From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55186) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZuHmj-00042u-Fy for qemu-devel@nongnu.org; Thu, 05 Nov 2015 05:28:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZuHmg-0008FV-9b for qemu-devel@nongnu.org; Thu, 05 Nov 2015 05:28:49 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51100) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZuHmg-0008FG-3z for qemu-devel@nongnu.org; Thu, 05 Nov 2015 05:28:46 -0500 References: <1446695464-27116-1-git-send-email-liang.z.li@intel.com> From: Paolo Bonzini Message-ID: <563B2F57.8010904@redhat.com> Date: Thu, 5 Nov 2015 11:28:39 +0100 MIME-Version: 1.0 In-Reply-To: <1446695464-27116-1-git-send-email-liang.z.li@intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [v2 0/2] Optimize the env->tsc update operation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Liang Li , qemu-devel@nongnu.org Cc: ehabkost@redhat.com, mst@redhat.com, mtosatti@redhat.com, quintela@redhat.com, m.gibula@beyond.pl, amit.shah@redhat.com, rth@twiddle.net On 05/11/2015 04:51, Liang Li wrote: > This patch set aims for reducing the live migration downtime. It > updates the env->tsc when stopping kvmclock with a new function. > Rather than using 'cpu_synchronize_all_states()', which updates the > whole CPU context just for updating the env->tsc. > > For a VM with 4 CPUs, this patch set can help to reduce the VM downtime > about 100us. > > Changes in v2: > * Simplify 'kvm_get_tsc()' function. > * Introduce a new function 'kvm_synchronize_all_tsc()' > > Liang Li (2): > kvmclock: add a new function to update env->tsc. > Revert "Introduce cpu_clean_all_dirty" > > cpus.c | 9 --------- > hw/i386/kvm/clock.c | 18 ++---------------- > include/sysemu/cpus.h | 1 - > include/sysemu/kvm.h | 8 -------- > kvm-all.c | 5 ----- > target-i386/kvm.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ > target-i386/kvm_i386.h | 1 + > 7 files changed, 48 insertions(+), 39 deletions(-) > Nice, I've applied these patches. Paolo