntap: XDP_TX can use native XDP")
      V7: Adjust for commit d9314c47 ("i40e: add support for XDP_REDIRECT")
      Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      44fa2dbd
    • J
      xdp: transition into using xdp_frame for return API · 03993094
      Jesper Dangaard Brouer 提交于
      Changing API xdp_return_frame() to take struct xdp_frame as argument,
      seems like a natural choice. But there are some subtle performance
      details here that needs extra care, which is a deliberate choice.
      
      When de-referencing xdp_frame on a remote CPU during DMA-TX
      completion, result in the cache-line is change to "Shared"
      state. Later when the page is reused for RX, then this xdp_frame
      cache-line is written, which change the state to "Modified".
      
      This situation already happens (naturally) for, virtio_net, tun and
      cpumap as the xdp_frame pointer is the queued object.  In tun and
      cpumap, the ptr_ring is used for efficiently transferring cache-lines
      (with pointers) between CPUs. Thus, the only option is to
      de-referencing xdp_frame.
      
      It is only the ixgbe driver that had an optimization, in which it can
      avoid doing the de-reference of xdp_frame.  The driver already have
      TX-ring queue, which (in case of remote DMA-TX completion) have to be
      transferred between CPUs anyhow.  In this data area, we stored a
      struct xdp_mem_info and a data pointer, which allowed us to avoid
      de-referencing xdp_frame.
      
      To compensate for this, a prefetchw is used for telling the cache
      coherency protocol about our access pattern.  My benchmarks show that
      this prefetchw is enough to compensate the ixgbe driver.
      
      V7: Adjust for commit d9314c47 ("i40e: add support for XDP_REDIRECT")
      V8: Adjust for commit bd658dda ("net/mlx5e: Separate dma base address
      and offset in dma_sync call")
      Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      03993094
    • J
      xdp: rhashtable with allocator ID to pointer mapping · 8d5d8852
      Jesper Dangaard Brouer 提交于
      Use the IDA infrastructure for getting a cyclic increasing ID number,
      that is used for keeping track of each registered allocator per
      RX-queue xdp_rxq_info.  Instead of using the IDR infrastructure, which
      uses a radix tree, use a dynamic rhashtable, for creating ID to
      pointer lookup table, because this is faster.
      
      The problem that is being solved here is that, the xdp_rxq_info
      pointer (stored in xdp_buff) cannot be used directly, as the
      guaranteed lifetime is too short.  The info is needed on a
      (potentially) remote CPU during DMA-TX completion time . In an
      xdp_frame the xdp_mem_info is stored, when it got converted from an
      xdp_buff, which is sufficient for the simple page refcnt based recycle
      schemes.
      
      For more advanced allocators there is a need to store a pointer to the
      registered allocator.  Thus, there is a need to guard the lifetime or
      validity of the allocator pointer, which is done through this
      rhashtable ID map to pointer. The removal and validity of of the
      allocator and helper struct xdp_mem_allocator is guarded by RCU.  The
      allocator will be created by the driver, and registered with
      xdp_rxq_info_reg_mem_model().
      
      It is up-to debate who is responsible for freeing the allocator
      pointer or invoking the allocator destructor function.  In any case,
      this must happen via RCU freeing.
      
      Use the IDA infrastructure for getting a cyclic increasing ID number,
      that is used for keeping track of each registered allocator per
      RX-queue xdp_rxq_info.
      
      V4: Per req of Jason Wang
      - Use xdp_rxq_info_reg_mem_model() in all drivers implementing
        XDP_REDIRECT, even-though it's not strictly necessary when
        allocator==NULL for type MEM_TYPE_PAGE_SHARED (given it's zero).
      
      V6: Per req of Alex Duyck
      - Introduce rhashtable_lookup() call in later patch
      
      V8: Address sparse should be static warnings (from kbuild test robot)
      Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      8d5d8852
    • J
      ixgbe: use xdp_return_frame API · 189ead81
      Jesper Dangaard Brouer 提交于
      Extend struct ixgbe_tx_buffer to store the xdp_mem_info.
      
      Notice that this could be optimized further by putting this into
      a union in the struct ixgbe_tx_buffer, but this patchset
      works towards removing this again.  Thus, this is not done.
      Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      189ead81
  6. 24 3月, 2018 5 次提交
  7. 27 2月, 2018 2 次提交
  8. 27 1月, 2018 2 次提交
  9. 26 1月, 2018 1 次提交
  10. 24 1月, 2018 7 次提交
  11. 13 1月, 2018 8 次提交
  12. 10 1月, 2018 1 次提交