Re: [libvirt] [REBASE PATCH v2 8/9] qemu: Allow showing the dump progress for memory only dump

https://bugzilla.redhat.com/show_bug.cgi?id=916061 If the QEMU version running is new enough (based on the DUMP_COMPLETED event), then we can add a 'detach' boolean to the dump-guest-memory command in order to tell QEMU to run in a thread. This ensures that we don't lock out other commands while the potentially long running dump memory is completed. This allows the usage of a qemuDumpWaitForCompletion which will wait for the event while the qemuDomainGetJobInfoDumpStats can be used via qemuDomainGetJobInfo in order to query QEMU in order to determine how far along the job is. Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/qemu/qemu_driver.c | 48 ++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 44 insertions(+), 4 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index adf66228b..efb3652df 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -3758,6 +3758,34 @@ qemuDomainManagedSaveRemove(virDomainPtr dom, unsigned int flags) } +/** + * qemuDumpWaitForCompletion: + * @vm: domain object + * + * If the query dump capability exists, then it's possible to start a + * guest memory dump operation using a thread via a 'detach' qualifier + * to the dump guest memory command. This allows the async check if the + * dump is done. + * + * Returns 0 on success, -1 on failure + */ +static int +qemuDumpWaitForCompletion(virDomainObjPtr vm) +{ + qemuDomainObjPrivatePtr priv = vm->privateData; + + if (!priv->job.dumpCompletion) + return 0;

+ + VIR_DEBUG("Waiting for dump completion"); + while (!priv->job.dumpCompleted && !priv->job.abortJob) { + if (virDomainObjWait(vm) < 0) + return -1; + } + return 0; +} + + static int qemuDumpToFd(virQEMUDriverPtr driver, virDomainObjPtr vm, @@ -3766,6 +3794,7 @@ qemuDumpToFd(virQEMUDriverPtr driver, const char *dumpformat) { qemuDomainObjPrivatePtr priv = vm->privateData; + bool detach = false; int ret = -1; if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DUMP_GUEST_MEMORY)) { @@ -3774,10 +3803,13 @@ qemuDumpToFd(virQEMUDriverPtr driver, return -1; } + detach = virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DUMP_COMPLETED); + if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, fd) < 0) return -1; - VIR_FREE(priv->job.current); + if (!detach) + VIR_FREE(priv->job.current); priv->job.dump_memory_only = true; if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0) @@ -3792,15 +3824,23 @@ qemuDumpToFd(virQEMUDriverPtr driver, "for this QEMU binary"), dumpformat); ret = -1; + ignore_value(qemuDomainObjExitMonitor(driver, vm)); goto cleanup; } } - ret = qemuMonitorDumpToFd(priv->mon, fd, dumpformat, false); + ret = qemuMonitorDumpToFd(priv->mon, fd, dumpformat, detach); - cleanup: - ignore_value(qemuDomainObjExitMonitor(driver, vm)); + if (detach && ret == 0) + priv->job.dumpCompletion = true; + + if ((qemuDomainObjExitMonitor(driver, vm) < 0) || ret < 0) + goto cleanup; + + if (detach) + ret = qemuDumpWaitForCompletion(vm);

+ cleanup: return ret; }