From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: Linux questions Date: Mon, 03 Dec 2007 11:24:35 +0000 Message-ID: <4753F583.76E4.0078.0@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org 1) Is there a particular reason Jeremy's sched_clock() variant isn't being used in linux-2.6.18-hg? Specifically, are there any known downsides to that approach? 2) What is the reason for the inconsistent use of rmb() vs. barrier() in time-xen.c? It would seem to me that rmb() should be sufficient in all cases. 3) Why is it that x86-64's __smp_call_function_single(), just like native, uses cpu_relax() in its wait-for-response loops, while __smp_call_function(= ) as well as i386's smp_call_function() use barrier(), other than native? Thanks, Jan