In SW assisted live migration mode, driver will stop the device and
setup a mediated virtio ring to relay the communication between the
virtio driver and the VDPA device.
This data path intervention will allow SW to help on guest dirty page
logging for live migration.
This SW fallback is event driven relay thread, so when the network
throughput is low, this SW fallback will take little CPU resource, but
when the throughput goes up, the relay thread's CPU usage will goes up
accordingly.
User needs to take all the factors including CPU usage, guest perf
degradation, etc. into consideration when selecting the live migration
support mode.
Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
The struct should be ifcvf_net_config other than ifcvf_net_device_config
The variable is used as named opaque variable, struct fields are not
accessed at all, so using wrong struct type has no effect but it should
be fixed.
Fixes: a3f8150eac ("net/ifcvf: add ifcvf vDPA driver")
Cc: stable@dpdk.org
Signed-off-by: Xiaolong Ye <xiaolong.ye@intel.com>
Acked-by: Xiao Wang <xiao.w.wang@intel.com>
NICs uses different delays up to a second during their
configuration. It makes no sense to busy-wait so long wasting
CPU cycles and preventing any other threads to execute on the
same CPU core. These busy polling are the rudiments that came
from the kernel drivers where you can not sleep in interrupt
context, but as we're in userspace, we're able and should
sleep to allow other threads to run.
Delays never called on rx/tx path, so this should not affect
performance.
Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
IFCVF can help to log dirty page in live migration stage,
each queue's index can be read and configured to support
VHOST_USER_GET_VRING_BASE and VHOST_USER_SET_VRING_BASE.
Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Reviewed-by: Xiaolong Ye <xiaolong.ye@intel.com>
Tested-by: Xiaolong Ye <xiaolong.ye@intel.com>
The IFCVF vDPA (vhost data path acceleration) driver provides support for
the Intel FPGA 100G VF (IFCVF). IFCVF's datapath is virtio ring compatible,
it works as a HW vhost backend which can send/receive packets to/from
virtio directly by DMA.
Different VF devices serve different virtio frontends which are in
different VMs, so each VF needs to have its own DMA address translation
service. During the driver probe a new container is created, with this
container vDPA driver can program DMA remapping table with the VM's memory
region information.
Key vDPA driver ops implemented:
- ifcvf_dev_config:
Enable VF data path with virtio information provided by vhost lib,
including IOMMU programming to enable VF DMA to VM's memory, VFIO
interrupt setup to route HW interrupt to virtio driver, create notify
relay thread to translate virtio driver's kick to a MMIO write onto HW,
HW queues configuration.
- ifcvf_dev_close:
Revoke all the setup in ifcvf_dev_config.
Live migration feature is supported by IFCVF and this driver enables
it. For the dirty page logging, VF helps to log for packet buffer write,
driver helps to make the used ring as dirty when device stops.
Because vDPA driver needs to set up MSI-X vector to interrupt the
guest, only vfio-pci is supported currently.
Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Signed-off-by: Rosen Xu <rosen.xu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
