> -----Original Message----- > From: Thanos Makatos <thanos.maka...@nutanix.com> > Sent: Friday, March 8, 2024 2:21 PM > To: devel@lists.libvirt.org > Cc: Michal Privoznik <mpriv...@redhat.com> > Subject: RE: join running core dump job > > > -----Original Message----- > > From: Thanos Makatos <thanos.maka...@nutanix.com> > > Sent: Monday, March 4, 2024 9:45 PM > > To: Thanos Makatos <thanos.maka...@nutanix.com>; > devel@lists.libvirt.org > > Subject: RE: join running core dump job > > > > > -----Original Message----- > > > From: Thanos Makatos <thanos.maka...@nutanix.com> > > > Sent: Monday, March 4, 2024 5:24 PM > > > To: devel@lists.libvirt.org > > > Subject: join running core dump job > > > > > > Is there a way to programmatically wait for a previously initiated > > > virDomainCoreDumpWithFormat() where the process that started it died? > > I'm > > > looking at the API and don't seem to find anything relevant. I suppose I > > could > > > poll via virDomainGetJobStats(), but, ideally, I'd like a function that > > > would > > join > > > the dump job and return when the dump job finishes. > > > _______________________________________________ > > > Devel mailing list -- devel@lists.libvirt.org > > > To unsubscribe send an email to devel-le...@lists.libvirt.org > > > > I see there's qemuDumpWaitForCompletion(), looks promising. > > I've made some progress (added a > virHypervisorDriver.domainCoreDumpWait and the relevant scaffolding to > make 'virsh dump --wait' work), calling qemuDumpWaitForCompletion() is all > that's needed. > > However, it doesn't seem trivial to implement this in the test_driver. > First, IIUC testDomainCoreDumpWithFormat() gets an exclusive lock on the > domain (haven't tested anything yet), so calling domainCoreDumpWait() > would block for the wrong reason. Is making > testDomainCoreDumpWithFormat() using asynchronous jobs internally > unavoidable? > Second, I want to test behaviour in my application where (1) it calls > domainCoreDump(), (2) crashes before domainCoreDump() finishes, (3) then > my application starts again and looks for a pending dump job and (4) joins it > using domainCoreDumpWait(). I can't see an easy wait of faking a dump job > in the test_driver when it starts. How about adding persistent tasks, which I > can pre-populate before starting my application, or fake jobs via an > environment variable, so that when the test_driver starts it can internally > continue them? E.g. we can specify how long to run the job for and > domainCoreDumpWait() add a sleep for that long.
I ended up using and environment variable in the test_driver to fake jobs, so the application under test doesn't need to know anything. Would something like that be accepted? > > I'm open to suggestions. I have managed to implement a PoC by introducing virDomainJobWait(), which checks the job type and if it's a dump it calls qemuDumpWaitForCompletion(), purely because it's the easiest thing to do (it fails with VIR_ERR_OPERATION_INVALID for all other operations). We'd like to implement this for all other job types and I'm looking for some pointers, is virCondWaitUntil(&priv->job.asyncCond, &obj->parent.lock) all that's required? (And return priv->job.error?) Also, as I explained earlier, I want to implement joining a potentially existing dump job. In my specific use case, I want to either join an ongoing dump job if it exists, otherwise start a new one. I do this by calling virDomainGetJobStats(), but I'm thinking whether we could add a new, optional dump flag, e.g. 'join' which would make virDomainCoreDumpWithFormat do all this internally. Would something like that be accepted upstream. _______________________________________________ Devel mailing list -- devel@lists.libvirt.org To unsubscribe send an email to devel-le...@lists.libvirt.org
