Commit e954b374 authored Feb 08, 2012 by Alexander Duyck Committed by Jeff Kirsher Mar 12, 2012

ixgbe: Address issues with Tx WHTRESH value not being set correctly

This change is meant to address the fact that the tx_itr_setting was
dropping to 0 when no separate Tx vectors were provided. This had resulted
in the driver incorrectly configuring the Tx ring with a WTHRESH of 1 in
order to avoid Tx hangs even though that was not necessary. This change
makes it so that we instead take a look at the Tx ring's q_vector to
determine if the ring will have an ITR value less than 8us.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Stephen Ko <stephen.s.ko@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

parent 46646e61

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -2595,12 +2595,15 @@ void ixgbe_configure_tx_ring(struct ixgbe_adapter *adapter,
		* to or less than the number of on chip descriptors, which is
		* currently 40.
		*/
		if (!adapter->tx_itr_setting \|\| !adapter->rx_itr_setting)
		if (!ring->q_vector \|\| (ring->q_vector->itr < 8))
		txdctl \|= (1 << 16); /* WTHRESH = 1 */
		else
		txdctl \|= (8 << 16); /* WTHRESH = 8 */

		/* PTHRESH=32 is needed to avoid a Tx hang with DFP enabled. */
		/*
		* Setting PTHRESH to 32 both improves performance
		* and avoids a TX hang with DFP enabled
		*/
		txdctl \|= (1 << 8) \| /* HTHRESH = 1 */
		32; /* PTHRESH = 32 */