On Fri, Jun 14, 2024 at 2:48 AM David Marchand <[email protected]> wrote: > > Querying link status may get delayed for an undeterministic (long) time > with mlx5 ports. This is a consequence of the mlx5 driver calling ethtool > kernel API and getting stuck on the kernel RTNL lock while some other > operation is in progress under this lock. > > One impact for long link status query is that it is called under the bond > lock taken in write mode periodically in bond_run(). > In parallel, datapath threads may block requesting to read bonding related > info (like for example in bond_check_admissibility()). > > The LSC interrupt mode is available with many DPDK drivers and is used by > default with testpmd. > > It seems safe enough to switch on this feature by default in OVS. > We keep the per interface option to disable this feature in case of an > unforeseen bug. > > Signed-off-by: David Marchand <[email protected]> > --- > Changes since v1: > - (early) fail when interrupt lsc is requested by user but not supported > by the driver, > - otherwise, log a debug message if user did not request interrupt mode, > > --- > Documentation/topics/dpdk/phy.rst | 4 ++-- > NEWS | 3 +++ > lib/netdev-dpdk.c | 13 ++++++++++++- > vswitchd/vswitch.xml | 8 ++++---- > 4 files changed, 21 insertions(+), 7 deletions(-) > > diff --git a/Documentation/topics/dpdk/phy.rst > b/Documentation/topics/dpdk/phy.rst > index efd168cba8..eefc25613d 100644 > --- a/Documentation/topics/dpdk/phy.rst > +++ b/Documentation/topics/dpdk/phy.rst > @@ -546,8 +546,8 @@ the firmware every time to fulfil this request. > > Note that not all PMD drivers support LSC interrupts. > > -The default configuration is polling mode. To set interrupt mode, option > -``dpdk-lsc-interrupt`` has to be set to ``true``. > +The default configuration is interrupt mode. To set polling mode, option > +``dpdk-lsc-interrupt`` has to be set to ``false``. > > Command to set interrupt mode for a specific interface:: > $ ovs-vsctl set interface <iface_name> options:dpdk-lsc-interrupt=true > diff --git a/NEWS b/NEWS > index 5ae0108d55..1e19beb793 100644 > --- a/NEWS > +++ b/NEWS > @@ -9,6 +9,9 @@ Post-v3.3.0 > https://github.com/openvswitch/ovs.git > - DPDK: > * OVS validated with DPDK 23.11.1. > + * Link status changes are now handled via interrupt mode if the DPDK > + driver supports it. It is possible to revert to polling mode by > setting > + per interface 'dpdk-lsc-interrupt' other_config to 'false'.
As Robin points out, other_config should be changed to options.But the rest looks good. Acked-by: Mike Pattrick <[email protected]> > > > v3.3.0 - 16 Feb 2024 > diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c > index 0fa37d5145..a260bc8485 100644 > --- a/lib/netdev-dpdk.c > +++ b/lib/netdev-dpdk.c > @@ -2397,7 +2397,18 @@ netdev_dpdk_set_config(struct netdev *netdev, const > struct smap *args, > } > } > > - lsc_interrupt_mode = smap_get_bool(args, "dpdk-lsc-interrupt", false); > + lsc_interrupt_mode = smap_get_bool(args, "dpdk-lsc-interrupt", true); > + if (lsc_interrupt_mode && !(*info.dev_flags & RTE_ETH_DEV_INTR_LSC)) { > + if (smap_get(args, "dpdk-lsc-interrupt")) { > + VLOG_ERR("interface '%s': link status interrupt is not > supported.", > + netdev_get_name(netdev)); > + err = EINVAL; > + goto out; > + } > + VLOG_DBG("interface '%s': not enabling link status interrupt.", > + netdev_get_name(netdev)); > + lsc_interrupt_mode = false; > + } > if (dev->requested_lsc_interrupt_mode != lsc_interrupt_mode) { > dev->requested_lsc_interrupt_mode = lsc_interrupt_mode; > netdev_request_reconfigure(netdev); > diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml > index 8a1b607d71..e3afb78a4e 100644 > --- a/vswitchd/vswitch.xml > +++ b/vswitchd/vswitch.xml > @@ -4647,12 +4647,12 @@ ovs-vsctl add-port br0 p0 -- set Interface p0 > type=patch options:peer=p1 \ > <column name="options" key="dpdk-lsc-interrupt" > type='{"type": "boolean"}'> > <p> > - Set this value to <code>true</code> to configure interrupt mode for > - Link State Change (LSC) detection instead of poll mode for the DPDK > - interface. > + Set this value to <code>false</code> to configure poll mode for > + Link State Change (LSC) detection instead of interrupt mode for the > + DPDK interface. > </p> > <p> > - If this value is not set, poll mode is configured. > + If this value is not set, interrupt mode is configured. > </p> > <p> > This parameter has an effect only on netdev dpdk interfaces. > -- > 2.44.0 > _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
