From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754655AbbCPNgX (ORCPT ); Mon, 16 Mar 2015 09:36:23 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:45169 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754318AbbCPNgG (ORCPT ); Mon, 16 Mar 2015 09:36:06 -0400 Message-Id: <20150316131613.720617163@infradead.org> User-Agent: quilt/0.61-1 Date: Mon, 16 Mar 2015 14:16:13 +0100 From: Peter Zijlstra To: Waiman.Long@hp.com Cc: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, peterz@infradead.org, paolo.bonzini@gmail.com, konrad.wilk@oracle.com, boris.ostrovsky@oracle.com, paulmck@linux.vnet.ibm.com, riel@redhat.com, torvalds@linux-foundation.org, raghavendra.kt@linux.vnet.ibm.com, david.vrabel@citrix.com, oleg@redhat.com, scott.norton@hp.com, doug.hatch@hp.com, linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, luto@amacapital.net Subject: [PATCH 0/9] qspinlock stuff -v15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Waiman, As promised; here is the paravirt stuff I did during the trip to BOS last week. All the !paravirt patches are more or less the same as before (the only real change is the copyright lines in the first patch). The paravirt stuff is 'simple' and KVM only -- the Xen code was a little more convoluted and I've no real way to test that but it should be stright fwd to make work. I ran this using the virtme tool (thanks Andy) on my laptop with a 4x overcommit on vcpus (16 vcpus as compared to the 4 my laptop actually has) and it both booted and survived a hackbench run (perf bench sched messaging -g 20 -l 5000). So while the paravirt code isn't the most optimal code ever conceived it does work. Also, the paravirt patching includes replacing the call with "movb $0, %arg1" for the native case, which should greatly reduce the cost of having CONFIG_PARAVIRT_SPINLOCKS enabled on actual hardware. I feel that if someone were to do a Xen patch we can go ahead and merge this stuff (finally!). These patches do not implement the paravirt spinlock debug stats currently implemented (separately) by KVM and Xen, but that should not be too hard to do on top and in the 'generic' code -- no reason to duplicate all that. Of course; once this lands people can look at improving the paravirt nonsense.