| Message ID | 20230731102521.15335-7-avihaih@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vfio/migration: Add P2P support for VFIO migration | expand |
On 7/31/23 12:25, Avihai Horon wrote: > Now that P2P support has been added to VFIO migration, allow migration > of multiple devices if all of them support P2P migration. > > Single device migration is allowed regardless of P2P migration support. > > Signed-off-by: Avihai Horon <avihaih@nvidia.com> > Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Reviewed-by: Cédric Le Goater <clg@redhat.com> Thanks, C. > --- > hw/vfio/common.c | 26 ++++++++++++++++++-------- > 1 file changed, 18 insertions(+), 8 deletions(-) > > diff --git a/hw/vfio/common.c b/hw/vfio/common.c > index 7c3d636025..8a8d074e18 100644 > --- a/hw/vfio/common.c > +++ b/hw/vfio/common.c > @@ -363,21 +363,31 @@ bool vfio_mig_active(void) > > static Error *multiple_devices_migration_blocker; > > -static unsigned int vfio_migratable_device_num(void) > +/* > + * Multiple devices migration is allowed only if all devices support P2P > + * migration. Single device migration is allowed regardless of P2P migration > + * support. > + */ > +static bool vfio_multiple_devices_migration_is_supported(void) > { > VFIOGroup *group; > VFIODevice *vbasedev; > unsigned int device_num = 0; > + bool all_support_p2p = true; > > QLIST_FOREACH(group, &vfio_group_list, next) { > QLIST_FOREACH(vbasedev, &group->device_list, next) { > if (vbasedev->migration) { > device_num++; > + > + if (!(vbasedev->migration->mig_flags & VFIO_MIGRATION_P2P)) { > + all_support_p2p = false; > + } > } > } > } > > - return device_num; > + return all_support_p2p || device_num <= 1; > } > > int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp) > @@ -385,19 +395,19 @@ int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp) > int ret; > > if (multiple_devices_migration_blocker || > - vfio_migratable_device_num() <= 1) { > + vfio_multiple_devices_migration_is_supported()) { > return 0; > } > > if (vbasedev->enable_migration == ON_OFF_AUTO_ON) { > - error_setg(errp, "Migration is currently not supported with multiple " > - "VFIO devices"); > + error_setg(errp, "Multiple VFIO devices migration is supported only if " > + "all of them support P2P migration"); > return -EINVAL; > } > > error_setg(&multiple_devices_migration_blocker, > - "Migration is currently not supported with multiple " > - "VFIO devices"); > + "Multiple VFIO devices migration is supported only if all of " > + "them support P2P migration"); > ret = migrate_add_blocker(multiple_devices_migration_blocker, errp); > if (ret < 0) { > error_free(multiple_devices_migration_blocker); > @@ -410,7 +420,7 @@ int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp) > void vfio_unblock_multiple_devices_migration(void) > { > if (!multiple_devices_migration_blocker || > - vfio_migratable_device_num() > 1) { > + !vfio_multiple_devices_migration_is_supported()) { > return; > } >
diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 7c3d636025..8a8d074e18 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -363,21 +363,31 @@ bool vfio_mig_active(void) static Error *multiple_devices_migration_blocker; -static unsigned int vfio_migratable_device_num(void) +/* + * Multiple devices migration is allowed only if all devices support P2P + * migration. Single device migration is allowed regardless of P2P migration + * support. + */ +static bool vfio_multiple_devices_migration_is_supported(void) { VFIOGroup *group; VFIODevice *vbasedev; unsigned int device_num = 0; + bool all_support_p2p = true; QLIST_FOREACH(group, &vfio_group_list, next) { QLIST_FOREACH(vbasedev, &group->device_list, next) { if (vbasedev->migration) { device_num++; + + if (!(vbasedev->migration->mig_flags & VFIO_MIGRATION_P2P)) { + all_support_p2p = false; + } } } } - return device_num; + return all_support_p2p || device_num <= 1; } int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp) @@ -385,19 +395,19 @@ int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp) int ret; if (multiple_devices_migration_blocker || - vfio_migratable_device_num() <= 1) { + vfio_multiple_devices_migration_is_supported()) { return 0; } if (vbasedev->enable_migration == ON_OFF_AUTO_ON) { - error_setg(errp, "Migration is currently not supported with multiple " - "VFIO devices"); + error_setg(errp, "Multiple VFIO devices migration is supported only if " + "all of them support P2P migration"); return -EINVAL; } error_setg(&multiple_devices_migration_blocker, - "Migration is currently not supported with multiple " - "VFIO devices"); + "Multiple VFIO devices migration is supported only if all of " + "them support P2P migration"); ret = migrate_add_blocker(multiple_devices_migration_blocker, errp); if (ret < 0) { error_free(multiple_devices_migration_blocker); @@ -410,7 +420,7 @@ int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp) void vfio_unblock_multiple_devices_migration(void) { if (!multiple_devices_migration_blocker || - vfio_migratable_device_num() > 1) { + !vfio_multiple_devices_migration_is_supported()) { return; }