diff mbox series

[net-next,3/4] igc: Refactor runtime power management flow

Message ID 20240329175632.211340-4-anthony.l.nguyen@intel.com (mailing list archive)
State Accepted
Commit 6f31d6b643a32cc126cf86093fca1ea575948bf0
Delegated to: Netdev Maintainers
Headers show
Series Intel Wired LAN Driver Updates 2024-03-29 (net: intel) | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 943 this patch: 943
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 4 of 4 maintainers
netdev/build_clang success Errors and warnings before: 954 this patch: 954
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 954 this patch: 954
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 57 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-03-31--03-00 (tests: 953)

Commit Message

Tony Nguyen March 29, 2024, 5:56 p.m. UTC 
From: Sasha Neftin <sasha.neftin@intel.com>

Following the corresponding discussion [1] and [2] refactor the 'igc_open'
method and avoid taking the rtnl_lock() during the 'igc_resume' method.
The rtnl_lock is held by the upper layer and could lead to the deadlock
during resuming from a runtime power management flow. Notify the stack of
the actual queue counts 'netif_set_real_num_*_queues' outside the
'_igc_open' wrapper. This notification doesn't have to be called on each
resume.

Test:
1. Disconnect the ethernet cable
2. Enable the runtime power management via file system:
echo auto > /sys/devices/pci0000\.../power/control
3. Check the device state (lspci -s <device> -vvv | grep -i Status)

Link: https://lore.kernel.org/netdev/20231206113934.8d7819857574.I2deb5804
ef1739a2af307283d320ef7d82456494@changeid/#r [1]
Link: https://lore.kernel.org/netdev/20211125074949.5f897431@kicinski-fedo
ra-pc1c0hjn.dhcp.thefacebook.com/t/ [2]
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/igc/igc_main.c | 32 +++++++++++------------
 1 file changed, 15 insertions(+), 17 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 998d8c345a78..d9bd001af7ba 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -5929,15 +5929,6 @@  static int __igc_open(struct net_device *netdev, bool resuming)
 	if (err)
 		goto err_req_irq;
 
-	/* Notify the stack of the actual queue counts. */
-	err = netif_set_real_num_tx_queues(netdev, adapter->num_tx_queues);
-	if (err)
-		goto err_set_queues;
-
-	err = netif_set_real_num_rx_queues(netdev, adapter->num_rx_queues);
-	if (err)
-		goto err_set_queues;
-
 	clear_bit(__IGC_DOWN, &adapter->state);
 
 	for (i = 0; i < adapter->num_q_vectors; i++)
@@ -5958,8 +5949,6 @@  static int __igc_open(struct net_device *netdev, bool resuming)
 
 	return IGC_SUCCESS;
 
-err_set_queues:
-	igc_free_irq(adapter);
 err_req_irq:
 	igc_release_hw_control(adapter);
 	igc_power_down_phy_copper_base(&adapter->hw);
@@ -5976,6 +5965,17 @@  static int __igc_open(struct net_device *netdev, bool resuming)
 
 int igc_open(struct net_device *netdev)
 {
+	struct igc_adapter *adapter = netdev_priv(netdev);
+	int err;
+
+	/* Notify the stack of the actual queue counts. */
+	err = netif_set_real_num_queues(netdev, adapter->num_tx_queues,
+					adapter->num_rx_queues);
+	if (err) {
+		netdev_err(netdev, "error setting real queue count\n");
+		return err;
+	}
+
 	return __igc_open(netdev, false);
 }
 
@@ -7181,13 +7181,11 @@  static int igc_resume(struct device *dev)
 
 	wr32(IGC_WUS, ~0);
 
-	rtnl_lock();
-	if (!err && netif_running(netdev))
+	if (netif_running(netdev)) {
 		err = __igc_open(netdev, true);
-
-	if (!err)
-		netif_device_attach(netdev);
-	rtnl_unlock();
+		if (!err)
+			netif_device_attach(netdev);
+	}
 
 	return err;
 }