From mboxrd@z Thu Jan  1 00:00:00 1970
From: Carsten Otte <cotte@de.ibm.com>
Date: Fri, 11 Jul 2008 07:34:07 +0000
Subject: Re: [PATCH 2/5] kvmtrace: make cycle calculation architecture aware
Message-Id: <48770CEF.6090102@de.ibm.com>
List-Id: <kvm-ppc.vger.kernel.org>
References: <1215439013-11480-1-git-send-email-ehrhardt@linux.vnet.ibm.com> <4874821F.4060509@linux.vnet.ibm.com> <1215615799.22935.1.camel@localhost.localdomain> <200807101822.16163.sheng.yang@intel.com> <48760F6D.5000709@qumranet.com>
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To: Avi Kivity <avi@qumranet.com>
Cc: "Yang, Sheng" <sheng.yang@intel.com>, kvm@vger.kernel.org, Hollis Blanchard <hollisb@us.ibm.com>, Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>, xiantao.zhang@intel.com, kvm-ppc@vger.kernel.org

Avi Kivity wrote:
> What is the overhead of ktime_get()?
I think I'd like an arch specific timestamp. This way we could use our 
clock-cycle-granularity-non-privileged-timestamp instruction ;-). If 
we need a common implementation, I don't think there's much difference 
between different syscalls in terms of overhead.