On Mon, 2014-11-17 at 09:18 -0800, Alexander Duyck wrote:

This change makes it so that fast_rmb is used when reading the Rx
descriptor.  The advantage of fast_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 system 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 <redacted>
Cc: Matthew Vick <redacted>
Cc: Don Skidmore <redacted>
Signed-off-by: Alexander Duyck <redacted>
---
 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(-)

Looks like more changes will be coming, based on the feedback on earlier
patches.  So I won't be picking this up for validation purposes.