Commit 4d65a621 authored by Juan Quintela's avatar Juan Quintela
Browse files

migration: Make sure that we don't call write() in case of error 



If we are exiting due to an error/finish/.... Just don't try to even
touch the channel with one IO operation.

Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
Reviewed-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
parent b99784ef

migration/ram.c

+25 −0
Original line number Diff line number Diff line
@@ -900,6 +900,12 @@ struct { 
    uint64_t packet_num;

    /* send channels ready */

    QemuSemaphore channels_ready;

    /*

     * Have we already run terminate threads.  There is a race when it

     * happens that we got one error while we are exiting.

     * We will use atomic operations.  Only valid values are 0 and 1.

     */

    int exiting;

} *multifd_send_state;



/*
@@ -928,6 +934,10 @@ static int multifd_send_pages(RAMState *rs) 
    MultiFDPages_t *pages = multifd_send_state->pages;

    uint64_t transferred;



    if (atomic_read(&multifd_send_state->exiting)) {

        return -1;

    }



    qemu_sem_wait(&multifd_send_state->channels_ready);

    for (i = next_channel;; i = (i + 1) % migrate_multifd_channels()) {

        p = &multifd_send_state->params[i];
@@ -1009,6 +1019,16 @@ static void multifd_send_terminate_threads(Error *err) 
        }

    }



    /*

     * We don't want to exit each threads twice.  Depending on where

     * we get the error, or if there are two independent errors in two

     * threads at the same time, we can end calling this function

     * twice.

     */

    if (atomic_xchg(&multifd_send_state->exiting, 1)) {

        return;

    }



    for (i = 0; i < migrate_multifd_channels(); i++) {

        MultiFDSendParams *p = &multifd_send_state->params[i];
@@ -1118,6 +1138,10 @@ static void *multifd_send_thread(void *opaque) 


    while (true) {

        qemu_sem_wait(&p->sem);



        if (atomic_read(&multifd_send_state->exiting)) {

            break;

        }

        qemu_mutex_lock(&p->mutex);



        if (p->pending_job) {
@@ -1224,6 +1248,7 @@ int multifd_save_setup(void) 
    multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);

    multifd_send_state->pages = multifd_pages_init(page_count);

    qemu_sem_init(&multifd_send_state->channels_ready, 0);

    atomic_set(&multifd_send_state->exiting, 0);



    for (i = 0; i < thread_count; i++) {

        MultiFDSendParams *p = &multifd_send_state->params[i];