On Tue, 2014-11-18 at 17:24 -0800, Alexander Duyck wrote: > This change makes it so that dma_rmb is used when reading the Rx > descriptor. The advantage of dma_rmb is that it allows for a much > lower cost barrier on x86, powerpc, arm, and arm64 architectures than > a > traditional memory barrier when dealing with reads that only have to > synchronize to coherent memory. > > In addition I have updated the code so that it just checks to see if > any > bits have been set instead of just the DD bit since the DD bit will > always > be set as a part of a descriptor write-back so we just need to check > for a > non-zero value being present at that memory location rather than just > checking for any specific bit. This allows the code itself to appear > much > cleaner and allows the compiler more room to optimize. > > Cc: Jeff Kirsher > Cc: Matthew Vick > Cc: Don Skidmore > Signed-off-by: Alexander Duyck > --- > drivers/net/ethernet/intel/fm10k/fm10k_main.c | 6 +++--- > drivers/net/ethernet/intel/igb/igb_main.c | 6 +++--- > drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 9 ++++----- > 3 files changed, 10 insertions(+), 11 deletions(-) Acked-by: Jeff Kirsher