Re: [Qemu-block] [PATCH RFC v3 4/8] block: convert ThrottleGroup to object with QOM

[Alberto Garcia]

On Mon 26 Jun 2017 06:58:32 PM CEST, Manos Pitsidianakis wrote:
> On Mon, Jun 26, 2017 at 03:52:34PM +0100, Stefan Hajnoczi wrote:
>>On Fri, Jun 23, 2017 at 03:46:56PM +0300, Manos Pitsidianakis wrote:
>>> +static bool throttle_group_exists(const char *name)
>>> +{
>>> +    ThrottleGroup *iter;
>>> +    bool ret = false;
>>> +
>>> +    qemu_mutex_lock(&throttle_groups_lock);
>>
>>Not sure if this lock or the throttle_groups list are necessary.

As Manos says accesses to the throttle_groups list need to be locked.

What I don't like at first sight is the code duplication in
throttle_group_incref() and throttle_group_obj_complete().

>>Have you seen iothread.c:qmp_query_iothreads()?  All objects are put
>>into a container (the parent object), so you can just iterate over its
>>children.  There's no need for a separate list because QOM already has
>>all the objects.

I haven't looked into this yet but it could be a solution.

Berto