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

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

On Tue, Jun 20, 2023 at 02:13:22PM +1000, Gavin Shan wrote:
> Hi Drew,
> 
> On 6/19/23 18:45, Andrew Jones wrote:
> > On Thu, Jun 15, 2023 at 04:21:48PM +1000, Gavin Shan wrote:
> > > 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>
> > > ---
> > > v3: Split $ACCEL to $ACCEL and $ACCEL_PROPS in get_qemu_accelerator()
> > >      and don't print them as output, suggested by Drew.
> > > ---
> > >   arm/run               | 12 ++++--------
> > >   powerpc/run           |  5 ++---
> > >   s390x/run             |  5 ++---
> > >   scripts/arch-run.bash | 21 +++++++++++++--------
> > >   x86/run               |  5 ++---
> > >   5 files changed, 23 insertions(+), 25 deletions(-)
> > > 
> > > diff --git a/arm/run b/arm/run
> > > index c6f25b8..d9ebe59 100755
> > > --- a/arm/run
> > > +++ b/arm/run
> > > @@ -10,10 +10,8 @@ if [ -z "$KUT_STANDALONE" ]; then
> > >   fi
> > >   processor="$PROCESSOR"
> > > -accel=$(get_qemu_accelerator) ||
> > > -	exit $?
> > > -
> > > -if [ "$accel" = "kvm" ]; then
> > > +get_qemu_accelerator || exit $?
> > > +if [ "$ACCEL" = "kvm" ]; then
> > >   	QEMU_ARCH=$HOST
> > >   fi
> > > @@ -23,11 +21,9 @@ qemu=$(search_qemu_binary) ||
> > >   if [ "$QEMU" ] && [ -z "$ACCEL" ] &&
> > >      [ "$HOST" = "aarch64" ] && [ "$ARCH" = "arm" ] &&
> > >      [ "$(basename $QEMU)" = "qemu-system-arm" ]; then
> > > -	accel=tcg
> > > +	ACCEL="tcg"
> > >   fi
> > 
> > As I pointed out in the v2 review we can't just s/accel/ACCEL/ without
> > other changes. Now ACCEL will also be set when the above condition
> > is checked, making it useless. Please ensure the test case that commit
> > c7d6c7f00e7c ("arm/run: Use TCG with qemu-system-arm on arm64 systems")
> > fixed still works with your patch.
> > 
> 
> Sorry that I missed your comments for v2. In order to make the test case
> in c7d6c7f00e7c working, we just need to call set_qemu_accelerator() after
> the chunk of code, like below. When $ACCEL is set to "tcg" by the conditional
> code, it won't be changed in the following set_qemu_accelerator().
> 
> Could you Please confirm if it looks good to you so that I can integrate
> the changes to v4 and post it.
> 
> arm/run
> --------
> 
> processor="$PROCESSOR"
> 
> if [ "$QEMU" ] && [ -z "$ACCEL" ] &&
>    [ "$HOST" = "aarch64" ] && [ "$ARCH" = "arm" ] &&
>    [ "$(basename $QEMU)" = "qemu-system-arm" ]; then
>         ACCEL="tcg"
> fi
> 
> set_qemu_accelerator || exit $?
> if [ "$ACCEL" = "kvm" ]; then
>         QEMU_ARCH=$HOST
> fi
>

Looks fine, but please give it a test run.

Thanks,
drew