     (  do_IRQ () , -
   ).  do_IRQ ()    
    ,     
ret_from_intr().

 ret_from_intr (),      ,    -
.   ,       -
  (   4, "  -
",   need_resched).        
     (..   -
  ),    schedule ().  
    (..     ), 
 schedule () ,     preempt_count
  (       ).
    schedule ()      ,
       -
  ,    .

  86, ,    , 
  arch/i386/kernel/entry.S,      ї 
 arch/i386/kernel/irq. .     -
   .

 /proc/interrupts

  procfs    ,  
         /.   
    procfs     , 
     .      //
interrupts,   ,     .
         
.

CPUO

0: 3602371 XT-PIC    timer

1: 3048     XT-PIC    i8042

2:         XT-PIC    cascade

4: 2689466 XT-PIC    uhci-hcd, ethO

5:         XT-PIC    EMU10K1

12: 85077   XT-PIC    uhci-hcd

15: 24571   XT-PIC    aic7xxx
NMI: 0

LOC: 3602236
ERR: 0

     .   
     0-2, 4, 5, 12  15. ,  
  ,  .     
     .     -
    ,       -
.

                                                123