powerpc/mpic: Fix problem that affinity is not updated

Since commit 57b150cce8e004ddd36330490a68bfb59b7271e9, desc->affinity
of an irq is changed after calling desc->chip->set_affinity.
Therefore we need to fix the irq_choose_cpu() not to depend on the
desc->affinity for new mask.

Signed-off-by: Jiajun Wu <b06378@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 6 insertions, 13 deletions

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index aa9d06e5925b..470dc6c11d57 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -567,13 +567,11 @@ static void __init mpic_scan_ht_pics(struct mpic *mpic)
 #endif /* CONFIG_MPIC_U3_HT_IRQS */
 
 #ifdef CONFIG_SMP
-static int irq_choose_cpu(unsigned int virt_irq)
+static int irq_choose_cpu(const cpumask_t *mask)
 {
-        cpumask_t mask;
         int cpuid;
 
-        cpumask_copy(&mask, irq_to_desc(virt_irq)->affinity);
-        if (cpus_equal(mask, CPU_MASK_ALL)) {
+        if (cpumask_equal(mask, cpu_all_mask)) {
                 static int irq_rover;
                 static DEFINE_SPINLOCK(irq_rover_lock);
                 unsigned long flags;
@@ -594,20 +592,15 @@ static int irq_choose_cpu(unsigned int virt_irq)
 
                 spin_unlock_irqrestore(&irq_rover_lock, flags);
         } else {
-                cpumask_t tmp;
-
-                cpus_and(tmp, cpu_online_map, mask);
-
-                if (cpus_empty(tmp))
+                cpuid = cpumask_first_and(mask, cpu_online_mask);
+                if (cpuid >= nr_cpu_ids)
                         goto do_round_robin;
-
-                cpuid = first_cpu(tmp);
         }
 
         return get_hard_smp_processor_id(cpuid);
 }
 #else
-static int irq_choose_cpu(unsigned int virt_irq)
+static int irq_choose_cpu(const cpumask_t *mask)
 {
         return hard_smp_processor_id();
 }
@@ -816,7 +809,7 @@ int mpic_set_affinity(unsigned int irq, const struct cpumask *cpumask)
         unsigned int src = mpic_irq_to_hw(irq);
 
         if (mpic->flags & MPIC_SINGLE_DEST_CPU) {
-                int cpuid = irq_choose_cpu(irq);
+                int cpuid = irq_choose_cpu(cpumask);
 
                 mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION), 1 << cpuid);
         } else {