Re: Bottom halves.

B. James Phillippe (bryan@terran.org)
Fri, 1 Oct 1999 07:52:29 -0700 (PDT)


On Fri, 1 Oct 1999, Rogier Wolff wrote:

> While investigating I found that do_bottom_halves is one of the places
> where interrupts have to wait a long time.
>
> The comment at the top states:
>
> * do_bottom_half() runs at normal kernel priority: all interrupts
> * enabled. do_bottom_half() is atomic with respect to itself: a
> * bottom_half handler need not be re-entrant.
>
> But then the code does:
>
> __sti();
> run_bottom_halves();
> __cli();
>
> Have the comments grown outdated with respect to the actual code?

__sti() enables interrupts on the processor that it was executed on.
__cli() disables them. You snipped the code that shows the reentrancy
locking. I don't see the problem.

-bp

--
# bryan at terran dot org
# http://www.terran.org/~bryan

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