Re: [intel-next 1/2] net/i40e: link NAPI instances to queues and IRQs
From: Nambiar, Amritha
Date: Wed Apr 10 2024 - 05:13:20 EST
On 4/9/2024 9:39 PM, Joe Damato wrote:
Make i40e compatible with the newly added netlink queue GET APIs.
$ ./cli.py --spec ../../../Documentation/netlink/specs/netdev.yaml \
--do queue-get --json '{"ifindex": 3, "id": 1, "type": "rx"}'
{'id': 1, 'ifindex': 3, 'napi-id': 162, 'type': 'rx'}
$ ./cli.py --spec ../../../Documentation/netlink/specs/netdev.yaml \
--do napi-get --json '{"id": 162}'
{'id': 162, 'ifindex': 3, 'irq': 136}
The above output suggests that irq 136 was allocated for queue 1, which has
a NAPI ID of 162.
To double check this is correct, the IRQ to queue mapping can be verified
by checking /proc/interrupts:
$ cat /proc/interrupts | grep 136\: | \
awk '{print "irq: " $1 " name " $76}'
irq: 136: name i40e-vlan300-TxRx-1
Suggests that queue 1 has IRQ 136, as expected.
Signed-off-by: Joe Damato <jdamato@xxxxxxxxxx>
---
drivers/net/ethernet/intel/i40e/i40e.h | 2 +
drivers/net/ethernet/intel/i40e/i40e_main.c | 58 +++++++++++++++++++++
drivers/net/ethernet/intel/i40e/i40e_txrx.c | 4 ++
3 files changed, 64 insertions(+)
diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 2fbabcdb5bb5..5900ed5c7170 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -1267,6 +1267,8 @@ int i40e_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd);
int i40e_open(struct net_device *netdev);
int i40e_close(struct net_device *netdev);
int i40e_vsi_open(struct i40e_vsi *vsi);
+void i40e_queue_set_napi(struct i40e_vsi *vsi, unsigned int queue_index,
+ enum netdev_queue_type type, struct napi_struct *napi);
void i40e_vlan_stripping_disable(struct i40e_vsi *vsi);
int i40e_add_vlan_all_mac(struct i40e_vsi *vsi, s16 vid);
int i40e_vsi_add_vlan(struct i40e_vsi *vsi, u16 vid);
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 0bdcdea0be3e..6384a0c73a05 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -3448,6 +3448,58 @@ static struct xsk_buff_pool *i40e_xsk_pool(struct i40e_ring *ring)
return xsk_get_pool_from_qid(ring->vsi->netdev, qid);
}
+/**
+ * __i40e_queue_set_napi - Set the napi instance for the queue
+ * @dev: device to which NAPI and queue belong
+ * @queue_index: Index of queue
+ * @type: queue type as RX or TX
+ * @napi: NAPI context
+ * @locked: is the rtnl_lock already held
+ *
+ * Set the napi instance for the queue. Caller indicates the lock status.
+ */
+static void
+__i40e_queue_set_napi(struct net_device *dev, unsigned int queue_index,
+ enum netdev_queue_type type, struct napi_struct *napi,
+ bool locked)
+{
+ if (!locked)
+ rtnl_lock();
+ netif_queue_set_napi(dev, queue_index, type, napi);
+ if (!locked)
+ rtnl_unlock();
+}
+
+/**
+ * i40e_queue_set_napi - Set the napi instance for the queue
+ * @vsi: VSI being configured
+ * @queue_index: Index of queue
+ * @type: queue type as RX or TX
+ * @napi: NAPI context
+ *
+ * Set the napi instance for the queue. The rtnl lock state is derived from the
+ * execution path.
+ */
+void
+i40e_queue_set_napi(struct i40e_vsi *vsi, unsigned int queue_index,
+ enum netdev_queue_type type, struct napi_struct *napi)
+{
+ struct i40e_pf *pf = vsi->back;
+
+ if (!vsi->netdev)
+ return;
+
+ if (current_work() == &pf->service_task ||
+ test_bit(__I40E_PF_RESET_REQUESTED, pf->state) ||
I think we might need something like ICE_PREPARED_FOR_RESET which
detects all kinds of resets(PFR/CORE/GLOBR). __I40E_PF_RESET_REQUESTED
handles PFR only. So, this might assert for RTNL lock on CORER/GLOBR.
+ test_bit(__I40E_DOWN, pf->state) ||
+ test_bit(__I40E_SUSPENDED, pf->state))
+ __i40e_queue_set_napi(vsi->netdev, queue_index, type, napi,
+ false);
+ else
+ __i40e_queue_set_napi(vsi->netdev, queue_index, type, napi,
+ true);
+}
+
/**
* i40e_configure_tx_ring - Configure a transmit ring context and rest
* @ring: The Tx ring to configure
@@ -3558,6 +3610,8 @@ static int i40e_configure_tx_ring(struct i40e_ring *ring)
/* cache tail off for easier writes later */
ring->tail = hw->hw_addr + I40E_QTX_TAIL(pf_q);
+ i40e_queue_set_napi(vsi, ring->queue_index, NETDEV_QUEUE_TYPE_TX,
+ &ring->q_vector->napi);
I am not sure very sure of this, have you tested this for the
reset/rebuild path as well (example: ethtool -L and change queues). Just
wondering if this path is taken for first time VSI init or additionally
for any VSI rebuilds as well.
return 0;
}
@@ -3716,6 +3770,8 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring)
ring->queue_index, pf_q);
}
+ i40e_queue_set_napi(vsi, ring->queue_index, NETDEV_QUEUE_TYPE_RX,
+ &ring->q_vector->napi);
Same as above.
return 0;
}
@@ -4178,6 +4234,8 @@ static int i40e_vsi_request_irq_msix(struct i40e_vsi *vsi, char *basename)
q_vector->affinity_notify.notify = i40e_irq_affinity_notify;
q_vector->affinity_notify.release = i40e_irq_affinity_release;
irq_set_affinity_notifier(irq_num, &q_vector->affinity_notify);
+ netif_napi_set_irq(&q_vector->napi, q_vector->irq_num);
+
/* Spread affinity hints out across online CPUs.
*
* get_cpu_mask returns a static constant mask with
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 64d198ed166b..d380885ff26d 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -821,6 +821,8 @@ void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
void i40e_free_tx_resources(struct i40e_ring *tx_ring)
{
i40e_clean_tx_ring(tx_ring);
+ i40e_queue_set_napi(tx_ring->vsi, tx_ring->queue_index,
+ NETDEV_QUEUE_TYPE_TX, NULL);
kfree(tx_ring->tx_bi);
tx_ring->tx_bi = NULL;
@@ -1526,6 +1528,8 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
void i40e_free_rx_resources(struct i40e_ring *rx_ring)
{
i40e_clean_rx_ring(rx_ring);
+ i40e_queue_set_napi(rx_ring->vsi, rx_ring->queue_index,
+ NETDEV_QUEUE_TYPE_RX, NULL);
if (rx_ring->vsi->type == I40E_VSI_MAIN)
xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
rx_ring->xdp_prog = NULL;