Re: [kvm-unit-tests RFC PATCH 3/5] run_tests.sh: Add kvmtool support

Alexandru Elisei
2021-09-08T14:31:59Z

Hi Drew,

Thanks for having a look so quickly!

On 9/7/21 11:17 AM, Andrew Jones wrote:
> On Fri, Jul 02, 2021 at 05:31:20PM +0100, Alexandru Elisei wrote:
>> Modify run_tests.sh to use kvmtool instead of qemu to run tests when
>> kvm-unit-tests has been configured with --target=kvmtool.
>>
>> Example invocation:
>>
>> $ ./configure --target=kvmtool
>> $ make clean && make
>> $ ./run_scripts.sh
>>
>> A custom location for the kvmtool binary can be set using the environment
>> variable KVMTOOL:
>>
>> $ KVMTOOL=/path/to/kvmtool/binary ./run_scripts.sh
>>
>> Standalone test support is absent, but will be added in subsequent patches.
>>
>> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
>> ---
>> scripts/arch-run.bash | 48 ++++++++++++++++--
>> scripts/runtime.bash | 94 ++++++++++++++++++++++++++++------
>> scripts/mkstandalone.sh | 5 ++
>> arm/run | 110 ++++++++++++++++++++++++----------------
>> run_tests.sh | 11 +++-
>> 5 files changed, 204 insertions(+), 64 deletions(-)
>>
>> diff --git a/scripts/arch-run.bash b/scripts/arch-run.bash
>> index 8ceed53ed7f8..b916b0e79aca 100644
>> --- a/scripts/arch-run.bash
>> +++ b/scripts/arch-run.bash
>> @@ -69,16 +69,39 @@ run_qemu ()
>> return $ret
>> }
>>
>> +run_kvmtool()
>> +{
>> + local stdout errors ret sig
>> +
>> + # kvmtool doesn't allow an initrd argument with --firmware, but configure
>> + # sets CONFIG_ERRATA_FORCE in lib/config.h for the kvmtool target.
>> +
>> + # stdout to {stdout}, stderr to $errors and stderr
>> + exec {stdout}>&1
>> + errors=$("${@}" </dev/null 2> >(tee /dev/stderr) > /dev/fd/$stdout)
>> + ret=$?
>> + exec {stdout}>&-
>> +
>> + # ret=0 success, everything else is failure.
>> + return $ret
>> +}
>> +
>> run_test_status ()
>> {
>> - local stdout ret
>> + local stdout ret exit_status
>>
>> exec {stdout}>&1
>> - lines=$(run_qemu "$@" > >(tee /dev/fd/$stdout))
>> + if [ "$TARGET" = "kvmtool" ]; then
>> + lines=$(run_kvmtool "$@" > >(tee /dev/fd/$stdout))
>> + exit_status=0
>> + else
>> + lines=$(run_qemu "$@" > >(tee /dev/fd/$stdout))
>> + exit_status=1
>> + fi
> Now that we're adding a second VMM, let's assume that we may want to add
> more. (Actually, I have low priority aspirations to try and also use a
> Rust VMM, for example). To prepare for another VMM, everywhere we add a
> kvmtool case like this, we should use a case statement instead, e.g.
>
> case "$TARGET" in
> qemu)
> lines=$(run_qemu "$@" > >(tee /dev/fd/$stdout))
> exit_status=1
> ;;
> kvmtool)
> lines=$(run_kvmtool "$@" > >(tee /dev/fd/$stdout))
> exit_status=0
> *) echo "$BASH_SOURCE $LINENO"; exit 2;;
> esac
>
> This means we also need to modify configure to unconditionally do
>
> echo "TARGET=$target" >> config.mak
>
> Right now it only does that for arm/arm64.

Yep, using a case statement makes more sense. I'll update everywhere you've
pointed out.

I'll modify configure to set the TARGET variable unconditionally in config.mak.

>
>> ret=$?
>> exec {stdout}>&-
>>
>> - if [ $ret -eq 1 ]; then
>> + if [ $ret -eq $exit_status ]; then
>> testret=$(grep '^EXIT: ' <<<"$lines" | sed 's/.*STATUS=\([0-9][0-9]*\).*/\1/')
>> if [ "$testret" ]; then
>> if [ $testret -eq 1 ]; then
>> @@ -193,6 +216,25 @@ search_qemu_binary ()
>> export PATH=$save_path
>> }
>>
>> +search_kvmtool_binary ()
>> +{
>> + local lkvm kvmtool
>> +
>> + for lkvm in ${KVMTOOL:-lkvm vm lkvm-static}; do
>> + if $lkvm --help 2>/dev/null | grep -q 'The most commonly used'; then
>> + kvmtool="$lkvm"
>> + break
>> + fi
>> + done
>> +
>> + if [ -z "$kvmtool" ]; then
>> + echo "A kvmtool binary was not found." >&2
>> + echo "You can set a custom location by using the KVMTOOL=<path> environment variable." >&2
>> + return 2
>> + fi
>> + command -v $kvmtool
>> +}
>> +
>> initrd_create ()
>> {
>> if [ "$ENVIRON_DEFAULT" = "yes" ]; then
>> diff --git a/scripts/runtime.bash b/scripts/runtime.bash
>> index 132389c7dd59..23b238a6ab6f 100644
>> --- a/scripts/runtime.bash
>> +++ b/scripts/runtime.bash
>> @@ -12,14 +12,19 @@ extract_summary()
>> tail -3 | grep '^SUMMARY: ' | sed 's/^SUMMARY: /(/;s/'"$cr"'\{0,1\}$/)/'
>> }
>>
>> -# We assume that QEMU is going to work if it tried to load the kernel
>> +# We assume that QEMU/kvmtool is going to work if it tried to load the kernel
> assume that the VMM

Got it.

>
>> premature_failure()
>> {
>> local log="$(eval $(get_cmdline _NO_FILE_4Uhere_) 2>&1)"
>>
>> - echo "$log" | grep "_NO_FILE_4Uhere_" |
>> - grep -q -e "could not \(load\|open\) kernel" -e "error loading" &&
>> - return 1
>> + if [ "$TARGET" = "kvmtool" ]; then
>> + echo "$log" | grep "Fatal: unable to load firmware image _NO_FILE_4Uhere_" &&
>> + return 1
>> + else
>> + echo "$log" | grep "_NO_FILE_4Uhere_" |
>> + grep -q -e "could not \(load\|open\) kernel" -e "error loading" &&
>> + return 1
>> + fi
> Another place for a switch.
>
>>
>> RUNTIME_log_stderr <<< "$log"
>>
>> @@ -30,7 +35,14 @@ premature_failure()
>> get_cmdline()
>> {
>> local kernel=$1
>> - echo "TESTNAME=$testname TIMEOUT=$timeout ACCEL=$accel $RUNTIME_arch_run $kernel -smp $smp $opts"
>> + local smp_param
>> +
>> + if [ "$TARGET" = "kvmtool" ]; then
>> + smp_param="--cpus $smp"
>> + else
>> + smp_param="-smp $smp"
>> + fi
> switch
>
>> + echo "TESTNAME=$testname TIMEOUT=$timeout ACCEL=$accel $RUNTIME_arch_run $kernel $smp_param $opts"
>> }
>>
>> skip_nodefault()
>> @@ -70,6 +82,35 @@ function find_word()
>> grep -Fq " $1 " <<< " $2 "
>> }
>>
>> +fixup_kvmtool_opts()
>> +{
>> + local opts=$1
>> + local groups=$2
>> + local gic
>> + local gic_version
>> +
>> + if find_word "pmu" $groups; then
>> + opts+=" --pmu"
>> + fi
>> +
>> + if find_word "its" $groups; then
>> + gic_version=3
>> + gic="gicv3-its"
>> + elif [[ "$opts" =~ -machine\ *gic-version=(2|3) ]]; then
>> + gic_version="${BASH_REMATCH[1]}"
>> + gic="gicv$gic_version"
>> + fi
>> +
>> + if [ -n "$gic" ]; then
>> + opts=${opts/-machine gic-version=$gic_version/}
>> + opts+=" --irqchip=$gic"
>> + fi
>> +
>> + opts=${opts/-append/--params}
>> +
>> + echo "$opts"
>> +}
> Hmm, I don't think we want to write a QEMU parameter translator for
> all other VMMs, and all other VMM architectures, that we want to
> support. I think we should add new "extra_params" variables to the
> unittest configuration instead, e.g. "kvmtool_params", where the
> extra parameters can be listed correctly and explicitly. While at
> it, I would create an alias for "extra_params", which would be
> "qemu_params" allowing unittests that support more than one VMM
> to clearly show what's what.

I agree, this is a much better idea than a parameter translator. Using a dedicated
variable in unittests.cfg will make it easier for new tests to get support for all
VMMs (for example, writing a list of parameters in unittests.cfg should be easier
than digging through the scripts to figure exactly how and where to add a
translation for a new parameter), and it allow us to express parameters for other
VMMs which don't have a direct correspondent in qemu.

By creating an alias, do you mean replacing extra_params with qemu_params in
arm/unittests.cfg? Or something else?

>
>> +
>> function run()
>> {
>> local testname="$1"
>> @@ -105,7 +146,12 @@ function run()
>> return 2
>> fi
>>
>> - if [ -n "$accel" ] && [ -n "$ACCEL" ] && [ "$accel" != "$ACCEL" ]; then
>> + if [ "$TARGET" = "kvmtool" ]; then
>> + if [ -n "$accel" ] && [ "$accel" != "kvm" ]; then
>> + print_result "SKIP" $testname "" "$accel not supported by kvmtool"
>> + return 2
>> + fi
>> + elif [ -n "$accel" ] && [ -n "$ACCEL" ] && [ "$accel" != "$ACCEL" ]; then
> switch
>
>> print_result "SKIP" $testname "" "$accel only, but ACCEL=$ACCEL"
>> return 2
>> elif [ -n "$ACCEL" ]; then
>> @@ -126,6 +172,10 @@ function run()
>> done
>> fi
>>
>> + if [ "$TARGET" = "kvmtool" ]; then
>> + opts=$(fixup_kvmtool_opts "$opts" "$groups")
>> + fi
>> +
>> last_line=$(premature_failure > >(tail -1)) && {
>> print_result "SKIP" $testname "" "$last_line"
>> return 77
>> @@ -165,13 +215,25 @@ function run()
>> #
>> # Probe for MAX_SMP, in case it's less than the number of host cpus.
>> #
>> -# This probing currently only works for ARM, as x86 bails on another
>> -# error first. Also, this probing isn't necessary for any ARM hosts
>> -# running kernels later than v4.3, i.e. those including ef748917b52
>> -# "arm/arm64: KVM: Remove 'config KVM_ARM_MAX_VCPUS'". So, at some
>> -# point when maintaining the while loop gets too tiresome, we can
>> -# just remove it...
>> -while $RUNTIME_arch_run _NO_FILE_4Uhere_ -smp $MAX_SMP \
>> - |& grep -qi 'exceeds max CPUs'; do
>> - MAX_SMP=$((MAX_SMP >> 1))
>> -done
>> +# This probing currently only works for ARM, as x86 bails on another error
>> +# first. Also, this probing isn't necessary for any ARM hosts running kernels
>> +# later than v4.3, i.e. those including ef748917b52 "arm/arm64: KVM: Remove
>> +# 'config KVM_ARM_MAX_VCPUS'". So, at some point when maintaining the while loop
>> +# gets too tiresome, we can just remove it...
>> +#
>> +# We don't need this check for kvmtool, as kvmtool will automatically limit the
>> +# number of VCPUs to what the host supports instead of exiting with an error.
>> +# kvmtool prints a message when that happens, but it's harmless and the chance
>> +# of running a kernel so old that the number of VCPUs is smaller than the number
>> +# of physical CPUs is vanishingly small.
>> +#
>> +# For qemu this check is still needed. For qemu-system-aarch64 version 6.0.0,
>> +# using TCG, the maximum number of VCPUs that mach-virt supports is 8. If a test
>> +# is running on a recent x86 machine, there's a fairly good chance that more
>> +# than 8 logical CPUs are available.
>> +if [ "$TARGET" = "qemu" ]; then
>> + while $RUNTIME_arch_run _NO_FILE_4Uhere_ -smp $MAX_SMP \
>> + |& grep -qi 'exceeds max CPUs'; do
>> + MAX_SMP=$((MAX_SMP >> 1))
>> + done
>> +fi
>> diff --git a/scripts/mkstandalone.sh b/scripts/mkstandalone.sh
>> index cefdec30cb33..16f461c06842 100755
>> --- a/scripts/mkstandalone.sh
>> +++ b/scripts/mkstandalone.sh
>> @@ -95,6 +95,11 @@ function mkstandalone()
>> echo Written $standalone.
>> }
>>
>> +if [ "$TARGET" = "kvmtool" ]; then
>> + echo "Standalone tests not supported with kvmtool"
>> + exit 2
>> +fi
>> +
>> if [ "$ENVIRON_DEFAULT" = "yes" ] && [ "$ERRATATXT" ] && [ ! -f "$ERRATATXT" ]; then
>> echo "$ERRATATXT not found. (ERRATATXT=$ERRATATXT)" >&2
>> exit 2
>> diff --git a/arm/run b/arm/run
>> index a390ca5ae0ba..cc5890e7fec4 100755
>> --- a/arm/run
>> +++ b/arm/run
>> @@ -8,59 +8,81 @@ if [ -z "$STANDALONE" ]; then
>> source config.mak
>> source scripts/arch-run.bash
>> fi
>> -processor="$PROCESSOR"
>>
>> -ACCEL=$(get_qemu_accelerator) ||
>> - exit $?
>> +run_test_qemu()
>> +{
>> + processor="$PROCESSOR"
>>
>> -qemu=$(search_qemu_binary) ||
>> - exit $?
>> + ACCEL=$(get_qemu_accelerator) ||
>> + exit $?
>>
>> -if ! $qemu -machine '?' 2>&1 | grep 'ARM Virtual Machine' > /dev/null; then
>> - echo "$qemu doesn't support mach-virt ('-machine virt'). Exiting."
>> - exit 2
>> -fi
>> + qemu=$(search_qemu_binary) ||
>> + exit $?
>>
>> -M='-machine virt'
>> + if ! $qemu -machine '?' 2>&1 | grep 'ARM Virtual Machine' > /dev/null; then
>> + echo "$qemu doesn't support mach-virt ('-machine virt'). Exiting."
>> + exit 2
>> + fi
>>
>> -if [ "$ACCEL" = "kvm" ]; then
>> - if $qemu $M,\? 2>&1 | grep gic-version > /dev/null; then
>> - M+=',gic-version=host'
>> - fi
>> - if [ "$HOST" = "aarch64" ] || [ "$HOST" = "arm" ]; then
>> - processor="host"
>> - if [ "$ARCH" = "arm" ] && [ "$HOST" = "aarch64" ]; then
>> - processor+=",aarch64=off"
>> - fi
>> - fi
>> -fi
>> + M='-machine virt'
>>
>> -if [ "$ARCH" = "arm" ]; then
>> - M+=",highmem=off"
>> -fi
>> + if [ "$ACCEL" = "kvm" ]; then
>> + if $qemu $M,\? 2>&1 | grep gic-version > /dev/null; then
>> + M+=',gic-version=host'
>> + fi
>> + if [ "$HOST" = "aarch64" ] || [ "$HOST" = "arm" ]; then
>> + processor="host"
>> + if [ "$ARCH" = "arm" ] && [ "$HOST" = "aarch64" ]; then
>> + processor+=",aarch64=off"
>> + fi
>> + fi
>> + fi
>>
>> -if ! $qemu $M -device '?' 2>&1 | grep virtconsole > /dev/null; then
>> - echo "$qemu doesn't support virtio-console for chr-testdev. Exiting."
>> - exit 2
>> -fi
>> + if [ "$ARCH" = "arm" ]; then
>> + M+=",highmem=off"
>> + fi
>>
>> -if $qemu $M -chardev testdev,id=id -initrd . 2>&1 \
>> - | grep backend > /dev/null; then
>> - echo "$qemu doesn't support chr-testdev. Exiting."
>> - exit 2
>> -fi
>> + if ! $qemu $M -device '?' 2>&1 | grep virtconsole > /dev/null; then
>> + echo "$qemu doesn't support virtio-console for chr-testdev. Exiting."
>> + exit 2
>> + fi
>>
>> -chr_testdev='-device virtio-serial-device'
>> -chr_testdev+=' -device virtconsole,chardev=ctd -chardev testdev,id=ctd'
>> + if $qemu $M -chardev testdev,id=id -initrd . 2>&1 \
>> + | grep backend > /dev/null; then
>> + echo "$qemu doesn't support chr-testdev. Exiting."
>> + exit 2
>> + fi
>>
>> -pci_testdev=
>> -if $qemu $M -device '?' 2>&1 | grep pci-testdev > /dev/null; then
>> - pci_testdev="-device pci-testdev"
>> -fi
>> + chr_testdev='-device virtio-serial-device'
>> + chr_testdev+=' -device virtconsole,chardev=ctd -chardev testdev,id=ctd'
>> +
>> + pci_testdev=
>> + if $qemu $M -device '?' 2>&1 | grep pci-testdev > /dev/null; then
>> + pci_testdev="-device pci-testdev"
>> + fi
>> +
>> + M+=",accel=$ACCEL"
>> + command="$qemu -nodefaults $M -cpu $processor $chr_testdev $pci_testdev"
>> + command+=" -display none -serial stdio -kernel"
>> + command="$(migration_cmd) $(timeout_cmd) $command"
>> +
>> + run_qemu $command "$@"
>> +}
>> +
>> +run_test_kvmtool()
>> +{
>> + kvmtool=$(search_kvmtool_binary) ||
>> + exit $?
>>
>> -M+=",accel=$ACCEL"
>> -command="$qemu -nodefaults $M -cpu $processor $chr_testdev $pci_testdev"
>> -command+=" -display none -serial stdio -kernel"
>> -command="$(migration_cmd) $(timeout_cmd) $command"
>> + local command="$(timeout_cmd) $kvmtool run --firmware "
>> + run_test_status $command "$@"
>> +}
>>
>> -run_qemu $command "$@"
>> +case "$TARGET" in
>> + "qemu")
>> + run_test_qemu "$@"
>> + ;;
>> + "kvmtool")
>> + run_test_kvmtool "$@"
>> + ;;
>> +esac
> Hey, here's a switch :-) But I'd add a default case that errors out for
> good measure.

Yep, I think I made a mental note to replace if/else with this kind of switch
statement, but it slipped my mind in the end.

>
>> diff --git a/run_tests.sh b/run_tests.sh
>> index 65108e73a2c0..b010ee3ab348 100755
>> --- a/run_tests.sh
>> +++ b/run_tests.sh
>> @@ -26,7 +26,9 @@ Usage: $0 [-h] [-v] [-a] [-g group] [-j NUM-TASKS] [-t]
>> -t, --tap13 Output test results in TAP format
>>
>> Set the environment variable QEMU=/path/to/qemu-system-ARCH to
>> -specify the appropriate qemu binary for ARCH-run.
>> +specify the appropriate qemu binary for ARCH-run. For arm/arm64, kvmtool
>> +is also supported and the environment variable KVMTOOL=/path/to/kvmtool
>> +can be used to specify a custom location for the kvmtool binary.
> How about changing this last sentence (as a separate patch first) in usage
> to
>
> ENVIRONMENT
> QEMU Path to QEMU binary for ARCH-run
> ACCEL QEMU accelerator to use, e.g. "kvm", "hvf" or "tcg"
> TIMEOUT Timeout duration for the timeout(1) command
>
> And then in this patch adds
>
> KVMTOOL Path to KVMTOOL binary for ARCH-run

Sounds good, will do.

>
>>
>> EOF
>> }
>> @@ -41,6 +43,13 @@ if [ $? -ne 4 ]; then
>> exit 1
>> fi
>>
>> +if [ "$TARGET" = "kvmtool" ]; then
>> + if [ -n "$ACCEL" ] && [ "$ACCEL" != "kvm" ]; then
>> + echo "kvmtool supports only the kvm accelerator"
>> + exit 1
>> + fi
>> +fi
> I think this belongs in arm/run, because run_tests.sh isn't always used to
> run the tests.

Ok, I'll have a look and move this where it belongs.

Thanks,

Alex

>
>> +
>> only_tests=""
>> args=`getopt -u -o ag:htj:v -l all,group:,help,tap13,parallel:,verbose -- $*`
>> [ $? -ne 0 ] && exit 2;
>> --
>> 2.32.0
>>
> Thanks,
> drew
>