The main idea behind this commit is to remove all the complexity
associated with TX/RX handling for virtio-net. By using writev() and
readv() syscalls, we could get rid of intermediate buffers for both
queues.
The complexity regarding the TAP registration has been simplified as
well. The RX queue is only processed when some data are ready to be
read from TAP. The event related to the RX queue getting more
descriptors only serves the purpose to register the TAP file if it's not
already.
With all these simplifications, the code is more readable but more
performant as well. We can see an improvement of 10% for a single
queue device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
EpollHelper allows the removal of much duplicated loop handling code and
instead the device specific even handling is delegated via an
implementation of EpollHelperHandler.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Move NetQueuePair and the related NetCounters into the net_util crate.
This means that the vhost_user_net crate now no longer depends on
virtio-devices and so does not depend on the pci, qcow or other similar
crates. This significantly simplifies the build chain for this backend.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
By moving the code for opening the two RX and TX queues into a shared
location we are starting to remove the requirement for the
vhost-user-net backend to depend on the virtio-devices crate which in of
itself depends on many other crates that are not necessary for the
backend to function.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
