Re: [Patch] continue_hypercall_on_cpu rework using tasklets

[Juergen Gross <juergen.gross@ts.fujitsu.com>]

Keir Fraser wrote:
> On 13/04/2010 14:19, "Juergen Gross" <juergen.gross@ts.fujitsu.com> wrote:
> 
>> attached is a patch to use tasklets for continue_hypercall_on_cpu instead of
>> temporarily pinning the vcpu to the target physical cpu.
>>
>> This is thought as base for cpupools as Keir requested to get rid of the
>> "borrow cpu" stuff in my original solution.
> 
> Why do you change the interface of continue_hypercall_on_cpu()? What's a
> 'hdl' anyway?

I need a way to find the migrate_info structure in case of nested calls of
continue_hypercall_on_cpu(). Originally this was done by storing it in the
vcpu structure, but this can't be done any more using tasklets. In my first
attempt I saved it in the per-cpu area, but this approach isn't working if
continue_hypercall_on_cpu() is called concurrently. So the cleanest way is
to pass it via a parameter.
'hdl' is just a 'handle'.


Juergen

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