i40e: Fix the number of queues available to be mapped for use

Web:        https://git.kernel.org/torvalds/c/bc6d33c8d93f5999920e97a8c6330b8910053d4f
Commit:     bc6d33c8d93f5999920e97a8c6330b8910053d4f
Parent:     44750f8483a1bc4bda58ec4f7b7af5b053833d49
Refname:    refs/heads/master
Author:     Amritha Nambiar <[email protected]>
AuthorDate: Tue Feb 6 13:15:20 2018 -0800
Committer:  David S. Miller <[email protected]>
CommitDate: Wed Feb 7 21:53:32 2018 -0500

    i40e: Fix the number of queues available to be mapped for use
    
    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 <[email protected]>
    Tested-by: Andrew Bowers <[email protected]>
    Signed-off-by: Jeff Kirsher <[email protected]>
    Signed-off-by: David S. Miller <[email protected]>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index f95ce9b5e4fb..e31adbc75f9c 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -1785,7 +1785,7 @@ static void i40e_vsi_setup_queue_map(struct i40e_vsi *vsi,
 	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;
@@ -1795,9 +1795,11 @@ static void i40e_vsi_setup_queue_map(struct i40e_vsi *vsi,
 	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++;
 		}
@@ -1805,18 +1807,13 @@ static void i40e_vsi_setup_queue_map(struct i40e_vsi *vsi,
 			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;