From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerd Hoffmann Subject: Re: [PATCH 1/4] Add helper functions for paravirtual clocksources. Date: Mon, 28 Apr 2008 10:54:48 +0200 Message-ID: <481590D8.1070401@redhat.com> References: <1209026228-9113-1-git-send-email-kraxel@redhat.com> <1209026228-9113-2-git-send-email-kraxel@redhat.com> <5d6222a80804240611o69ffb475pd2a58c78349a54a2@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel@lists.sourceforge.net To: Glauber Costa Return-path: In-Reply-To: <5d6222a80804240611o69ffb475pd2a58c78349a54a2@mail.gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces@lists.sourceforge.net Errors-To: kvm-devel-bounces@lists.sourceforge.net List-Id: kvm.vger.kernel.org Glauber Costa wrote: > This is not exactly what kvm does. For us, wallclock read and system > time reads are decoupled operations, controlled by different msrs. Same for xen. Although both live in the shared_info page they are updated independently (and the wall clock is updated much less frequently). > This function might exist, but in this case, it have to be wrapped > around a kvm_read_wallclock(), that does the msr read. (I'm not sure > whether or not you do it in your later patches, doing sequential reads > :-) ) It is, as you have seen in the kvm patch ;) What is the reason to handle the two clock msrs in different ways btw? I think it would be better to have both msrs work the same way though, i.e. the wallclock msr should have a enable bit and should auto-update too. cheers, Gerd -- http://kraxel.fedorapeople.org/xenner/ ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone