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From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: Zhenzhong Duan <zhenzhong.duan@oracle.com>,
	Jeremy Fitzhardinge <jeremy@goop.org>
Cc: linux-x86_64@vger.kernel.org, linux-kernel@vger.kernel.org,
	xen-devel@lists.xensource.com
Subject: Re: [PATCH] cpu idle ticks show twice in xen pvm guest
Date: Mon, 10 Oct 2011 11:53:19 -0400	[thread overview]
Message-ID: <20111010155319.GA29140@phenom.oracle.com> (raw)
In-Reply-To: <ce19ea02-45e6-465a-a4c8-b5d74bf8c2ad@default>

On Wed, Oct 05, 2011 at 10:11:58PM -0700, Zhenzhong Duan wrote:
> Run below test on xen pvm.
> # x=$(cat /proc/stat | grep cpu0 | awk '{print $5}') && sleep 60  \
> && y=$(cat /proc/stat | grep cpu0 | awk '{print $5}') \
> && echo -e  "X:$x\nY:$y\nIDLE:" $(echo "scale=3; ($y-$x)/6000*100" | bc)
> 
> @ X:58562301
> @ Y:58574282
> @ IDLE: 199.600
> 
> Normal idle percent should be around 100%.
> xen_timer_interrupt called account_idle_ticks to account hypervisor stolen idle ticks 
> but these ticks will be accounted again when idle ticks restarted.
> 
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
> Signed-off-by: Joe Jin <joe.jin@oracle.com>

Please in the future also CC the maintainers (you can get that using
the scripts/get_maintainer.pl).

Jeremy, any thoughts?
> 
> diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
> index 163b467..5dcbc91 100644
> --- a/arch/x86/xen/time.c
> +++ b/arch/x86/xen/time.c
> @@ -151,7 +151,6 @@ static void do_stolen_accounting(void)
>  
>  	ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked);
>  	__this_cpu_write(xen_residual_blocked, blocked);
> -	account_idle_ticks(ticks);
>  }
>  
>  /* Get the TSC speed from Xen */
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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  reply	other threads:[~2011-10-10 15:53 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-06  5:11 [PATCH] cpu idle ticks show twice in xen pvm guest Zhenzhong Duan
2011-10-10 15:53 ` Konrad Rzeszutek Wilk [this message]
2011-10-10 20:00   ` Jeremy Fitzhardinge
2011-10-11  3:16     ` DuanZhenzhong
2011-12-09 15:47     ` Ferenc Wagner
2011-12-17 21:46       ` Konrad Rzeszutek Wilk
2011-12-19 17:53         ` Ferenc Wagner

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