Commit b3f7f0c5 authored by zhanghailiang's avatar zhanghailiang Committed by Amit Shah
Browse files

COLO: Implement the process of failover for primary VM 



For primary side, if COLO gets failover request from users.
To be exact, gets 'x_colo_lost_heartbeat' command.
COLO thread will exit the loop while the failover BH does the
cleanup work and resumes VM.

Signed-off-by: default avatarzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: default avatarLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: default avatarAmit Shah <amit.shah@redhat.com>
Signed-off-by: default avatarAmit Shah <amit@amitshah.net>
parent aef06085

include/migration/colo.h

+3 −0
Original line number Diff line number Diff line
@@ -32,4 +32,7 @@ void *colo_process_incoming_thread(void *opaque); 
bool migration_incoming_in_colo_state(void);



COLOMode get_colo_mode(void);



/* failover */

void colo_do_failover(MigrationState *s);

#endif

include/migration/failover.h

+1 −0
Original line number Diff line number Diff line
@@ -21,5 +21,6 @@ FailoverStatus failover_set_state(FailoverStatus old_state, 
                                     FailoverStatus new_state);

FailoverStatus failover_get_state(void);

void failover_request_active(Error **errp);

bool failover_request_is_active(void);



#endif

migration/colo-failover.c

+1 −1
Original line number Diff line number Diff line
@@ -36,7 +36,7 @@ static void colo_failover_bh(void *opaque) 
        return;

    }



    /* TODO: Do failover work */

    colo_do_failover(NULL);

}



void failover_request_active(Error **errp)

migration/colo.c

+50 −0
Original line number Diff line number Diff line
@@ -41,6 +41,40 @@ bool migration_incoming_in_colo_state(void) 
    return mis && (mis->state == MIGRATION_STATUS_COLO);

}



static bool colo_runstate_is_stopped(void)

{

    return runstate_check(RUN_STATE_COLO) || !runstate_is_running();

}



static void primary_vm_do_failover(void)

{

    MigrationState *s = migrate_get_current();

    int old_state;



    migrate_set_state(&s->state, MIGRATION_STATUS_COLO,

                      MIGRATION_STATUS_COMPLETED);



    old_state = failover_set_state(FAILOVER_STATUS_ACTIVE,

                                   FAILOVER_STATUS_COMPLETED);

    if (old_state != FAILOVER_STATUS_ACTIVE) {

        error_report("Incorrect state (%s) while doing failover for Primary VM",

                     FailoverStatus_lookup[old_state]);

        return;

    }

}



void colo_do_failover(MigrationState *s)

{

    /* Make sure VM stopped while failover happened. */

    if (!colo_runstate_is_stopped()) {

        vm_stop_force_state(RUN_STATE_COLO);

    }



    if (get_colo_mode() == COLO_MODE_PRIMARY) {

        primary_vm_do_failover();

    }

}



static void colo_send_message(QEMUFile *f, COLOMessage msg,

                              Error **errp)

{
@@ -162,9 +196,20 @@ static int colo_do_checkpoint_transaction(MigrationState *s, 
    bioc->usage = 0;



    qemu_mutex_lock_iothread();

    if (failover_get_state() != FAILOVER_STATUS_NONE) {

        qemu_mutex_unlock_iothread();

        goto out;

    }

    vm_stop_force_state(RUN_STATE_COLO);

    qemu_mutex_unlock_iothread();

    trace_colo_vm_state_change("run", "stop");

    /*

     * Failover request bh could be called after vm_stop_force_state(),

     * So we need check failover_request_is_active() again.

     */

    if (failover_get_state() != FAILOVER_STATUS_NONE) {

        goto out;

    }



    /* Disable block migration */

    s->params.blk = 0;
@@ -259,6 +304,11 @@ static void colo_process_checkpoint(MigrationState *s) 
    trace_colo_vm_state_change("stop", "run");



    while (s->state == MIGRATION_STATUS_COLO) {

        if (failover_get_state() != FAILOVER_STATUS_NONE) {

            error_report("failover request");

            goto out;

        }



        current_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);

        if (current_time - checkpoint_time <

            s->parameters.x_checkpoint_delay) {