From 3310bbedac497b793b96184e1b9b5da4f747d53a Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Mon, 26 Aug 2013 14:28:06 -0400 Subject: [PATCH] xen/spinlock: Don't setup xen spinlock IPI kicker if disabled. There is no need to setup this kicker IPI if we are never going to use the paravirtualized ticketlock mechanism. Signed-off-by: Konrad Rzeszutek Wilk Reviewed-by: David Vrabel --- arch/x86/xen/spinlock.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 71db82ce08c6..e1bff87766be 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -105,6 +105,7 @@ static DEFINE_PER_CPU(char *, irq_name); static DEFINE_PER_CPU(struct xen_lock_waiting, lock_waiting); static cpumask_t waiting_cpus; +static bool xen_pvspin __initdata = true; static void xen_lock_spinning(struct arch_spinlock *lock, __ticket_t want) { int irq = __this_cpu_read(lock_kicker_irq); @@ -223,6 +224,9 @@ void xen_init_lock_cpu(int cpu) int irq; char *name; + if (!xen_pvspin) + return; + WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n", cpu, per_cpu(lock_kicker_irq, cpu)); @@ -259,13 +263,15 @@ void xen_uninit_lock_cpu(int cpu) if (xen_hvm_domain()) return; + if (!xen_pvspin) + return; + unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL); per_cpu(lock_kicker_irq, cpu) = -1; kfree(per_cpu(irq_name, cpu)); per_cpu(irq_name, cpu) = NULL; } -static bool xen_pvspin __initdata = true; void __init xen_init_spinlocks(void) { @@ -305,6 +311,9 @@ static int __init xen_spinlock_debugfs(void) if (d_xen == NULL) return -ENOMEM; + if (!xen_pvspin) + return 0; + d_spin_debug = debugfs_create_dir("spinlocks", d_xen); debugfs_create_u8("zero_stats", 0644, d_spin_debug, &zero_stats);