From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 1FA2A6B004A for ; Wed, 6 Oct 2010 16:05:41 -0400 (EDT) Received: by fxm10 with SMTP id 10so6470032fxm.14 for ; Wed, 06 Oct 2010 13:05:38 -0700 (PDT) Date: Wed, 6 Oct 2010 22:05:20 +0200 From: Gleb Natapov Subject: Re: [PATCH v6 07/12] Add async PF initialization to PV guest. Message-ID: <20101006200520.GB4120@minantech.com> References: <1286207794-16120-1-git-send-email-gleb@redhat.com> <1286207794-16120-8-git-send-email-gleb@redhat.com> <20101005182554.GA1786@amt.cnet> <20101006105504.GV11145@redhat.com> <20101006144512.GC31423@amt.cnet> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101006144512.GC31423@amt.cnet> Sender: owner-linux-mm@kvack.org To: Marcelo Tosatti Cc: Gleb Natapov , kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, avi@redhat.com, mingo@elte.hu, a.p.zijlstra@chello.nl, tglx@linutronix.de, hpa@zytor.com, riel@redhat.com, cl@linux-foundation.org List-ID: On Wed, Oct 06, 2010 at 11:45:12AM -0300, Marcelo Tosatti wrote: > On Wed, Oct 06, 2010 at 12:55:04PM +0200, Gleb Natapov wrote: > > On Tue, Oct 05, 2010 at 03:25:54PM -0300, Marcelo Tosatti wrote: > > > On Mon, Oct 04, 2010 at 05:56:29PM +0200, Gleb Natapov wrote: > > > > Enable async PF in a guest if async PF capability is discovered. > > > > > > > > Signed-off-by: Gleb Natapov > > > > --- > > > > Documentation/kernel-parameters.txt | 3 + > > > > arch/x86/include/asm/kvm_para.h | 5 ++ > > > > arch/x86/kernel/kvm.c | 92 +++++++++++++++++++++++++++++++++++ > > > > 3 files changed, 100 insertions(+), 0 deletions(-) > > > > > > > > > > > +static int __cpuinit kvm_cpu_notify(struct notifier_block *self, > > > > + unsigned long action, void *hcpu) > > > > +{ > > > > + int cpu = (unsigned long)hcpu; > > > > + switch (action) { > > > > + case CPU_ONLINE: > > > > + case CPU_DOWN_FAILED: > > > > + case CPU_ONLINE_FROZEN: > > > > + smp_call_function_single(cpu, kvm_guest_cpu_notify, NULL, 0); > > > > > > wait parameter should probably be 1. > > Why should we wait for it? FWIW I copied this from somewhere (May be > > arch/x86/pci/amd_bus.c). > > So that you know its executed in a defined point in cpu bringup. > If I read code correctly CPU we are notified about is already running when callback is called, so I do not see what waiting for IPI to be processed will accomplish here. With many cpus we will make boot a little bit slower. I don't care too much though, so if you still think that 1 is required here I'll make it so. -- Gleb. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org