From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raghavendra K T Subject: Re: [PATCH delta V13 14/14] kvm : Paravirtual ticketlocks support for linux guests running on KVM hypervisor Date: Wed, 14 Aug 2013 01:32:11 +0530 Message-ID: <20130813200211.GA27811@linux.vnet.ibm.com> References: <1376058122-8248-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com> <1376058122-8248-15-git-send-email-raghavendra.kt@linux.vnet.ibm.com> <20130810193849.GA25260@linux.vnet.ibm.com> <520A620B.6070702@zytor.com> <20130813165552.GA6795@gmail.com> Reply-To: Raghavendra K T Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Return-path: Content-Disposition: inline In-Reply-To: <20130813165552.GA6795@gmail.com> Sender: linux-doc-owner@vger.kernel.org To: Ingo Molnar Cc: "H. Peter Anvin" , Raghavendra K T , linux-kernel@vger.kernel.org, x86@kernel.org, jeremy@goop.org, konrad.wilk@oracle.com, gleb@redhat.com, pbonzini@redhat.com, gregkh@suse.de, peterz@infradead.org, tglx@linutronix.de, agraf@suse.de, riel@redhat.com, avi.kivity@gmail.com, habanero@linux.vnet.ibm.com, chegu_vinod@hp.com, ouyang@cs.pitt.edu, drjones@redhat.com, attilio.rao@citrix.com, linux-doc@vger.kernel.org, torvalds@linux-foundation.org, kvm@vger.kernel.org, andi@firstfloor.org, xen-devel@lists.xensource.com, virtualization@lists.linux-foundation.org, stefano.stabellini@eu.citrix.com, mtosatti@redhat.com, srivatsa.vaddagiri@gmail.com, Srivatsa Vaddagiri , Suzuki Poulose List-Id: xen-devel@lists.xenproject.org * Ingo Molnar [2013-08-13 18:55:52]: > Would be nice to have a delta fix patch against tip:x86/spinlocks, which > I'll then backmerge into that series via rebasing it. > There was a namespace collision of PER_CPU lock_waiting variable when we have both Xen and KVM enabled. Perhaps this week wasn't for me. Had run 100 times randconfig in a loop for the fix sent earlier :(. Ingo, below delta patch should fix it, IIRC, I hope you will be folding this back to patch 14/14 itself. Else please let me. I have already run allnoconfig, allyesconfig, randconfig with below patch. But will test again. This should apply on top of tip:x86/spinlocks. ---8<--- From: Raghavendra K T Fix Namespace collision for lock_waiting Signed-off-by: Raghavendra K T --- diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index d442471..b8ef630 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -673,7 +673,7 @@ struct kvm_lock_waiting { static cpumask_t waiting_cpus; /* Track spinlock on which a cpu is waiting */ -static DEFINE_PER_CPU(struct kvm_lock_waiting, lock_waiting); +static DEFINE_PER_CPU(struct kvm_lock_waiting, klock_waiting); static void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) { @@ -685,7 +685,7 @@ static void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) if (in_nmi()) return; - w = &__get_cpu_var(lock_waiting); + w = &__get_cpu_var(klock_waiting); cpu = smp_processor_id(); start = spin_time_start(); @@ -756,7 +756,7 @@ static void kvm_unlock_kick(struct arch_spinlock *lock, __ticket_t ticket) add_stats(RELEASED_SLOW, 1); for_each_cpu(cpu, &waiting_cpus) { - const struct kvm_lock_waiting *w = &per_cpu(lock_waiting, cpu); + const struct kvm_lock_waiting *w = &per_cpu(klock_waiting, cpu); if (ACCESS_ONCE(w->lock) == lock && ACCESS_ONCE(w->want) == ticket) { add_stats(RELEASED_SLOW_KICKED, 1);