multifd: Make multifd_save_setup() get an Error parameter

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

migration/migration.c

@@ -3367,6 +3367,7 @@ static void *migration_thread(void *opaque)
 
 void migrate_fd_connect(MigrationState *s, Error *error_in)
 {
+    Error *local_err = NULL;
     int64_t rate_limit;
     bool resume = s->state == MIGRATION_STATUS_POSTCOPY_PAUSED;
 
@@ -3415,7 +3416,8 @@ void migrate_fd_connect(MigrationState *s, Error *error_in)
         return;
     }
 
-    if (multifd_save_setup() != 0) {
+    if (multifd_save_setup(&local_err) != 0) {
+        error_report_err(local_err);
         migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
                           MIGRATION_STATUS_FAILED);
         migrate_fd_cleanup(s);

migration/ram.c

@@ -1252,7 +1252,7 @@ static void multifd_new_send_channel_async(QIOTask *task, gpointer opaque)
     }
 }
 
-int multifd_save_setup(void)
+int multifd_save_setup(Error **errp)
 {
     int thread_count;
     uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();

migration/ram.h

@@ -41,7 +41,7 @@ int xbzrle_cache_resize(int64_t new_size, Error **errp);
 uint64_t ram_bytes_remaining(void);
 uint64_t ram_bytes_total(void);
 
-int multifd_save_setup(void);
+int multifd_save_setup(Error **errp);
 void multifd_save_cleanup(void);
 int multifd_load_setup(void);
 int multifd_load_cleanup(Error **errp);