Re: [PATCH v2] qemu: add a monitor to /proc/$pid when killing times out

[Boris Fiuczynski <fiuczy@xxxxxxxxxxxxx>]

On 7/19/24 3:29 PM, Daniel P. Berrangé wrote:
> > +static int
> > +qemuProcessInShutdownStartMonitor(virDomainObj *vm)
> > +{
> > +    qemuDomainObjPrivate *priv = vm->privateData;
> > +    qemuProcessInShutdownEventData *data;
> > +    int pidfd;
> > +    int ret = -1;
> > +
> > +    VIR_DEBUG("vm=%p name=%s pid=%lld pidMonitored=%d",
> > +              vm, vm->def->name, (long long)vm->pid,
> > +              priv->pidMonitored);
> > +
> > +    if (priv->pidMonitored >= 0) {
> > +        VIR_DEBUG("Monitoring qemu in-shutdown process %i already set up", vm->pid);
> > +        goto cleanup;
> > +    }
> > +
> > +    pidfd = syscall(SYS_pidfd_open, vm->pid, 0);
> > +    if (pidfd < 0) {
> > +        if (errno == ESRCH) /* process has already terminated */
> > +            ret = 1;
> > +        goto cleanup;
> > +    }
> > +
> > +    data = qemuProcessInShutdownEventDataNew(vm, pidfd);
> > +    if ((priv->pidMonitored = virEventAddHandle(pidfd,
> > +                                                VIR_EVENT_HANDLE_READABLE,
> > +                                                qemuProcessInShutdownPidfdCb,
> > +                                                data,
> > +                                                (virFreeCallback)qemuProcessInShutdownEventDataFree)) < 0) {
> > +        virReportError(VIR_ERR_INTERNAL_ERROR,
> > +                    _("failed to monitor qemu in-shutdown process %1$i"),
> > +                    vm->pid);
> > +        qemuProcessInShutdownEventDataFree(data);
> > +        goto cleanup;
> > +    }
> > +    VIR_DEBUG("Monitoring qemu in-shutdown process %i for termination", vm->pid);
> > +    ret = 0;
> > +
> > + cleanup:
> > +    return ret;
> > +}
> This will need some #ifdef-ery because I believe SYS_pidfd_open won't
> exist on all Linux versions we need, and certainly won't exist on
> non-Linux, and nor will syscall() fro that matter.

Ups, I forgot about that. Sending a v3 out.

--
Mit freundlichen Grüßen/Kind regards
   Boris Fiuczynski

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