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Subject: Re: [PATCH 1/2] SCHED: Generic hooks for trapping task preemption
From: Rusty Russell <rusty@rustcorp.com.au>
To: Avi Kivity <avi@qumranet.com>
Cc: kvm-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org,
       Ingo Molnar <mingo@elte.hu>, shaohua.li@intel.com
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Date: Thu, 12 Jul 2007 15:14:53 +1000
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On Wed, 2007-07-11 at 18:55 +0300, Avi Kivity wrote:
> +	fire_sched_out_preempt_hooks(current);
>    	prepare_lock_switch(rq, next);
>  	prepare_arch_switch(next);

Damn, I just found a use for this in lguest.

Any chance of handing "next" to the sched_out hook so we can optimize
the lguest <-> lguest switch?

FYI, lguest turns off PGE globally when you load the module, because
turning it off on each guest entry v. slow.  With these hooks I can be
far smarter...

Thanks!
Rusty.