Re: [PATCH v4 02/18] migration/rdma: judge whether or not the RDMA is used for migration

[Dr. David Alan Gilbert]

* Chuan Zheng (zhengchuan@huawei.com) wrote:
> Add enabled_rdma_migration into MigrationState to judge
> whether or not the RDMA is used for migration.
> 
> Signed-off-by: Zhimin Feng <fengzhimin1@huawei.com>
> Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>

I'd rather see a separate flag added to each of the MigrationState and
MigrationIncomingState separately for outoging and incoming migration.

It's also probably better to call it 'is_rdma_migration' rather than
enabled.

Dave

> ---
>  migration/migration.c | 13 +++++++++++++
>  migration/migration.h |  6 ++++++
>  2 files changed, 19 insertions(+)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index 447dfb9..129c81a 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -418,11 +418,13 @@ void migrate_add_address(SocketAddress *address)
>  static void qemu_start_incoming_migration(const char *uri, Error **errp)
>  {
>      const char *p = NULL;
> +    MigrationState *s = migrate_get_current();
>  
>      if (!yank_register_instance(MIGRATION_YANK_INSTANCE, errp)) {
>          return;
>      }
>  
> +    s->enabled_rdma_migration = false;
>      qapi_event_send_migration(MIGRATION_STATUS_SETUP);
>      if (strstart(uri, "tcp:", &p) ||
>          strstart(uri, "unix:", NULL) ||
> @@ -430,6 +432,7 @@ static void qemu_start_incoming_migration(const char 
> *uri, Error **errp)
>          socket_start_incoming_migration(p ? p : uri, errp);
>  #ifdef CONFIG_RDMA
>      } else if (strstart(uri, "rdma:", &p)) {
> +        s->enabled_rdma_migration = true;
>          rdma_start_incoming_migration(p, errp);
>  #endif
>      } else if (strstart(uri, "exec:", &p)) {
> @@ -1921,6 +1924,7 @@ void migrate_init(MigrationState *s)
>      s->start_postcopy = false;
>      s->postcopy_after_devices = false;
>      s->migration_thread_running = false;
> +    s->enabled_rdma_migration = false;
>      error_free(s->error);
>      s->error = NULL;
>      s->hostname = NULL;
> @@ -2162,6 +2166,7 @@ void qmp_migrate(const char *uri, bool has_blk, bool 
> blk,
>          socket_start_outgoing_migration(s, p ? p : uri, &local_err);
>  #ifdef CONFIG_RDMA
>      } else if (strstart(uri, "rdma:", &p)) {
> +        s->enabled_rdma_migration = true;
>          rdma_start_outgoing_migration(s, p, &local_err);
>  #endif
>      } else if (strstart(uri, "exec:", &p)) {
> @@ -2391,6 +2396,14 @@ bool migrate_rdma_pin_all(void)
>      return s->enabled_capabilities[MIGRATION_CAPABILITY_RDMA_PIN_ALL];
>  }
>  
> +bool migrate_use_rdma(void)
> +{
> +    MigrationState *s;
> +    s = migrate_get_current();
> +
> +    return s->enabled_rdma_migration;
> +}
> +
>  bool migrate_use_multifd(void)
>  {
>      MigrationState *s;
> diff --git a/migration/migration.h b/migration/migration.h
> index 22b36f3..da5681b 100644
> --- a/migration/migration.h
> +++ b/migration/migration.h
> @@ -280,6 +280,11 @@ struct MigrationState {
>       * This save hostname when out-going migration starts
>       */
>      char *hostname;
> +
> +    /*
> +     * Enable RDMA migration
> +     */
> +    bool enabled_rdma_migration;
>  };
>  
>  void migrate_set_state(int *state, int old_state, int new_state);
> @@ -317,6 +322,7 @@ bool migrate_validate_uuid(void);
>  
>  bool migrate_auto_converge(void);
>  bool migrate_rdma_pin_all(void);
> +bool migrate_use_rdma(void);
>  bool migrate_use_multifd(void);
>  bool migrate_pause_before_switchover(void);
>  int migrate_multifd_channels(void);
> -- 
> 1.8.3.1
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK