Re: [PATCH v2 COLOPre 07/13] tools/libxl: Update libxl__domain_unpause() to support qemu-xen

[Yang Hongyang <yanghy@cn.fujitsu.com>]

On 06/16/2015 12:22 AM, Wei Liu wrote:
> On Mon, Jun 15, 2015 at 09:29:55AM +0800, Yang Hongyang wrote:
>>
>>
>> On 06/12/2015 08:33 PM, Wei Liu wrote:
>>> On Mon, Jun 08, 2015 at 11:43:11AM +0800, Yang Hongyang wrote:
>>>> Currently, libxl__domain_unpause() only supports
>>>> qemu-xen-traditional. Update it to support qemu-xen.
>>>>
>>>> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
>>>> Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>
>>>
>>> This looks very similar to an existing function called
>>> libxl__domain_resume_device_model. Maybe you don't need to invent a new
>>> function.
>>>
>>>> ---
>>>>   tools/libxl/libxl.c | 42 +++++++++++++++++++++++++++++++++---------
>>>>   1 file changed, 33 insertions(+), 9 deletions(-)
>>>>
>>>> diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
>>>> index d5691dc..5c843c2 100644
>>>> --- a/tools/libxl/libxl.c
>>>> +++ b/tools/libxl/libxl.c
>>>> @@ -933,10 +933,37 @@ out:
>>>>       return AO_INPROGRESS;
>>>>   }
>>>>
>>>> -int libxl__domain_unpause(libxl__gc *gc, uint32_t domid)
>>>> +static int libxl__domain_unpause_device_model(libxl__gc *gc, uint32_t domid)
>>>>   {
>>>>       char *path;
>>>>       char *state;
>>>> +
>>>> +    switch (libxl__device_model_version_running(gc, domid)) {
>>>> +    case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: {
>>>> +        uint32_t dm_domid = libxl_get_stubdom_id(CTX, domid);
>>>> +
>>>> +        path = libxl__device_model_xs_path(gc, dm_domid, domid, "/state");
>>>> +        state = libxl__xs_read(gc, XBT_NULL, path);
>>>> +        if (state != NULL && !strcmp(state, "paused")) {
>>>
>>> The only difference between your function and
>>> libxl__domain_unpause_device_model is the check for "state" node. I
>>> think you can just add the check to libxl__domain_resume_device_model
>>> and use that function.
>>
>> I'm not sure if we change the existing function's behavior will affect the
>> existing callers, if there's no problem to do so, I will do as what you
>> said in the next version.
>>
>
> Qemu-dm currently has several states. libxl__domain_resume_device_model
> doesn't check the state and writes unconditionally. I think checking
> before writing would be an improvement.

fixed, thank you!

>
> Wei.
>
>>>
>>> Wei.
>>> .
>>>
>>
>> --
>> Thanks,
>> Yang.
> .
>

-- 
Thanks,
Yang.