From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [patch 3/3] kvm: wake up waitqueue before calling get_cpu() Date: Thu, 9 Apr 2009 06:24:30 -0300 Message-ID: <20090409092430.GB30211@amt.cnet> References: <20090407235853.309888494@suse.de> <20090407235902.542493610@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: rt-users , kvm@vger.kernel.org To: Jan Blunck Return-path: Content-Disposition: inline In-Reply-To: <20090407235902.542493610@suse.de> Sender: kvm-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org Acked-by: Marcelo Tosatti On Wed, Apr 08, 2009 at 01:58:56AM +0200, Jan Blunck wrote: > This moves the get_cpu() call down to be called after we wake up the > waiters. Therefore the waitqueue locks can savely be rt mutex. > > Signed-off-by: Jan Blunck > Signed-off-by: Sven-Thorsten Dietrich > --- > arch/x86/kvm/x86.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > Index: b/arch/x86/kvm/x86.c > =================================================================== > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -4229,7 +4229,7 @@ static void vcpu_kick_intr(void *info) > void kvm_vcpu_kick(struct kvm_vcpu *vcpu) > { > int ipi_pcpu = vcpu->cpu; > - int cpu = get_cpu(); > + int cpu; > > if (waitqueue_active(&vcpu->wq)) { > wake_up_interruptible(&vcpu->wq); > @@ -4239,6 +4239,7 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu > * We may be called synchronously with irqs disabled in guest mode, > * So need not to call smp_call_function_single() in that case. > */ > + cpu = get_cpu(); > if (vcpu->guest_mode && vcpu->cpu != cpu) > smp_call_function_single(ipi_pcpu, vcpu_kick_intr, vcpu, 0); > put_cpu(); > > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html