From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: system call time increase when turning on CONFIG_PARAVIRT
Date: Wed, 07 Mar 2007 16:55:40 -0800
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To: tim.c.chen@linux.intel.com
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Tim Chen wrote:
> It turned out that VDSO was turned off by CONFIG_PARAVIRT option,
> causing the system call to use inefficient int 0x80 which led to the
> increase system_call time I was seeing.  I noted that Ingo has caught
> this problem and proposed a patch to correct this issue in another mail
> thread.

Thanks for identifying this.  We'll be posting a more general fix for
COMPAT_VDSO soon which will address this.

    J

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Date: Wed, 07 Mar 2007 16:55:40 -0800
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: tim.c.chen@linux.intel.com
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Subject: Re: system call time increase when turning on CONFIG_PARAVIRT
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Tim Chen wrote:
> It turned out that VDSO was turned off by CONFIG_PARAVIRT option,
> causing the system call to use inefficient int 0x80 which led to the
> increase system_call time I was seeing.  I noted that Ingo has caught
> this problem and proposed a patch to correct this issue in another mail
> thread.

Thanks for identifying this.  We'll be posting a more general fix for
COMPAT_VDSO soon which will address this.

    J