On 21/07/2023 15:09, Cédric Le Goater wrote:
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On 7/16/23 10:15, 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 <avih...@nvidia.com>
Signed-off-by: Joao Martins <joao.m.mart...@oracle.com>
---
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..753b320739 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_should_block_multiple_devices_migration(void)
Could we revert the logic and call the routine :
vfio_multiple_devices_migration_is_supported()
I think it would be clearer in the callers. This is minor.
Yes, of course, I will change that.
Thanks!
{
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_should_block_multiple_devices_migration()) {
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_should_block_multiple_devices_migration()) {
return;
}
