Re: [PATCH 3/5] migration: Introduce migration_ioc_[un]register_yank()

[Dr. David Alan Gilbert]

* Peter Xu (peterx@redhat.com) wrote:
> There're plenty of places in migration/* that checks against either socket or
> tls typed ioc for yank operations.  Provide two helpers to hide all these
> information.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>

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

> ---
>  migration/channel.c           | 15 ++-------------
>  migration/multifd.c           |  8 ++------
>  migration/qemu-file-channel.c |  8 ++------
>  migration/yank_functions.c    | 28 ++++++++++++++++++++++++++++
>  migration/yank_functions.h    |  2 ++
>  5 files changed, 36 insertions(+), 25 deletions(-)
> 
> diff --git a/migration/channel.c b/migration/channel.c
> index 01275a9162..c4fc000a1a 100644
> --- a/migration/channel.c
> +++ b/migration/channel.c
> @@ -44,13 +44,7 @@ void migration_channel_process_incoming(QIOChannel *ioc)
>                               TYPE_QIO_CHANNEL_TLS)) {
>          migration_tls_channel_process_incoming(s, ioc, &local_err);
>      } else {
> -        if (object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_SOCKET) ||
> -            object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_TLS)) {
> -            yank_register_function(MIGRATION_YANK_INSTANCE,
> -                                   migration_yank_iochannel,
> -                                   QIO_CHANNEL(ioc));
> -        }
> -
> +        migration_ioc_register_yank(ioc);
>          migration_ioc_process_incoming(ioc, &local_err);
>      }
>  
> @@ -94,12 +88,7 @@ void migration_channel_connect(MigrationState *s,
>          } else {
>              QEMUFile *f = qemu_fopen_channel_output(ioc);
>  
> -            if (object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_SOCKET) ||
> -                object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_TLS)) {
> -                yank_register_function(MIGRATION_YANK_INSTANCE,
> -                                       migration_yank_iochannel,
> -                                       QIO_CHANNEL(ioc));
> -            }
> +            migration_ioc_register_yank(ioc);
>  
>              qemu_mutex_lock(&s->qemu_file_lock);
>              s->to_dst_file = f;
> diff --git a/migration/multifd.c b/migration/multifd.c
> index ab41590e71..377da78f5b 100644
> --- a/migration/multifd.c
> +++ b/migration/multifd.c
> @@ -987,12 +987,8 @@ int multifd_load_cleanup(Error **errp)
>      for (i = 0; i < migrate_multifd_channels(); i++) {
>          MultiFDRecvParams *p = &multifd_recv_state->params[i];
>  
> -        if ((object_dynamic_cast(OBJECT(p->c), TYPE_QIO_CHANNEL_SOCKET) ||
> -             object_dynamic_cast(OBJECT(p->c), TYPE_QIO_CHANNEL_TLS))
> -            && OBJECT(p->c)->ref == 1) {
> -            yank_unregister_function(MIGRATION_YANK_INSTANCE,
> -                                     migration_yank_iochannel,
> -                                     QIO_CHANNEL(p->c));
> +        if (OBJECT(p->c)->ref == 1) {
> +            migration_ioc_unregister_yank(p->c);
>          }
>  
>          object_unref(OBJECT(p->c));
> diff --git a/migration/qemu-file-channel.c b/migration/qemu-file-channel.c
> index fad340ea7a..867a5ed0c3 100644
> --- a/migration/qemu-file-channel.c
> +++ b/migration/qemu-file-channel.c
> @@ -107,12 +107,8 @@ static int channel_close(void *opaque, Error **errp)
>      int ret;
>      QIOChannel *ioc = QIO_CHANNEL(opaque);
>      ret = qio_channel_close(ioc, errp);
> -    if ((object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_SOCKET) ||
> -         object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_TLS))
> -        && OBJECT(ioc)->ref == 1) {
> -        yank_unregister_function(MIGRATION_YANK_INSTANCE,
> -                                 migration_yank_iochannel,
> -                                 QIO_CHANNEL(ioc));
> +    if (OBJECT(ioc)->ref == 1) {
> +        migration_ioc_unregister_yank(ioc);
>      }
>      object_unref(OBJECT(ioc));
>      return ret;
> diff --git a/migration/yank_functions.c b/migration/yank_functions.c
> index 96c90e17dc..23697173ae 100644
> --- a/migration/yank_functions.c
> +++ b/migration/yank_functions.c
> @@ -11,6 +11,9 @@
>  #include "qapi/error.h"
>  #include "io/channel.h"
>  #include "yank_functions.h"
> +#include "qemu/yank.h"
> +#include "io/channel-socket.h"
> +#include "io/channel-tls.h"
>  
>  void migration_yank_iochannel(void *opaque)
>  {
> @@ -18,3 +21,28 @@ void migration_yank_iochannel(void *opaque)
>  
>      qio_channel_shutdown(ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
>  }
> +
> +/* Return whether yank is supported on this ioc */
> +static bool migration_ioc_yank_supported(QIOChannel *ioc)
> +{
> +    return object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_SOCKET) ||
> +        object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_TLS);
> +}
> +
> +void migration_ioc_register_yank(QIOChannel *ioc)
> +{
> +    if (migration_ioc_yank_supported(ioc)) {
> +        yank_register_function(MIGRATION_YANK_INSTANCE,
> +                               migration_yank_iochannel,
> +                               QIO_CHANNEL(ioc));
> +    }
> +}
> +
> +void migration_ioc_unregister_yank(QIOChannel *ioc)
> +{
> +    if (migration_ioc_yank_supported(ioc)) {
> +        yank_unregister_function(MIGRATION_YANK_INSTANCE,
> +                                 migration_yank_iochannel,
> +                                 QIO_CHANNEL(ioc));
> +    }
> +}
> diff --git a/migration/yank_functions.h b/migration/yank_functions.h
> index 055ea22523..74c7f18c91 100644
> --- a/migration/yank_functions.h
> +++ b/migration/yank_functions.h
> @@ -15,3 +15,5 @@
>   * @opaque: QIOChannel to shutdown
>   */
>  void migration_yank_iochannel(void *opaque);
> +void migration_ioc_register_yank(QIOChannel *ioc);
> +void migration_ioc_unregister_yank(QIOChannel *ioc);
> -- 
> 2.31.1
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK