> -----Original Message----- > From: Intel-wired-lan <[email protected]> On Behalf Of > Robert Malz > Sent: Wednesday, October 22, 2025 6:12 PM > To: [email protected]; [email protected] > Cc: Jamie Bainbridge <[email protected]>; Michal Swiatkowski > <[email protected]>; Dennis Chen <[email protected]>; > Robert Malz <[email protected]>; Kitszel, Przemyslaw > <[email protected]>; Czapnik, Lukasz > <[email protected]>; Loktionov, Aleksandr > <[email protected]>; Andrew Lunn <[email protected]>; > Eric Dumazet <[email protected]>; Nguyen, Anthony L > <[email protected]>; Simon Horman <[email protected]>; Keller, > Jacob E <[email protected]>; Jakub Kicinski <[email protected]>; Paolo > Abeni <[email protected]>; David S . Miller <[email protected]> > Subject: [Intel-wired-lan] [PATCH v2] i40e: avoid redundant VF link state > updates > > From: Jay Vosburgh <[email protected]> > > Multiple sources can request VF link state changes with identical parameters. > For example, OpenStack Neutron may request to set the VF link state to > IFLA_VF_LINK_STATE_AUTO during every initialization or user can > issue: `ip link set <ifname> vf 0 state auto` multiple times. Currently, the > i40e > driver processes each of these requests, even if the requested state is the > same as the current one. This leads to unnecessary VF resets and can cause > performance degradation or instability in the VF driver, particularly in > environment using Data Plane Development Kit (DPDK). > > With this patch i40e will skip VF link state change requests when the desired > link state matches the current configuration. This prevents unnecessary VF > resets and reduces PF-VF communication overhead. > > To reproduce the problem run following command multiple times on the same > interface: 'ip link set <ifname> vf 0 state auto' > Every time command is executed, PF driver will trigger VF reset. > > Co-developed-by: Robert Malz <[email protected]> > Signed-off-by: Robert Malz <[email protected]> > Signed-off-by: Jay Vosburgh <[email protected]> > > --- > V1 -> V2: updated commit message, added information how to reproduce > > drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) >
Tested-by: Rafal Romanowski <[email protected]>
