Re: [Qemu-devel] [PATCH] Make cpu_single_env thread local (Linux only for now)

[Jan Kiszka]

On 2011-10-26 18:27, Andreas Färber wrote:
> Am 26.10.2011 18:02, schrieb Jan Kiszka:
>> On 2011-10-26 17:18, Peter Maydell wrote:
>>> On 26 October 2011 16:13, Jan Kiszka <address@hidden> wrote:
>>>> My point is that it is fine to use for per-vcpu variables because:
>>>>  - they are single-threaded in TCG mode
>>>>  - they are multi-threaded in KVM mode, but that's only affecting Linux
>>>>   hosts for which this TLS wrapper is already usable
>>>
>>> Oh, I see. Feel free to suggest reworded comment text :-)
>>
>> /* Dummy implementations -- we can get away with this because
>>  *  - we confine the use to per-VCPU variables
>>  *  - only linux-user supports multiple VCPU threads
>>  *  - TCG system mode is single-threaded regarding VCPUs
> 
>>  *  - KVM system mode is multi-threaded but limited to Linux
> 
> There was a port of KVM to illumos-derived SmartOS. But I don't see an
> easy way to error out on non-Linux KVM hosts without breaking TCG, too.

And I would be surprised to see them running with zero QEMU patches. So
they are not upstream, thus slightly outside our radar.

Jan

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