kernel/irq/migration.c

   1
   2 #include <linux/irq.h>
   3
   4 void move_masked_irq(int irq)
   5 {
   6         struct irq_desc *desc = irq_to_desc(irq);
   7         cpumask_t tmp;
   8
   9         if (likely(!(desc->status & IRQ_MOVE_PENDING)))
  10                 return;
  11
  12         /*
  13          * Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
  14          */
  15         if (CHECK_IRQ_PER_CPU(desc->status)) {
  16                 WARN_ON(1);
  17                 return;
  18         }
  19
  20         desc->status &= ~IRQ_MOVE_PENDING;
  21
  22         if (unlikely(cpus_empty(desc->pending_mask)))
  23                 return;
  24
  25         if (!desc->chip->set_affinity)
  26                 return;
  27
  28         assert_spin_locked(&desc->lock);
  29
  30         cpus_and(tmp, desc->pending_mask, cpu_online_map);
  31
  32         /*
  33          * If there was a valid mask to work with, please
  34          * do the disable, re-program, enable sequence.
  35          * This is *not* particularly important for level triggered
  36          * but in a edge trigger case, we might be setting rte
  37          * when an active trigger is comming in. This could
  38          * cause some ioapics to mal-function.
  39          * Being paranoid i guess!
  40          *
  41          * For correct operation this depends on the caller
  42          * masking the irqs.
  43          */
  44         if (likely(!cpus_empty(tmp))) {
  45                 desc->chip->set_affinity(irq,tmp);
  46         }
  47         cpus_clear(desc->pending_mask);
  48 }
  49
  50 void move_native_irq(int irq)
  51 {
  52         struct irq_desc *desc = irq_to_desc(irq);
  53
  54         if (likely(!(desc->status & IRQ_MOVE_PENDING)))
  55                 return;
  56
  57         if (unlikely(desc->status & IRQ_DISABLED))
  58                 return;
  59
  60         desc->chip->mask(irq);
  61         move_masked_irq(irq);
  62         desc->chip->unmask(irq);
  63 }
  64