Re: [Qemu-devel] [PATCH RFC v2 4/5] migration: remove unused &local_err parameter in multifd_save_cleanup

[Philippe Mathieu-Daudé]

On 29/11/18 11:03, Fei Li wrote:
> Always call migrate_set_error() to set the error state without relying
> on whether multifd_save_cleanup() succeeds.  As the passed &local_err
> is never used in multifd_save_cleanup(), remove it. And make the
> function be: void multifd_save_cleanup(void).

Reading this after your patch 1/5, maybe multifd_save_cleanup() lacks
error reporting on failure. So the actual prototype is correct, we just
need to use **errp in that function (like reporting invalid thread
instead of calling qemu_thread_join()).

> 
> Signed-off-by: Fei Li <address@hidden>
> Reviewed-by: Juan Quintela <address@hidden>
> ---
>  migration/migration.c |  5 +----
>  migration/ram.c       | 11 ++++-------
>  migration/ram.h       |  2 +-
>  3 files changed, 6 insertions(+), 12 deletions(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index 72106bddf0..0537fc0c26 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -1386,7 +1386,6 @@ static void migrate_fd_cleanup(void *opaque)
>      qemu_savevm_state_cleanup();
>  
>      if (s->to_dst_file) {
> -        Error *local_err = NULL;
>          QEMUFile *tmp;
>  
>          trace_migrate_fd_cleanup();
> @@ -1397,9 +1396,7 @@ static void migrate_fd_cleanup(void *opaque)
>          }
>          qemu_mutex_lock_iothread();
>  
> -        if (multifd_save_cleanup(&local_err) != 0) {
> -            error_report_err(local_err);
> -        }
> +        multifd_save_cleanup();
>          qemu_mutex_lock(&s->qemu_file_lock);
>          tmp = s->to_dst_file;
>          s->to_dst_file = NULL;
> diff --git a/migration/ram.c b/migration/ram.c
> index e13b9349d0..c44cb6f56d 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -917,13 +917,12 @@ static void multifd_send_terminate_threads(Error *err)
>      }
>  }
>  
> -int multifd_save_cleanup(Error **errp)
> +void multifd_save_cleanup(void)
>  {
>      int i;
> -    int ret = 0;
>  
>      if (!migrate_use_multifd()) {
> -        return 0;
> +        return;
>      }
>      multifd_send_terminate_threads(NULL);
>      for (i = 0; i < migrate_multifd_channels(); i++) {
> @@ -953,7 +952,6 @@ int multifd_save_cleanup(Error **errp)
>      multifd_send_state->pages = NULL;
>      g_free(multifd_send_state);
>      multifd_send_state = NULL;
> -    return ret;
>  }
>  
>  static void multifd_send_sync_main(void)
> @@ -1071,9 +1069,8 @@ static void multifd_new_send_channel_async(QIOTask 
> *task, gpointer opaque)
>      Error *local_err = NULL;
>  
>      if (qio_task_propagate_error(task, &local_err)) {
> -        if (multifd_save_cleanup(&local_err) != 0) {
> -            migrate_set_error(migrate_get_current(), local_err);
> -        }
> +        migrate_set_error(migrate_get_current(), local_err);
> +        multifd_save_cleanup();
>      } else {
>          p->c = QIO_CHANNEL(sioc);
>          qio_channel_set_delay(p->c, false);
> diff --git a/migration/ram.h b/migration/ram.h
> index 046d3074be..936177b3e9 100644
> --- a/migration/ram.h
> +++ b/migration/ram.h
> @@ -43,7 +43,7 @@ uint64_t ram_bytes_remaining(void);
>  uint64_t ram_bytes_total(void);
>  
>  int multifd_save_setup(void);
> -int multifd_save_cleanup(Error **errp);
> +void multifd_save_cleanup(void);
>  int multifd_load_setup(void);
>  int multifd_load_cleanup(Error **errp);
>  bool multifd_recv_all_channels_created(void);
>