From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Borntraeger Subject: [patch 0/3] RFC: provide synchronous registers in kvm_run Date: Thu, 22 Dec 2011 12:56:46 +0100 Message-ID: <20111222115646.248800653@de.ibm.com> Cc: Carsten Otte , Alexander Graf , Jens Freimann , Cornelia Huck , Heiko Carstens , Martin Schwidefsky , KVM To: Avi Kivity , Marcelo Tossati Return-path: Received: from e06smtp13.uk.ibm.com ([195.75.94.109]:46456 "EHLO e06smtp13.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752398Ab1LVMA7 (ORCPT ); Thu, 22 Dec 2011 07:00:59 -0500 Received: from /spool/local by e06smtp13.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 22 Dec 2011 12:00:58 -0000 Received: from d06av02.portsmouth.uk.ibm.com (d06av02.portsmouth.uk.ibm.com [9.149.37.228]) by d06nrmr1806.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id pBMC0tLq2900054 for ; Thu, 22 Dec 2011 12:00:55 GMT Received: from d06av02.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av02.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id pBMC0sgV020259 for ; Thu, 22 Dec 2011 05:00:54 -0700 Sender: kvm-owner@vger.kernel.org List-ID: Avi, Marcelo, currently userspace can access guest registers via several ioctls. Some of these registers might be useful very often. Here the system call overhead for ioctl can make an exit more expensive than necessary. In a discussion with Alex Graf we concluded that it might be beneficial to have a subset of registers available in kvm_run. (The ioctls will also be available). This series provides a prototype implementation together with two example users for s390. Opionions?