[PATCH 5/5] xen: events: use per-cpu variable for cpu_evtchn_mask

From: Ian Campbell
Date: Mon Oct 25 2010 - 12:23:53 EST


I can't see any reason why it isn't already.

Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
---
drivers/xen/events.c | 31 +++++++++++--------------------
1 files changed, 11 insertions(+), 20 deletions(-)

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 9b58505..144ff72 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -110,19 +110,9 @@ static int *pirq_to_irq;
static int nr_pirqs;

static int *evtchn_to_irq;
-struct cpu_evtchn_s {
- unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG];
-};

-static __initdata struct cpu_evtchn_s init_evtchn_mask = {
- .bits[0 ... (NR_EVENT_CHANNELS/BITS_PER_LONG)-1] = ~0ul,
-};
-static struct cpu_evtchn_s *cpu_evtchn_mask_p = &init_evtchn_mask;
-
-static inline unsigned long *cpu_evtchn_mask(int cpu)
-{
- return cpu_evtchn_mask_p[cpu].bits;
-}
+static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
+ cpu_evtchn_mask);

/* Xen will never allocate port zero for any purpose. */
#define VALID_EVTCHN(chn) ((chn) != 0)
@@ -301,7 +291,7 @@ 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]);
}

@@ -314,8 +304,8 @@ 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));

info_for_irq(irq)->cpu = cpu;
}
@@ -332,7 +322,11 @@ static void init_evtchn_cpu_bindings(void)
}
#endif

- memset(cpu_evtchn_mask(0), ~0, sizeof(struct cpu_evtchn_s));
+ printk(KERN_CRIT "%s: CPU0 at %p size %zd\n", __func__,
+ per_cpu(cpu_evtchn_mask, 0),
+ sizeof(per_cpu(cpu_evtchn_mask, 0)));
+ memset(per_cpu(cpu_evtchn_mask, 0), ~0,
+ sizeof(per_cpu(cpu_evtchn_mask, 0)));
}

static inline void clear_evtchn(int port)
@@ -1034,7 +1028,7 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
{
struct shared_info *sh = HYPERVISOR_shared_info;
int cpu = smp_processor_id();
- unsigned long *cpu_evtchn = cpu_evtchn_mask(cpu);
+ unsigned long *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu);
int i;
unsigned long flags;
static DEFINE_SPINLOCK(debug_lock);
@@ -1539,9 +1533,6 @@ void __init xen_init_IRQ(void)
int i, rc;
struct physdev_nr_pirqs op_nr_pirqs;

- cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s),
- GFP_KERNEL);
-
rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_nr_pirqs, &op_nr_pirqs);
if (rc < 0) {
nr_pirqs = nr_irqs;
--
1.5.6.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/