From: Peter Xu <pet...@redhat.com> Do one shot cpu sync at qemu_savevm_state_complete_precopy_non_iterable(), instead of coding it separately in two places.
Note that in the context of qemu_savevm_state_complete_precopy(), this patch is also an optimization for postcopy path, in that we can avoid sync cpu twice during switchover: before this patch, postcopy_start() invokes twice on qemu_savevm_state_complete_precopy(), each of them will try to sync CPU info. In reality, only one of them would be enough. For background snapshot, there's no intended functional change. Signed-off-by: Peter Xu <pet...@redhat.com> Tested-by: Jiri Denemark <jdene...@redhat.com> Reviewed-by: Juraj Marcin <jmar...@redhat.com> Link: https://lore.kernel.org/r/20250114230746.3268797-7-pet...@redhat.com Signed-off-by: Fabiano Rosas <faro...@suse.de> --- migration/migration.c | 6 +----- migration/savevm.c | 5 +++-- 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index d8a6bc12e0..46e30a4814 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -3749,11 +3749,7 @@ static void *bg_migration_thread(void *opaque) if (migration_stop_vm(s, RUN_STATE_PAUSED)) { goto fail; } - /* - * Put vCPUs in sync with shadow context structures, then - * save their state to channel-buffer along with devices. - */ - cpu_synchronize_all_states(); + if (qemu_savevm_state_complete_precopy_non_iterable(fb, false)) { goto fail; } diff --git a/migration/savevm.c b/migration/savevm.c index 5e56a5d9fc..92e77ca92b 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1531,6 +1531,9 @@ int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f, Error *local_err = NULL; int ret; + /* Making sure cpu states are synchronized before saving non-iterable */ + cpu_synchronize_all_states(); + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { if (se->vmsd && se->vmsd->early_setup) { /* Already saved during qemu_savevm_state_setup(). */ @@ -1584,8 +1587,6 @@ int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) trace_savevm_state_complete_precopy(); - cpu_synchronize_all_states(); - if (!in_postcopy || iterable_only) { ret = qemu_savevm_state_complete_precopy_iterable(f, in_postcopy); if (ret) { -- 2.35.3
