Kernel code interrupted by Timer

[anish kumar]

On Sat, 2013-02-09 at 14:57 +0800, Peter Teoh wrote:
> 
> 
> On Sat, Feb 9, 2013 at 1:47 PM, anish kumar 
> .
>         Timer interrupts is supposed to cause scheduling and scheduler
>         may or
>         may not pick up your last process(we always use the term
>         "task" in
>         kernel space) after handling timer interrupt.
>         >
>         
> 
> 
> Sorry if I may disagree, correct me if wrong.   Timer interrupt and
> scheduler is two different thing.   I just counted in the "drivers"
> subdirectory, there are at least more than 200 places where
> "setup_timer()" is called, and these have nothing to do with
> scheduling.   For eg, heartbeat operation etc.  Not sure I
> misunderstood something?
Have a look at kernel/timer.c and kernel/hrtimer.c.
There are many sched() calls in these files.This will invoke scheduler.
> 
> 
> -- 
> Regards,
> Peter Teoh