[PATCH] igb: do not re-init SR-IOV during probe

[PATCH] igb: do not re-init SR-IOV during probe

[Stefan Assmann]

During driver probing the following code path is triggered.
igb_probe
->igb_sw_init
  ->igb_probe_vfs
    ->igb_pci_enable_sriov
      ->igb_sriov_reinit

Doing the SR-IOV re-init is not necessary during probing since we're
starting from scratch. Here we can call igb_enable_sriov() right away.

Running igb_sriov_reinit() during igb_probe() also seems to cause
occasional packet loss on some onboard 82576 NICs. Reproduced on
Dell and HP servers with onboard 82576 NICs.
Example:
Intel Corporation 82576 Gigabit Network Connection [8086:10c9] (rev 01)
Subsystem: Dell Device [1028:0481]

Signed-off-by: Stefan Assmann <sassmann@kpanic.de>
---
 drivers/net/ethernet/intel/igb/igb_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index f287186..7f41237 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -2847,7 +2847,7 @@ static void igb_probe_vfs(struct igb_adapter *adapter)
 		return;
 
 	pci_sriov_set_totalvfs(pdev, 7);
-	igb_pci_enable_sriov(pdev, max_vfs);
+	igb_enable_sriov(pdev, max_vfs);
 
 #endif /* CONFIG_PCI_IOV */
 }
-- 
2.4.3

RE: [PATCH] igb: do not re-init SR-IOV during probe

[Brown, Aaron F]

> From: netdev-owner@vger.kernel.org [mailto:netdev-owner@vger.kernel.org]
> On Behalf Of Stefan Assmann
> Sent: Friday, July 10, 2015 6:01 AM
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; Kirsher, Jeffrey T; sassmann@kpanic.de
> Subject: [PATCH] igb: do not re-init SR-IOV during probe
> 
> During driver probing the following code path is triggered.
> igb_probe
> ->igb_sw_init
>   ->igb_probe_vfs
>     ->igb_pci_enable_sriov
>       ->igb_sriov_reinit
> 
> Doing the SR-IOV re-init is not necessary during probing since we're
> starting from scratch. Here we can call igb_enable_sriov() right away.
> 
> Running igb_sriov_reinit() during igb_probe() also seems to cause
> occasional packet loss on some onboard 82576 NICs. Reproduced on
> Dell and HP servers with onboard 82576 NICs.
> Example:
> Intel Corporation 82576 Gigabit Network Connection [8086:10c9] (rev 01)
> Subsystem: Dell Device [1028:0481]
> 
> Signed-off-by: Stefan Assmann <sassmann@kpanic.de>
> ---
>  drivers/net/ethernet/intel/igb/igb_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 

Tested-by: Aaron Brown <aaron.f.brown@intel.com>