Commit a3ec6b7d authored by Ivan Ren's avatar Ivan Ren Committed by Juan Quintela
Browse files

migration: fix migrate_cancel leads live_migration thread hung forever 



When we 'migrate_cancel' a multifd migration, live_migration thread may
hung forever at some points, because of multifd_send_thread has already
exit for socket error:
1. multifd_send_pages may hung at qemu_sem_wait(&multifd_send_state->
   channels_ready)
2. multifd_send_sync_main my hung at qemu_sem_wait(&multifd_send_state->
   sem_sync)

Signed-off-by: default avatarIvan Ren <ivanren@tencent.com>
Message-Id: <1561468699-9819-3-git-send-email-ivanren@tencent.com>
Reviewed-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: default avatarJuan Quintela <quintela@redhat.com>
Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>

---

Remove spurious not needed bits
parent 713f762a

migration/ram.c

+14 −2
Original line number Diff line number Diff line
@@ -1097,7 +1097,8 @@ static void *multifd_send_thread(void *opaque) 
{

    MultiFDSendParams *p = opaque;

    Error *local_err = NULL;

    int ret;

    int ret = 0;

    uint32_t flags = 0;



    trace_multifd_send_thread_start(p->id);

    rcu_register_thread();
@@ -1115,7 +1116,7 @@ static void *multifd_send_thread(void *opaque) 
        if (p->pending_job) {

            uint32_t used = p->pages->used;

            uint64_t packet_num = p->packet_num;

            uint32_t flags = p->flags;

            flags = p->flags;



            p->next_packet_size = used * qemu_target_page_size();

            multifd_send_fill_packet(p);
@@ -1164,6 +1165,17 @@ out: 
        multifd_send_terminate_threads(local_err);

    }



    /*

     * Error happen, I will exit, but I can't just leave, tell

     * who pay attention to me.

     */

    if (ret != 0) {

        if (flags & MULTIFD_FLAG_SYNC) {

            qemu_sem_post(&multifd_send_state->sem_sync);

        }

        qemu_sem_post(&multifd_send_state->channels_ready);

    }



    qemu_mutex_lock(&p->mutex);

    p->running = false;

    qemu_mutex_unlock(&p->mutex);