kernel/irq/migration.c

   1
   2 #include <linux/irq.h>
   3 #include <linux/interrupt.h>
   4
   5 #include "internals.h"
   6
   7 void move_masked_irq(int irq)
   8 {
   9         struct irq_desc *desc = irq_to_desc(irq);
  10
  11         if (likely(!(desc->status & IRQ_MOVE_PENDING)))
  12                 return;
  13
  14         /*
  15          * Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
  16          */
  17         if (CHECK_IRQ_PER_CPU(desc->status)) {
  18                 WARN_ON(1);
  19                 return;
  20         }
  21
  22         desc->status &= ~IRQ_MOVE_PENDING;
  23
  24         if (unlikely(cpumask_empty(desc->pending_mask)))
  25                 return;
  26
  27         if (!desc->chip->set_affinity)
  28                 return;
  29
  30         assert_raw_spin_locked(&desc->lock);
  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(cpumask_any_and(desc->pending_mask, cpu_online_mask)
  45                    < nr_cpu_ids))
  46                 if (!desc->chip->set_affinity(irq, desc->pending_mask)) {
  47                         cpumask_copy(desc->affinity, desc->pending_mask);
  48                         irq_set_thread_affinity(desc);
  49                 }
  50
  51         cpumask_clear(desc->pending_mask);
  52 }
  53
  54 void move_native_irq(int irq)
  55 {
  56         struct irq_desc *desc = irq_to_desc(irq);
  57
  58         if (likely(!(desc->status & IRQ_MOVE_PENDING)))
  59                 return;
  60
  61         if (unlikely(desc->status & IRQ_DISABLED))
  62                 return;
  63
  64         desc->chip->mask(irq);
  65         move_masked_irq(irq);
  66         desc->chip->unmask(irq);
  67 }
  68