multifd: Implement yank for multifd send side

To: qemu-devel <[email protected]>
Cc: "Dr. David Alan Gilbert" <[email protected]>, Juan Quintela
 <[email protected]>, Peter Xu <[email protected]>, Leonardo Bras Soares
 Passos <[email protected]>
Date: Wed, 1 Sep 2021 17:58:57 +0200 (1 week, 15 hours, 17 minutes ago)

[[PGP Signed Part:No public key for 35AB0B289C5DB258 created at 2021-09-01T17:58:57+0200 using RSA]]
When introducing yank functionality in the migration code I forgot
to cover the multifd send side.

Signed-off-by: Lukas Straub <[email protected]>
Tested-by: Leonardo Bras <[email protected]>
Reviewed-by: Leonardo Bras <[email protected]>
Reviewed-by: Juan Quintela <[email protected]>
Signed-off-by: Juan Quintela <[email protected]>

Author: lukasstraub2

migration/multifd.c

@@ -546,6 +546,9 @@ void multifd_save_cleanup(void)
         MultiFDSendParams *p = &multifd_send_state->params[i];
         Error *local_err = NULL;
 
+        if (p->registered_yank) {
+            migration_ioc_unregister_yank(p->c);
+        }
         socket_send_channel_destroy(p->c);
         p->c = NULL;
         qemu_mutex_destroy(&p->mutex);
@@ -813,7 +816,8 @@ static bool multifd_channel_connect(MultiFDSendParams *p,
                 return false;
             }
         } else {
-            /* update for tls qio channel */
+            migration_ioc_register_yank(ioc);
+            p->registered_yank = true;
             p->c = ioc;
             qemu_thread_create(&p->thread, p->name, multifd_send_thread, p,
                                    QEMU_THREAD_JOINABLE);

migration/multifd.h

@@ -85,6 +85,8 @@ typedef struct {
     bool running;
     /* should this thread finish */
     bool quit;
+    /* is the yank function registered */
+    bool registered_yank;
     /* thread has work to do */
     int pending_job;
     /* array of pages to sent */