Subject: [PATCH] xen: use proper percpu variable for cpu_evtchn_mask

cpu_evtchn_mask is a per-cpu mask of event channels, so it should
be implemented as a proper per_cpu variable.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index abad71b..4443b0f 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -93,14 +93,11 @@ static struct irq_info irq_info[NR_IRQS];
 static int evtchn_to_irq[NR_EVENT_CHANNELS] = {
 	[0 ... NR_EVENT_CHANNELS-1] = -1
 };
-struct cpu_evtchn_s {
-	unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG];
-};
-static struct cpu_evtchn_s *cpu_evtchn_mask_p;
-static inline unsigned long *cpu_evtchn_mask(int cpu)
-{
-	return cpu_evtchn_mask_p[cpu].bits;
-}
+
+#define NR_EVENT_CHANNEL_LONGS	(NR_EVENT_CHANNELS/BITS_PER_LONG)
+static DEFINE_PER_CPU(unsigned long,
+		      cpu_evtchn_mask[NR_EVENT_CHANNEL_LONGS]) =
+	{[0 ... NR_EVENT_CHANNEL_LONGS-1] = ~0};
 
 /* Xen will never allocate port zero for any purpose. */
 #define VALID_EVTCHN(chn)	((chn) != 0)
@@ -223,7 +220,7 @@ static inline unsigned long active_evtchns(unsigned int cpu,
 					   unsigned int idx)
 {
 	return (sh->evtchn_pending[idx] &
-		cpu_evtchn_mask(cpu)[idx] &
+		per_cpu(cpu_evtchn_mask, cpu)[idx] &
 		~sh->evtchn_mask[idx]);
 }
 
@@ -236,8 +233,8 @@ static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
 	cpumask_copy(irq_to_desc(irq)->affinity, cpumask_of(cpu));
 #endif
 
-	__clear_bit(chn, cpu_evtchn_mask(cpu_from_irq(irq)));
-	__set_bit(chn, cpu_evtchn_mask(cpu));
+	__clear_bit(chn, per_cpu(cpu_evtchn_mask, cpu_from_irq(irq)));
+	__set_bit(chn, per_cpu(cpu_evtchn_mask, cpu));
 
 	irq_info[irq].cpu = cpu;
 }
@@ -253,8 +250,6 @@ static void init_evtchn_cpu_bindings(void)
 		cpumask_copy(desc->affinity, cpumask_of(0));
 	}
 #endif
-
-	memset(cpu_evtchn_mask(0), ~0, sizeof(cpu_evtchn_mask(0)));
 }
 
 static inline void clear_evtchn(int port)
@@ -928,10 +923,6 @@ void __init xen_init_IRQ(void)
 {
 	int i;
 
-	cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s),
-				    GFP_KERNEL);
-	BUG_ON(cpu_evtchn_mask_p == NULL);
-
 	init_evtchn_cpu_bindings();
 
 	/* No event channels are 'live' right now. */