[dpdk-dev] [PATCH v2] net/i40e: determine number of queues per VF during run time

[Wei Dai <wei.dai@intel.com>]

Without this patch, the number of queues per i40e  VF is defined as 4
by CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VF=4 in config/common_base.
It is fixed value determined in building time and can't be changed
during run time.
With this patch, the number of queues per i40e VF can be determinated
during run time. For example, if the PCI address of an i40e VF is
aaaa:bb.cc, with the EAL parameter -w aaaa:bb.cc,i40e-queue-num-per-vf=8
, the number of queues per VF is 8.
If there is no "i40e-queue-num-per-vf" setting in EAL parameters,
it is 4 by default as before. And if the value after the
"i40e-queue-num-per-vf" is invalid, it is set as 4 forcibly.
The valid values include 1, 2, 4, 8, 16 .

Signed-off-by: Wei Dai <wei.dai@intel.com>

---
v2: fix WARNING of coding style issues from checkpatch@dpdk.org
---
 config/common_base             |  1 -
 drivers/net/i40e/i40e_ethdev.c | 68 ++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 66 insertions(+), 3 deletions(-)

diff --git a/config/common_base b/config/common_base
index e74febe..4e20389 100644
--- a/config/common_base
+++ b/config/common_base
@@ -208,7 +208,6 @@ CONFIG_RTE_LIBRTE_I40E_RX_ALLOW_BULK_ALLOC=y
 CONFIG_RTE_LIBRTE_I40E_INC_VECTOR=y
 CONFIG_RTE_LIBRTE_I40E_16BYTE_RX_DESC=n
 CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_PF=64
-CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VF=4
 CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VM=4
 # interval up to 8160 us, aligned to 2 (or default value)
 CONFIG_RTE_LIBRTE_I40E_ITR_INTERVAL=-1
diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index 811cc9f..5b8c309 100644
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -3971,6 +3971,68 @@ i40e_get_cap(struct i40e_hw *hw)
 	return ret;
 }
 
+static int i40e_pf_config_vf_rxq_number(struct rte_eth_dev *dev)
+{
+#define RTE_LIBRTE_I40E_QUEUE_NUM_PER_VF	4
+#define I40E_QUEUE_NUM_PER_VF_ARG		"i40e-queue-num-per-vf"
+#define IS_POWER_OF_2(n)			((n) && !((n) & ((n) - 1)))
+
+	struct i40e_pf *pf = I40E_DEV_PRIVATE_TO_PF(dev->data->dev_private);
+	char *s;
+	char *ps0, *ps1, *pv;
+	char *end;
+	unsigned long value;
+
+	if (!is_i40e_supported(dev))
+		return -ENOTSUP;
+
+	/* set default queue number per VF as 4 */
+	pf->vf_nb_qp_max = RTE_LIBRTE_I40E_QUEUE_NUM_PER_VF;
+
+	if (dev->device->devargs == NULL)
+		return 0;
+
+	s = rte_zmalloc(__func__, strlen(dev->device->devargs->args) + 1, 0);
+	if (s == NULL)
+		return -(ENOMEM);
+	strcpy(s, dev->device->devargs->args);
+
+	ps0 = s;
+	do {
+		while (isblank(*ps0))
+			ps0++;
+		pv = strchr(ps0, '=');
+		if (pv == NULL)
+			break;
+		ps1 = pv - 1;
+		*pv++ = 0;
+
+		while (isblank(*ps1))
+			*ps1-- = 0;
+
+		if (!strcmp(ps0, I40E_QUEUE_NUM_PER_VF_ARG)) {
+			errno = 0;
+			value = strtoul(pv, &end, 0);
+			if (errno != 0 || end == pv)
+				break;
+			if (value <= 16 && IS_POWER_OF_2(value))
+				pf->vf_nb_qp_max = (uint16_t)value;
+			else
+				PMD_DRV_LOG(ERR, "Wrong VF queue number = %lu,"
+					" it must be power of 2 and equal or"
+					" less than 16 !", value);
+			break;
+		}
+		ps0 = strchr(pv, ',');
+		if (ps0 == NULL)
+			break;
+		ps0++;
+	} while (1);
+
+	rte_free(s);
+	return 0;
+}
+
 static int
 i40e_pf_parameter_init(struct rte_eth_dev *dev)
 {
@@ -3983,6 +4045,9 @@ i40e_pf_parameter_init(struct rte_eth_dev *dev)
 		PMD_INIT_LOG(ERR, "HW configuration doesn't support SRIOV");
 		return -EINVAL;
 	}
+
+	i40e_pf_config_vf_rxq_number(dev);
+
 	/* Add the parameter init for LFC */
 	pf->fc_conf.pause_time = I40E_DEFAULT_PAUSE_TIME;
 	pf->fc_conf.high_water[I40E_MAX_TRAFFIC_CLASS] = I40E_DEFAULT_HIGH_WATER;
@@ -3992,7 +4057,6 @@ i40e_pf_parameter_init(struct rte_eth_dev *dev)
 	pf->max_num_vsi = hw->func_caps.num_vsis;
 	pf->lan_nb_qp_max = RTE_LIBRTE_I40E_QUEUE_NUM_PER_PF;
 	pf->vmdq_nb_qp_max = RTE_LIBRTE_I40E_QUEUE_NUM_PER_VM;
-	pf->vf_nb_qp_max = RTE_LIBRTE_I40E_QUEUE_NUM_PER_VF;
 
 	/* FDir queue/VSI allocation */
 	pf->fdir_qp_offset = 0;
@@ -4022,7 +4086,7 @@ i40e_pf_parameter_init(struct rte_eth_dev *dev)
 	pf->vf_qp_offset = pf->lan_qp_offset + pf->lan_nb_qps;
 	if (hw->func_caps.sr_iov_1_1 && pci_dev->max_vfs) {
 		pf->flags |= I40E_FLAG_SRIOV;
-		pf->vf_nb_qps = RTE_LIBRTE_I40E_QUEUE_NUM_PER_VF;
+		pf->vf_nb_qps = pf->vf_nb_qp_max;
 		pf->vf_num = pci_dev->max_vfs;
 		PMD_DRV_LOG(DEBUG,
 			"%u VF VSIs, %u queues per VF VSI, in total %u queues",
-- 
2.7.5