Re: [PATCH v3 08/21] migration: Make multifd_load_setup() get an Error parameter

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Juan Quintela (quintela@redhat.com) wrote:
> We need to change the full chain to pass the Error parameter.
> 
> Signed-off-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> 
> ---
> 
> Always use a local_err, and in case of error propagate/print it as needed.
> ---
>  migration/migration.c | 35 +++++++++++++++++++++++++++++------
>  migration/migration.h |  2 +-
>  migration/ram.c       |  2 +-
>  migration/ram.h       |  2 +-
>  migration/rdma.c      |  2 +-
>  5 files changed, 33 insertions(+), 10 deletions(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index 7140d1e040..ef17b9f3f2 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -518,13 +518,23 @@ fail:
>      exit(EXIT_FAILURE);
>  }
>  
> -static void migration_incoming_setup(QEMUFile *f)
> +/**
> + * @migration_incoming_setup: Setup incoming migration
> + *
> + * Returns 0 for no error or 1 for error
> + *
> + * @f: file for main migration channel
> + * @errp: where to put errors
> + */
> +static int migration_incoming_setup(QEMUFile *f, Error **errp)
>  {
>      MigrationIncomingState *mis = migration_incoming_get_current();
> +    Error *local_err = NULL;
>  
> -    if (multifd_load_setup() != 0) {
> +    if (multifd_load_setup(&local_err) != 0) {
>          /* We haven't been able to create multifd threads
>             nothing better to do */
> +        error_report_err(local_err);
>          exit(EXIT_FAILURE);
>      }
>  
> @@ -532,6 +542,7 @@ static void migration_incoming_setup(QEMUFile *f)
>          mis->from_src_file = f;
>      }
>      qemu_file_set_blocking(f, false);
> +    return 0;
>  }
>  
>  void migration_incoming_process(void)
> @@ -572,19 +583,27 @@ static bool postcopy_try_recover(QEMUFile *f)
>      return false;
>  }
>  
> -void migration_fd_process_incoming(QEMUFile *f)
> +void migration_fd_process_incoming(QEMUFile *f, Error **errp)
>  {
> +    Error *local_err = NULL;
> +
>      if (postcopy_try_recover(f)) {
>          return;
>      }
>  
> -    migration_incoming_setup(f);
> +    if (migration_incoming_setup(f, &local_err)) {
> +        if (local_err) {
> +            error_propagate(errp, local_err);
> +        }
> +        return;
> +    }
>      migration_incoming_process();
>  }
>  
>  void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
>  {
>      MigrationIncomingState *mis = migration_incoming_get_current();
> +    Error *local_err = NULL;
>      bool start_migration;
>  
>      if (!mis->from_src_file) {
> @@ -596,7 +615,12 @@ void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
>              return;
>          }
>  
> -        migration_incoming_setup(f);
> +        if (migration_incoming_setup(f, &local_err)) {
> +            if (local_err) {
> +                error_propagate(errp, local_err);
> +            }
> +            return;
> +        }
>  
>          /*
>           * Common migration only needs one channel, so we can start
> @@ -604,7 +628,6 @@ void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
>           */
>          start_migration = !migrate_use_multifd();
>      } else {
> -        Error *local_err = NULL;
>          /* Multiple connections */
>          assert(migrate_use_multifd());
>          start_migration = multifd_recv_new_channel(ioc, &local_err);
> diff --git a/migration/migration.h b/migration/migration.h
> index 44b1d56929..8473ddfc88 100644
> --- a/migration/migration.h
> +++ b/migration/migration.h
> @@ -265,7 +265,7 @@ struct MigrationState
>  
>  void migrate_set_state(int *state, int old_state, int new_state);
>  
> -void migration_fd_process_incoming(QEMUFile *f);
> +void migration_fd_process_incoming(QEMUFile *f, Error **errp);
>  void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp);
>  void migration_incoming_process(void);
>  
> diff --git a/migration/ram.c b/migration/ram.c
> index d537264ba5..125c6d0f60 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -1463,7 +1463,7 @@ static void *multifd_recv_thread(void *opaque)
>      return NULL;
>  }
>  
> -int multifd_load_setup(void)
> +int multifd_load_setup(Error **errp)
>  {
>      int thread_count;
>      uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
> diff --git a/migration/ram.h b/migration/ram.h
> index da22a417ea..42be471d52 100644
> --- a/migration/ram.h
> +++ b/migration/ram.h
> @@ -43,7 +43,7 @@ uint64_t ram_bytes_total(void);
>  
>  int multifd_save_setup(Error **errp);
>  void multifd_save_cleanup(void);
> -int multifd_load_setup(void);
> +int multifd_load_setup(Error **errp);
>  int multifd_load_cleanup(Error **errp);
>  bool multifd_recv_all_channels_created(void);
>  bool multifd_recv_new_channel(QIOChannel *ioc, Error **errp);
> diff --git a/migration/rdma.c b/migration/rdma.c
> index e241dcb992..2379b8345b 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -4004,7 +4004,7 @@ static void rdma_accept_incoming_migration(void *opaque)
>      }
>  
>      rdma->migration_started_on_destination = 1;
> -    migration_fd_process_incoming(f);
> +    migration_fd_process_incoming(f, errp);
>  }
>  
>  void rdma_start_incoming_migration(const char *host_port, Error **errp)
> -- 
> 2.24.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK