Commit 18cdcea3 authored by Juan Quintela's avatar Juan Quintela Committed by Dr. David Alan Gilbert
Browse files

migration: Make global sem_sync semaphore by channel 



This makes easy to debug things because when you want for all threads
to arrive at that semaphore, you know which one your are waiting for.

Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
Message-Id: <20190814020218.1868-3-quintela@redhat.com>
Reviewed-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
parent 5558c91a

migration/ram.c

+7 −7
Original line number Diff line number Diff line
@@ -661,6 +661,8 @@ typedef struct { 
    uint64_t num_packets;

    /* pages sent through this channel */

    uint64_t num_pages;

    /* syncs main thread and channels */

    QemuSemaphore sem_sync;

}  MultiFDSendParams;



typedef struct {
@@ -896,8 +898,6 @@ struct { 
    MultiFDSendParams *params;

    /* array of pages to sent */

    MultiFDPages_t *pages;

    /* syncs main thread and channels */

    QemuSemaphore sem_sync;

    /* global number of generated multifd packets */

    uint64_t packet_num;

    /* send channels ready */
@@ -1039,6 +1039,7 @@ void multifd_save_cleanup(void) 
        p->c = NULL;

        qemu_mutex_destroy(&p->mutex);

        qemu_sem_destroy(&p->sem);

        qemu_sem_destroy(&p->sem_sync);

        g_free(p->name);

        p->name = NULL;

        multifd_pages_clear(p->pages);
@@ -1048,7 +1049,6 @@ void multifd_save_cleanup(void) 
        p->packet = NULL;

    }

    qemu_sem_destroy(&multifd_send_state->channels_ready);

    qemu_sem_destroy(&multifd_send_state->sem_sync);

    g_free(multifd_send_state->params);

    multifd_send_state->params = NULL;

    multifd_pages_clear(multifd_send_state->pages);
@@ -1096,7 +1096,7 @@ static void multifd_send_sync_main(RAMState *rs) 
        MultiFDSendParams *p = &multifd_send_state->params[i];



        trace_multifd_send_sync_main_wait(p->id);

        qemu_sem_wait(&multifd_send_state->sem_sync);

        qemu_sem_wait(&p->sem_sync);

    }

    trace_multifd_send_sync_main(multifd_send_state->packet_num);

}
@@ -1156,7 +1156,7 @@ static void *multifd_send_thread(void *opaque) 
            qemu_mutex_unlock(&p->mutex);



            if (flags & MULTIFD_FLAG_SYNC) {

                qemu_sem_post(&multifd_send_state->sem_sync);

                qemu_sem_post(&p->sem_sync);

            }

            qemu_sem_post(&multifd_send_state->channels_ready);

        } else if (p->quit) {
@@ -1179,7 +1179,7 @@ out: 
     */

    if (ret != 0) {

        if (flags & MULTIFD_FLAG_SYNC) {

            qemu_sem_post(&multifd_send_state->sem_sync);

            qemu_sem_post(&p->sem_sync);

        }

        qemu_sem_post(&multifd_send_state->channels_ready);

    }
@@ -1225,7 +1225,6 @@ int multifd_save_setup(void) 
    multifd_send_state = g_malloc0(sizeof(*multifd_send_state));

    multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);

    multifd_send_state->pages = multifd_pages_init(page_count);

    qemu_sem_init(&multifd_send_state->sem_sync, 0);

    qemu_sem_init(&multifd_send_state->channels_ready, 0);



    for (i = 0; i < thread_count; i++) {
@@ -1233,6 +1232,7 @@ int multifd_save_setup(void) 


        qemu_mutex_init(&p->mutex);

        qemu_sem_init(&p->sem, 0);

        qemu_sem_init(&p->sem_sync, 0);

        p->quit = false;

        p->pending_job = 0;

        p->id = i;