From 70dd4998cb85f0ecd6ac892cc7232abefa432efb Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 16 Apr 2013 14:34:45 -0400 Subject: [PATCH] xen/spinlock: Disable IRQ spinlock (PV) allocation on PVHVM See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23 (xen: disable PV spinlocks on HVM) for details. But we did not disable it everywhere - which means that when we boot as PVHVM we end up allocating per-CPU irq line for spinlock. This fixes that. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/spinlock.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 47ae032f8d97..8b54603ce816 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -367,6 +367,13 @@ void __cpuinit xen_init_lock_cpu(int cpu) WARN(per_cpu(lock_kicker_irq, cpu) > 0, "spinlock on CPU%d exists on IRQ%d!\n", cpu, per_cpu(lock_kicker_irq, cpu)); + /* + * See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23 + * (xen: disable PV spinlocks on HVM) + */ + if (xen_hvm_domain()) + return; + name = kasprintf(GFP_KERNEL, "spinlock%d", cpu); irq = bind_ipi_to_irqhandler(XEN_SPIN_UNLOCK_VECTOR, cpu, @@ -385,12 +392,26 @@ void __cpuinit xen_init_lock_cpu(int cpu) void xen_uninit_lock_cpu(int cpu) { + /* + * See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23 + * (xen: disable PV spinlocks on HVM) + */ + if (xen_hvm_domain()) + return; + unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL); per_cpu(lock_kicker_irq, cpu) = -1; } void __init xen_init_spinlocks(void) { + /* + * See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23 + * (xen: disable PV spinlocks on HVM) + */ + if (xen_hvm_domain()) + return; + BUILD_BUG_ON(sizeof(struct xen_spinlock) > sizeof(arch_spinlock_t)); pv_lock_ops.spin_is_locked = xen_spin_is_locked; -- 2.11.0