[dpdk-dev] [RFC 2/2] net/i40e: update requested queue pair num check for rounding

[Kevin Traynor <ktraynor@redhat.com>]

Since rounding up the requested queue pairs to allow the vf to
request a non-aligned number was added, it may happen that the
requested number is less than the available num of queues but the
rounded up number is greater. In this case, it is not caught with
the usual checks but later when there is a reset and failed setup.

By rounding earlier the checks can be done before a failed reset
occurs, and a rounded max amount of available queues can be returned
to the vf.

Cc: zhirun.yan@intel.com
Signed-off-by: Kevin Traynor <ktraynor@redhat.com>
---
 drivers/net/i40e/i40e_pf.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/net/i40e/i40e_pf.c b/drivers/net/i40e/i40e_pf.c
index 0c4bdbcd1..651c56bb2 100644
--- a/drivers/net/i40e/i40e_pf.c
+++ b/drivers/net/i40e/i40e_pf.c
@@ -1251,4 +1251,7 @@ i40e_pf_host_process_cmd_request_queues(struct i40e_pf_vf *vf, uint8_t *msg)
 	pf = vf->pf;
 
+	if (!rte_is_power_of_2(req_pairs))
+		req_pairs = i40e_align_floor(req_pairs) << 1;
+
 	if (req_pairs == 0) {
 		PMD_DRV_LOG(ERR, "VF %d tried to request 0 queues. Ignoring.\n",
@@ -1261,17 +1264,16 @@ i40e_pf_host_process_cmd_request_queues(struct i40e_pf_vf *vf, uint8_t *msg)
 		vfres->num_queue_pairs = I40E_MAX_QP_NUM_PER_VF;
 	} else if (req_pairs > cur_pairs + pf->qp_pool.num_free) {
-		PMD_DRV_LOG(ERR,
-			    "VF %d requested %d more queues, but only %d left\n",
+		PMD_DRV_LOG(ERR, "VF %d requested %d queues (rounded to %d) "
+			         "but only %d available\n",
 			    vf->vf_idx,
-			    req_pairs - cur_pairs,
-			    pf->qp_pool.num_free);
-		vfres->num_queue_pairs = pf->qp_pool.num_free + cur_pairs;
+			    vfres->num_queue_pairs,
+			    req_pairs,
+			    cur_pairs + pf->qp_pool.num_free);
+		vfres->num_queue_pairs = i40e_align_floor(pf->qp_pool.num_free +
+			                                  cur_pairs);
 	} else {
 		i40e_vc_notify_vf_reset(vf);
 		vf->vsi->nb_qps = req_pairs;
-		if (rte_is_power_of_2(req_pairs))
-			pf->vf_nb_qps = req_pairs;
-		else
-			pf->vf_nb_qps = i40e_align_floor(req_pairs) << 1;
+		pf->vf_nb_qps = req_pairs;
 		i40e_pf_host_process_cmd_reset_vf(vf);
 
-- 
2.20.1