Re: [kvm-unit-tests PATCH v3] runtime: Allow to specify properties for accelerator

[Andrew Jones <andrew.jones@linux.dev>]

On Fri, Jun 16, 2023 at 10:41:29AM +1000, Gavin Shan wrote:
> Hi Nico,
> 
> On 6/15/23 23:39, Nico Boehr wrote:
> > Quoting Gavin Shan (2023-06-15 08:21:48)
> > > There are extra properties for accelerators to enable the specific
> > > features. For example, the dirty ring for KVM accelerator can be
> > > enabled by "-accel kvm,dirty-ring-size=65536". Unfortuntely, the
> > > extra properties for the accelerators aren't supported. It makes
> > > it's impossible to test the combination of KVM and dirty ring
> > > as the following error message indicates.
> > > 
> > >    # cd /home/gavin/sandbox/kvm-unit-tests/tests
> > >    # QEMU=/home/gavin/sandbox/qemu.main/build/qemu-system-aarch64 \
> > >      ACCEL=kvm,dirty-ring-size=65536 ./its-migration
> > >       :
> > >    BUILD_HEAD=2fffb37e
> > >    timeout -k 1s --foreground 90s /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64 \
> > >    -nodefaults -machine virt -accel kvm,dirty-ring-size=65536 -cpu cortex-a57             \
> > >    -device virtio-serial-device -device virtconsole,chardev=ctd -chardev testdev,id=ctd   \
> > >    -device pci-testdev -display none -serial stdio -kernel _NO_FILE_4Uhere_ -smp 160      \
> > >    -machine gic-version=3 -append its-pending-migration # -initrd /tmp/tmp.gfDLa1EtWk
> > >    qemu-system-aarch64: kvm_init_vcpu: kvm_arch_init_vcpu failed (0): Invalid argument
> > > 
> > > Allow to specify extra properties for accelerators. With this, the
> > > "its-migration" can be tested for the combination of KVM and dirty
> > > ring.
> > > 
> > > Signed-off-by: Gavin Shan <gshan@redhat.com>
> > 
> > Maybe get_qemu_accelerator could be renamed now, since it doesn't actually "get"
> > anything, so maybe check_qemu_accelerator?
> > 
> > In any case, I gave it a quick run on s390x with kvm and tcg and nothing seems
> > to break, hence for the changes in s390x:
> > 
> > Tested-by: Nico Boehr <nrb@linux.ibm.com>
> > Acked-by: Nico Boehr <nrb@linux.ibm.com>
> > 
> 
> Thanks for a quick try and comment for this. I guess it's fine to keep the
> function name as get_qemu_accelator() because $ACCEL is split into $ACCEL
> and $ACCEL_PROPS inside it, even it don't print the accelerator name at
> return. However, I'm also fine with check_qemu_accelerator(). Lets see
> what's Drew's comment on this and I can post v4 to have the modified
> function name, or an followup patch to modify the function name.

I suggested naming it set_qemu_accelerator() in the v2 review.

Thanks,
drew