Re: [libvirt] [PATCH 04/10] qemu: Recover from interrupted migration
On 07/18/2011 06:27 PM, Jiri Denemark wrote:
---
src/qemu/qemu_process.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 109 insertions(+), 1 deletions(-)
static int
+qemuProcessRecoverMigration(struct qemud_driver *driver,
+ virDomainObjPtr vm,
+ virConnectPtr conn,
+ enum qemuDomainAsyncJob job,
+ enum qemuMigrationJobPhase phase,
+ virDomainState state,
+ int reason)
+{
+ if (job == QEMU_ASYNC_JOB_MIGRATION_IN) {
+ switch (phase) {
+ case QEMU_MIGRATION_PHASE_NONE:
+ case QEMU_MIGRATION_PHASE_PERFORM2:
+ case QEMU_MIGRATION_PHASE_BEGIN3:
Should we reject as impossible the phases that should never be
encountered on MIGRATION_IN? For example, QEMU_MIGRATION_PHASE_BEGIN3
belongs to MIGRATION_OUT, so if our job is MIGRATION_IN but we see that
phase, we should probably fail rather than return 0.
+ case QEMU_MIGRATION_PHASE_PERFORM2:
+ case QEMU_MIGRATION_PHASE_PERFORM3:
+ /* migration is still in progress, let's cancel it and resume the
+ * domain */
+ VIR_DEBUG("Canceling unfinished outgoing migration of domain %s",
+ vm->def->name);
+ /* TODO cancel possibly running migrate operation */
As in issue qemuMonitorMigrateCancel, but ignoring if it fails? Might
be reasonable, but probably as a separate patch.
+ /* resume the domain but only if it was paused as a
result of
+ * migration */
+ if (state == VIR_DOMAIN_PAUSED&&
+ (reason == VIR_DOMAIN_PAUSED_MIGRATION ||
+ reason == VIR_DOMAIN_PAUSED_UNKNOWN)) {
+ if (qemuProcessStartCPUs(driver, vm, conn,
+ VIR_DOMAIN_RUNNING_UNPAUSED)< 0) {
On the other hand, will the monitor command to restart cpus even work if
a pending migration is underway? So we may have to do the
qemuMonitorMigrateCancel no matter what, to ensure the monitor will let
us resume.
I think what you have works (strict improvement over what we have now),
even if it can be further improved with later patches, so:
ACK.
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library http://libvirt.org