From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] RFC: Create kvm_arch_vcpu_runnable() function Date: Wed, 05 Dec 2007 12:06:33 +0200 Message-ID: <47567829.3080200@qumranet.com> References: <18646a9e5f19f5d51127.1196720126@basalt> <47555417.7020103@de.ibm.com> <47555BD2.1010305@qumranet.com> <47566A17.3040802@de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, kvm-ppc-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Hollis Blanchard To: carsteno-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org Return-path: In-Reply-To: <47566A17.3040802-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Carsten Otte wrote: > Avi Kivity wrote: > >> What about merging kvm_cpu_has_interrupt() into _runnable()? >> >> My feeling is that we can keep it separated. >> > On s390 there is a difference between has_interrupt and not runnable: > CPUs can be in stopped state, and they can be in enabled wait (enabled > for interrupts, similar to hlt state on x86) or in disabled wait > state. All those states indicate that the CPU is not runnable. > Interrupts on the other hand are typically floating between all > virtual CPUs and can be accepted by running CPUs only (that is either > running, or in enabled wait). > > I agree that we should keep it seperated. > On x86, running hlt with interrupts disabled is similar to your disabled wait. Interrupts in general are directed towards a specific cpu, though older processors supported round-robin or priority based dispatching. With extensive caches this is a performance loss, so the feature is not missed. Thanks for the clarification. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- SF.Net email is sponsored by: The Future of Linux Business White Paper from Novell. From the desktop to the data center, Linux is going mainstream. Let it simplify your IT future. http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4