Re: deadlock in the credit2

[Eunbyung Park <silverbottlep@gmail.com>]

>>> if ( d == current->domain )
>>> vcpu_schedule_lock_irq(current);
>>>
>>> It was very hard to understan for me..:) What does it exactly mean?
>> You're asking what "current" means?  "current" is a macro that always
>> resolves to the vcpu which is running on the current processor.
>>
>> sched_adjust() seems to be trying to avoid scheduling races in general
>> by pausing all vcpus before calling the per-scheduler function.  But
>> if a VM is calling the op on itself, the vcpu making the hypercall
>> can't pause itself.  So in that case (current->domain == d) will be
>> true, so sched_adjust() grab the schedule lock of that vm instead.
>>
>> But really all that locking should be handled in the scheduler
>> function, not by the generic code.  It knows best what needs to be
>> locked when.
This was what I really wanted to ask about.
Now I can understand what the generic scheduler code was going to say.
Thanks for your kindness.

--
Best Regards,
Eunbyung Park