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Subject: Re: disabling group leader perf_event
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On 09/06/2010 03:43 PM, Ingo Molnar wrote:
>> > Yes. The filter engine is a safe, in-kernel interpreted language in
>> > the making. The C syntax was chosen because it's close to the heart
>> > of every kernel developer.
>> >
* Avi Kivity <avi@redhat.com> wrote:
>> > It might make sense to bring this concept a few steps further. Looks
>> > rather complex but also rather cool ...
>>
>> Is this a roundabout way of saying "jit"?

On Mon, Sep 6, 2010 at 3:59 PM, Ingo Molnar <mingo@elte.hu> wrote:
> Partly. I'm not sure we want to actually upload programs in bytecode
> form. ASCII is just fine - just like a .gz Javascript is fine for web
> apps. (and in most cases compresses down better than the bytecode
> equivalent)
>
> So a clear language (the simpler initially the better) plus an in-kernel
> compiler.
>
> This could be used for far more than just instrumentation: IMO security
> policies could be expressed in such a way. (Simplified, they are quite
> similar to filters installed on syscall entry/exit, with the ability of
> the filter to influence whether the syscall is performed.)

Filter engine? I've never heard of it before. Where does it live?