Re: [libvirt] [PATCH 3/4] qemu: Don't remove hash entry of other domains
On 2013年02月11日 18:59, Daniel P. Berrange wrote:
On Fri, Feb 08, 2013 at 09:08:01PM +0800, Osier Yang wrote:
> qemuProcessStart invokes qemuProcessStop when fails, to avoid
> removing hash entry which belongs to other domain(s), this introduces
> a new virBitmapPtr argument for qemuProcessStop. And qemuProcessStart
> sets the bit for the disk only if it's successfully added into the
> hash table. Thus if the argument is provided for qemuProcessStop, it
> can't remove the hash entry belongs to other domain(s).
I find this approach rather dubious - IMHO it is a sign that you're
not recording enough information in the shared disk hash. eg perhaps
the hash ought to be recording the UUID of each VM that is holding
a reference. That way you're protected from qemuProcessStop() trying
todo something wrong.
I'm doubting about if it's really deserved to maintain a bunch of
arrays in the hash entry. As we only need the recording for
qemuProcessStart, it's much simpler to only use a bitmap to record
the added disks for a VM in qemuProcessStart from my p.o.v.
Osier