Re: [kvm-unit-tests PATCH v4 8/8] migration: add a migration selftest

Thomas Huth
2024-02-16T14:05:21Z

On 09/02/2024 10.11, Nicholas Piggin wrote:
> Add a selftest for migration support in guest library and test harness
> code. It performs migrations in a tight loop to irritate races and bugs
> in the test harness code.
>
> Include the test in arm, s390, powerpc.
>
> Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com> (s390x)
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> arm/Makefile.common | 1 +
> arm/selftest-migration.c | 1 +
> arm/unittests.cfg | 6 ++++++
> common/selftest-migration.c | 34 ++++++++++++++++++++++++++++++++++
> powerpc/Makefile.common | 1 +
> powerpc/selftest-migration.c | 1 +
> powerpc/unittests.cfg | 4 ++++
> s390x/Makefile | 1 +
> s390x/selftest-migration.c | 1 +
> s390x/unittests.cfg | 4 ++++
> 10 files changed, 54 insertions(+)
> create mode 120000 arm/selftest-migration.c
> create mode 100644 common/selftest-migration.c
> create mode 120000 powerpc/selftest-migration.c
> create mode 120000 s390x/selftest-migration.c
>
> diff --git a/arm/Makefile.common b/arm/Makefile.common
> index f828dbe0..f107c478 100644
> --- a/arm/Makefile.common
> +++ b/arm/Makefile.common
> @@ -5,6 +5,7 @@
> #
>
> tests-common = $(TEST_DIR)/selftest.$(exe)
> +tests-common += $(TEST_DIR)/selftest-migration.$(exe)
> tests-common += $(TEST_DIR)/spinlock-test.$(exe)
> tests-common += $(TEST_DIR)/pci-test.$(exe)
> tests-common += $(TEST_DIR)/pmu.$(exe)
> diff --git a/arm/selftest-migration.c b/arm/selftest-migration.c
> new file mode 120000
> index 00000000..bd1eb266
> --- /dev/null
> +++ b/arm/selftest-migration.c
> @@ -0,0 +1 @@
> +../common/selftest-migration.c
> \ No newline at end of file
> diff --git a/arm/unittests.cfg b/arm/unittests.cfg
> index fe601cbb..db0e4c9b 100644
> --- a/arm/unittests.cfg
> +++ b/arm/unittests.cfg
> @@ -55,6 +55,12 @@ smp = $MAX_SMP
> extra_params = -append 'smp'
> groups = selftest
>
> +# Test migration
> +[selftest-migration]
> +file = selftest-migration.flat
> +groups = selftest migration
> +arch = arm64
> +
> # Test PCI emulation
> [pci-test]
> file = pci-test.flat
> diff --git a/common/selftest-migration.c b/common/selftest-migration.c
> new file mode 100644
> index 00000000..f70c505f
> --- /dev/null
> +++ b/common/selftest-migration.c
> @@ -0,0 +1,34 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Machine independent migration tests
> + *
> + * This is just a very simple test that is intended to stress the migration
> + * support in the test harness. This could be expanded to test more guest
> + * library code, but architecture-specific tests should be used to test
> + * migration of tricky machine state.
> + */
> +#include <libcflat.h>
> +#include <migrate.h>
> +
> +#if defined(__arm__) || defined(__aarch64__)
> +/* arm can only call getchar 15 times */
> +#define NR_MIGRATIONS 15
> +#else
> +#define NR_MIGRATIONS 100
> +#endif

FYI, I just wrote a patch that will hopefully fix the limitation to 15 times
on arm:

https://lore.kernel.org/kvm/20240216140210.70280-1-thuth@redhat.com/T/#u

Thomas