On Mon, 29 May 2017 15:55:16 +0200
Halil Pasic <pa...@linux.vnet.ibm.com> wrote:
> Currently the migration of the channel subsystem (css) is only partial
> and is done by the virtio ccw proxies -- the only migratable css devices
extra blank ---------------------------------------------------^
> existing at the moment.
>
> With the current work on emulated and passthrough devices we need to
> decouple the migration of the channel subsystem state from virtio ccw,
> and have a separate section for it. A new section however necessarily
> breaks the migration compatibility.
>
> So let us introduce a switch at the machine class, and put it in 'off'
> state for now. We will turn the switch 'on' for future machines once all
> preparations are met. For compatibility machines the switch will stay
> 'off'.
>
> Signed-off-by: Halil Pasic <pa...@linux.vnet.ibm.com>
> ---
> hw/s390x/s390-virtio-ccw.c | 13 +++++++++++++
> include/hw/s390x/s390-virtio-ccw.h | 7 +++++++
> 2 files changed, 20 insertions(+)
>
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index 04148916ed..95256d3982 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -196,6 +196,7 @@ static void ccw_machine_class_init(ObjectClass *oc, void
> *data)
>
> s390mc->ri_allowed = true;
> s390mc->cpu_model_allowed = true;
> + s390mc->css_migration_enabled = false; /* TODO: set to true */
> mc->init = ccw_init;
> mc->reset = s390_machine_reset;
> mc->hot_add_cpu = s390_hot_add_cpu;
> @@ -344,6 +345,11 @@ static const TypeInfo ccw_machine_info = {
> },
> };
>
> +bool css_migration_enabled(void)
> +{
> + return get_machine_class()->css_migration_enabled;
> +}
> +
> #define DEFINE_CCW_MACHINE(suffix, verstr, latest)
> \
> static void ccw_machine_##suffix##_class_init(ObjectClass *oc,
> \
> void *data)
> \
> @@ -445,6 +451,10 @@ static const TypeInfo ccw_machine_info = {
>
> static void ccw_machine_2_10_instance_options(MachineState *machine)
> {
> + /*
> + * TODO Once preparations are done register vmstate for the css if
> + * css_migration_enabled().
> + */
> }
>
> static void ccw_machine_2_10_class_options(MachineClass *mc)
> @@ -459,8 +469,11 @@ static void
> ccw_machine_2_9_instance_options(MachineState *machine)
>
> static void ccw_machine_2_9_class_options(MachineClass *mc)
> {
> + S390CcwMachineClass *s390mc = S390_MACHINE_CLASS(mc);
> +
> ccw_machine_2_10_class_options(mc);
> SET_MACHINE_COMPAT(mc, CCW_COMPAT_2_9);
> + s390mc->css_migration_enabled = false;
> }
> DEFINE_CCW_MACHINE(2_9, "2.9", false);
>
> diff --git a/include/hw/s390x/s390-virtio-ccw.h
> b/include/hw/s390x/s390-virtio-ccw.h
> index 7b8a3e4d74..e9c4f4182b 100644
> --- a/include/hw/s390x/s390-virtio-ccw.h
> +++ b/include/hw/s390x/s390-virtio-ccw.h
> @@ -38,6 +38,7 @@ typedef struct S390CcwMachineClass {
> /*< public >*/
> bool ri_allowed;
> bool cpu_model_allowed;
> + bool css_migration_enabled;
> } S390CcwMachineClass;
>
> /* runtime-instrumentation allowed by the machine */
> @@ -45,4 +46,10 @@ bool ri_allowed(void);
> /* cpu model allowed by the machine */
> bool cpu_model_allowed(void);
>
> +/**
> + * Returns true if (vmstate based) migration of the channel subsystem
> + * is enabled, false if it is disabled.
> + */
> +bool css_migration_enabled(void);
> +
> #endif
Acked-by: Cornelia Huck <cornelia.h...@de.ibm.com>
