From: Amritha Nambiar <amritha.nambiar@intel.com>
Date: Tue, 6 Feb 2018 13:15:20 -0800
Subject: i40e: Fix the number of queues available to be mapped for use
Patch-mainline: v4.16-rc1
Git-commit: bc6d33c8d93f5999920e97a8c6330b8910053d4f
References: bsc#1094978

Fix the number of queues per enabled TC and report available queues
to the kernel without having to limit them to the max RSS limit so
they are available to be mapped for XPS. This allows a queue per
processing thread available for handling traffic for the given
traffic class.

Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c |   27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -1776,7 +1776,7 @@ static void i40e_vsi_setup_queue_map(str
 	struct i40e_pf *pf = vsi->back;
 	u16 sections = 0;
 	u8 netdev_tc = 0;
-	u16 numtc = 0;
+	u16 numtc = 1;
 	u16 qcount;
 	u8 offset;
 	u16 qmap;
@@ -1786,9 +1786,11 @@ static void i40e_vsi_setup_queue_map(str
 	sections = I40E_AQ_VSI_PROP_QUEUE_MAP_VALID;
 	offset = 0;
 
+	/* Number of queues per enabled TC */
+	num_tc_qps = vsi->alloc_queue_pairs;
 	if (enabled_tc && (vsi->back->flags & I40E_FLAG_DCB_ENABLED)) {
 		/* Find numtc from enabled TC bitmap */
-		for (i = 0; i < I40E_MAX_TRAFFIC_CLASS; i++) {
+		for (i = 0, numtc = 0; i < I40E_MAX_TRAFFIC_CLASS; i++) {
 			if (enabled_tc & BIT(i)) /* TC is enabled */
 				numtc++;
 		}
@@ -1796,18 +1798,13 @@ static void i40e_vsi_setup_queue_map(str
 			dev_warn(&pf->pdev->dev, "DCB is enabled but no TC enabled, forcing TC0\n");
 			numtc = 1;
 		}
-	} else {
-		/* At least TC0 is enabled in non-DCB, non-MQPRIO case */
-		numtc = 1;
+		num_tc_qps = num_tc_qps / numtc;
+		num_tc_qps = min_t(int, num_tc_qps,
+				   i40e_pf_get_max_q_per_tc(pf));
 	}
 
 	vsi->tc_config.numtc = numtc;
 	vsi->tc_config.enabled_tc = enabled_tc ? enabled_tc : 1;
-	/* Number of queues per enabled TC */
-	qcount = vsi->alloc_queue_pairs;
-
-	num_tc_qps = qcount / numtc;
-	num_tc_qps = min_t(int, num_tc_qps, i40e_pf_get_max_q_per_tc(pf));
 
 	/* Do not allow use more TC queue pairs than MSI-X vectors exist */
 	if (pf->flags & I40E_FLAG_MSIX_ENABLED)
@@ -1822,9 +1819,13 @@ static void i40e_vsi_setup_queue_map(str
 
 			switch (vsi->type) {
 			case I40E_VSI_MAIN:
-				qcount = min_t(int, pf->alloc_rss_size,
-					       num_tc_qps);
-				break;
+				if (!(pf->flags & (I40E_FLAG_FD_SB_ENABLED |
+				    I40E_FLAG_FD_ATR_ENABLED)) ||
+				    vsi->tc_config.enabled_tc != 1) {
+					qcount = min_t(int, pf->alloc_rss_size,
+						       num_tc_qps);
+					break;
+				}
 			case I40E_VSI_FDIR:
 			case I40E_VSI_SRIOV:
 			case I40E_VSI_VMDQ2: