igc: Link queues to NAPI instances

Link queues to NAPI instances via netdev-genl API so that users can
query this information with netlink. Handle a few cases in the driver:
  1. Link/unlink the NAPIs when XDP is enabled/disabled
  2. Handle IGC_FLAG_QUEUE_PAIRS enabled and disabled

Example output when IGC_FLAG_QUEUE_PAIRS is enabled:

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                         --dump queue-get --json='{"ifindex": 2}'

[{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'rx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 8194, 'type': 'rx'},
 {'id': 2, 'ifindex': 2, 'napi-id': 8195, 'type': 'rx'},
 {'id': 3, 'ifindex': 2, 'napi-id': 8196, 'type': 'rx'},
 {'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'tx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 8194, 'type': 'tx'},
 {'id': 2, 'ifindex': 2, 'napi-id': 8195, 'type': 'tx'},
 {'id': 3, 'ifindex': 2, 'napi-id': 8196, 'type': 'tx'}]

Since IGC_FLAG_QUEUE_PAIRS is enabled, you'll note that the same NAPI ID
is present for both rx and tx queues at the same index, for example
index 0:

{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'rx'},
{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'tx'},

To test IGC_FLAG_QUEUE_PAIRS disabled, a test system was booted using
the grub command line option "maxcpus=2" to force
igc_set_interrupt_capability to disable IGC_FLAG_QUEUE_PAIRS.

Example output when IGC_FLAG_QUEUE_PAIRS is disabled:

$ lscpu | grep "On-line CPU"
On-line CPU(s) list:      0,2

$ ethtool -l enp86s0  | tail -5
Current hardware settings:
RX:		n/a
TX:		n/a
Other:		1
Combined:	2

$ cat /proc/interrupts  | grep enp
 144: [...] enp86s0
 145: [...] enp86s0-rx-0
 146: [...] enp86s0-rx-1
 147: [...] enp86s0-tx-0
 148: [...] enp86s0-tx-1

1 "other" IRQ, and 2 IRQs for each of RX and Tx, so we expect netlink to
report 4 IRQs with unique NAPI IDs:

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                         --dump napi-get --json='{"ifindex": 2}'
[{'id': 8196, 'ifindex': 2, 'irq': 148},
 {'id': 8195, 'ifindex': 2, 'irq': 147},
 {'id': 8194, 'ifindex': 2, 'irq': 146},
 {'id': 8193, 'ifindex': 2, 'irq': 145}]

Now we examine which queues these NAPIs are associated with, expecting
that since IGC_FLAG_QUEUE_PAIRS is disabled each RX and TX queue will
have its own NAPI instance:

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                         --dump queue-get --json='{"ifindex": 2}'
[{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'rx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 8194, 'type': 'rx'},
 {'id': 0, 'ifindex': 2, 'napi-id': 8195, 'type': 'tx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 8196, 'type': 'tx'}]

Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Vitaly Lifshits <vitaly.lifshits@intel.com>
Tested-by: Avigail Dahan <avigailx.dahan@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://patch.msgid.link/20250106221929.956999-15-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index eac0f966e0e4c5237475c7321f50cae65a395606..b8111ad9a9a83dbe1257d8011e046cbd263022c3 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc.h
+++ b/drivers/net/ethernet/intel/igc/igc.h
@@ -337,6 +337,8 @@ struct igc_adapter {
        struct igc_led_classdev *leds;
 };
 
+void igc_set_queue_napi(struct igc_adapter *adapter, int q_idx,
+                       struct napi_struct *napi);
 void igc_up(struct igc_adapter *adapter);
 void igc_down(struct igc_adapter *adapter);
 int igc_open(struct net_device *netdev);

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index d9542015e871562aaeb1f2ba39baf71846d7ded8..56a35d58e7a6290606931f4ab4cb814cbe30f146 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -4942,6 +4942,22 @@ static int igc_sw_init(struct igc_adapter *adapter)
        return 0;
 }
 
+void igc_set_queue_napi(struct igc_adapter *adapter, int vector,
+                       struct napi_struct *napi)
+{
+       struct igc_q_vector *q_vector = adapter->q_vector[vector];
+
+       if (q_vector->rx.ring)
+               netif_queue_set_napi(adapter->netdev,
+                                    q_vector->rx.ring->queue_index,
+                                    NETDEV_QUEUE_TYPE_RX, napi);
+
+       if (q_vector->tx.ring)
+               netif_queue_set_napi(adapter->netdev,
+                                    q_vector->tx.ring->queue_index,
+                                    NETDEV_QUEUE_TYPE_TX, napi);
+}
+
 /**
  * igc_up - Open the interface and prepare it to handle traffic
  * @adapter: board private structure
@@ -4949,6 +4965,7 @@ static int igc_sw_init(struct igc_adapter *adapter)
 void igc_up(struct igc_adapter *adapter)
 {
        struct igc_hw *hw = &adapter->hw;
+       struct napi_struct *napi;
        int i = 0;
 
        /* hardware has been reset, we need to reload some things */
@@ -4956,8 +4973,11 @@ void igc_up(struct igc_adapter *adapter)
 
        clear_bit(__IGC_DOWN, &adapter->state);
 
-       for (i = 0; i < adapter->num_q_vectors; i++)
-               napi_enable(&adapter->q_vector[i]->napi);
+       for (i = 0; i < adapter->num_q_vectors; i++) {
+               napi = &adapter->q_vector[i]->napi;
+               napi_enable(napi);
+               igc_set_queue_napi(adapter, i, napi);
+       }
 
        if (adapter->msix_entries)
                igc_configure_msix(adapter);
@@ -5186,6 +5206,7 @@ void igc_down(struct igc_adapter *adapter)
        for (i = 0; i < adapter->num_q_vectors; i++) {
                if (adapter->q_vector[i]) {
                        napi_synchronize(&adapter->q_vector[i]->napi);
+                       igc_set_queue_napi(adapter, i, NULL);
                        napi_disable(&adapter->q_vector[i]->napi);
                }
        }
@@ -6015,6 +6036,7 @@ static int __igc_open(struct net_device *netdev, bool resuming)
        struct igc_adapter *adapter = netdev_priv(netdev);
        struct pci_dev *pdev = adapter->pdev;
        struct igc_hw *hw = &adapter->hw;
+       struct napi_struct *napi;
        int err = 0;
        int i = 0;
 
@@ -6050,8 +6072,11 @@ static int __igc_open(struct net_device *netdev, bool resuming)
 
        clear_bit(__IGC_DOWN, &adapter->state);
 
-       for (i = 0; i < adapter->num_q_vectors; i++)
-               napi_enable(&adapter->q_vector[i]->napi);
+       for (i = 0; i < adapter->num_q_vectors; i++) {
+               napi = &adapter->q_vector[i]->napi;
+               napi_enable(napi);
+               igc_set_queue_napi(adapter, i, napi);
+       }
 
        /* Clear any pending interrupts. */
        rd32(IGC_ICR);
@@ -7296,7 +7321,7 @@ static void igc_deliver_wake_packet(struct net_device *netdev)
        netif_rx(skb);
 }
 
-static int igc_resume(struct device *dev)
+static int __igc_resume(struct device *dev, bool rpm)
 {
        struct pci_dev *pdev = to_pci_dev(dev);
        struct net_device *netdev = pci_get_drvdata(pdev);
@@ -7339,7 +7364,11 @@ static int igc_resume(struct device *dev)
        wr32(IGC_WUS, ~0);
 
        if (netif_running(netdev)) {
+               if (!rpm)
+                       rtnl_lock();
                err = __igc_open(netdev, true);
+               if (!rpm)
+                       rtnl_unlock();
                if (!err)
                        netif_device_attach(netdev);
        }
@@ -7347,9 +7376,14 @@ static int igc_resume(struct device *dev)
        return err;
 }
 
+static int igc_resume(struct device *dev)
+{
+       return __igc_resume(dev, false);
+}
+
 static int igc_runtime_resume(struct device *dev)
 {
-       return igc_resume(dev);
+       return __igc_resume(dev, true);
 }
 
 static int igc_suspend(struct device *dev)
@@ -7394,14 +7428,18 @@ static pci_ers_result_t igc_io_error_detected(struct pci_dev *pdev,
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct igc_adapter *adapter = netdev_priv(netdev);
 
+       rtnl_lock();
        netif_device_detach(netdev);
 
-       if (state == pci_channel_io_perm_failure)
+       if (state == pci_channel_io_perm_failure) {
+               rtnl_unlock();
                return PCI_ERS_RESULT_DISCONNECT;
+       }
 
        if (netif_running(netdev))
                igc_down(adapter);
        pci_disable_device(pdev);
+       rtnl_unlock();
 
        /* Request a slot reset. */
        return PCI_ERS_RESULT_NEED_RESET;
@@ -7412,7 +7450,7 @@ static pci_ers_result_t igc_io_error_detected(struct pci_dev *pdev,
  *  @pdev: Pointer to PCI device
  *
  *  Restart the card from scratch, as if from a cold-boot. Implementation
- *  resembles the first-half of the igc_resume routine.
+ *  resembles the first-half of the __igc_resume routine.
  **/
 static pci_ers_result_t igc_io_slot_reset(struct pci_dev *pdev)
 {
@@ -7451,7 +7489,7 @@ static pci_ers_result_t igc_io_slot_reset(struct pci_dev *pdev)
  *
  *  This callback is called when the error recovery driver tells us that
  *  its OK to resume normal operation. Implementation resembles the
- *  second-half of the igc_resume routine.
+ *  second-half of the __igc_resume routine.
  */
 static void igc_io_resume(struct pci_dev *pdev)
 {

diff --git a/drivers/net/ethernet/intel/igc/igc_xdp.c b/drivers/net/ethernet/intel/igc/igc_xdp.c
index 869815f48ac1d2d6fb185756348d75d8054497cf..13bbd3346e01f394935b25aef4e70e3d323d4197 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc_xdp.c
+++ b/drivers/net/ethernet/intel/igc/igc_xdp.c
@@ -86,6 +86,7 @@ static int igc_xdp_enable_pool(struct igc_adapter *adapter,
                napi_disable(napi);
        }
 
+       igc_set_queue_napi(adapter, queue_id, NULL);
        set_bit(IGC_RING_FLAG_AF_XDP_ZC, &rx_ring->flags);
        set_bit(IGC_RING_FLAG_AF_XDP_ZC, &tx_ring->flags);
 
@@ -135,6 +136,7 @@ static int igc_xdp_disable_pool(struct igc_adapter *adapter, u16 queue_id)
        xsk_pool_dma_unmap(pool, IGC_RX_DMA_ATTR);
        clear_bit(IGC_RING_FLAG_AF_XDP_ZC, &rx_ring->flags);
        clear_bit(IGC_RING_FLAG_AF_XDP_ZC, &tx_ring->flags);
+       igc_set_queue_napi(adapter, queue_id, napi);
 
        if (needs_reset) {
                napi_enable(napi);