x86: Return IRQ_SET_MASK_OK_NOCOPY from irq affinity functions

The interrupt chip irq_set_affinity() functions copy the affinity mask
to irq_data->affinity but return 0, i.e. IRQ_SET_MASK_OK.
IRQ_SET_MASK_OK causes the core code to do another redundant copy.

Return IRQ_SET_MASK_OK_NOCOPY to avoid this.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Cliff Wickman <cpw@sgi.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Keping Chen <chenkeping@huawei.com>
Link: http://lkml.kernel.org/r/1333120296-13563-4-git-send-email-jiang.liu@huawei.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/apic/io_apic.c

@@ -2270,6 +2270,7 @@ ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
 		/* Only the high 8 bits are valid. */
 		dest = SET_APIC_LOGICAL_ID(dest);
 		__target_IO_APIC_irq(irq, dest, data->chip_data);
+		ret = IRQ_SET_MASK_OK_NOCOPY;
 	}
 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 	return ret;
@@ -3092,7 +3093,7 @@ msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
 
 	__write_msi_msg(data->msi_desc, &msg);
 
-	return 0;
+	return IRQ_SET_MASK_OK_NOCOPY;
 }
 #endif /* CONFIG_SMP */
 
@@ -3214,7 +3215,7 @@ dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
 
 	dmar_msi_write(irq, &msg);
 
-	return 0;
+	return IRQ_SET_MASK_OK_NOCOPY;
 }
 
 #endif /* CONFIG_SMP */
@@ -3267,7 +3268,7 @@ static int hpet_msi_set_affinity(struct irq_data *data,
 
 	hpet_msi_write(data->handler_data, &msg);
 
-	return 0;
+	return IRQ_SET_MASK_OK_NOCOPY;
 }
 
 #endif /* CONFIG_SMP */
@@ -3340,7 +3341,7 @@ ht_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
 		return -1;
 
 	target_ht_irq(data->irq, dest, cfg->vector);
-	return 0;
+	return IRQ_SET_MASK_OK_NOCOPY;
 }
 
 #endif

arch/x86/platform/uv/uv_irq.c

@@ -222,7 +222,7 @@ uv_set_irq_affinity(struct irq_data *data, const struct cpumask *mask,
 	if (cfg->move_in_progress)
 		send_cleanup_vector(cfg);
 
-	return 0;
+	return IRQ_SET_MASK_OK_NOCOPY;
 }
 
 /*