qapi: Add VFIO devices migration stats in Migration stats

Added amount of bytes transferred to the VM at destination by all VFIO
devices

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

hw/vfio/common.c

@@ -292,6 +292,25 @@ const MemoryRegionOps vfio_region_ops = {
  * Device state interfaces
  */
 
+bool vfio_mig_active(void)
+{
+    VFIOGroup *group;
+    VFIODevice *vbasedev;
+
+    if (QLIST_EMPTY(&vfio_group_list)) {
+        return false;
+    }
+
+    QLIST_FOREACH(group, &vfio_group_list, next) {
+        QLIST_FOREACH(vbasedev, &group->device_list, next) {
+            if (vbasedev->migration_blocker) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
 static bool vfio_devices_all_stopped_and_saving(VFIOContainer *container)
 {
     VFIOGroup *group;

hw/vfio/migration.c

@@ -45,6 +45,8 @@
 #define VFIO_MIG_FLAG_DEV_SETUP_STATE   (0xffffffffef100003ULL)
 #define VFIO_MIG_FLAG_DEV_DATA_STATE    (0xffffffffef100004ULL)
 
+static int64_t bytes_transferred;
+
 static inline int vfio_mig_access(VFIODevice *vbasedev, void *val, int count,
                                   off_t off, bool iswrite)
 {
@@ -255,6 +257,7 @@ static int vfio_save_buffer(QEMUFile *f, VFIODevice *vbasedev, uint64_t *size)
         *size = data_size;
     }
 
+    bytes_transferred += data_size;
     return ret;
 }
 
@@ -785,6 +788,7 @@ static void vfio_migration_state_notifier(Notifier *notifier, void *data)
     case MIGRATION_STATUS_CANCELLING:
     case MIGRATION_STATUS_CANCELLED:
     case MIGRATION_STATUS_FAILED:
+        bytes_transferred = 0;
         ret = vfio_migration_set_state(vbasedev,
                       ~(VFIO_DEVICE_STATE_SAVING | VFIO_DEVICE_STATE_RESUMING),
                       VFIO_DEVICE_STATE_RUNNING);
@@ -866,6 +870,11 @@ err:
 
 /* ---------------------------------------------------------------------- */
 
+int64_t vfio_mig_bytes_transferred(void)
+{
+    return bytes_transferred;
+}
+
 int vfio_migration_probe(VFIODevice *vbasedev, Error **errp)
 {
     VFIOContainer *container = vbasedev->group->container;

include/hw/vfio/vfio-common.h

@@ -203,6 +203,9 @@ extern const MemoryRegionOps vfio_region_ops;
 typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
 extern VFIOGroupList vfio_group_list;
 
+bool vfio_mig_active(void);
+int64_t vfio_mig_bytes_transferred(void);
+
 #ifdef CONFIG_LINUX
 int vfio_get_region_info(VFIODevice *vbasedev, int index,
                          struct vfio_region_info **info);

migration/migration.c

@@ -57,6 +57,10 @@
 #include "qemu/queue.h"
 #include "multifd.h"
 
+#ifdef CONFIG_VFIO
+#include "hw/vfio/vfio-common.h"
+#endif
+
 #define MAX_THROTTLE  (128 << 20)      /* Migration transfer speed throttling */
 
 /* Amount of time to allocate to each "chunk" of bandwidth-throttled
@@ -1037,6 +1041,17 @@ static void populate_disk_info(MigrationInfo *info)
     }
 }
 
+static void populate_vfio_info(MigrationInfo *info)
+{
+#ifdef CONFIG_VFIO
+    if (vfio_mig_active()) {
+        info->has_vfio = true;
+        info->vfio = g_malloc0(sizeof(*info->vfio));
+        info->vfio->transferred = vfio_mig_bytes_transferred();
+    }
+#endif
+}
+
 static void fill_source_migration_info(MigrationInfo *info)
 {
     MigrationState *s = migrate_get_current();
@@ -1061,6 +1076,7 @@ static void fill_source_migration_info(MigrationInfo *info)
         populate_time_info(info, s);
         populate_ram_info(info, s);
         populate_disk_info(info);
+        populate_vfio_info(info);
         break;
     case MIGRATION_STATUS_COLO:
         info->has_status = true;
@@ -1069,6 +1085,7 @@ static void fill_source_migration_info(MigrationInfo *info)
     case MIGRATION_STATUS_COMPLETED:
         populate_time_info(info, s);
         populate_ram_info(info, s);
+        populate_vfio_info(info);
         break;
     case MIGRATION_STATUS_FAILED:
         info->has_status = true;

monitor/hmp-cmds.c

@@ -357,6 +357,12 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
         }
         monitor_printf(mon, "]\n");
     }
+
+    if (info->has_vfio) {
+        monitor_printf(mon, "vfio device transferred: %" PRIu64 " kbytes\n",
+                       info->vfio->transferred >> 10);
+    }
+
     qapi_free_MigrationInfo(info);
 }
 

qapi/migration.json

@@ -147,6 +147,18 @@
             'active', 'postcopy-active', 'postcopy-paused',
             'postcopy-recover', 'completed', 'failed', 'colo',
             'pre-switchover', 'device', 'wait-unplug' ] }
+##
+# @VfioStats:
+#
+# Detailed VFIO devices migration statistics
+#
+# @transferred: amount of bytes transferred to the target VM by VFIO devices
+#
+# Since: 5.2
+#
+##
+{ 'struct': 'VfioStats',
+  'data': {'transferred': 'int' } }
 
 ##
 # @MigrationInfo:
@@ -208,11 +220,16 @@
 #
 # @socket-address: Only used for tcp, to know what the real port is (Since 4.0)
 #
+# @vfio: @VfioStats containing detailed VFIO devices migration statistics,
+#        only returned if VFIO device is present, migration is supported by all
+#        VFIO devices and status is 'active' or 'completed' (since 5.2)
+#
 # Since: 0.14.0
 ##
 { 'struct': 'MigrationInfo',
   'data': {'*status': 'MigrationStatus', '*ram': 'MigrationStats',
            '*disk': 'MigrationStats',
+           '*vfio': 'VfioStats',
            '*xbzrle-cache': 'XBZRLECacheStats',
            '*total-time': 'int',
            '*expected-downtime': 'int',