[libvirt] [PATCH] qemu: unlock qemu driver before return

[Wen Congyang]

At 03/30/2011 09:49 AM, Hu Tao Write:
> ---
>  src/qemu/qemu_driver.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index 104e92d..6e3edde 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -2068,12 +2068,14 @@ static int qemudDomainSave(virDomainPtr dom, const char *path)
>              qemuReportError(VIR_ERR_OPERATION_FAILED,
>                              "%s", _("Invalid save image format specified "
>                                      "in configuration file"));
> +            qemuDriverUnlock(driver);
>              return -1;
>          }
>          if (!qemudCompressProgramAvailable(compressed)) {
>              qemuReportError(VIR_ERR_OPERATION_FAILED,
>                              "%s", _("Compression program for image format "
>                                      "in configuration file isn't available"));
> +            qemuDriverUnlock(driver);
>              return -1;
>          }
>      }

I checked all the place where calling qemuDriverLock(), and I found 2 similar problem:
1. qemudStartup():
=================
    *qemuDriverUnlock(qemu_driver);*

    qemuAutostartDomains(qemu_driver);

    qemu_driver->workerPool = virThreadPoolNew(0, 1, processWatchdogEvent, qemu_driver);
    if (!qemu_driver->workerPool)
        goto error;

    if (conn)
        virConnectClose(conn);

    return 0;

out_of_memory:
    virReportOOMError();
error:
    if (qemu_driver)
        *qemuDriverUnlock(qemu_driver);*

=================

We unlock qemu_driver twice when virThreadPoolNew() failed.
I think we should lock qemu_driver again before calling virThreadPoolNew().

2. processWatchdogEvent():
=================
    switch (wdEvent->action) {
    case VIR_DOMAIN_WATCHDOG_ACTION_DUMP:
        {
....
            qemuDriverLock(driver);
            virDomainObjLock(wdEvent->vm);

            if (qemuDomainObjBeginJobWithDriver(driver, wdEvent->vm) < 0)
                break;

            if (!virDomainObjIsActive(wdEvent->vm)) {
                qemuReportError(VIR_ERR_OPERATION_INVALID,
                                "%s", _("domain is not running"));
                break;
            }

=================
We lock qemu_driver and vm, but we do not unlock them when qemuDomainObjBeginJobWithDriver()
failed or the vm is not running.