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Subject: Re: [PATCH] xen: add steal_clock support on x86
To: Juergen Gross <jgross@suse.com>, xen-devel@lists.xenproject.org,
        linux-kernel@vger.kernel.org
References: <1463573758-11441-1-git-send-email-jgross@suse.com>
Cc: sstabellini@kernel.org, david.vrabel@citrix.com
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <573C804F.6020708@oracle.com>
Date: Wed, 18 May 2016 10:46:39 -0400
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On 05/18/2016 08:15 AM, Juergen Gross wrote:
>  }
>  
> +void __init xen_time_setup_guest(void)
> +{
> +	pv_time_ops.steal_clock = xen_steal_clock;
> +
> +	static_key_slow_inc(&paravirt_steal_enabled);
> +	/*
> +	 * We can't set paravirt_steal_rq_enabled as this would require the
> +	 * capability to read another cpu's runstate info.
> +	 */
> +}

Won't we be accounting for stolen cycles twice now --- once from
steal_account_process_tick()->steal_clock() and second time from
do_stolen_accounting()?

-boris