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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=alex.williamson@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=alex.williamson@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/25 01:07:33 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.199, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: cohuck@redhat.com, cjia@nvidia.com, aik@ozlabs.ru, Zhengxiao.zx@Alibaba-inc.com, shuangtai.tst@alibaba-inc.com, qemu-devel@nongnu.org, peterx@redhat.com, eauger@redhat.com, yi.l.liu@intel.com, quintela@redhat.com, ziye.yang@intel.com, armbru@redhat.com, mlevitsk@redhat.com, pasic@linux.ibm.com, felipe@nutanix.com, zhi.a.wang@intel.com, kevin.tian@intel.com, yan.y.zhao@intel.com, dgilbert@redhat.com, changpeng.liu@intel.com, eskultet@redhat.com, Ken.Xue@amd.com, jonathan.davies@nutanix.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, 23 Sep 2020 04:54:09 +0530 Kirti Wankhede wrote: > Define flags to be used as delimeter in migration file stream. > Added .save_setup and .save_cleanup functions. Mapped & unmapped migration > region from these functions at source during saving or pre-copy phase. > Set VFIO device state depending on VM's state. During live migration, VM is > running when .save_setup is called, _SAVING | _RUNNING state is set for VFIO > device. During save-restore, VM is paused, _SAVING state is set for VFIO device. > > Signed-off-by: Kirti Wankhede > Reviewed-by: Neo Jia > --- > hw/vfio/migration.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > hw/vfio/trace-events | 2 ++ > 2 files changed, 93 insertions(+) > > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > index f650fe9fc3c8..8e8adaa25779 100644 > --- a/hw/vfio/migration.c > +++ b/hw/vfio/migration.c > @@ -8,12 +8,15 @@ > */ > > #include "qemu/osdep.h" > +#include "qemu/main-loop.h" > +#include "qemu/cutils.h" > #include > > #include "sysemu/runstate.h" > #include "hw/vfio/vfio-common.h" > #include "cpu.h" > #include "migration/migration.h" > +#include "migration/vmstate.h" > #include "migration/qemu-file.h" > #include "migration/register.h" > #include "migration/blocker.h" > @@ -25,6 +28,17 @@ > #include "trace.h" > #include "hw/hw.h" > > +/* > + * Flags used as delimiter: > + * 0xffffffff => MSB 32-bit all 1s > + * 0xef10 => emulated (virtual) function IO > + * 0x0000 => 16-bits reserved for flags > + */ > +#define VFIO_MIG_FLAG_END_OF_STATE (0xffffffffef100001ULL) > +#define VFIO_MIG_FLAG_DEV_CONFIG_STATE (0xffffffffef100002ULL) > +#define VFIO_MIG_FLAG_DEV_SETUP_STATE (0xffffffffef100003ULL) > +#define VFIO_MIG_FLAG_DEV_DATA_STATE (0xffffffffef100004ULL) > + > static inline int vfio_mig_access(VFIODevice *vbasedev, void *val, int count, > off_t off, bool iswrite) > { > @@ -166,6 +180,65 @@ static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t mask, > return 0; > } > > +/* ---------------------------------------------------------------------- */ > + > +static int vfio_save_setup(QEMUFile *f, void *opaque) > +{ > + VFIODevice *vbasedev = opaque; > + VFIOMigration *migration = vbasedev->migration; > + int ret; > + > + trace_vfio_save_setup(vbasedev->name); > + > + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_SETUP_STATE); > + > + if (migration->region.mmaps) { > + qemu_mutex_lock_iothread(); > + ret = vfio_region_mmap(&migration->region); > + qemu_mutex_unlock_iothread(); Please add a comment identifying why the iothread mutex lock is necessary here. > + if (ret) { > + error_report("%s: Failed to mmap VFIO migration region %d: %s", > + vbasedev->name, migration->region.nr, We don't support multiple migration regions, is it useful to include the region index here? > + strerror(-ret)); > + error_report("%s: Falling back to slow path", vbasedev->name); > + } > + } > + > + ret = vfio_migration_set_state(vbasedev, VFIO_DEVICE_STATE_MASK, > + VFIO_DEVICE_STATE_SAVING); > + if (ret) { > + error_report("%s: Failed to set state SAVING", vbasedev->name); > + return ret; > + } Again, doesn't match the function semantics that success only means the device is in a non-error state, maybe the one that was asked for. > + > + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); What's the overall purpose of writing these markers into the migration stream? vfio_load_state() doesn't do anything with this other than validate that the end-of-state immediately follows. Is this a placeholder for something in the future? > + > + ret = qemu_file_get_error(f); > + if (ret) { > + return ret; > + } > + > + return 0; > +} > + > +static void vfio_save_cleanup(void *opaque) > +{ > + VFIODevice *vbasedev = opaque; > + VFIOMigration *migration = vbasedev->migration; > + > + if (migration->region.mmaps) { > + vfio_region_unmap(&migration->region); > + } > + trace_vfio_save_cleanup(vbasedev->name); > +} > + > +static SaveVMHandlers savevm_vfio_handlers = { > + .save_setup = vfio_save_setup, > + .save_cleanup = vfio_save_cleanup, > +}; > + > +/* ---------------------------------------------------------------------- */ > + > static void vfio_vmstate_change(void *opaque, int running, RunState state) > { > VFIODevice *vbasedev = opaque; > @@ -225,6 +298,8 @@ static int vfio_migration_init(VFIODevice *vbasedev, > struct vfio_region_info *info) > { > int ret = -EINVAL; > + char id[256] = ""; > + Object *obj; > > if (!vbasedev->ops->vfio_get_object) { > return ret; > @@ -241,6 +316,22 @@ static int vfio_migration_init(VFIODevice *vbasedev, > return ret; > } > > + obj = vbasedev->ops->vfio_get_object(vbasedev); > + > + if (obj) { > + DeviceState *dev = DEVICE(obj); > + char *oid = vmstate_if_get_id(VMSTATE_IF(dev)); > + > + if (oid) { > + pstrcpy(id, sizeof(id), oid); > + pstrcat(id, sizeof(id), "/"); > + g_free(oid); > + } > + } Here's where vfio_migration_init() starts using vfio_get_object() as I referenced back on patch 04. We might as well get the object before calling vfio_migration_region_init() and then pass the object. The conditional branch to handle obj is strange here too, it's fatal if vfio_migration_region_init() doesn't find an object, why do we handle it as optional here? Also, what is this doing? Comments would be nice... Thanks, Alex > + pstrcat(id, sizeof(id), "vfio"); > + > + register_savevm_live(id, VMSTATE_INSTANCE_ID_ANY, 1, &savevm_vfio_handlers, > + vbasedev); > vbasedev->vm_state = qemu_add_vm_change_state_handler(vfio_vmstate_change, > vbasedev); > vbasedev->migration_state.notify = vfio_migration_state_notifier; > diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events > index bcb3fa7314d7..982d8dccb219 100644 > --- a/hw/vfio/trace-events > +++ b/hw/vfio/trace-events > @@ -152,3 +152,5 @@ vfio_migration_probe(const char *name, uint32_t index) " (%s) Region %d" > vfio_migration_set_state(const char *name, uint32_t state) " (%s) state %d" > vfio_vmstate_change(const char *name, int running, const char *reason, uint32_t dev_state) " (%s) running %d reason %s device state %d" > vfio_migration_state_notifier(const char *name, const char *state) " (%s) state %s" > +vfio_save_setup(const char *name) " (%s)" > +vfio_save_cleanup(const char *name) " (%s)"