On 10/29/2024 10:12 PM, Joe Damato wrote:
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@xxxxxxxxxx>
Reviewed-by: Vitaly Lifshits <vitaly.lifshits@xxxxxxxxx>
---
v6:
- Rename __igc_do_resume to __igc_resume and rename the boolean
argument "need_rtnl" to "rpm" as seen in igb, as per Vitaly's
feedback to make the code look more like commit ac8c58f5b535 ("igb:
fix deadlock caused by taking RTNL in RPM resume path").
v5:
- Rename igc_resume to __igc_do_resume and pass in a boolean
"need_rtnl" to signal whether or not rtnl should be held before
caling __igc_open. Call this new function from igc_runtime_resume
and igc_resume passing in false (for igc_runtime_resume) and true
(igc_resume), respectively. This is done to avoid reintroducing a
bug fixed in commit: 6f31d6b: "igc: Refactor runtime power
management flow" where rtnl is held in runtime_resume causing a
deadlock.
v4:
- Add rtnl_lock/rtnl_unlock in two paths: igc_resume and
igc_io_error_detected. The code added to the latter is inspired by
a similar implementation in ixgbe's ixgbe_io_error_detected.
v3:
- Replace igc_unset_queue_napi with igc_set_queue_napi(adapater, i,
NULL), as suggested by Vinicius Costa Gomes
- Simplify implemention of igc_set_queue_napi as suggested by Kurt
Kanzenbach, with a tweak to use ring->queue_index
v2:
- Update commit message to include tests for IGC_FLAG_QUEUE_PAIRS
disabled
- Refactored code to move napi queue mapping and unmapping to helper
functions igc_set_queue_napi and igc_unset_queue_napi
- Adjust the code to handle IGC_FLAG_QUEUE_PAIRS disabled
- Call helpers to map/unmap queues to NAPIs in igc_up, __igc_open,
igc_xdp_enable_pool, and igc_xdp_disable_pool
drivers/net/ethernet/intel/igc/igc.h | 2 +
drivers/net/ethernet/intel/igc/igc_main.c | 56 +++++++++++++++++++----
drivers/net/ethernet/intel/igc/igc_xdp.c | 2 +
3 files changed, 51 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index eac0f966e0e4..b8111ad9a9a8 100644
--- 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 7964bbedb16c..9a5ece12e9d4 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -4948,6 +4948,22 @@ 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
@@ -4955,6 +4971,7 @@ 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 */
@@ -4962,8 +4979,11 @@ 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);
@@ -5192,6 +5212,7 @@ 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);
}
}
@@ -6021,6 +6042,7 @@ 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;
@@ -6056,8 +6078,11 @@ 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);
@@ -7342,7 +7367,7 @@ 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);
@@ -7385,7 +7410,11 @@ 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);
}
@@ -7393,9 +7422,14 @@ 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)
@@ -7440,14 +7474,18 @@ 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;
@@ -7458,7 +7496,7 @@ 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)
{
@@ -7497,7 +7535,7 @@ 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 e27af72aada8..4da633430b80 100644
--- a/drivers/net/ethernet/intel/igc/igc_xdp.c
+++ b/drivers/net/ethernet/intel/igc/igc_xdp.c
@@ -84,6 +84,7 @@ 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);
@@ -133,6 +134,7 @@ 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);
