From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: [PATCH] KVM: Avoid using vmx instruction directly Date: Wed, 22 Nov 2006 01:10:58 -0800 Message-ID: <45641422.5090601@goop.org> References: <4563667B.2060209@goop.org> <4563F158.3060209@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, akpm-3NddpPZAyC0@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "H. Peter Anvin" Return-path: To: Avi Kivity In-Reply-To: <4563F158.3060209-atKUWr5tajBWk0Htik3J/w@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 Avi Kivity wrote: > Very interesting. > > Will it work on load/store architectures? Since all memory access is > through a register, won't the constraint generate a useless register > load (and a use of the variable)? Don't know; interesting question. It might be worth lobbying the gcc folks for an asm() constraint which means "pretend this is being read/written, but don't generate any code, and raise an error if the asm actually tries to use it". Or perhaps there's some way to do that already. On the other hand, load/store archs tend to have lots of registers anyway, so maybe it isn't a big deal. J ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV