[question] I doublt on timer interrput.

[liyu]

Hi, all:

   I have one question about timer interrupt (i386 architecture).

   As we known, the timer emit HZ times interrputs per second,
and in i386. The interrupt handler will call scheduler_tick()
each time (on i386 at least, both enable or disable APIC).

   On my Celeron machine(IOW, only one CPU, not SMP/SMT), I defined
a global int variable 'tick_count' in kernel/sched.c, and add one line
of code like follow in scheduler_tick():

   ++tick_count;

   but I found it is not same with content of the /proc/interrupts,
and the differennt between them is not little.
  
   I can not understand why that is.
  
   Any useful idea.



-liyu / NOW~




  

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/