| Message ID | 20170505173507.74077-10-pasic@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Halil Pasic (pasic@linux.vnet.ibm.com) wrote: > Turn on migration for the channel subsystem and the new scheme for > migrating virtio-ccw proxy devices (instead of letting the transport > independent child device migrate it's proxy, use the usual > DeviceClass.vmsd mechanism) for future machine versions. > > The vmstate based migration of the channel subsystem is not migration > stream compatible with the method for handling migration of legacy > machines. > > Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com> > Reviewed-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com> > --- > hw/s390x/ccw-device.c | 1 + > hw/s390x/css.c | 5 +++++ > hw/s390x/s390-virtio-ccw.c | 9 ++++----- > hw/s390x/virtio-ccw.c | 14 ++++++++++++++ > include/hw/s390x/css.h | 4 ++++ > 5 files changed, 28 insertions(+), 5 deletions(-) > > diff --git a/hw/s390x/ccw-device.c b/hw/s390x/ccw-device.c > index f9bfa15..3b5df03 100644 > --- a/hw/s390x/ccw-device.c > +++ b/hw/s390x/ccw-device.c > @@ -48,6 +48,7 @@ static void ccw_device_class_init(ObjectClass *klass, void *data) > k->realize = ccw_device_realize; > k->refill_ids = ccw_device_refill_ids; > dc->props = ccw_device_properties; > + dc->vmsd = &vmstate_ccw_dev; > } > > const VMStateDescription vmstate_ccw_dev = { > diff --git a/hw/s390x/css.c b/hw/s390x/css.c > index d9a0fb9..b58832a 100644 > --- a/hw/s390x/css.c > +++ b/hw/s390x/css.c > @@ -385,6 +385,11 @@ static int subch_dev_post_load(void *opaque, int version_id) > return 0; > } > > +void css_register_vmstate(void) > +{ > + vmstate_register(NULL, 0, &vmstate_css, &channel_subsys); > +} > + Why isn't that attached to a device vmsd? > IndAddr *get_indicator(hwaddr ind_addr, int len) > { > IndAddr *indicator; > diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c > index 698e8fc..5307f59 100644 > --- a/hw/s390x/s390-virtio-ccw.c > +++ b/hw/s390x/s390-virtio-ccw.c > @@ -196,7 +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 */ > + s390mc->css_migration_enabled = true; > mc->init = ccw_init; > mc->reset = s390_machine_reset; > mc->hot_add_cpu = s390_hot_add_cpu; > @@ -414,10 +414,9 @@ bool css_migration_enabled(void) > > static void ccw_machine_2_10_instance_options(MachineState *machine) > { > - /* > - * TODO Once preparations are done register vmstate for the css if > - * css_migration_enabled(). > - */ > + if (css_migration_enabled()) { > + css_register_vmstate(); > + } > } > > static void ccw_machine_2_10_class_options(MachineClass *mc) > diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c > index 8ab655c..c611b6f 100644 > --- a/hw/s390x/virtio-ccw.c > +++ b/hw/s390x/virtio-ccw.c > @@ -1307,6 +1307,10 @@ static void virtio_ccw_save_config(DeviceState *d, QEMUFile *f) > { > VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); > > + if (css_migration_enabled()) { > + /* we migrate via DeviceClass.vmsd */ > + return; > + } > /* > * We save in legacy mode. The components take care of their own > * compat. representation (based on css_migration_enabled). > @@ -1318,6 +1322,10 @@ static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f) > { > VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); > > + if (css_migration_enabled()) { > + /* we migrate via DeviceClass.vmsd */ > + return 0; > + } > /* > * We load in legacy mode. The components take take care to read > * only stuff which is actually there (based on css_migration_enabled). > @@ -1365,6 +1373,11 @@ static void virtio_ccw_device_plugged(DeviceState *d, Error **errp) > sch->id.cu_model = virtio_bus_get_vdev_id(&dev->bus); > > > + /* Avoid generating unknown section for legacy migration target. */ > + if (!css_migration_enabled()) { > + DEVICE_GET_CLASS(ccw_dev)->vmsd = NULL; > + } > + That's a very odd thing to do; can't you use a .needed at the top level of the vmstate_virtio_ccw_dev to avoid having to set it to NULL like this? > css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid, > d->hotplugged, 1); > } > @@ -1657,6 +1670,7 @@ static void virtio_ccw_device_class_init(ObjectClass *klass, void *data) > dc->realize = virtio_ccw_busdev_realize; > dc->exit = virtio_ccw_busdev_exit; > dc->bus_type = TYPE_VIRTUAL_CSS_BUS; > + dc->vmsd = &vmstate_virtio_ccw_dev; > } > > static const TypeInfo virtio_ccw_device_info = { > diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h > index dbe093e..be5eb81 100644 > --- a/include/hw/s390x/css.h > +++ b/include/hw/s390x/css.h > @@ -207,4 +207,8 @@ extern PropertyInfo css_devid_ro_propinfo; > * is responsible for unregistering and freeing it. > */ > SubchDev *css_create_virtual_sch(CssDevId bus_id, Error **errp); > + > +/** Turn on css migration */ > +void css_register_vmstate(void); > + > #endif > -- > 2.10.2 Dave -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
On 05/08/2017 07:27 PM, Dr. David Alan Gilbert wrote: > * Halil Pasic (pasic@linux.vnet.ibm.com) wrote: >> Turn on migration for the channel subsystem and the new scheme for >> migrating virtio-ccw proxy devices (instead of letting the transport >> independent child device migrate it's proxy, use the usual >> DeviceClass.vmsd mechanism) for future machine versions. [..] >> +void css_register_vmstate(void) >> +{ >> + vmstate_register(NULL, 0, &vmstate_css, &channel_subsys); >> +} >> + > > Why isn't that attached to a device vmsd? Because there is no device. The channel subsystem is not modeled as a QEMU device but it does have state which needs to be migrated. [..] >> @@ -1365,6 +1373,11 @@ static void virtio_ccw_device_plugged(DeviceState *d, Error **errp) >> sch->id.cu_model = virtio_bus_get_vdev_id(&dev->bus); >> >> >> + /* Avoid generating unknown section for legacy migration target. */ >> + if (!css_migration_enabled()) { >> + DEVICE_GET_CLASS(ccw_dev)->vmsd = NULL; >> + } >> + > > That's a very odd thing to do; can't you use a .needed at the > top level of the vmstate_virtio_ccw_dev to avoid having to > set it to NULL like this? > I agree it's odd. As far as I remember I can't use .needed but I will double check. Many thanks for your review! Halil
* Halil Pasic (pasic@linux.vnet.ibm.com) wrote: > > > On 05/08/2017 07:27 PM, Dr. David Alan Gilbert wrote: > > * Halil Pasic (pasic@linux.vnet.ibm.com) wrote: > >> Turn on migration for the channel subsystem and the new scheme for > >> migrating virtio-ccw proxy devices (instead of letting the transport > >> independent child device migrate it's proxy, use the usual > >> DeviceClass.vmsd mechanism) for future machine versions. > > [..] > > >> +void css_register_vmstate(void) > >> +{ > >> + vmstate_register(NULL, 0, &vmstate_css, &channel_subsys); > >> +} > >> + > > > > Why isn't that attached to a device vmsd? > > Because there is no device. The channel subsystem is not modeled > as a QEMU device but it does have state which needs to be > migrated. Ah OK. > [..] > > >> @@ -1365,6 +1373,11 @@ static void virtio_ccw_device_plugged(DeviceState *d, Error **errp) > >> sch->id.cu_model = virtio_bus_get_vdev_id(&dev->bus); > >> > >> > >> + /* Avoid generating unknown section for legacy migration target. */ > >> + if (!css_migration_enabled()) { > >> + DEVICE_GET_CLASS(ccw_dev)->vmsd = NULL; > >> + } > >> + > > > > That's a very odd thing to do; can't you use a .needed at the > > top level of the vmstate_virtio_ccw_dev to avoid having to > > set it to NULL like this? > > > > I agree it's odd. As far as I remember I can't use .needed but > I will double check. You can have top level .needed's - both vmstate_globalstate in migration.c and colo's colo_state use them. Dave > Many thanks for your review! > > Halil > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
On 05/08/2017 08:37 PM, Dr. David Alan Gilbert wrote: > * Halil Pasic (pasic@linux.vnet.ibm.com) wrote: >> >> >> On 05/08/2017 07:27 PM, Dr. David Alan Gilbert wrote: >>> * Halil Pasic (pasic@linux.vnet.ibm.com) wrote: >>>> Turn on migration for the channel subsystem and the new scheme for >>>> migrating virtio-ccw proxy devices (instead of letting the transport >>>> independent child device migrate it's proxy, use the usual >>>> DeviceClass.vmsd mechanism) for future machine versions. >> >> [..] >> >>>> @@ -1365,6 +1373,11 @@ static void virtio_ccw_device_plugged(DeviceState *d, Error **errp) >>>> sch->id.cu_model = virtio_bus_get_vdev_id(&dev->bus); >>>> >>>> >>>> + /* Avoid generating unknown section for legacy migration target. */ >>>> + if (!css_migration_enabled()) { >>>> + DEVICE_GET_CLASS(ccw_dev)->vmsd = NULL; >>>> + } >>>> + >>> >>> That's a very odd thing to do; can't you use a .needed at the >>> top level of the vmstate_virtio_ccw_dev to avoid having to >>> set it to NULL like this? >>> >> >> I agree it's odd. As far as I remember I can't use .needed but >> I will double check. > > You can have top level .needed's - both vmstate_globalstate in > migration.c and colo's colo_state use them. > Works like charm. I'm really happy to get rid of this ugly hunk. Thanks a lot! I was probably confused by the fact that I want to use the same vmsd with vmstate_save_state when the needed is false. That works, but I have probably blindly assumed (back then) it does not. Of course it does make sense to ignore .needed in that function, because for a vmsd coming from a recursive call while processing a filed then the non-presence of a field should be indicated by field_exists. I wonder if adding a comment at the definition site would be helpful. Something like: struct VMStateDescription { .... void (*pre_save)(void *opaque); + /* Controls the existence of sections and subsections, but not fields. */ bool (*needed)(void *opaque); VMStateField *fields; const VMStateDescription **subsections; }; Halil > Dave > >> Many thanks for your review! >> >> Halil >> > -- > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK >
diff --git a/hw/s390x/ccw-device.c b/hw/s390x/ccw-device.c index f9bfa15..3b5df03 100644 --- a/hw/s390x/ccw-device.c +++ b/hw/s390x/ccw-device.c @@ -48,6 +48,7 @@ static void ccw_device_class_init(ObjectClass *klass, void *data) k->realize = ccw_device_realize; k->refill_ids = ccw_device_refill_ids; dc->props = ccw_device_properties; + dc->vmsd = &vmstate_ccw_dev; } const VMStateDescription vmstate_ccw_dev = { diff --git a/hw/s390x/css.c b/hw/s390x/css.c index d9a0fb9..b58832a 100644 --- a/hw/s390x/css.c +++ b/hw/s390x/css.c @@ -385,6 +385,11 @@ static int subch_dev_post_load(void *opaque, int version_id) return 0; } +void css_register_vmstate(void) +{ + vmstate_register(NULL, 0, &vmstate_css, &channel_subsys); +} + IndAddr *get_indicator(hwaddr ind_addr, int len) { IndAddr *indicator; diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c index 698e8fc..5307f59 100644 --- a/hw/s390x/s390-virtio-ccw.c +++ b/hw/s390x/s390-virtio-ccw.c @@ -196,7 +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 */ + s390mc->css_migration_enabled = true; mc->init = ccw_init; mc->reset = s390_machine_reset; mc->hot_add_cpu = s390_hot_add_cpu; @@ -414,10 +414,9 @@ bool css_migration_enabled(void) static void ccw_machine_2_10_instance_options(MachineState *machine) { - /* - * TODO Once preparations are done register vmstate for the css if - * css_migration_enabled(). - */ + if (css_migration_enabled()) { + css_register_vmstate(); + } } static void ccw_machine_2_10_class_options(MachineClass *mc) diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c index 8ab655c..c611b6f 100644 --- a/hw/s390x/virtio-ccw.c +++ b/hw/s390x/virtio-ccw.c @@ -1307,6 +1307,10 @@ static void virtio_ccw_save_config(DeviceState *d, QEMUFile *f) { VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); + if (css_migration_enabled()) { + /* we migrate via DeviceClass.vmsd */ + return; + } /* * We save in legacy mode. The components take care of their own * compat. representation (based on css_migration_enabled). @@ -1318,6 +1322,10 @@ static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f) { VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); + if (css_migration_enabled()) { + /* we migrate via DeviceClass.vmsd */ + return 0; + } /* * We load in legacy mode. The components take take care to read * only stuff which is actually there (based on css_migration_enabled). @@ -1365,6 +1373,11 @@ static void virtio_ccw_device_plugged(DeviceState *d, Error **errp) sch->id.cu_model = virtio_bus_get_vdev_id(&dev->bus); + /* Avoid generating unknown section for legacy migration target. */ + if (!css_migration_enabled()) { + DEVICE_GET_CLASS(ccw_dev)->vmsd = NULL; + } + css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid, d->hotplugged, 1); } @@ -1657,6 +1670,7 @@ static void virtio_ccw_device_class_init(ObjectClass *klass, void *data) dc->realize = virtio_ccw_busdev_realize; dc->exit = virtio_ccw_busdev_exit; dc->bus_type = TYPE_VIRTUAL_CSS_BUS; + dc->vmsd = &vmstate_virtio_ccw_dev; } static const TypeInfo virtio_ccw_device_info = { diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h index dbe093e..be5eb81 100644 --- a/include/hw/s390x/css.h +++ b/include/hw/s390x/css.h @@ -207,4 +207,8 @@ extern PropertyInfo css_devid_ro_propinfo; * is responsible for unregistering and freeing it. */ SubchDev *css_create_virtual_sch(CssDevId bus_id, Error **errp); + +/** Turn on css migration */ +void css_register_vmstate(void); + #endif