From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pekka Enberg Subject: Re: [PATCH 0/3] kvm tools: remove periodic tick Date: Wed, 04 Sep 2013 12:23:14 +0300 Message-ID: <5226FC02.4060404@iki.fi> References: <1378231855-13834-1-git-send-email-jonathan.austin@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, penberg@kernel.org, marc.zyngier@arm.com, will.deacon@arm.com, Matt.Evans@arm.com To: Jonathan Austin Return-path: Received: from out3-smtp.messagingengine.com ([66.111.4.27]:51082 "EHLO out3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762241Ab3IDJXR (ORCPT ); Wed, 4 Sep 2013 05:23:17 -0400 In-Reply-To: <1378231855-13834-1-git-send-email-jonathan.austin@arm.com> Sender: kvm-owner@vger.kernel.org List-ID: On 9/3/13 9:10 PM, Jonathan Austin wrote: > This patch series removes kvm tool's periodic tick function in favour of a > thread that blocks waiting for input. The paths used for handling input are the > same as when using a periodic tick, but they're not called unless there is > actually input to be processed. > > On extremely slow platforms (eg FPGAs) the overhead involved in handling the > timer tick means it is possible to make progress at all inside the VM! This > patch addresses this problem. > > In doing this there are a number of small tidyups/cleanups that made sense, too: > - Use a #define for maximum number of term devices > - Refactor the method by which the virtio console handles input in order not to > - handle input too early > - handle input multiple times if the worker thread didn't immediately start > work. > - Rename the periodic_poll function to reflect the functional change > > Jonathan Austin (3): > kvm tools: use #define for maximum number of terminal devices > kvm tools: remove periodic tick in favour of a polling thread > kvm tools: stop virtio console doing unnecessary input handling > > tools/kvm/arm/kvm.c | 2 +- > tools/kvm/builtin-run.c | 13 ----------- > tools/kvm/include/kvm/kvm.h | 2 +- > tools/kvm/kvm.c | 50 ------------------------------------------- > tools/kvm/powerpc/kvm.c | 2 +- > tools/kvm/term.c | 38 +++++++++++++++++++++++++++++--- > tools/kvm/virtio/console.c | 23 +++++++++++++++++--- > tools/kvm/x86/kvm.c | 2 +- > 8 files changed, 59 insertions(+), 73 deletions(-) Seems reasonable to me. Marc, Will? Pekka