From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Otte Subject: Re: RFC/patch portability: split kvm_vm_ioctl v3 Date: Tue, 30 Oct 2007 12:59:23 +0100 Message-ID: <47271C9B.1050804@de.ibm.com> References: <1192192452.7630.16.camel@cotte.boeblingen.de.ibm.com><1193327325.8345.9.camel@cotte.boeblingen.de.ibm.com> <1193400099.10970.8.camel@cotte.boeblingen.de.ibm.com> <10EA09EFD8728347A513008B6B0DA77A024CEC4D@pdsmsx411.ccr.corp.intel.com> <47270F9E.5080007@qumranet.com> <10EA09EFD8728347A513008B6B0DA77A024CEC54@pdsmsx411.ccr.corp.intel.com> Reply-To: carsteno-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Hollis Blanchard , "Zhang, Xiantao" , Avi Kivity To: "Dong, Eddie" Return-path: In-Reply-To: <10EA09EFD8728347A513008B6B0DA77A024CEC54-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@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 Dong, Eddie wrote: > BTW, how S390 user/kernel interrupt signal is communicated? Our s90host prototype does inject it from userspace, so there is no need to have a call for that. Nevertheless, I really love the lightweight exits that kvm has invented and I want to use it on s390 with kvm too. In that case, we'll have an interrupt facility in the kernel that is in terms of functionality close to the pic/lapic work for x86. For that, I think we could encode an interrupt number in an __u64 that has a platform specific helper function in userspace to generate that interrupt number: for x86 that would just equal the irq line, for s390 that would be more complex. The common kvm code can then take that __u64 number and call an architecture specific callback that injects the interrupt. In addition, I would love to be able to specify which target CPUs may receive that interrupt because our IPI equivalent comes out just like a regular interrupt on just one target CPU. That boils down to something like this: struct kvm_interrupt_data { __u64 interrupt_number; cpuset_t possible_target_cpus; } and an KVM_INJECT_INTERRUPT common ioctl for the vm to provide this. ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/