From 7362be9eeed01980bfa03cf49737703a0e43fe50 Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Thu, 7 Sep 2017 08:05:50 -0400 Subject: [PATCH] i40e: reduce lrxqthresh from 2 to 1 The lrxq thresh value tells hardware to immediately interrupt when there are fewer than N*64 packets left in the ring. Counter intuitively, empirical testing has shown that decreasing this value from 2 to 1, and thus changing from an immediate interrupt at fewer than 128 descriptors down to 64 descriptors causes a small increase in the maximum total packets per second we can receive. This increase occurs even when we're polling with interrupts masked, as the hardware must still handle interrupts internally even if we've disabled them in software. Also reduce the value for any VFs we allocate. Signed-off-by: Jacob Keller Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/i40e/i40e_main.c | 2 +- drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index 00a83afb02e9..74875ddaeb33 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -3030,7 +3030,7 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring) if (hw->revision_id == 0) rx_ctx.lrxqthresh = 0; else - rx_ctx.lrxqthresh = 2; + rx_ctx.lrxqthresh = 1; rx_ctx.crcstrip = 1; rx_ctx.l2tsel = 1; /* this controls whether VLAN is stripped from inner headers */ diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c index 10298956a81b..83727906a386 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c +++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c @@ -639,7 +639,7 @@ static int i40e_config_vsi_rx_queue(struct i40e_vf *vf, u16 vsi_id, rx_ctx.dsize = 1; /* default values */ - rx_ctx.lrxqthresh = 2; + rx_ctx.lrxqthresh = 1; rx_ctx.crcstrip = 1; rx_ctx.prefena = 1; rx_ctx.l2tsel = 1; -- 2.30.2