From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45662) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XMzHX-0004EG-9l for qemu-devel@nongnu.org; Thu, 28 Aug 2014 08:58:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XMzHO-0004Nm-UC for qemu-devel@nongnu.org; Thu, 28 Aug 2014 08:58:27 -0400 Received: from e06smtp13.uk.ibm.com ([195.75.94.109]:49539) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XMzHO-0004NI-GJ for qemu-devel@nongnu.org; Thu, 28 Aug 2014 08:58:18 -0400 Received: from /spool/local by e06smtp13.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 28 Aug 2014 13:58:16 +0100 Received: from b06cxnps4076.portsmouth.uk.ibm.com (d06relay13.portsmouth.uk.ibm.com [9.149.109.198]) by d06dlp01.portsmouth.uk.ibm.com (Postfix) with ESMTP id 0ACE617D805F for ; Thu, 28 Aug 2014 14:00:09 +0100 (BST) Received: from d06av06.portsmouth.uk.ibm.com (d06av06.portsmouth.uk.ibm.com [9.149.37.217]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id s7SCwDGA41746596 for ; Thu, 28 Aug 2014 12:58:13 GMT Received: from d06av06.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av06.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s7S7usTt006890 for ; Thu, 28 Aug 2014 03:56:54 -0400 Message-ID: <53FF2763.2010507@de.ibm.com> Date: Thu, 28 Aug 2014 14:58:11 +0200 From: Christian Borntraeger MIME-Version: 1.0 References: <1409227132-55354-1-git-send-email-jfrei@linux.vnet.ibm.com> In-Reply-To: <1409227132-55354-1-git-send-email-jfrei@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/5] s390x/kvm: avoid synchronize_rcu's in kernel List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jens Freimann , Alexander Graf , Cornelia Huck Cc: Paolo Bonzini , qemu-devel@nongnu.org On 28/08/14 13:58, Jens Freimann wrote: > Whenever we call an ioctl from a wrong vcpu thread, the next ioctl will be > painfully slow because a synchronize_rcu thread has to be performed, therefore > involving all vcpu. > > This patch series forces most ioctls to run on the associated vcpu. > It speeds up all start/restart/reset operations involving cpus drastically. > > > David Hildenbrand (5): > kvm: run cpu state synchronization on target vcpu thread > s390x/kvm: run guest triggered resets on the target vcpu thread > s390x/kvm: execute sigp orders on the target vcpu thread > s390x/kvm: execute "system reset" cpu resets on the vcpu thread > s390x/kvm: execute the first cpu reset on the vcpu thread > > kvm-all.c | 18 ++++++++++++++++-- > target-s390x/cpu.c | 6 +++++- > target-s390x/cpu.h | 15 +++++++++++++++ > target-s390x/kvm.c | 23 ++++++++++++++++------- > target-s390x/misc_helper.c | 30 ++++++++---------------------- > 5 files changed, 60 insertions(+), 32 deletions(-) > Thanks. Applied 2-5 to https://github.com/borntraeger/qemu.git s390-next. Patch 1 will be taken care of in Paolos kvm tree. I will wait some more days before sending the pull request to give others a chance for feedback. Christian