* Juan Quintela (quint...@redhat.com) wrote: > Right now, there is no easy way to dectect if we have already > cancelled/finished/failed a migration. This field is setup to true > when we start a migration, and it is set to false as soon as we stop > it. > > It fixes a real bug, in ram_save_iterate() we call functions that > wrote to the channel even if we know that migration has stopped for > any reason. This gives problems with multifd because we need to > synchronize various semoaphores that we don't want to take. > > Signed-off-by: Juan Quintela <quint...@redhat.com>
Why can't you use migration_is_active() in the ram.c case? My preference would be just to stick with something derived from the state rather than tacking another state bit on. > --- > migration/migration.c | 5 +++++ > migration/migration.h | 5 +++++ > migration/ram.c | 2 +- > migration/savevm.c | 2 ++ > 4 files changed, 13 insertions(+), 1 deletion(-) > > diff --git a/migration/migration.c b/migration/migration.c > index 990bff00c0..60bc8710b6 100644 > --- a/migration/migration.c > +++ b/migration/migration.c > @@ -1583,6 +1583,8 @@ static void migrate_fd_cancel(MigrationState *s) > QEMUFile *f = migrate_get_current()->to_dst_file; > trace_migrate_fd_cancel(); > > + s->active = false; > + > if (s->rp_state.from_dst_file) { > /* shutdown the rp socket, so causing the rp thread to shutdown */ > qemu_file_shutdown(s->rp_state.from_dst_file); > @@ -2834,6 +2836,7 @@ static void migration_completion(MigrationState *s) > } > > if (!migrate_colo_enabled()) { > + s->active = false; > migrate_set_state(&s->state, current_active_state, > MIGRATION_STATUS_COMPLETED); You've not always got these two the same way around - i.e. do you change the state first or do you set the active state first? I think it needs to be consistent. > } > @@ -2859,6 +2862,7 @@ fail_invalidate: > } > > fail: > + s->active = false; > migrate_set_state(&s->state, current_active_state, > MIGRATION_STATUS_FAILED); > } > @@ -3289,6 +3293,7 @@ static void *migration_thread(void *opaque) > } > > qemu_savevm_state_setup(s->to_dst_file); > + s->active = true; > > if (qemu_savevm_nr_failover_devices()) { > migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, > diff --git a/migration/migration.h b/migration/migration.h > index aa9ff6f27b..e0386efe95 100644 > --- a/migration/migration.h > +++ b/migration/migration.h > @@ -169,6 +169,11 @@ struct MigrationState > > int state; > > + /* Is the migration channel still open. When migration finish, > + * gets an error or is cancelled this becomes false. > + */ > + > + bool active; > /* State related to return path */ > struct { > QEMUFile *from_dst_file; > diff --git a/migration/ram.c b/migration/ram.c > index 8f9f3bba5b..44ca56e1ea 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -3521,7 +3521,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) > ram_control_after_iterate(f, RAM_CONTROL_ROUND); > > out: > - if (ret >= 0) { > + if (ret >= 0 && migrate_get_current()->active) { > multifd_send_sync_main(rs); > qemu_put_be64(f, RAM_SAVE_FLAG_EOS); > qemu_fflush(f); > diff --git a/migration/savevm.c b/migration/savevm.c > index adfdca26ac..3efde5b3dd 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -1550,6 +1550,7 @@ static int qemu_savevm_state(QEMUFile *f, Error **errp) > qemu_mutex_unlock_iothread(); > qemu_savevm_state_header(f); > qemu_savevm_state_setup(f); > + ms->active = true; > qemu_mutex_lock_iothread(); > > while (qemu_file_get_error(f) == 0) { > @@ -1574,6 +1575,7 @@ static int qemu_savevm_state(QEMUFile *f, Error **errp) > status = MIGRATION_STATUS_COMPLETED; > } > migrate_set_state(&ms->state, MIGRATION_STATUS_SETUP, status); > + ms->active = false; > > /* f is outer parameter, it should not stay in global migration state > after > * this function finished */ > -- > 2.24.1 > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK