__restore_flags shows in kernel profile

[Joakim Tjernlund]

> On Thu, 2003-10-23 at 01:55, Joakim Tjernlund wrote:
> > I did a kernel profile(included below) of the bootup of my custom MPC862 board and I
> > noticed that __restore_flags gets a very high count. I am suprised that such a small
> > assembler routine gets such a high count. __cli, _save_flags_ptr and __sti are much lower.
> > A small test program with a tight select loop on fds 0,1 or 2 also makes __restore_flags
> > go wild.
> > Anyone know why?
> >
>
> Simple: when interrupts are off (typically after a __save_flags),
> there can't be any profiling interrupts.  As soon as you restore
> the interrupts (_restore_flags), the interrupt used for profiling
> will fire.

I see, thanks.
Now I wonder what keeps interrupts off for so long and what those nops are doing
in __restore_flags.

   Jocke

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