| Message ID | 20230630073637.124234-4-zhenzhong.duan@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | VFIO migration related refactor and bug fix | expand |
On 30/06/2023 08:36, Zhenzhong Duan wrote: > vIOMMU migration blocker can be consolidated to per device default > blocker, then some vIOMMU global blocker related functions and data > could be removed. > Perhaps expand to something like below on the why it justifies the consolidation: Contrary to multiple device blocker which needs to consider already-attached devices to unblock/block dynamically, the vIOMMU migration blocker is a device specific config. Meaning it only needs to know whether the device is bypassing or not the vIOMMU (via machine property, or per pxb-pcie::bypass_iommu), and does not need the state of currently present devices. For this reason, the vIOMMU global migration blocker can be consolidated into the per-device migration blocker, allowing us to remove some unnecessary code. > This change also makes vfio_mig_active() more accurate as it doesn't > check for global blocker. > Cool callout. > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> With above adjustment: Reviewed-by: Joao Martins <joao.m.martins@oracle.com> > --- > hw/vfio/common.c | 51 ++--------------------------------- > hw/vfio/migration.c | 7 ++--- > hw/vfio/pci.c | 1 - > include/hw/vfio/vfio-common.h | 3 +-- > 4 files changed, 7 insertions(+), 55 deletions(-) > > diff --git a/hw/vfio/common.c b/hw/vfio/common.c > index 00fef5aa08be..a8439447b990 100644 > --- a/hw/vfio/common.c > +++ b/hw/vfio/common.c > @@ -362,7 +362,6 @@ bool vfio_mig_active(void) > } > > static Error *multiple_devices_migration_blocker; > -static Error *giommu_migration_blocker; > > static unsigned int vfio_migratable_device_num(void) > { > @@ -420,55 +419,9 @@ void vfio_unblock_multiple_devices_migration(void) > multiple_devices_migration_blocker = NULL; > } > > -static bool vfio_viommu_preset(void) > +bool vfio_viommu_preset(VFIODevice *vbasedev) > { > - VFIOAddressSpace *space; > - > - QLIST_FOREACH(space, &vfio_address_spaces, list) { > - if (space->as != &address_space_memory) { > - return true; > - } > - } > - > - return false; > -} > - > -bool vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp) > -{ > - int ret; > - > - if (giommu_migration_blocker || > - !vfio_viommu_preset()) { > - return true; > - } > - > - if (vbasedev->enable_migration == ON_OFF_AUTO_ON) { > - error_setg(errp, > - "Migration is currently not supported with vIOMMU enabled"); > - return false; > - } > - > - error_setg(&giommu_migration_blocker, > - "Migration is currently not supported with vIOMMU enabled"); > - ret = migrate_add_blocker(giommu_migration_blocker, errp); > - if (ret < 0) { > - error_free(giommu_migration_blocker); > - giommu_migration_blocker = NULL; > - } > - > - return !ret; > -} > - > -void vfio_migration_finalize(void) > -{ > - if (!giommu_migration_blocker || > - vfio_viommu_preset()) { > - return; > - } > - > - migrate_del_blocker(giommu_migration_blocker); > - error_free(giommu_migration_blocker); > - giommu_migration_blocker = NULL; > + return vbasedev->group->container->space->as != &address_space_memory; > } > > static void vfio_set_migration_error(int err) > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > index 09fa4714a085..80509958f0d3 100644 > --- a/hw/vfio/migration.c > +++ b/hw/vfio/migration.c > @@ -883,9 +883,10 @@ bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp) > return ret; > } > > - ret = vfio_block_giommu_migration(vbasedev, errp); > - if (!ret) { > - return ret; > + if (vfio_viommu_preset(vbasedev)) { > + error_setg(&err, "%s: Migration is currently not supported " > + "with vIOMMU enabled", vbasedev->name); > + return vfio_block_migration(vbasedev, err, errp); > } > > trace_vfio_migration_realize(vbasedev->name); > diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c > index 31c4ab250fbe..c2cf7454ece6 100644 > --- a/hw/vfio/pci.c > +++ b/hw/vfio/pci.c > @@ -3255,7 +3255,6 @@ static void vfio_instance_finalize(Object *obj) > */ > vfio_put_device(vdev); > vfio_put_group(group); > - vfio_migration_finalize(); > } > > static void vfio_exitfn(PCIDevice *pdev) > diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h > index b3014ece2edf..3c18572322fc 100644 > --- a/include/hw/vfio/vfio-common.h > +++ b/include/hw/vfio/vfio-common.h > @@ -227,7 +227,7 @@ extern VFIOGroupList vfio_group_list; > bool vfio_mig_active(void); > bool vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp); > void vfio_unblock_multiple_devices_migration(void); > -bool vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp); > +bool vfio_viommu_preset(VFIODevice *vbasedev); > int64_t vfio_mig_bytes_transferred(void); > void vfio_reset_bytes_transferred(void); > > @@ -254,6 +254,5 @@ int vfio_spapr_remove_window(VFIOContainer *container, > > bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp); > void vfio_migration_exit(VFIODevice *vbasedev); > -void vfio_migration_finalize(void); > > #endif /* HW_VFIO_VFIO_COMMON_H */
>-----Original Message----- >From: Joao Martins <joao.m.martins@oracle.com> >Sent: Friday, June 30, 2023 7:17 PM >Subject: Re: [PATCH v5 5/7] vfio/migration: Change vIOMMU blocker from >global to per device > >On 30/06/2023 08:36, Zhenzhong Duan wrote: >> vIOMMU migration blocker can be consolidated to per device default >> blocker, then some vIOMMU global blocker related functions and data >> could be removed. >> >Perhaps expand to something like below on the why it justifies the >consolidation: > >Contrary to multiple device blocker which needs to consider already-attached >devices to unblock/block dynamically, the vIOMMU migration blocker is a >device >specific config. Meaning it only needs to know whether the device is bypassing >or not the vIOMMU (via machine property, or per pxb-pcie::bypass_iommu), >and >does not need the state of currently present devices. For this reason, the >vIOMMU global migration blocker can be consolidated into the per-device >migration blocker, allowing us to remove some unnecessary code. Great, will use this words. Thanks Zhenzhong
diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 00fef5aa08be..a8439447b990 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -362,7 +362,6 @@ bool vfio_mig_active(void) } static Error *multiple_devices_migration_blocker; -static Error *giommu_migration_blocker; static unsigned int vfio_migratable_device_num(void) { @@ -420,55 +419,9 @@ void vfio_unblock_multiple_devices_migration(void) multiple_devices_migration_blocker = NULL; } -static bool vfio_viommu_preset(void) +bool vfio_viommu_preset(VFIODevice *vbasedev) { - VFIOAddressSpace *space; - - QLIST_FOREACH(space, &vfio_address_spaces, list) { - if (space->as != &address_space_memory) { - return true; - } - } - - return false; -} - -bool vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp) -{ - int ret; - - if (giommu_migration_blocker || - !vfio_viommu_preset()) { - return true; - } - - if (vbasedev->enable_migration == ON_OFF_AUTO_ON) { - error_setg(errp, - "Migration is currently not supported with vIOMMU enabled"); - return false; - } - - error_setg(&giommu_migration_blocker, - "Migration is currently not supported with vIOMMU enabled"); - ret = migrate_add_blocker(giommu_migration_blocker, errp); - if (ret < 0) { - error_free(giommu_migration_blocker); - giommu_migration_blocker = NULL; - } - - return !ret; -} - -void vfio_migration_finalize(void) -{ - if (!giommu_migration_blocker || - vfio_viommu_preset()) { - return; - } - - migrate_del_blocker(giommu_migration_blocker); - error_free(giommu_migration_blocker); - giommu_migration_blocker = NULL; + return vbasedev->group->container->space->as != &address_space_memory; } static void vfio_set_migration_error(int err) diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index 09fa4714a085..80509958f0d3 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -883,9 +883,10 @@ bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp) return ret; } - ret = vfio_block_giommu_migration(vbasedev, errp); - if (!ret) { - return ret; + if (vfio_viommu_preset(vbasedev)) { + error_setg(&err, "%s: Migration is currently not supported " + "with vIOMMU enabled", vbasedev->name); + return vfio_block_migration(vbasedev, err, errp); } trace_vfio_migration_realize(vbasedev->name); diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 31c4ab250fbe..c2cf7454ece6 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -3255,7 +3255,6 @@ static void vfio_instance_finalize(Object *obj) */ vfio_put_device(vdev); vfio_put_group(group); - vfio_migration_finalize(); } static void vfio_exitfn(PCIDevice *pdev) diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index b3014ece2edf..3c18572322fc 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -227,7 +227,7 @@ extern VFIOGroupList vfio_group_list; bool vfio_mig_active(void); bool vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp); void vfio_unblock_multiple_devices_migration(void); -bool vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp); +bool vfio_viommu_preset(VFIODevice *vbasedev); int64_t vfio_mig_bytes_transferred(void); void vfio_reset_bytes_transferred(void); @@ -254,6 +254,5 @@ int vfio_spapr_remove_window(VFIOContainer *container, bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp); void vfio_migration_exit(VFIODevice *vbasedev); -void vfio_migration_finalize(void); #endif /* HW_VFIO_VFIO_COMMON_H */
vIOMMU migration blocker can be consolidated to per device default blocker, then some vIOMMU global blocker related functions and data could be removed. This change also makes vfio_mig_active() more accurate as it doesn't check for global blocker. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> --- hw/vfio/common.c | 51 ++--------------------------------- hw/vfio/migration.c | 7 ++--- hw/vfio/pci.c | 1 - include/hw/vfio/vfio-common.h | 3 +-- 4 files changed, 7 insertions(+), 55 deletions(-)