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Message-ID: <1347308360.2124.59.camel@twins>
Subject: Re: [RFC][PATCH] Improving directed yield scalability for PLE
 handler
From: Peter Zijlstra <peterz@infradead.org>
To: habanero@linux.vnet.ibm.com
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>,
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        Gleb Natapov <gleb@redhat.com>,
        Srivatsa Vaddagiri <srivatsa.vaddagiri@gmail.com>
Date: Mon, 10 Sep 2012 22:19:20 +0200
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On Mon, 2012-09-10 at 15:12 -0500, Andrew Theurer wrote:
> +       /*
> +        * if the target task is not running, then only yield if the
> +        * current task is in guest mode
> +        */
> +       if (!(p_rq->curr->flags & PF_VCPU))
> +               goto out_irq; 

This would make yield_to() only ever work on KVM, not that I mind this
too much, its a horrid thing and making it less useful for (ab)use is a
good thing, still this probably wants mention somewhere :-)