kernel/irq/migration.c

   1 #include <linux/irq.h>
   2
   3 #if defined(CONFIG_GENERIC_PENDING_IRQ)
   4
   5 void set_pending_irq(unsigned int irq, cpumask_t mask)
   6 {
   7         irq_desc_t *desc = irq_desc + irq;
   8         unsigned long flags;
   9
  10         spin_lock_irqsave(&desc->lock, flags);
  11         desc->move_irq = 1;
  12         pending_irq_cpumask[irq] = mask;
  13         spin_unlock_irqrestore(&desc->lock, flags);
  14 }
  15
  16 void move_native_irq(int irq)
  17 {
  18         cpumask_t tmp;
  19         irq_desc_t *desc = irq_descp(irq);
  20
  21         if (likely(!desc->move_irq))
  22                 return;
  23
  24         /*
  25          * Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
  26          */
  27         if (CHECK_IRQ_PER_CPU(desc->status)) {
  28                 WARN_ON(1);
  29                 return;
  30         }
  31
  32         desc->move_irq = 0;
  33
  34         if (likely(cpus_empty(pending_irq_cpumask[irq])))
  35                 return;
  36
  37         if (!desc->handler->set_affinity)
  38                 return;
  39
  40         assert_spin_locked(&desc->lock);
  41
  42         cpus_and(tmp, pending_irq_cpumask[irq], cpu_online_map);
  43
  44         /*
  45          * If there was a valid mask to work with, please
  46          * do the disable, re-program, enable sequence.
  47          * This is *not* particularly important for level triggered
  48          * but in a edge trigger case, we might be setting rte
  49          * when an active trigger is comming in. This could
  50          * cause some ioapics to mal-function.
  51          * Being paranoid i guess!
  52          */
  53         if (unlikely(!cpus_empty(tmp))) {
  54                 if (likely(!(desc->status & IRQ_DISABLED)))
  55                         desc->handler->disable(irq);
  56
  57                 desc->handler->set_affinity(irq,tmp);
  58
  59                 if (likely(!(desc->status & IRQ_DISABLED)))
  60                         desc->handler->enable(irq);
  61         }
  62         cpus_clear(pending_irq_cpumask[irq]);
  63 }
  64
  65 #endif