ice: Don't allow same value for Rx tail to be written twice

[ Upstream commit 168983a8e1 ]

Currently we compare the value we are about to write to the Rx tail
register with the previous value of next_to_use. The problem with this
is we only write tail on 8 descriptor boundaries, but next_to_use is
updated whenever we clean Rx descriptors. Fix this by comparing the
value we are about to write to tail with the previously written tail
value. This will prevent duplicate Rx tail bumps.

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Brett Creeley 2020-02-06 01:20:02 -08:00 • committed by Greg Kroah-Hartman
commit c332e75342