From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [Qemu-devel] qemu-kvm upstreaming: Do we need -no-kvm-pit and -no-kvm-pit-reinjection semantics? Date: Fri, 20 Jan 2012 12:13:27 +0100 Message-ID: <4F194C57.2030404@siemens.com> References: <4F17D56F.9090309@siemens.com> <20120119172532.GC11381@amt.cnet> <4F1854F9.6030400@siemens.com> <20120119175300.GE11381@amt.cnet> <4F185A88.5030904@siemens.com> <20120120101441.GA31499@amt.cnet> <4F194063.60307@siemens.com> <20120120103908.GT7180@jl-vm1.vm.bytemark.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , qemu-devel , kvm To: Jamie Lokier Return-path: Received: from thoth.sbs.de ([192.35.17.2]:21299 "EHLO thoth.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751546Ab2ATLNi (ORCPT ); Fri, 20 Jan 2012 06:13:38 -0500 In-Reply-To: <20120120103908.GT7180@jl-vm1.vm.bytemark.co.uk> Sender: kvm-owner@vger.kernel.org List-ID: On 2012-01-20 11:39, Jamie Lokier wrote: > Jan Kiszka wrote: >> Usability. Users should not have to care about individual tick-based >> clocks. They care about "my OS requires lost ticks compensation, yes or no". > > Conceivably an OS may require lost ticks compensation depending on > boot options given to the OS telling it which clock sources to use. > > However I like the idea of a global default, which you can set and all > the devices inherit it unless overridden in each device. OK, this sounds like a good option: add per-device control but also introduce global default. The latter can still be done later on. The only problem is that we should already come up with the right, generic control switch template. "reinject=on|off", as I did it for now for the PIT, is definitely not optimal. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux